:root{--bg:#f6f7f9;--surface:#fff;--surface-2:#f0f2f5;--text:#1a1d23;--muted:#5f6672;--border:#dde1e7;--primary:#2563eb;--primary-hover:#1d4ed8;--primary-text:#fff;--primary-soft:#e8efff;--good:#15803d;--good-soft:#e7f6ec;--bad:#c62828;--bad-soft:#fdecec;--warn:#b45309;--warn-soft:#fef3e2;--shadow:0 1px 2px #1018280f, 0 1px 3px #10182814;--shadow-lg:0 12px 32px #1018282e, 0 2px 6px #1018281a;--radius:12px;--xp:#7c3aed;--xp-soft:#f1ebff;--flame:#c2410c;--flame-soft:#fff1e7;--ice:#0e7490;--ice-soft:#e4f6fa;--mastered:#0f6b32;--good-mid:#6fcf97;--header-h:57px;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;color:var(--text);background:var(--bg);-webkit-text-size-adjust:100%;-webkit-tap-highlight-color:transparent;font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;font-size:17px;line-height:1.5}@media (prefers-color-scheme:dark){:root{--bg:#14161a;--surface:#1d2026;--surface-2:#262a32;--text:#e8eaee;--muted:#9aa2ae;--border:#343944;--primary:#5b8cff;--primary-hover:#7aa2ff;--primary-text:#0b1020;--primary-soft:#1f2b47;--good:#4ade80;--good-soft:#15301f;--bad:#f87171;--bad-soft:#3a1c1c;--warn:#fbbf24;--warn-soft:#3a2c10;--shadow:none;--shadow-lg:0 12px 32px #0000008c;--xp:#b69cff;--xp-soft:#2b2342;--flame:#fb923c;--flame-soft:#3a2414;--ice:#67d4ea;--ice-soft:#12313a;--mastered:#86efac;--good-mid:#2f8a52;--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark}}*,:before,:after{box-sizing:border-box}html,body{background:var(--bg);min-height:100%;margin:0}h1,h2,h3{margin:0 0 .5rem;line-height:1.25}h1{font-size:1.5rem}h2{font-size:1.1rem}h3{font-size:1rem}p{margin:0 0 .75rem}a{color:var(--primary)}button,input,select{font:inherit;color:inherit}:focus-visible{outline:3px solid var(--primary);outline-offset:2px}.container{width:100%;max-width:720px;margin:0 auto;padding:0 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ease-out}.question-card{padding:18px 16px}.question-text{margin-bottom:.75rem;font-size:1.1rem;font-weight:600}.options{flex-direction:column;gap:10px;margin-top:12px;display:flex}.option{border:2px solid var(--border);background:var(--surface);cursor:pointer;-webkit-user-select:none;user-select:none;border-radius:12px;align-items:flex-start;gap:12px;min-height:56px;padding:12px 14px;display:flex;position:relative}.option:not(.option-readonly):hover{border-color:var(--muted)}.option input{opacity:0;pointer-events:none;width:1px;height:1px;position:absolute}.option:has(input:focus-visible){outline:3px solid var(--primary);outline-offset:2px}.option-letter{border:2px solid 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.option-mark{color:var(--bad)}.option-missed{border-color:var(--good);border-style:dashed}.option-missed .option-letter{border-color:var(--good);color:var(--good)}.option-missed .option-mark{color:var(--good)}.feedback{border-radius:10px;flex-wrap:wrap;align-items:baseline;gap:4px 8px;margin-top:16px;padding:12px 14px;font-size:1.05rem;display:flex}.feedback-correct{background:var(--good-soft);color:var(--good)}.feedback-wrong{background:var(--bad-soft);color:var(--bad)}.feedback-detail{color:var(--text);font-size:.95rem}.explanation{border-left:4px solid var(--primary);background:var(--surface-2);border-radius:0 10px 10px 0;margin-top:12px;padding:12px 14px}.explanation h3{margin-bottom:4px}.rich{white-space:pre-wrap;overflow-wrap:anywhere;overflow-x:auto}.rich p,.rich ul,.rich ol,.rich table{margin:0 0 .5em}.rich>:last-child{margin-bottom:0}.rich ul,.rich ol{padding-left:1.3em}.rich table{border-collapse:collapse;white-space:normal}.rich td,.rich th{border:1px solid 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.segmented{flex:100%}.segmented .segment{flex:1}.stat-value{font-size:1.3rem}.stats{gap:8px}}.sr-only{clip:rect(0 0 0 0);white-space:nowrap;border:0;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;position:absolute!important}.bar{background:var(--surface-2);border-radius:999px;height:8px;display:block;position:relative;overflow:hidden}.bar-sm{height:6px}.bar-fill{background:var(--primary);border-radius:999px;transition:transform .9s cubic-bezier(.22,1,.36,1);position:absolute;inset:0}.bar-xp .bar-fill{background:linear-gradient(90deg, color-mix(in srgb, var(--xp) 70%, var(--primary)), var(--xp))}.bar-mastery .bar-fill{background:var(--mastered)}.bar-mastery .bar-fill-seen{background:color-mix(in srgb, var(--good) 28%, var(--surface-2))}.meter-mastered{background:var(--mastered)}.meter>.meter-good{background:var(--good-mid)}.level{align-items:center;gap:12px;min-height:44px;display:flex}.level-skeleton{height:44px;margin:16px 0}.level-badge{background:linear-gradient(135deg, color-mix(in srgb, var(--xp) 75%, var(--primary)), var(--xp));color:#fff;font-variant-numeric:tabular-nums;border-radius:12px;flex-shrink:0;justify-content:center;align-items:center;width:40px;height:40px;font-size:1.05rem;font-weight:800;display:inline-flex;box-shadow:inset 0 -2px #00000026}.level-badge-sm{border-radius:8px;width:26px;height:26px;font-size:.78rem}.level-main{flex-direction:column;flex:1;gap:5px;min-width:0;display:flex}.level-head{justify-content:space-between;align-items:baseline;gap:8px;display:flex}.level-title{text-overflow:ellipsis;white-space:nowrap;min-width:0;font-weight:700;overflow:hidden}.level-xp{color:var(--xp);font-variant-numeric:tabular-nums;flex-shrink:0;font-size:.82rem;font-weight:700}.level-xp .muted{font-weight:600}.ring{flex-shrink:0;position:relative}.ring svg{display:block}.ring-track{stroke:var(--surface-2)}.ring-fill{stroke:var(--primary)}.ring-done .ring-fill{stroke:var(--good)}.ring-label{font-variant-numeric:tabular-nums;justify-content:center;align-items:baseline;padding-top:26px;line-height:1;display:flex;position:absolute;inset:0}.ring-value{font-size:1.35rem;font-weight:800}.ring-goal{color:var(--muted);font-size:.78rem;font-weight:600}.ring-check{color:var(--good);margin-top:-4px;font-size:1.6rem;font-weight:800}.hero{flex-direction:column;gap:14px;margin-bottom:12px;padding:16px;display:flex}.skeleton-card.hero{height:226px}.hero-countdown{background:var(--primary-soft);color:var(--primary);border-radius:999px;align-self:flex-start;margin:0;padding:4px 12px;font-size:.85rem;font-weight:700}.hero-main{align-items:center;gap:16px;display:flex}.hero-ring{color:inherit;border-radius:999px;flex-shrink:0;text-decoration:none}.hero-today{flex-direction:column;flex:1;gap:4px;min-width:0;display:flex}.hero-streak{flex-wrap:wrap;align-items:center;gap:6px 8px;display:flex}.hero-flame{font-size:1.35rem;line-height:1}.hero-streak-off .hero-flame{filter:grayscale();opacity:.55}.hero-streak-text{font-size:1.2rem;font-weight:800;line-height:1.2}.freeze-chip{background:var(--ice-soft);color:var(--ice);font-variant-numeric:tabular-nums;border-radius:999px;align-items:center;padding:1px 8px;font-size:.82rem;font-weight:700;display:inline-flex}.freeze-chip-off{background:var(--surface-2);color:var(--muted);filter:grayscale(.7)}.hero-goal{font-variant-numeric:tabular-nums;margin:0}.goal-done{color:var(--good);font-weight:700}.hero-best{margin:0}.at-risk{border-radius:var(--radius);background:var(--flame-soft);color:var(--text);align-items:baseline;gap:8px;margin:0 0 12px;padding:10px 14px;font-size:.92rem;display:flex}.cta-wrap{margin-bottom:24px}.cta-wrap .alert{margin-bottom:0}.btn-cta{text-align:left;width:100%;min-height:72px;box-shadow:0 6px 16px color-mix(in srgb, var(--primary) 30%, transparent);border-radius:14px;justify-content:space-between;gap:12px;padding:12px 18px}.btn-cta .icon{transition:transform .2s 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.goal-row{justify-content:space-between;align-items:center;gap:12px;display:flex}.goal-label{margin:0;font-size:1.05rem}.goal-setting .muted.small{margin:0}.goal-status{min-height:1.3em;margin:6px 0 0}.goal-status-error{color:var(--bad);font-size:.85rem}.stepper{border:1px solid var(--border);background:var(--surface-2);border-radius:999px;flex-shrink:0;align-items:center;display:inline-flex}.stepper-btn{width:44px;height:40px;color:var(--text);cursor:pointer;background:0 0;border:0;border-radius:999px;font-size:1.2rem;font-weight:700;line-height:1}.stepper-btn:disabled{opacity:.4;cursor:default}.stepper-btn:not(:disabled):hover{background:var(--border)}.stepper-value{text-align:center;font-variant-numeric:tabular-nums;min-width:2.4em;font-weight:800}.heatmap{gap:4px;display:flex}.heatmap-days,.heatmap-grid{margin:0;padding:0;list-style:none}.heatmap-days{color:var(--muted);grid-template-rows:repeat(7,1fr);gap:3px;font-size:.65rem;line-height:1;display:grid}.heatmap-days 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.hm-cell{width:11px;height:11px}.heatmap-skeleton{border-radius:8px;height:150px}.achievements{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;margin:0 0 24px;padding:0;list-style:none;display:grid}@media (width>=600px){.achievements{grid-template-columns:repeat(3,minmax(0,1fr))}}.ach{border-radius:var(--radius);background:var(--surface);border:1px solid var(--border);flex-direction:column;gap:2px;padding:12px;display:flex}.ach-on{border-color:color-mix(in srgb, var(--xp) 35%, var(--border));background:linear-gradient(160deg, var(--xp-soft), var(--surface) 65%)}.ach-icon{margin-bottom:4px;font-size:1.6rem;line-height:1.1}.ach-off .ach-icon{filter:grayscale();opacity:.45}.ach-title{font-weight:700;line-height:1.25}.ach-off .ach-title{color:var(--muted)}.ach-desc{color:var(--muted);font-size:.78rem;line-height:1.3}.ach-date{color:var(--xp);margin-top:auto;padding-top:6px;font-size:.75rem;font-weight:700}.ach-progress{align-items:center;gap:8px;margin-top:auto;padding-top:8px;display:flex}.ach-progress .bar{flex:1}.ach-progress .bar-fill{background:var(--muted)}.ach-count{color:var(--muted);font-variant-numeric:tabular-nums;font-size:.72rem;font-weight:700}.achievements-skeleton{height:260px;margin-bottom:24px}.mastery{margin-bottom:12px}.mastery-summary{cursor:pointer;flex-wrap:wrap;justify-content:space-between;align-items:baseline;gap:4px 12px;min-height:52px;padding:14px 16px;font-weight:700;list-style-position:inside;display:flex}.mastery-list{margin:0;padding:0 16px 12px;list-style:none}.mastery-row{border-top:1px solid var(--border);grid-template-columns:minmax(0,1fr) 72px auto;align-items:center;gap:10px;padding:6px 0;font-size:.88rem;display:grid}.mastery-name{text-overflow:ellipsis;white-space:nowrap;overflow:hidden}.mastery-count{text-align:right;font-variant-numeric:tabular-nums;min-width:4.5em}.account-saved{margin-bottom:24px}.saved-practice{margin-bottom:14px}.saved-list{flex-direction:column;gap:10px;margin:0;padding:0;list-style:none;display:flex}.saved-item{align-items:flex-start;gap:8px;padding:12px 4px 12px 16px;display:flex}.saved-main{flex-direction:column;flex:1;align-items:flex-start;gap:6px;min-width:0;display:flex}.saved-snippet{overflow-wrap:anywhere;margin:0;font-weight:600;line-height:1.4}@media (prefers-reduced-motion:reduce){*,:before,:after{transition:none!important;animation:none!important}}.show-all{width:100%;color:var(--primary);margin-top:6px}