*{box-sizing:border-box;margin:0;padding:0}:root,[data-theme=dark]{--bg:#0a0f1e;--surface:#141b2d;--surface2:#1e2940;--border:#2a3550;--gold:#f5a623;--gold-dim:#b8791a;--text:#fff;--text2:#8a9bb8;--text3:#4a5568;--correct:#22c55e;--incorrect:#ef4444;--warning:#f59e0b;--blue:#3b82f6;--purple:#8b5cf6;--orange:#f97316;--green:#10b981;--shadow:#00000080;--app-zoom:1}[data-theme=light]{--bg:#f0f4fa;--surface:#fff;--surface2:#e8edf7;--border:#c8d4e8;--gold:#d4830a;--gold-dim:#a86208;--text:#0a0f1e;--text2:#4a5a78;--text3:#8a9bb8;--correct:#16a34a;--incorrect:#dc2626;--warning:#d97706;--blue:#2563eb;--purple:#7c3aed;--orange:#ea6200;--green:#059669;--shadow:#00000026}[data-theme=light] html,[data-theme=light] body,[data-theme=light] #root{background-color:#f0f4fa}html{background-color:var(--bg);background:var(--bg);min-height:100%}body{background-color:var(--bg);background:var(--bg);min-height:100dvh;color:var(--text);-webkit-font-smoothing:antialiased;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;overflow-x:hidden}#root{background-color:var(--bg);background:var(--bg);min-height:100dvh}.app-shell{zoom:var(--app-zoom,1);background:var(--bg);min-height:100dvh;display:flex}.main-content{flex-direction:column;flex:1;min-width:0;display:flex}.app{background:var(--bg);flex:1;width:100%;max-width:520px;position:relative}.sidebar-nav{display:none}@media (width>=768px){.app-shell{max-width:1280px;margin:0 auto}.sidebar-nav{background:var(--surface);border-right:1px solid var(--border);flex-direction:column;flex-shrink:0;gap:2px;width:230px;height:100dvh;min-height:100dvh;padding:28px 14px 24px;display:flex;position:sticky;top:0;overflow-y:auto}.sidebar-logo{border-bottom:1px solid var(--border);align-items:center;gap:10px;margin-bottom:16px;padding:0 8px 24px;display:flex}.sidebar-section-label{color:var(--text3);text-transform:uppercase;letter-spacing:1px;margin-bottom:6px;padding:0 10px;font-size:10px;font-weight:700}.sidebar-btn{width:100%;color:var(--text2);cursor:pointer;text-align:left;background:0 0;border:none;border-radius:10px;align-items:center;gap:10px;padding:10px 12px;font-size:14px;font-weight:500;transition:background .15s,color .15s;display:flex}.sidebar-btn:hover{background:var(--surface2);color:var(--text)}.sidebar-btn.active{color:var(--gold);background:#f5a6231f;font-weight:700}.sidebar-icon{flex-shrink:0;justify-content:center;align-items:center;width:20px;height:20px;display:flex}.sidebar-icon svg{width:20px;height:20px}.tab-bar{display:none}.main-content{align-items:flex-start;padding:0 24px}.app{max-width:720px;padding-bottom:40px}.screen{padding:36px 0 60px}}.tab-bar{background:var(--surface);border-top:1px solid var(--border);z-index:100;width:100%;padding-bottom:env(safe-area-inset-bottom);display:flex;position:fixed;bottom:0;left:0;right:0}.tab-btn{cursor:pointer;color:var(--text2);background:0 0;border:none;flex-direction:column;flex:1;justify-content:center;align-items:center;gap:3px;padding:10px 0 8px;font-size:11px;font-weight:500;transition:color .15s;display:flex}.tab-btn.active{color:var(--gold)}.tab-btn svg{width:22px;height:22px}.screen{padding:24px 20px 100px;padding-top:max(24px, env(safe-area-inset-top,24px))}.card{background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:16px}.btn-gold{background:var(--gold);color:#fff;cursor:pointer;border:none;border-radius:14px;justify-content:center;align-items:center;gap:8px;width:100%;padding:15px 20px;font-size:16px;font-weight:700;transition:opacity .15s;display:flex}.btn-gold:active{opacity:.85}.btn-outline{color:var(--text2);border:1px solid var(--border);cursor:pointer;background:0 0;border-radius:12px;padding:12px 16px;font-size:14px;font-weight:600;transition:border-color .15s,color .15s}.btn-outline:hover{border-color:var(--gold);color:var(--gold)}h1{color:var(--text);margin-bottom:20px;font-size:28px;font-weight:700}h2{color:var(--text);margin-bottom:12px;font-size:18px;font-weight:700}.progress-bg{background:var(--surface2);border-radius:2px;height:4px}.progress-fill{background:var(--gold);border-radius:2px;height:4px;transition:width .3s}.chip{border-radius:20px;align-items:center;gap:5px;padding:4px 10px;font-size:12px;font-weight:600;display:inline-flex}.chip-blue{color:#3b82f6;background:#3b82f626;border:1px solid #3b82f64d}.chip-red{color:#fff;background:#dc2626}.option-btn{background:var(--surface);border:1px solid var(--border);cursor:pointer;text-align:left;width:100%;color:var(--text);border-radius:12px;align-items:center;gap:12px;padding:14px;font-size:15px;line-height:1.4;transition:border-color .1s,background .1s;display:flex}.option-btn:active:not(:disabled){opacity:.8}.option-btn.correct{border-color:var(--correct);background:#22c55e1f}.option-btn.incorrect{border-color:var(--incorrect);background:#ef44441f}.option-btn.correct span.text{color:var(--correct);font-weight:600}.option-btn.incorrect span.text{color:var(--incorrect)}.option-letter{background:var(--surface2);width:28px;height:28px;color:var(--text2);border-radius:14px;flex-shrink:0;justify-content:center;align-items:center;font-size:13px;font-weight:700;display:flex}.explanation{background:var(--surface2);border-left:3px solid var(--gold);border-radius:14px;padding:16px}.explanation-title{color:var(--gold);margin-bottom:6px;font-size:13px;font-weight:700}.explanation-text{color:var(--text2);font-size:14px;line-height:1.5}.source-ref{color:var(--text3);margin-top:8px;font-size:12px;font-style:italic}.stat-bar-bg{background:var(--surface2);border-radius:4px;height:8px;overflow:hidden}.stat-bar-fill{border-radius:4px;height:8px;transition:width .6s}::-webkit-scrollbar{width:4px}::-webkit-scrollbar-track{background:0 0}::-webkit-scrollbar-thumb{background:var(--border);border-radius:2px}@supports (padding:env(safe-area-inset-bottom)){.screen{padding-bottom:calc(100px + env(safe-area-inset-bottom))}}@media (width>=768px){.a11y-widget{flex-direction:row!important;gap:6px!important;bottom:20px!important;right:20px!important}}.home-cards-grid{flex-direction:column;gap:10px;margin-bottom:4px;display:flex}.home-card-active{transition:transform .12s,box-shadow .12s}.home-card-active:hover{transform:translateY(-2px);box-shadow:0 8px 24px #0000004d}@media (width>=768px){.home-cards-grid{grid-template-columns:1fr 1fr;gap:14px;display:grid}}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.fade-in{animation:.2s fadeIn}