:root{color-scheme:light;--color-bg: #f6f5f0;--color-surface: #ffffff;--color-surface-2: #f0efe8;--color-border: #e3e1d8;--color-border-strong: #c9cfc4;--color-text: #1d2a22;--color-muted: #5f6a62;--color-accent: #2f6b4a;--color-accent-fg: #ffffff;--color-accent-soft: #e4efe8;--color-success: #2f9a58;--color-success-soft: #dff3e6;--color-error: #c8433a;--color-error-soft: #fbe5e2;--color-warning: #9a6a10;--color-warning-soft: #fff2d6;--board-light: #ebe7d6;--board-dark: #86a37e;--board-highlight: rgba(246, 214, 88, .55);--board-last-move: rgba(246, 214, 88, .42);--board-correct: rgba(60, 190, 100, .55);--board-wrong: rgba(220, 70, 60, .55);--board-target: rgba(29, 42, 34, .35);--shadow-card: 0 1px 2px rgba(20,30,25,.06), 0 4px 14px rgba(20,30,25,.06);--color-backdrop: rgba(29, 42, 34, .55);--color-black: #000000;--color-transparent: transparent;--color-eval-white: #ffffff;--color-eval-black: #1d2a22;--app-bar-height: 56px;--board-size: min(100%, calc(100vh - var(--app-bar-height) - 150px), 600px);--space-1: 4px;--space-2: 8px;--space-3: 12px;--space-4: 16px;--space-5: 20px;--space-6: 24px;--space-7: 32px;--space-8: 48px;--radius-sm: 6px;--radius-md: 10px;--radius-lg: 14px;--font-sans: Inter, ui-sans-serif, system-ui, sans-serif;--font-mono: ui-monospace, SFMono-Regular, Menlo, monospace;--dark-color-bg: #121615;--dark-color-surface: #1b201f;--dark-color-surface-2: #232a28;--dark-color-border: #2c3532;--dark-color-border-strong: #3a4542;--dark-color-text: #e5ebe7;--dark-color-muted: #8f9c94;--dark-color-accent: #5bb184;--dark-color-accent-fg: #0d1a13;--dark-color-accent-soft: #1f3329;--dark-color-success: #4cc27a;--dark-color-success-soft: #173726;--dark-color-error: #ef6a5e;--dark-color-error-soft: #3a1f1c;--dark-color-warning: #e0b04a;--dark-color-warning-soft: #3a2f17;--dark-board-light: #c9c3ad;--dark-board-dark: #6c8a65;--dark-board-highlight: rgba(246, 214, 88, .45);--dark-board-last-move: rgba(246, 214, 88, .32);--dark-board-correct: rgba(60, 190, 100, 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var(--dark-board-light);--board-dark: var(--dark-board-dark);--board-highlight: var(--dark-board-highlight);--board-last-move: var(--dark-board-last-move);--board-correct: var(--dark-board-correct);--board-wrong: var(--dark-board-wrong);--board-target: var(--dark-board-target);--shadow-card: var(--dark-shadow-card);--color-backdrop: var(--dark-color-backdrop)}}:root[data-theme=dark]{color-scheme:dark;--color-bg: var(--dark-color-bg);--color-surface: var(--dark-color-surface);--color-surface-2: var(--dark-color-surface-2);--color-border: var(--dark-color-border);--color-border-strong: var(--dark-color-border-strong);--color-text: var(--dark-color-text);--color-muted: var(--dark-color-muted);--color-accent: var(--dark-color-accent);--color-accent-fg: var(--dark-color-accent-fg);--color-accent-soft: var(--dark-color-accent-soft);--color-success: var(--dark-color-success);--color-success-soft: var(--dark-color-success-soft);--color-error: var(--dark-color-error);--color-error-soft: var(--dark-color-error-soft);--color-warning: var(--dark-color-warning);--color-warning-soft: var(--dark-color-warning-soft);--board-light: var(--dark-board-light);--board-dark: var(--dark-board-dark);--board-highlight: var(--dark-board-highlight);--board-last-move: var(--dark-board-last-move);--board-correct: var(--dark-board-correct);--board-wrong: var(--dark-board-wrong);--board-target: var(--dark-board-target);--shadow-card: var(--dark-shadow-card);--color-backdrop: var(--dark-color-backdrop)}:root{font-family:var(--font-sans);color:var(--color-text);background:var(--color-bg);font-synthesis:none;text-rendering:optimizeLegibility}*{box-sizing:border-box}body{margin:0;min-width:320px;font:15px / 1.5 var(--font-sans);color:var(--color-text)}main{max-width:1200px;margin:0 auto;padding:var(--space-6)}h1{margin:var(--space-1) 0;font-size:1.75rem;letter-spacing:-.01em}h2{margin:0 0 var(--space-4);font-size:1.35rem;letter-spacing:-.01em}h3{margin:var(--space-4) 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srgb,var(--color-eval-white) 90%,var(--color-accent))}.today-continue:focus-visible{outline-color:var(--color-accent-fg)}.today-continue strong{font-size:1.25rem}.today-continue span{font-size:.85rem;font-weight:400}.today-cards{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:var(--space-4)}.today-line{display:flex;flex-wrap:wrap;align-items:center;gap:var(--space-4)}.today-line>div{flex:1;min-width:140px;overflow-wrap:anywhere}.today-line h4{margin:0}.today-mastery{margin:var(--space-3) 0;padding-left:var(--space-5);max-height:5rem;overflow-y:auto;font-size:.85rem}.today-mastery li{margin-bottom:var(--space-1)}.today-reviews{display:flex;flex-wrap:wrap;align-items:center;gap:var(--space-4)}.today-reviews h3,.today-reviews p{margin:0}.today-reviews button{margin-left:auto}@media(max-width:700px){.today-stats,.today-cards{grid-template-columns:minmax(0,1fr)}.today-hero{padding:var(--space-5)}}@media(min-width:901px){.game-layout>.board-panel{position:sticky;top:calc(var(--app-bar-height) + var(--space-4));width:var(--board-size);max-height:calc(100vh - var(--app-bar-height) - var(--space-6));overflow-y:auto}}@media(max-width:900px){.app-bar{gap:var(--space-2);padding:0 var(--space-4)}.app-bar nav{font-size:.9rem}.game-layout{grid-template-columns:minmax(0,1fr);gap:var(--space-4)}.move-list{max-height:240px}}@media(max-width:600px){main{padding:var(--space-4);padding-bottom:calc(56px + env(safe-area-inset-bottom) + var(--space-4))}.app-bar{padding:0 var(--space-4)}.app-bar nav{position:fixed;inset:auto 0 0;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:0;min-height:56px;padding-bottom:env(safe-area-inset-bottom);background:var(--color-surface);border-top:1px solid var(--color-border)}.app-bar nav button{min-height:56px;padding:var(--space-2) var(--space-1);border-radius:0}.app-utilities{gap:var(--space-1)}.stats-tiles{grid-template-columns:repeat(auto-fit,minmax(140px,1fr))}.board-panel{width:100%;max-width:none}.board-with-eval{position:relative;display:block}.board-with-eval .eval-bar{position:absolute;left:calc(-1 * var(--space-2));top:0;bottom:0;width:6px}button,input:not([type=radio]):not([type=checkbox]),select{min-height:44px}fieldset label,.course-choice{min-height:44px}}.line-progress{display:flex;align-items:center;gap:var(--space-3);margin-bottom:var(--space-3)}.line-progress progress{flex:1;min-width:0}.feedback-wrong,.feedback-success{padding:var(--space-3);border-radius:var(--radius-sm)}.feedback-wrong{background:var(--color-error-soft);border-left:4px solid var(--color-error)}.feedback-success{background:var(--color-success-soft);border-left:4px solid var(--color-success)}