@font-face { font-family: "DM Sans"; src: url("../assets/dm-sans-variable.ttf") format("truetype"); font-style: normal; font-weight: 400 900; font-display: swap; }
@font-face { font-family: "Space Grotesk"; src: url("../assets/fonts/space-grotesk.woff2") format("woff2"); font-style: normal; font-weight: 300 700; font-display: swap; }
@font-face { font-family: "Noto Serif SC"; src: url("../assets/fonts/noto-serif-sc.woff2") format("woff2"); font-style: normal; font-weight: 200 900; font-display: swap; }
/* WORDTRIS — a typographic playground. One token system for every surface. */
:root {
    color-scheme: dark;
    --bg: #1b2420; --surface: #232e28; --raised: #2c3830;
    --text-main: #f0f0e5; --text-muted: #a6b0a4;
    --line: #455047; --line-soft: #344037; --grid-line: #344138;
    --primary: #d5ed87; --primary-ink: #1c2c20; --accent: #dda48b;
    --success: var(--primary); --danger: #eaa393; --overlay: #09100ca8;
    --tile-font: 'Space Grotesk', 'Noto Serif SC', 'Songti SC', SimSun, serif;
    --display-font: 'Space Grotesk', 'Noto Serif SC', sans-serif;
    --mono-font: Consolas, 'SFMono-Regular', monospace;
    --bg-dark: var(--bg); --panel-bg: var(--surface); --panel-border: var(--line);
    --primary-glow: transparent; --accent-glow: transparent;
    --radius-lg: 14px; --radius-md: 7px; --radius-sm: 5px;
    --shadow-panel: 0 24px 90px #0003; --ease: cubic-bezier(.22, 1, .36, 1);
}
[data-theme="light"] {
    color-scheme: light;
    --bg: #f2f1e9; --surface: #faf9f2; --raised: #e8e9df;
    --text-main: #223128; --text-muted: #627062;
    --line: #c6ccbf; --line-soft: #dfe2d6; --grid-line: #dce1d4;
    --primary: #49632f; --primary-ink: #f4f5e9; --danger: #a64131;
    --overlay: #2c342a40; --shadow-panel: 0 24px 90px #2631211a;
}
* { box-sizing: border-box; margin: 0; padding: 0; -webkit-tap-highlight-color: transparent; }
html { background: var(--bg); }
body { min-height: 100vh; min-height: 100dvh; background: var(--bg); color: var(--text-main); font: 14px/1.6 var(--tile-font); overflow-x: hidden; transition: color .4s, background-color .4s; }
button, input, select { font: inherit; }
button { color: inherit; cursor: pointer; border: 0; background: none; transition: background-color .2s, color .2s, border-color .2s, transform .3s var(--ease); }
button, a { touch-action: manipulation; }
button:active { transform: translateY(2px); }
a { color: inherit; text-underline-offset: 5px; }
button:focus-visible, a:focus-visible, input:focus-visible, select:focus-visible, [tabindex]:focus-visible { outline: 2px solid var(--primary); outline-offset: 4px; }
button:disabled { opacity: .4; cursor: default; }
input, select { color: var(--text-main); accent-color: var(--primary); }
input[type="text"], select { background: var(--surface); border: 1px solid var(--line); border-radius: 6px; padding: 10px 12px; min-width: 0; }
select { max-width: 100%; }
svg.icon { width: 21px; height: 21px; flex: 0 0 auto; fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; }
.svg-library { position: absolute; width: 0; height: 0; overflow: hidden; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
.mono-font, .key-badge { font-family: var(--mono-font); }
::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-thumb { background: var(--line); border-radius: 8px; }

/* Shared controls */
.icon-btn, .round-btn { display: inline-flex; align-items: center; justify-content: center; gap: 7px; height: 42px; min-width: 42px; padding: 8px; border-radius: 50%; color: var(--text-muted); }
.icon-btn:hover, .round-btn:hover { background: var(--raised); color: var(--text-main); }
.round-btn { border: 1px solid var(--line); }
.round-btn:hover { border-color: var(--text-muted); transform: translateY(-2px); }
.round-btn svg { width: 18px; height: 18px; }
.lang-btn, #startLangBtn { font: 12px var(--mono-font); letter-spacing: -.5px; }
.theme-toggle .moon-icon, [data-theme="light"] .theme-toggle .sun-icon { display: none; }
[data-theme="light"] .theme-toggle .moon-icon { display: block; }
.muted { opacity: .55; }
.primary-btn, .hero-start-btn { display: inline-flex; align-items: center; justify-content: center; gap: 20px; background: var(--primary); color: var(--primary-ink); border-radius: 7px; min-height: 48px; padding: 12px 24px; font-weight: 650; }
.primary-btn:hover, .hero-start-btn:hover { filter: brightness(1.07); transform: translateY(-2px); }
.secondary-btn { min-height: 44px; padding: 9px 16px; border-radius: 6px; color: var(--text-muted); border: 1px solid var(--line-soft); }
.secondary-btn:hover { color: var(--text-main); background: var(--raised); }
.text-link { color: var(--text-muted); border-bottom: 1px solid var(--line); padding: 4px 0; display: inline-flex; align-items: center; gap: 10px; font-size: 13px; }
.text-link:hover { color: var(--text-main); border-color: var(--text-main); }

/* Opening: actual letter tiles, no simulated loading percentage. */
.intro-splash { display: none; }
.is-loading .intro-splash { position: fixed; inset: 0; z-index: 200; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 42px; background: var(--bg); }
.intro-splash.is-exiting { opacity: 0; transform: translateY(-18px); transition: opacity .45s, transform .6s var(--ease); pointer-events: none; }
.splash-letters { display: flex; gap: 5px; }
.splash-letters span { width: 42px; height: 48px; display: grid; place-items: center; border-radius: 5px; background: #d5ed87; color: #223128; font: 700 25px/1 var(--tile-font); box-shadow: 0 4px 0 #748346; animation: letter-land .7s var(--ease) both; animation-delay: calc(var(--i) * .065s); }
.splash-letters span:nth-child(n+5) { background: #a9bb9d; box-shadow: 0 4px 0 #687b60; }
.skip-intro { color: var(--text-muted); font-size: 11px; letter-spacing: .1em; }

/* Home — an open typographic composition. */
.start-screen-overlay { position: fixed; inset: 0; z-index: 50; overflow: auto; background: var(--bg); opacity: 0; visibility: hidden; transform: translateY(-16px); transition: opacity .5s, transform .6s var(--ease), visibility 0s .6s, background-color .4s; }
.start-screen-overlay.active { opacity: 1; visibility: visible; transform: none; transition-delay: 0s; }
.home-shell { min-height: 100%; width: min(1480px, 100%); margin: 0 auto; padding: 28px 4.2vw 20px; display: flex; flex-direction: column; }
.home-topbar { display: flex; justify-content: space-between; align-items: center; min-height: 46px; }
.brand-small { font-size: 17px; letter-spacing: .32em; font-weight: 500; }
.home-utilities { display: flex; gap: 12px; }
.home-body { flex: 1; display: grid; grid-template-columns: 46% 54%; align-items: center; padding: 24px 0 36px; min-height: 570px; }
.home-copy { position: relative; z-index: 2; padding: 24px 0; }
.hero-wordmark { font: 700 clamp(98px, 13.8vw, 210px)/.79 var(--display-font); letter-spacing: -.065em; padding-bottom: 14px; margin-left: -.055em; }
.hero-wordmark > span { display: block; }
.hero-wordmark .wordmark-dot { color: #d5ed87; letter-spacing: -.1em; }
[data-theme="light"] .hero-wordmark .wordmark-dot { color: #6e8b42; }
.home-tagline { font-size: clamp(15px, 1.6vw, 23px); letter-spacing: .17em; margin: 26px 0 40px; }
.mode-selector { display: flex; width: min(350px, 90%); border-bottom: 1px solid var(--line); position: relative; }
.mode-card { flex: 1; position: relative; padding: 10px 0 12px; color: var(--text-muted); font-size: 15px; letter-spacing: .14em; text-align: left; }
.mode-card::after { content: ''; position: absolute; bottom: -1px; left: 0; width: 46px; height: 2px; background: var(--primary); transform: scaleX(0); transform-origin: left; transition: transform .35s var(--ease); }
.mode-card.active { color: var(--primary); }
.mode-card.active::after { transform: scaleX(1); }
.mode-card:hover { color: var(--text-main); }
.mode-caption { min-height: 24px; font-size: 13px; color: var(--text-muted); letter-spacing: .12em; margin: 15px 0 24px; }
.mode-caption.changing { animation: caption-enter .35s var(--ease); }
.start-cta-row { display: flex; gap: 24px; align-items: center; }
.hero-start-btn { width: 260px; min-height: 60px; justify-content: space-between; padding: 12px 25px; font-size: 19px; }
.hero-start-btn svg { width: 26px; height: 26px; transition: transform .3s var(--ease); }
.hero-start-btn svg, .hero-start-btn use { color: var(--primary-ink); stroke: var(--primary-ink); }
.hero-start-btn:hover svg { transform: translate(3px, -3px); }
.home-footer { display: flex; align-items: center; justify-content: space-between; gap: 20px; border-top: 1px solid var(--line); padding-top: 19px; font-size: 11px; letter-spacing: .12em; color: var(--text-muted); }
.home-footer-links { display: flex; align-items: center; }
.home-footer-links > * { padding: 0 22px; border-left: 1px solid var(--line); white-space: nowrap; }
.home-footer-links > :last-child { padding-right: 0; }
.home-footer button:hover { color: var(--primary); }
.home-record { font-family: var(--mono-font); }
.home-record strong { color: var(--primary); font-weight: 400; font-size: 14px; margin-left: 9px; }
.is-loading:not(.is-ready) .home-body, .is-loading:not(.is-ready) .home-topbar, .is-loading:not(.is-ready) .home-footer { opacity: 0; }
.is-ready .start-screen-overlay.active .home-copy { animation: surface-enter .9s var(--ease) both; }
.is-ready .start-screen-overlay.active .home-topbar { animation: surface-enter .8s var(--ease) both; }
.is-ready .start-screen-overlay.active .home-footer { animation: surface-enter .8s .2s var(--ease) both; }

/* The sculpture stays live HTML, so letters react to the pointer. */
.letter-sculpture { width: 100%; height: min(600px, 49vw); position: relative; contain: layout; --art-scale: 1; }
.tile-canvas { width: 580px; height: 600px; position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%) scale(var(--art-scale)); transform-origin: center; }
.sculpture-parallax { position: absolute; inset: 0; transform: translate(var(--pointer-x, 0px), var(--pointer-y, 0px)); transition: transform .8s var(--ease); }
.art-grid { position: absolute; left: 65px; top: 40px; width: 470px; height: 510px; opacity: .55; background-image: linear-gradient(var(--line) 1px, transparent 1px), linear-gradient(90deg, var(--line) 1px, transparent 1px); background-size: 94px 94px; transform: rotate(3deg); mask-image: radial-gradient(ellipse, #000 15%, transparent 72%); }
.art-orbit { position: absolute; inset: 0; width: 580px; height: 600px; stroke: var(--text-muted); fill: none; stroke-width: 1; opacity: .8; }
.art-orbit .orbit-dashed { stroke-dasharray: 4 5; }
.art-orbit circle { fill: var(--bg); }
.art-cluster { display: grid; position: absolute; gap: 4px; animation: cluster-float 7s ease-in-out infinite; }
.word-cluster { grid-template-columns: repeat(4, 88px); left: 2px; top: 157px; --rotation: 9deg; transform: rotate(9deg); }
.tris-cluster { grid-template-columns: 88px; left: 406px; top: 91px; --rotation: -7deg; animation-delay: -2.3s; transform: rotate(-7deg); }
.play-cluster { grid-template-columns: repeat(2, 88px); left: 133px; top: 345px; --rotation: -10deg; animation-delay: -4.5s; transform: rotate(-10deg); }
.play-cluster .art-tile:nth-child(3), .play-cluster .art-tile:nth-child(4) { grid-column: 2; }
.art-tile { width: 88px; height: 88px; position: relative; border-radius: 8px; display: grid; place-items: center; font: 750 48px/1 var(--tile-font); color: #233025; background: #d5ed87; box-shadow: 0 7px 0 #788a45, 0 12px 22px #0002, inset 0 1px 2px #fff7; transition: transform .45s var(--ease); user-select: none; }
.art-tile::after { content: ''; position: absolute; inset: 0; border-radius: inherit; background: url('../assets/tile-lime.png') center/110% 110%; mix-blend-mode: luminosity; opacity: .16; pointer-events: none; }
.art-tile::before { content: ''; width: 5px; height: 5px; background: #233025; border-radius: 50%; position: absolute; top: 10px; left: 10px; }
.sage .art-tile { background: #a9bb9d; box-shadow: 0 7px 0 #5e7057, 0 12px 22px #0002, inset 0 1px 2px #fff7; }
.coral .art-tile { background: #dda48b; box-shadow: 0 7px 0 #92644f, 0 12px 22px #0002, inset 0 1px 2px #fff7; }
.art-tile:hover { transform: translateY(-10px) rotate(-5deg); }
.outline-tile { position: absolute; left: 505px; top: 449px; width: 70px; height: 70px; border: 1px solid var(--text-muted); border-radius: 6px; transform: rotate(6deg); }
.outline-tile::after { content: ''; position: absolute; width: 4px; height: 4px; top: 8px; right: 8px; background: var(--text-main); border-radius: 50%; }
.is-ready .start-screen-overlay.active .art-tile:not(.arrived) { animation: tile-arrive .85s var(--ease) both; animation-delay: calc(.08s * var(--i)); }
.start-screen-overlay:not(.active) .art-cluster, .start-screen-overlay[inert] .art-cluster { animation-play-state: paused; }

/* Gameplay */
.app-header { width: min(1360px, 100%); margin: 0 auto; min-height: 88px; padding: 18px 4.2vw; display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.logo-group { display: flex; align-items: center; gap: 15px; }
.logo-title { font: 700 29px/1 var(--display-font); letter-spacing: -.065em; }
.logo-title::after { content: '.'; color: var(--primary); }
.logo-subtitle { display: none; }
.header-actions { display: flex; gap: 7px; align-items: center; }
.mode-badge-pill { font-size: 12px; color: var(--text-muted); letter-spacing: .15em; }
.mode-btn { border-radius: 0; padding: 8px 16px; margin-right: 12px; border-right: 1px solid var(--line); }
.game-container { display: grid; grid-template-columns: 172px minmax(0, auto) 300px; gap: 56px; align-items: start; justify-content: center; width: min(1120px, calc(100% - 80px)); margin: 18px auto 25px; }
.left-sidebar { padding-top: 15px; display: flex; flex-direction: column; gap: 28px; }
.stat-group { display: flex; flex-direction: column; gap: 20px; }
.stat-label { color: var(--text-muted); font-size: 11px; letter-spacing: .12em; }
.stat-value { font-size: 26px; line-height: 1.4; font-weight: 500; font-variant-numeric: tabular-nums; }
.score-group .stat-card:first-child .stat-value { font-size: 70px; font-weight: 650; line-height: 1.2; letter-spacing: -.06em; }
.score-group .sub-card { padding-top: 16px; border-top: 1px solid var(--line); }
.next-preview-card { padding: 20px 0; border-block: 1px solid var(--line); }
.next-canvas-wrapper { display: flex; padding: 10px 0 0; }
.level-group { flex-direction: row; justify-content: space-between; }
.controls-guide-card { display: none; }
.sidebar-help { color: var(--text-muted); display: flex; gap: 8px; align-items: center; font-size: 11px; }
.center-stage { display: flex; flex-direction: column; align-items: center; min-width: 0; }
.board-frame { border: 1px solid var(--line); background: var(--bg); border-radius: 3px; overflow: hidden; }
.board-canvas-wrapper { position: relative; width: fit-content; line-height: 0; touch-action: none; }
#boardCanvas { display: block; }
.mode-hint-bar { order: 2; width: 100%; padding: 12px 0 4px; color: var(--text-muted); text-align: center; font-size: 10px; letter-spacing: .06em; }
.mode-hint-icon { display: none; }
.mode-hint-text strong { font-weight: 400; }
.board-keycaps { display: flex; gap: 7px; margin-top: 10px; order: 3; }
.board-keycaps button { min-width: 34px; height: 30px; border: 1px solid var(--line); border-radius: 5px; font: 11px var(--mono-font); color: var(--text-muted); padding: 0 9px; }
.board-keycaps button:hover { background: var(--raised); color: var(--text-main); }
.right-panel { padding-top: 13px; display: flex; flex-direction: column; min-width: 0; }
.panel-title-row, .panel-title { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.panel-title { font-size: 17px; font-weight: 550; flex: 1; letter-spacing: .07em; }
.badge-count { color: var(--text-muted); font: 14px var(--mono-font); }
.quick-settings-btn { font-size: 0; width: 28px; height: 28px; color: var(--text-muted); }
.quick-settings-btn::after { content: '↗'; font-size: 20px; }
.panel-hint { color: var(--text-muted); font-size: 11px; margin: 8px 0 22px; }
.word-list-container { max-height: min(580px, calc(100dvh - 240px)); overflow: auto; padding-right: 4px; }
.word-card { cursor: pointer; padding: 18px 12px; border-top: 1px solid var(--line); transition: background-color .3s; }
.word-card-entering { animation: caption-enter .24s var(--ease) both; }
.word-card:hover, .word-card.hovered { background: var(--surface); }
.word-card:focus-visible { outline-offset: -2px; }
.word-card-top, .word-spelling-wrap { display: flex; align-items: center; gap: 8px; }
.word-card-top { justify-content: space-between; }
.word-spelling { font-size: 27px; font-weight: 650; letter-spacing: .13em; }
.word-color-dot { display: none; }
.word-points-badge { color: var(--primary); font: 20px var(--mono-font); }
.word-speak-btn, .lex-speak-btn { font-size: 0; width: 30px; height: 30px; border-radius: 50%; color: var(--text-muted); flex-shrink: 0; }
.word-speak-btn::after, .lex-speak-btn::after { content: '♪'; font-size: 19px; }
.word-speak-btn:hover, .lex-speak-btn:hover { background: var(--raised); color: var(--primary); }
.word-meta-row { display: flex; flex-wrap: wrap; align-items: center; gap: 5px; margin-top: 3px; }
.word-phonetic { font-size: 13px; color: var(--text-muted); }
.word-dir-tag, .word-meta-row .word-formula, .syllabus-badge, .word-card-footer { display: none; }
.shortcut-badge { margin-left: auto; font: 10px var(--mono-font); border: 1px solid var(--line); border-radius: 3px; padding: 0 4px; color: var(--text-muted); }
.word-meaning { font-size: 13px; line-height: 1.7; margin-top: 8px; color: var(--text-muted); overflow: hidden; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; }
.word-preview { position: fixed; z-index: 40; width: 360px; max-width: calc(100vw - 32px); max-height: calc(100dvh - 32px); overflow: auto; overscroll-behavior: contain; border: 1px solid var(--line); border-radius: 12px; background: var(--surface); box-shadow: var(--shadow-panel); opacity: 0; transform: translateY(6px); pointer-events: none; transition: opacity .18s ease, transform .24s var(--ease); }
.word-preview.is-visible { opacity: 1; transform: translateY(0); pointer-events: auto; transition: opacity .18s ease, transform .24s var(--ease), top .2s var(--ease), left .2s var(--ease); }
.word-preview[hidden] { display: none; }
.word-preview-header { position: sticky; top: 0; z-index: 1; display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 12px 18px; border-bottom: 1px solid var(--line-soft); background: var(--surface); color: var(--text-muted); font-size: 13px; }
.word-preview-content { padding: 20px; }
.word-preview .detail-letters-row { margin-bottom: 18px; }
.word-preview .tetris-tile-preview { width: 32px; height: 36px; font-size: 20px; }
.word-preview h2 { font-size: 32px; font-weight: 550; line-height: 1.2; letter-spacing: -.035em; overflow-wrap: anywhere; }
.word-preview-meaning { margin: 20px 0; font-size: 16px; line-height: 1.85; overflow-wrap: anywhere; }
.word-preview .dict-main-btn { font-size: 14px; }
.category-badge { font-size: 10px; padding-right: 6px; color: var(--text-muted); }
.empty-words-placeholder { border-top: 1px solid var(--line); padding: 55px 0 35px; text-align: center; color: var(--text-muted); }
.placeholder-icon { font-size: 0; margin-bottom: 15px; }
.placeholder-icon::after { content: 'a b c'; font: 500 42px/1 var(--tile-font); letter-spacing: .05em; color: var(--line); }
.placeholder-text { font-size: 13px; }
.placeholder-hint { font-size: 11px; margin-top: 8px; line-height: 1.9; }
.panel-lexicon-link { align-self: flex-end; margin-top: 24px; font-size: 11px; color: var(--text-muted); }
.game-footer { display: flex; align-items: center; gap: 20px; color: var(--text-muted); font-size: 10px; letter-spacing: .08em; width: min(1120px, calc(100% - 80px)); margin: 0 auto 22px; }
.game-footer::after { content: ''; height: 1px; background: var(--line-soft); flex: 1; }
.mobile-controls { display: none; }
.workspace-enter .game-container { animation: surface-enter .7s .15s var(--ease) both; }

/* Dialog transitions also animate out. Inert state is managed in experience.js. */
.modal-overlay, .settings-modal-overlay, .lexicon-modal-overlay, .lexicon-detail-overlay, .help-overlay { visibility: hidden; opacity: 0; pointer-events: none; transition: opacity .25s, visibility 0s .3s; }
.modal-overlay.active, .settings-modal-overlay.active, .lexicon-modal-overlay.active, .lexicon-detail-overlay.active, .help-overlay.active { visibility: visible; opacity: 1; pointer-events: auto; transition-delay: 0s; }
.settings-modal-overlay, .lexicon-modal-overlay, .lexicon-detail-overlay, .help-overlay { position: fixed; inset: 0; display: flex; align-items: center; justify-content: center; padding: 26px; background: var(--overlay); backdrop-filter: blur(10px); }
.settings-modal-overlay { z-index: 100; } .lexicon-modal-overlay { z-index: 110; } .help-overlay { z-index: 120; } .lexicon-detail-overlay { z-index: 130; }
.modal-overlay { position: absolute; inset: 0; z-index: 10; display: flex; align-items: center; justify-content: center; padding: 15px; background: var(--overlay); backdrop-filter: blur(8px); line-height: 1.6; }
.modal-box, .settings-modal-box, .lexicon-window, .lexicon-detail-card, .help-window { border: 1px solid var(--line); border-radius: 14px; background: var(--surface); box-shadow: var(--shadow-panel); transform: translateY(24px) scale(.98); transition: transform .45s var(--ease), background-color .4s, border-color .4s; overflow: hidden; }
.active > .modal-box, .active > .settings-modal-box, .active > .lexicon-window, .active > .lexicon-detail-card, .active > .help-window { transform: none; }
.modal-box { padding: 28px 20px; width: 100%; text-align: center; }
.modal-title { font-size: 28px; font-weight: 550; letter-spacing: -.04em; margin-bottom: 16px; }
.modal-btn-group { display: flex; flex-direction: column; gap: 8px; }
.modal-stats { display: grid; gap: 7px; margin: 0 0 24px; font-size: 12px; color: var(--text-muted); }
.modal-stats strong { color: var(--text-main); font-weight: 500; }
.modal-stats #finalScore { color: var(--primary); font-size: 34px; }
.settings-close-btn, .lexicon-close-icon-btn, .detail-close-btn, .dialog-close { width: 36px; height: 36px; border: 1px solid var(--line); border-radius: 50%; color: var(--text-muted); flex-shrink: 0; }
.settings-close-btn:hover, .lexicon-close-icon-btn:hover, .detail-close-btn:hover, .dialog-close:hover { color: var(--text-main); background: var(--raised); transform: rotate(90deg); }

/* Settings: clear rows rather than nested cards. */
.settings-modal-box { width: min(900px, 100%); height: min(720px, calc(100dvh - 52px)); display: flex; flex-direction: column; }
.settings-modal-header, .lexicon-header { display: flex; justify-content: space-between; align-items: center; padding: 26px 30px; gap: 15px; border-bottom: 1px solid var(--line-soft); }
.settings-modal-title, .lexicon-title { font-size: 26px; font-weight: 500; letter-spacing: -.03em; }
.settings-modal-subtitle { display: none; }
.settings-modal-body { display: grid; grid-template-columns: 176px minmax(0, 1fr); flex: 1; min-height: 0; }
.settings-sidebar-nav { display: flex; flex-direction: column; gap: 8px; padding: 22px 14px; border-right: 1px solid var(--line-soft); }
.settings-nav-btn { display: flex; align-items: center; gap: 10px; padding: 11px 14px; text-align: left; border-radius: 6px; color: var(--text-muted); font-size: 15px; }
.settings-nav-btn:hover { background: var(--raised); color: var(--text-main); }
.settings-nav-btn.active { color: var(--primary); background: var(--raised); }
.nav-icon { display: none; }
.settings-tab-panels { overflow: auto; padding: 26px 28px; }
.settings-tab-pane { display: none; }
.settings-tab-pane.active { display: block; animation: caption-enter .35s var(--ease); }
.syllabus-section-header { margin-bottom: 22px; display: flex; gap: 12px; justify-content: space-between; flex-wrap: wrap; }
.syllabus-header-left { display: flex; flex-direction: column; gap: 7px; }
.setting-badge-tag { color: var(--text-main); font-size: 16px; font-weight: 500; }
.syllabus-header-tip, .lang-setting-desc, .setting-description, .board-slider-tip, .board-notice-hint, .settings-save-tip { color: var(--text-muted); font-size: 14px; line-height: 1.8; }
.lang-setting-card { border-top: 1px solid var(--line-soft); }
.lang-setting-row { display: flex; flex-wrap: wrap; align-items: center; gap: 20px; justify-content: space-between; padding: 23px 0; border-bottom: 1px solid var(--line-soft); }
.lang-setting-title { font-size: 16px; margin-bottom: 5px; }
.lang-setting-meta { flex: 1; min-width: 180px; }
.lang-segmented-control { display: flex; gap: 3px; background: var(--bg); border: 1px solid var(--line); border-radius: 6px; padding: 3px; flex-shrink: 0; }
.lang-pill-btn, .appearance-choice { min-height: 40px; padding: 7px 12px; font-size: 14px; color: var(--text-muted); border-radius: 4px; }
.lang-pill-btn.active, .appearance-choice.active { background: var(--raised); color: var(--text-main); }
.lang-select-wrapper { width: 180px; }
.def-lang-dropdown { width: 100%; min-height: 44px; font-size: 16px; }
.lang-status-note, .def-lang-status-note { color: var(--text-muted); font-size: 13px; padding: 10px 0; }
.appearance-title { color: var(--text-muted); font-size: 14px; margin: 20px 0 10px; }
.appearance-control + .syllabus-section-header { margin-top: 26px; }
.note-icon { display: none; }
.appearance-control { display: flex; gap: 10px; }
.appearance-choice { display: flex; align-items: center; justify-content: center; gap: 9px; flex: 1; min-height: 56px; border: 1px solid var(--line); font-size: 15px; }
.appearance-choice.active { border-color: var(--primary); color: var(--primary); }
.appearance-swatch { width: 18px; height: 18px; border-radius: 50%; border: 1px solid #8b9880; }
.appearance-swatch.dark { background: #1b2420; } .appearance-swatch.light { background: #f2f1e9; }
.settings-modal-footer { flex-shrink: 0; padding: 17px 28px; border-top: 1px solid var(--line-soft); display: flex; align-items: center; justify-content: space-between; gap: 15px; }
.settings-confirm-btn { min-height: 44px; flex-shrink: 0; font-size: 15px; }
.board-desktop-controls { display: flex; flex-direction: column; gap: 22px; }
.board-specs-card { display: flex; align-items: center; justify-content: space-between; background: var(--bg); padding: 16px 22px; border-radius: 8px; }
.board-specs-info { display: grid; gap: 8px; }
.board-spec-row { display: flex; gap: 18px; font-size: 14px; color: var(--text-muted); }
.spec-value-highlight, .spec-value-badge { color: var(--text-main); font-family: var(--mono-font); }
.board-ratio-visual-box { position: relative; border: 1px solid var(--primary); display: grid; place-items: center; }
.visual-grid-overlay { position: absolute; inset: 0; background-image: linear-gradient(var(--line-soft) 1px, transparent 1px), linear-gradient(90deg, var(--line-soft) 1px, transparent 1px); }
.visual-ratio-tag { font: 13px var(--mono-font); z-index: 1; background: var(--bg); color: var(--primary); }
.slider-header-row { display: flex; justify-content: space-between; gap: 15px; align-items: center; }
.slider-label-group { display: grid; gap: 3px; }
.slider-title { font-size: 15px; } .slider-val-bubble { font: 17px var(--mono-font); color: var(--primary); }
.board-range-input { width: 100%; height: 4px; margin: 18px 0 7px; cursor: pointer; }
.board-presets-section { display: grid; gap: 10px; }
.presets-label { color: var(--text-muted); font-size: 13px; }
.board-presets-grid, .presets-btn-group { display: flex; flex-wrap: wrap; gap: 6px; }
.board-preset-chip, .syllabus-preset-btn, .diff-preset-chip { border: 1px solid var(--line); color: var(--text-muted); border-radius: 5px; padding: 6px 9px; font-size: 13px; }
.board-preset-chip:hover, .syllabus-preset-btn:hover, .diff-preset-chip:hover { color: var(--primary); border-color: var(--primary); }
.diff-preset-chip.active { border-color: var(--primary); color: var(--primary); background: var(--raised); }

/* Difficulty & Letter Probability Styles */
.diff-level-card { background: var(--bg); border: 1px solid var(--line-soft); border-radius: 8px; padding: 16px 20px; margin-bottom: 22px; }
.diff-level-header { display: flex; align-items: center; justify-content: space-between; gap: 15px; }
.diff-level-title-group { display: grid; gap: 4px; }
.diff-level-pre { font-size: 13px; color: var(--text-muted); }
.diff-level-badge-wrap { display: flex; align-items: center; gap: 10px; }
.diff-level-badge { font-size: 17px; font-weight: 600; color: var(--primary); font-family: var(--mono-font); }
.diff-level-sub { font-size: 12px; font-family: var(--mono-font); padding: 2px 7px; border-radius: 4px; background: var(--raised); color: var(--text-muted); }
.diff-level-number-bubble { width: 38px; height: 38px; border-radius: 50%; border: 2px solid var(--primary); color: var(--primary); font-size: 18px; font-family: var(--mono-font); font-weight: 700; display: flex; align-items: center; justify-content: center; flex-shrink: 0; background: var(--raised); }
.diff-level-desc { font-size: 14px; color: var(--text-muted); margin-top: 10px; line-height: 1.6; }

.diff-slider-wrap { margin-bottom: 20px; }
.diff-slider-ticks { display: flex; justify-content: space-between; margin-top: 6px; font-size: 12px; color: var(--text-muted); font-family: var(--mono-font); }

.diff-preview-box { background: var(--bg); border: 1px solid var(--line-soft); border-radius: 8px; padding: 18px 20px; margin: 22px 0 16px; }
.diff-preview-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 14px; flex-wrap: wrap; gap: 8px; }
.diff-preview-title { font-size: 15px; font-weight: 500; color: var(--text-main); }
.diff-preview-tag { font-size: 12px; color: var(--text-muted); }
.diff-preview-section-label { font-size: 13px; color: var(--text-muted); margin-bottom: 10px; }
.diff-top-letters-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; }
.diff-letter-item { display: flex; align-items: center; gap: 10px; background: var(--raised); border-radius: 6px; padding: 8px 10px; border: 1px solid var(--line-soft); }
.diff-letter-badge { width: 30px; height: 30px; border-radius: 4px; background: var(--bg); color: var(--primary); font-family: var(--mono-font); font-size: 15px; font-weight: 700; display: flex; align-items: center; justify-content: center; border: 1px solid var(--line); flex-shrink: 0; }
.diff-letter-info { flex: 1; min-width: 0; }
.diff-letter-percent { font-size: 13px; font-family: var(--mono-font); font-weight: 600; color: var(--text-main); }
.diff-letter-bar-bg { height: 4px; background: var(--line); border-radius: 2px; margin-top: 4px; overflow: hidden; }
.diff-letter-bar-fill { height: 100%; background: var(--primary); border-radius: 2px; transition: width 0.3s ease; }
.diff-rare-summary { margin-top: 14px; padding-top: 12px; border-top: 1px dashed var(--line-soft); display: flex; justify-content: space-between; font-size: 13px; color: var(--text-muted); }
.diff-rare-val { font-family: var(--mono-font); color: var(--text-main); }
.diff-notice-hint { margin-top: 10px; }

.board-actions-row { display: grid; gap: 10px; }
.board-reset-btn { font-size: 14px; color: var(--primary); justify-self: start; }
.board-mobile-notice { display: flex; gap: 15px; padding: 20px; background: var(--bg); border-radius: 8px; }
.board-mobile-notice-icon { display: none; }
.board-mobile-notice-title { font-size: 16px; } .board-mobile-notice-desc { font-size: 14px; color: var(--text-muted); margin-top: 8px; }
.setting-row { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 24px 0; border-top: 1px solid var(--line-soft); }
.setting-title-line { display: flex; align-items: center; flex-wrap: wrap; gap: 9px; margin-bottom: 8px; }
.setting-title-line .setting-badge-tag { font-size: 13px; border: 1px solid var(--line); padding: 2px 5px; border-radius: 3px; color: var(--text-muted); }
.setting-name { font-size: 16px; } .setting-count-pill { font: 13px var(--mono-font); color: var(--text-muted); }
.setting-examples { display: none; }
.setting-control { display: flex; align-items: center; flex-direction: column; gap: 5px; flex-shrink: 0; }
.toggle-switch { position: relative; display: block; width: 36px; height: 21px; }
.toggle-switch input { position: absolute; inset: 0; width: 100%; height: 100%; opacity: 0; cursor: pointer; z-index: 1; }
.toggle-slider { position: absolute; inset: 0; border-radius: 30px; background: var(--line); transition: background .25s; }
.toggle-slider::after { content: ''; width: 15px; height: 15px; border-radius: 50%; background: var(--bg); position: absolute; left: 3px; top: 3px; transition: transform .3s var(--ease); }
.toggle-switch input:checked + .toggle-slider { background: var(--primary); }
.toggle-switch input:checked + .toggle-slider::after { transform: translateX(15px); }
.toggle-switch input:focus-visible + .toggle-slider { outline: 2px solid var(--primary); outline-offset: 3px; }
.setting-status-text { font-size: 12px; color: var(--text-muted); } .setting-status-text.active { color: var(--primary); }
.active-syllabus-pill { color: var(--primary); font: 13px var(--mono-font); }
.syllabus-presets-bar { display: grid; gap: 10px; margin-bottom: 20px; }
.syllabus-grid { display: grid; grid-template-columns: 1fr; }
.syllabus-item-card { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 14px 0; border-top: 1px solid var(--line-soft); cursor: pointer; }
.syllabus-card-left { min-width: 0; display: flex; align-items: center; gap: 12px; }
.syllabus-card-tag { font-size: 13px; color: var(--text-muted); width: 45px; }
.syllabus-card-title { display: flex; flex-wrap: wrap; align-items: baseline; gap: 10px; }
.syllabus-name { font-size: 15px; } .syllabus-count { font: 13px var(--mono-font); color: var(--text-muted); }
.syllabus-desc { font-size: 13px; color: var(--text-muted); margin-top: 4px; }
.syllabus-checkbox { width: 20px; height: 20px; flex-shrink: 0; cursor: pointer; }

/* Lexicon — an editorial word index */
.lexicon-window { width: min(1120px, 100%); height: min(850px, calc(100dvh - 52px)); display: flex; flex-direction: column; }
.lexicon-title-group { min-width: 0; width: 300px; }
.lexicon-title-line { display: flex; align-items: center; gap: 12px; }
.lexicon-icon, .lexicon-pill-version { display: none; }
.lexicon-progress-wrap { margin-top: 9px; }
.lexicon-progress-stats { display: flex; justify-content: space-between; color: var(--text-muted); font-size: 13px; }
.lexicon-progress-stats strong { color: var(--text-main); font-weight: 400; }
.lexicon-progress-bar-bg { margin-top: 6px; height: 2px; background: var(--line); }
.lexicon-progress-bar-fill { height: 100%; background: var(--primary); transition: width .5s var(--ease); }
.lexicon-header-actions { display: flex; align-items: center; gap: 10px; }
#lexiconRandomBtn { width: auto; padding: 7px 14px; border: 1px solid var(--line); border-radius: 5px; font-size: 14px; }
.lexicon-toolbar { padding: 20px 30px; border-bottom: 1px solid var(--line-soft); display: grid; gap: 16px; }
.lexicon-search-row { display: flex; gap: 20px; align-items: center; }
.lexicon-search-box { min-width: 0; position: relative; flex: 1; display: flex; align-items: center; }
.search-lens-icon { position: absolute; left: 13px; font-size: 0; color: var(--text-muted); }
.search-lens-icon::after { content: '⌕'; font-size: 25px; }
.lexicon-search-input { min-height: 46px; width: 100%; padding: 11px 40px !important; background: var(--bg) !important; font-size: 15px; }
.search-clear-btn { position: absolute; right: 12px; color: var(--text-muted); }
.lexicon-match-pill { font: 14px var(--mono-font); color: var(--text-muted); white-space: nowrap; }
.lexicon-match-pill strong { color: var(--primary); font-weight: 400; }
.lexicon-filter-group { display: flex; align-items: center; gap: 18px; }
.filter-label { color: var(--text-muted); font-size: 13px; white-space: nowrap; }
.lex-len-pills-container { display: flex; gap: 5px; flex-wrap: wrap; }
.lex-len-btn { padding: 5px 11px; font-size: 14px; border-radius: 4px; color: var(--text-muted); border: 1px solid transparent; }
.lex-len-btn:hover { background: var(--raised); } .lex-len-btn.active { border-color: var(--primary); color: var(--primary); }
.len-count-badge { font-size: 12px; margin-left: 4px; }
.lexicon-secondary-row { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 12px; }
.lex-dropdown-field { display: grid; gap: 5px; } .lex-dropdown-field label { color: var(--text-muted); font-size: 13px; }
.lex-select { width: 100%; min-height: 42px; font-size: 16px; padding: 7px 9px; }
.lexicon-scroll-body { overflow: auto; flex: 1; padding: 5px 30px 20px; min-height: 0; }
.lexicon-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); column-gap: 18px; }
.lexicon-word-card { padding: 12px 10px; border-bottom: 1px solid var(--line); cursor: pointer; min-width: 0; transition: background .25s; animation: caption-enter .4s var(--ease) both; }
.lexicon-word-card:hover { background: var(--raised); }
.lexicon-word-card.unlocked .lex-word-name { color: var(--primary); }
.lex-card-header, .lex-word-title-group { display: flex; align-items: center; gap: 5px; } .lex-card-header { justify-content: space-between; flex-wrap: wrap; gap: 8px 12px; }
.lex-word-name { overflow-wrap: anywhere; font-size: 26px; font-weight: 550; letter-spacing: -.035em; }
.lex-card-dict-link { font-size: 12px; color: var(--text-muted); text-decoration: none; white-space: nowrap; }
.lex-card-tags { display: flex; gap: 5px; align-items: center; flex-wrap: wrap; margin-top: 6px; }
.lex-badge, .lex-syllabus-badge, .detail-syllabus-pill { display: inline-flex; border: 1px solid var(--line); border-radius: 3px; padding: 1px 5px; font-size: 12px; color: var(--text-muted); line-height: 1.6; }
.lex-card-tags .badge-standard, .lex-card-tags .badge-len, .lex-card-tags .lex-syllabus-badge { display: none; }
.lex-phonetic { font-size: 15px; color: var(--text-muted); }
.lex-status-badge { font-size: 12px; color: var(--text-muted); margin-left: auto; } .lex-status-badge.unlocked { color: var(--primary); }
.lex-card-meaning { font-size: 16px; line-height: 1.8; color: var(--text-muted); margin-top: 6px; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; min-height: 0; }
.lex-card-footer { display: flex; align-items: center; justify-content: space-between; font-size: 12px; color: var(--text-muted); margin-top: 8px; }
.lex-detail-link { opacity: 1; transform: none; transition: opacity .2s, transform .2s; color: var(--primary); }
.lexicon-word-card:hover .lex-detail-link, .lexicon-word-card:focus-visible .lex-detail-link { opacity: 1; transform: none; }
.lexicon-load-more { text-align: center; font-size: 13px; color: var(--text-muted); padding: 25px; }
.lexicon-empty-state { text-align: center; padding: 55px 15px; color: var(--text-muted); }
.empty-icon { display: none; } .empty-title { color: var(--text-main); font-size: 20px; }
.empty-sub { font-size: 15px; margin: 10px 0 25px; } .empty-reset-btn { font-size: 15px; min-height: 40px; }
.lexicon-footer { flex-shrink: 0; padding: 16px 30px; border-top: 1px solid var(--line-soft); display: flex; justify-content: space-between; align-items: center; gap: 15px; }
.lex-footer-tip { color: var(--text-muted); font-size: 13px; } .lex-confirm-btn { min-height: 44px; flex-shrink: 0; font-size: 14px; }

/* Word detail */
.lexicon-detail-card { width: min(620px, 100%); max-height: calc(100dvh - 52px); display: flex; flex-direction: column; }
.detail-header { flex-shrink: 0; padding: 18px 24px; border-bottom: 1px solid var(--line-soft); display: flex; align-items: center; justify-content: space-between; }
.detail-pill-tag { color: var(--text-muted); font-size: 13px; letter-spacing: .12em; }
.detail-content { min-height: 0; overflow: auto; padding: 28px; }
.detail-letters-row { display: flex; flex-wrap: wrap; gap: 5px; margin-bottom: 25px; }
.tetris-tile-preview { width: 44px; height: 48px; display: grid; place-items: center; font-weight: 700; font-size: 25px; border-radius: 5px; color: #223128; box-shadow: inset 0 -3px #0002; }
.detail-title-line { display: flex; flex-wrap: wrap; gap: 12px; justify-content: space-between; align-items: center; }
.detail-word-title { font-size: 40px; font-weight: 550; letter-spacing: -.05em; line-height: 1.2; }
.detail-sound-btn { padding: 6px 10px; font-size: 14px; color: var(--primary); }
.detail-meta-row, .detail-tags-row { display: flex; align-items: center; gap: 7px; margin-top: 12px; flex-wrap: wrap; }
.detail-stat-box { margin: 24px 0; border-block: 1px solid var(--line-soft); padding: 13px 0; display: flex; justify-content: space-between; gap: 10px; color: var(--text-muted); font-size: 13px; }
.detail-section { margin-top: 24px; } .detail-section-title { font-size: 14px; color: var(--text-muted); margin-bottom: 10px; }
.detail-section-title-row { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 10px; }
.detail-def-lang-wrapper { display: flex; gap: 6px; align-items: center; } .detail-def-lang-label { display: none; }
.detail-def-lang-select { min-height: 40px; padding: 7px 9px; font-size: 16px; }
.detail-meaning-box { font-size: 17px; line-height: 1.9; white-space: pre-line; user-select: text; }
.detail-dict-actions { display: grid; gap: 16px; }
.dict-main-btn { display: flex; justify-content: space-between; align-items: center; border: 1px solid var(--line); border-radius: 6px; padding: 12px 15px; text-decoration: none; font-size: 15px; }
.dict-btn-inner { display: grid; gap: 3px; } .dict-btn-desc { color: var(--text-muted); font-size: 12px; }
.dict-btn-icon { display: none; }
.detail-sub-dicts { display: flex; gap: 9px; flex-wrap: wrap; font-size: 12px; color: var(--text-muted); } .sub-dict-tag { text-decoration: none; }
.detail-nav-footer { flex-shrink: 0; display: flex; justify-content: space-between; align-items: center; gap: 8px; padding: 12px 20px; border-top: 1px solid var(--line-soft); }
.nav-btn { width: auto; border-radius: 5px; padding: 7px 10px; font-size: 14px; } .nav-key-tip { font-size: 12px; color: var(--text-muted); }
.lexicon-discovery-toast { position: fixed; z-index: 140; left: 50%; bottom: 30px; transform: translate(-50%, 20px); opacity: 0; pointer-events: none; background: var(--raised); color: var(--text-main); padding: 12px 22px; border: 1px solid var(--line); border-radius: 7px; transition: opacity .3s, transform .3s var(--ease); font-size: 12px; }
.lexicon-discovery-toast.show { transform: translate(-50%, 0); opacity: 1; }
.lexicon-discovery-toast { width: min(380px, calc(100% - 32px)); bottom: 22px; }
.toast-icon { display: none; }
.toast-title { font-size: 11px; color: var(--text-muted); }
.toast-title strong { color: var(--primary); font-size: 15px; margin-left: 8px; font-weight: 500; }
.toast-meaning { margin-top: 3px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--text-muted); font-size: 10px; }

/* Instructions only appear when requested. */
.help-window { width: min(940px, 100%); max-height: calc(100dvh - 52px); overflow: auto; padding: 28px; }
.help-header { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 28px; }
.help-title { font-size: 27px; font-weight: 500; }
.help-body { display: grid; grid-template-columns: minmax(0, 1fr) 294px; gap: 32px; align-items: start; }
.help-guide { min-width: 0; }
.help-example { display: flex; gap: 5px; align-items: center; padding: 20px 0 25px; }
.help-example span { width: 50px; height: 53px; display: grid; place-items: center; background: #d5ed87; color: #223128; border-radius: 5px; font-weight: 650; font-size: 27px; box-shadow: 0 3px #748346; }
.help-example strong { margin-left: 12px; color: var(--primary); font: 20px var(--mono-font); }
.help-step { display: grid; grid-template-columns: 28px 1fr; gap: 15px; padding: 17px 0; border-top: 1px solid var(--line-soft); }
.help-step > span { color: var(--text-muted); font: 10px/2.2 var(--mono-font); } .help-step h3 { font-size: 14px; font-weight: 500; }
.help-step p { font-size: 12px; color: var(--text-muted); margin-top: 5px; }
.help-keys { display: flex; flex-wrap: wrap; gap: 14px; margin: 22px 0 28px; color: var(--text-muted); font-size: 10px; }
kbd { border: 1px solid var(--line); padding: 2px 5px; border-radius: 3px; font: 10px var(--mono-font); color: var(--text-main); margin-right: 4px; }
.help-window > .primary-btn { width: 100%; margin-top: 24px; }

/* A self-contained classic-mode lesson; never reads or mutates the live board. */
.help-demo { padding: 18px 20px 16px; background: var(--bg); border: 1px solid var(--line-soft); border-radius: 10px; }
.help-demo-header { display: flex; align-items: center; justify-content: space-between; gap: 8px; }
.help-demo-header h3 { font-size: 11px; font-weight: 400; color: var(--text-muted); letter-spacing: .03em; }
.help-demo-actions { display: flex; gap: 3px; }
.help-demo-control { display: grid; place-items: center; width: 27px; height: 27px; border-radius: 50%; color: var(--text-muted); }
.help-demo-control:hover { background: var(--raised); color: var(--text-main); }
.help-demo-control svg { width: 15px; height: 15px; }
.help-demo-score { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; margin: 14px 0 10px; color: var(--text-muted); font-size: 9px; }
.help-demo-score strong { color: var(--text-main); font: 400 21px/1.2 var(--tile-font); font-variant-numeric: tabular-nums; }
.help-demo-stage { position: relative; }
.help-demo-board { position: relative; width: 100%; aspect-ratio: 10 / 12; border: 1px solid var(--line); border-radius: 3px; overflow: hidden; background-image: linear-gradient(var(--grid-line) 1px, transparent 1px), linear-gradient(90deg, var(--grid-line) 1px, transparent 1px); background-size: 10% calc(100% / 12); }
.help-demo-tile { position: absolute; left: calc(var(--col) * 10% + 1.5px); top: calc(var(--row) * 100% / 12 + 1.5px); width: calc(10% - 3px); height: calc(100% / 12 - 3px); border-radius: 3px; display: grid; place-items: center; background: #bcb0cf; color: #223128; box-shadow: inset 0 -2px #20312726; font-size: 13px; font-weight: 650; line-height: 1; }
.help-demo-seed { background: #dda48b; }
.help-demo-piece, .help-demo-ghost { position: absolute; inset: 0; transform: translate(calc(var(--piece-x, 1) * 10%), calc(var(--piece-y, 0) * 100% / 12)); will-change: transform; }
.help-demo-ghost { --piece-y: 10; opacity: .45; }
.help-demo-ghost .help-demo-tile { background: transparent; border: 1px dashed #bcb0cf; box-shadow: none; }
.help-demo.is-word-ready .help-demo-word-letter { background: #d5ed87; }
.help-demo-key { position: absolute; right: 7px; top: 8px; padding: 2px 6px; border: 1px solid var(--line); border-radius: 4px; font: 9px/1.5 var(--mono-font); color: var(--text-muted); background: var(--bg); }
.help-demo-key:empty { display: none; }
.help-demo-gain { position: absolute; left: 50%; top: 72%; opacity: 0; color: var(--primary); font: 500 24px/1 var(--tile-font); pointer-events: none; }
.help-demo-word { min-height: 52px; position: relative; display: flex; align-items: center; gap: 12px; padding: 10px 13px; margin-top: 12px; border: 1px solid var(--line-soft); border-radius: 5px; transform: scale(calc(1 - var(--demo-press, 0) * .035)); transition: border-color .25s, background-color .25s; }
.help-demo-word-empty { position: absolute; left: 13px; color: var(--text-muted); font-size: 10px; }
.help-demo-word-title { font-size: 21px; letter-spacing: .12em; font-weight: 550; }
.help-demo-word-points { color: var(--primary); font: 12px var(--mono-font); margin-left: auto; }
.help-demo-word-arrow { width: 14px !important; height: 14px !important; color: var(--text-muted); }
.help-demo-word-title, .help-demo-word-points, .help-demo-word-arrow { opacity: 0; }
.help-demo.is-word-ready .help-demo-word { background: var(--surface); border-color: var(--primary); }
.help-demo.is-word-ready .help-demo-word-empty { opacity: 0; }
.help-demo.is-word-ready .help-demo-word-title, .help-demo.is-word-ready .help-demo-word-points, .help-demo.is-word-ready .help-demo-word-arrow { opacity: 1; }
.help-demo-cursor { position: absolute; z-index: 2; width: 23px; height: 27px; opacity: 0; pointer-events: none; fill: var(--text-main); stroke: var(--bg); stroke-width: 1.2; stroke-linejoin: round; filter: drop-shadow(0 2px 2px #0002); }
.help-demo-click-ring { position: absolute; z-index: 1; left: 52%; top: 91%; width: 28px; height: 28px; border: 1px solid var(--primary); border-radius: 50%; opacity: 0; pointer-events: none; }
.help-demo-progress { display: flex; gap: 5px; margin-top: 20px; }
.help-demo-progress span { height: 2px; flex: 1; background: var(--line); transition: background-color .25s; }
.help-demo-progress span.is-current { background: var(--primary); }
.help-demo-caption { margin-top: 9px; min-height: 19px; text-align: center; font-size: 10px; color: var(--text-muted); }
@keyframes surface-enter { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: none; } }
@keyframes caption-enter { from { opacity: 0; transform: translateY(7px); } to { opacity: 1; transform: none; } }
@keyframes letter-land { from { opacity: 0; transform: translateY(-70px) rotate(-12deg); } 65% { opacity: 1; transform: translateY(4px) rotate(2deg); } to { opacity: 1; transform: none; } }
@keyframes tile-arrive { from { opacity: 0; transform: translateY(-75px) rotate(-12deg); } to { opacity: 1; transform: none; } }
@keyframes cluster-float { 0%, 100% { transform: translateY(0) rotate(var(--rotation)); } 50% { transform: translateY(-12px) rotate(calc(var(--rotation) + 2deg)); } }

/* Desktop, tablet and touch layouts */
@media (min-width: 1600px) { .home-shell { padding-top: 35px; padding-bottom: 28px; } .home-body { min-height: 740px; } }
@media (min-width: 901px) and (max-height: 780px) {
    .home-body { min-height: 0; padding: 20px 0 28px; } .hero-wordmark { font-size: clamp(105px, 12.6vw, 174px); }
    .home-tagline { margin: 22px 0 25px; font-size: 17px; } .mode-caption { margin: 10px 0 19px; }
    .hero-start-btn { min-height: 54px; } .letter-sculpture { height: min(520px, 43vw); }
}
@media (max-width: 1150px) and (min-width: 901px) {
    .game-container { grid-template-columns: 136px minmax(0, auto) 255px; gap: 30px; width: calc(100% - 60px); }
    .word-spelling { font-size: 24px; } .hero-start-btn { width: 220px; } .start-cta-row { gap: 18px; }
}
@media (max-width: 900px) and (min-width: 641px) {
    .hero-start-btn { width: 190px; font-size: 16px; }
    .start-cta-row { gap: 16px; }
    .start-cta-row .text-link { font-size: 11px; }
}
@media (max-width: 900px) {
    .help-body { grid-template-columns: minmax(0, 1fr) 250px; gap: 24px; }
    .help-demo { padding: 14px 16px; }
    .app-header { min-height: 66px; padding: 12px 20px; } .logo-title { font-size: 23px; }
    .header-actions { gap: 2px; } .header-actions .icon-btn { min-width: 33px; width: 33px; height: 36px; padding: 6px; }
    .header-actions svg { width: 18px; height: 18px; }
    .header-actions #langSwitchBtn, .header-actions #lexiconBtn, .header-actions #restartBtn, .header-actions #gameHomeBtn { display: none; }
    .header-actions .mode-btn { width: auto; margin-right: 2px; padding-right: 9px; } .mode-badge-pill { font-size: 10px; }
    .game-container { grid-template-columns: 88px minmax(0, 1fr); gap: 0 12px; width: min(520px, calc(100% - 32px)); margin: 10px auto 18px; }
    .left-sidebar { gap: 22px; padding-top: 7px; } .stat-label { font-size: 8px; letter-spacing: .04em; } .stat-value { font-size: 21px; }
    .score-group .stat-card:first-child .stat-value { font-size: 36px; } .score-group { gap: 15px; } .score-group .sub-card { padding-top: 12px; }
    .next-preview-card { padding: 15px 0; } .next-canvas-wrapper { padding: 8px 0 0; } .level-group { flex-direction: column; gap: 12px; }
    .sidebar-help { font-size: 9px; gap: 4px; } .sidebar-help svg { width: 13px; height: 13px; }
    .mode-hint-bar { font-size: 8px; padding: 8px 0 0; } .board-keycaps { display: none; }
    .mobile-controls { display: block; grid-column: 1 / -1; margin-top: 16px; }
    .touch-row { display: grid; grid-template-columns: repeat(5, 1fr); gap: 7px; }
    .touch-btn { min-height: 43px; border: 1px solid var(--line); border-radius: 6px; color: var(--text-main); display: grid; place-items: center; font-size: 19px; touch-action: none; }
    .touch-btn.primary { background: var(--raised); } .touch-btn.accent { color: var(--primary-ink); background: var(--primary); border-color: var(--primary); }
    .touch-btn:active { background: var(--raised); }
    .right-panel { grid-column: 1 / -1; padding-top: 20px; } .panel-title { font-size: 13px; } .panel-hint { margin: 4px 0 13px; font-size: 10px; }
    .word-list-container { max-height: 230px; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 20px; }
    .word-card { padding: 12px; } .word-spelling { font-size: 21px; } .word-points-badge { font-size: 15px; }
    .word-card { -webkit-touch-callout: none; user-select: none; }
    .word-meaning, .word-phonetic { font-size: 10px; } .word-speak-btn { width: 22px; height: 24px; } .shortcut-badge { display: none; }
    .empty-words-placeholder { grid-column: 1 / -1; padding: 22px 0; } .placeholder-icon { display: none; }
    .placeholder-text { font-size: 12px; } .placeholder-hint { font-size: 10px; margin-top: 4px; }
    .panel-lexicon-link { margin-top: 12px; font-size: 10px; } .game-footer { width: calc(100% - 32px); font-size: 8px; margin-bottom: 18px; }
    .modal-box { padding: 23px 15px; } .modal-title { font-size: 24px; } .modal-btn-group { gap: 6px; }
    .modal-btn-group .primary-btn, .modal-btn-group .secondary-btn { min-height: 36px; font-size: 11px; padding: 7px 10px; }
    .modal-box > p { font-size: 10px !important; margin-bottom: 15px !important; }
    .lexicon-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 20px; } .lexicon-secondary-row { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
    .home-shell { padding: 20px 24px 22px; } .home-topbar { min-height: 38px; } .brand-small { font-size: 12px; letter-spacing: .24em; }
    .home-utilities { gap: 7px; } .round-btn { min-width: 34px; height: 34px; padding: 7px; } .round-btn svg { width: 16px; height: 16px; }
    .home-body { display: flex; flex-direction: column; align-items: stretch; padding: 28px 0; min-height: 0; position: relative; }
    .home-copy { display: contents; } .home-title-block { order: 0; }
    .hero-wordmark { font-size: clamp(100px, 30vw, 155px); line-height: .8; letter-spacing: -.09em; width: max-content; }
    .home-tagline { font-size: 12px; letter-spacing: .12em; margin: 18px 0 0; }
    .letter-sculpture { height: 245px; width: 100%; margin: 10px 0 22px; order: 1; } .home-mode-controls { order: 2; }
    .mode-selector { width: 100%; } .mode-card { font-size: 13px; padding: 10px 0; text-align: center; }
    .mode-card::after { width: 36px; left: calc(50% - 18px); }
    .mode-caption { margin: 12px 0 18px; font-size: 11px; text-align: center; }
    .hero-start-btn { flex: 1; width: auto; min-height: 54px; font-size: 16px; padding: 12px 20px; }
    .start-cta-row { gap: 20px; } .start-cta-row .text-link { font-size: 11px; }
    .home-footer { font-size: 9px; flex-wrap: wrap; gap: 15px; padding-top: 17px; } .home-footer > p { display: none; }
    .home-footer-links { width: 100%; justify-content: space-between; } .home-footer-links > * { padding: 0 14px; } .home-footer-links > :first-child { padding-left: 0; border: 0; }
    .settings-modal-overlay, .lexicon-modal-overlay, .lexicon-detail-overlay, .help-overlay { padding: 12px; }
    .settings-modal-box, .lexicon-window { height: calc(100dvh - 24px); border-radius: 11px; }
    .settings-modal-header, .lexicon-header { padding: 18px 19px; } .settings-modal-title, .lexicon-title { font-size: 22px; }
    .settings-modal-body { display: flex; flex-direction: column; }
    .settings-sidebar-nav { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); flex-direction: row; padding: 10px 8px; border-right: 0; border-bottom: 1px solid var(--line-soft); gap: 2px; justify-content: space-between; flex-shrink: 0; }
    .settings-nav-btn { padding: 9px 2px; justify-content: center; } .settings-tab-panels { padding: 23px 19px; flex: 1; }
    .diff-top-letters-grid { grid-template-columns: repeat(2, 1fr); }
    .diff-slider-ticks { font-size: 11px; }
    .lang-setting-row { align-items: flex-start; flex-direction: column; gap: 14px; padding: 19px 0; }
    .lang-select-wrapper, .lang-segmented-control { width: 100%; } .lang-pill-btn { flex: 1; padding: 8px 10px; }
    .settings-modal-footer { flex-shrink: 0; padding: 14px 19px; } .settings-confirm-btn { padding: 10px 15px; }
    .syllabus-card-tag, .setting-title-line .setting-badge-tag { display: none; } .syllabus-card-title { gap: 6px; } .setting-title-line { gap: 5px; }
    .lexicon-title-group { width: 100%; } .lexicon-header { flex-wrap: wrap; } .lexicon-header-actions { width: 100%; justify-content: flex-end; gap: 7px; } #lexiconRandomBtn { padding: 6px 8px; min-height: 40px; }
    .lexicon-close-icon-btn { width: 36px; height: 36px; }
    .lexicon-toolbar { padding: 14px 19px; gap: 10px; max-height: 45dvh; overflow: auto; flex-shrink: 0; } .lexicon-match-pill, .filter-label, .len-count-badge { display: none; }
    .lexicon-search-input { font-size: 16px; } .lexicon-filter-group { gap: 7px; }
    .lex-len-pills-container { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 4px; width: 100%; } .lex-len-btn { padding: 5px 8px; }
    .lexicon-secondary-row { gap: 8px; } .lex-select { font-size: 16px; }
    .lexicon-scroll-body { padding: 0 19px 16px; } .lexicon-grid { grid-template-columns: 1fr; }
    .lexicon-word-card { padding: 12px 10px; } .lex-word-name { font-size: 25px; } .lex-card-meaning { min-height: 0; } .lex-card-footer { margin-top: 8px; }
    .lexicon-footer { flex-shrink: 0; padding: 12px 19px; } .lex-footer-tip { max-width: 55%; } .lex-confirm-btn { padding: 9px 14px; }
    .lexicon-detail-card { max-height: calc(100dvh - 24px); } .detail-content { padding: 22px 20px; } .detail-word-title { font-size: 34px; }
    .tetris-tile-preview { width: 32px; height: 37px; font-size: 21px; } .detail-stat-box { flex-direction: column; gap: 4px; } .nav-key-tip { display: none; }
    .help-window { padding: 22px; max-height: calc(100dvh - 24px); } .help-title { font-size: 25px; } .help-keys { gap: 9px; }
}
@media (max-width: 600px) {
    .help-body { grid-template-columns: 1fr; gap: 18px; }
    .help-guide { order: 1; }
    .help-demo { width: 100%; order: 0; }
    .help-header { position: sticky; top: 0; z-index: 3; margin: -22px -22px 20px; padding: 18px 22px; background: var(--surface); border-bottom: 1px solid var(--line-soft); }
    .help-demo-stage { width: min(230px, 100%); margin-inline: auto; }
    .help-demo-score { width: min(230px, 100%); margin-inline: auto; }
    .help-demo-progress { margin-top: 16px; }
    .help-keys { margin-bottom: 0; }
}
@media (max-width: 640px) and (max-height: 640px) {
    /* Keep word entries readable while the filters scroll independently. */
    .lexicon-toolbar { max-height: 30dvh; }
}
@media (max-width: 640px) and (max-height: 760px) {
    .home-shell { padding: 14px 20px 15px; }
    .home-topbar { min-height: 34px; }
    .home-body { padding: 14px 0 18px; }
    .hero-wordmark { display: flex; font-size: clamp(48px, 13vw, 72px); line-height: 1; padding-bottom: 0; }
    .hero-wordmark > span { display: inline; }
    .home-tagline { margin-top: 6px; font-size: 11px; }
    .letter-sculpture { height: clamp(120px, 28vh, 185px); margin: 4px 0 10px; }
    .mode-card { padding: 6px 0 8px; }
    .mode-caption { min-height: 18px; margin: 8px 0 12px; font-size: 10px; }
    .hero-start-btn { min-height: 48px; }
    .home-footer { padding-top: 12px; }
}
@media (max-width: 900px) and (max-height: 720px) {
    .left-sidebar { gap: 14px; }
    .score-group .sub-card { display: none; }
    .next-preview-card { padding: 12px 0; }
    .level-group { flex-direction: row; gap: 6px; }
    .level-group .stat-label { font-size: 7px; }
    .level-group .stat-value { font-size: 18px; }
}
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation: none !important; transition-duration: .01ms !important; scroll-behavior: auto !important; }
    .sculpture-parallax { transform: none; }
}