:root{--text:#6b6375;--text-h:#08060d;--bg:#fff;--border:#e5e4e7;--code-bg:#f4f3ec;--accent:#aa3bff;--accent-bg:#aa3bff1a;--accent-border:#aa3bff80;--social-bg:#f4f3ec80;--shadow:#0000001a 0 10px 15px -3px, #0000000d 0 4px 6px -2px;--sans:system-ui, "Segoe UI", Roboto, sans-serif;--heading:system-ui, "Segoe UI", Roboto, sans-serif;--mono:ui-monospace, Consolas, monospace;font:18px/145% var(--sans);letter-spacing:.18px;--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light dark;color:var(--text);background:var(--bg);font-synthesis:none;text-rendering:optimizelegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}@media (prefers-color-scheme:dark){:root{--lightningcss-light: ;--lightningcss-dark:initial}}@media (width<=1024px){:root{font-size:16px}}@media (prefers-color-scheme:dark){:root{--text:#9ca3af;--text-h:#f3f4f6;--bg:#16171d;--border:#2e303a;--code-bg:#1f2028;--accent:#c084fc;--accent-bg:#c084fc26;--accent-border:#c084fc80;--social-bg:#2f303a80;--shadow:#0006 0 10px 15px -3px, #00000040 0 4px 6px -2px}#social .button-icon{filter:invert()brightness(2)}}body{margin:0}#root{box-sizing:border-box;flex-direction:column;width:100%;min-height:100svh;display:flex}button,input{font:inherit}h1,h2{font-family:var(--heading);color:var(--text-h);font-weight:500}h1{letter-spacing:-1.68px;margin:32px 0;font-size:56px}@media (width<=1024px){h1{margin:20px 0;font-size:36px}}h2{letter-spacing:-.24px;margin:0 0 8px;font-size:24px;line-height:118%}@media (width<=1024px){h2{font-size:20px}}p{margin:0}code,.counter{font-family:var(--mono);color:var(--text-h);border-radius:4px;display:inline-flex}code{background:var(--code-bg);padding:4px 8px;font-size:15px;line-height:135%}.app-shell{text-align:left;width:100%;min-height:100svh;display:flex}.app-sidebar{border-right:1px solid var(--border);box-sizing:border-box;flex-direction:column;flex-shrink:0;width:220px;padding:20px 16px;display:flex}.app-logo{color:var(--text-h);margin-bottom:24px;padding:0 8px;font-size:18px;font-weight:600}.app-nav{flex-direction:column;flex-grow:1;gap:4px;display:flex}.app-nav-link{color:var(--text);border-radius:8px;padding:10px 12px;font-size:15px;text-decoration:none;display:block}.app-nav-link:hover{background:var(--code-bg)}.app-nav-link.active{background:var(--accent-bg);color:var(--accent);font-weight:600}.app-sidebar-footer{border-top:1px solid var(--border);padding-top:12px}.app-user{color:var(--text-h);padding:0 12px 8px;font-size:14px;font-weight:600}.app-logout{text-align:left;cursor:pointer;background:0 0;border:none;width:100%}.app-main{flex-grow:1;min-width:0}.app-content{box-sizing:border-box;max-width:960px;margin:0 auto;padding:32px 40px}@media (width<=768px){.app-shell{flex-direction:column}.app-sidebar{border-right:none;border-bottom:1px solid var(--border);flex-flow:wrap;align-items:center;width:100%}.app-nav{flex-flow:wrap}.app-sidebar-footer{border-top:none;padding-top:0}.app-content{padding:20px}}.ui-card{background:var(--bg);border:1px solid var(--border);box-sizing:border-box;border-radius:12px;padding:20px}.question-card{background:var(--bg);border:1px solid var(--border);box-sizing:border-box;border-radius:12px;padding:24px}.question-text{margin-bottom:20px;font-size:18px}.question-choices{flex-direction:column;gap:10px;display:flex}.choice-btn{text-align:left;border:1px solid var(--border);background:var(--bg);color:var(--text);cursor:pointer;border-radius:8px;padding:12px 14px;font-size:15px}.choice-btn:hover:not(:disabled){border-color:var(--accent-border)}.choice-btn.selected{border-color:var(--accent);background:var(--accent-bg)}.choice-btn.correct{background:#2ecc711f;border-color:#2ecc71}.choice-btn.wrong{background:#e74c3c1f;border-color:#e74c3c}.choice-btn:disabled{cursor:default}.question-actions{text-align:center;margin-top:24px}.primary-btn{background:var(--accent);color:#fff;cursor:pointer;border:none;border-radius:8px;padding:10px 24px;font-size:15px}.primary-btn:disabled{opacity:.5;cursor:default}.question-explanation{background:var(--code-bg);border-left:4px solid var(--accent);border-radius:6px;margin-top:20px;padding:14px 16px;font-size:14px}.question-explanation p{color:var(--text);margin-top:8px}.ui-progress-label{color:var(--text);justify-content:space-between;margin-bottom:6px;font-size:14px;display:flex}.ui-progress-track{background:var(--code-bg);border-radius:999px;height:8px;overflow:hidden}.ui-progress-fill{background:var(--accent);border-radius:999px;height:100%;transition:width .3s}.page-title{margin:0 0 8px;font-size:26px}.page-desc{color:var(--text);font-size:15px}.subject-grid{grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:16px;margin-top:20px;display:grid}.subject-link{color:inherit;text-decoration:none}.subject-session{color:var(--accent);margin-bottom:6px;font-size:12px;font-weight:600}.subject-name{color:var(--text-h);font-size:16px;font-weight:600}.subject-count{color:var(--text);margin-top:8px;font-size:13px}.note-list{flex-direction:column;gap:14px;margin-top:16px;display:flex}.note-meta{color:var(--text);flex-wrap:wrap;gap:12px;margin-bottom:8px;font-size:13px;display:flex}.note-question{color:var(--text-h);font-size:15px;font-weight:500}.note-link{margin-top:12px;text-decoration:none;display:inline-block}.study-section{margin-top:28px}.study-section-title{margin-bottom:12px;font-size:18px}.auth-page{max-width:360px;margin:0 auto}.auth-card{margin-top:16px}.auth-form{flex-direction:column;gap:14px;display:flex}.auth-form label{color:var(--text);text-align:left;flex-direction:column;gap:6px;font-size:14px;display:flex}.auth-form input{border:1px solid var(--border);background:var(--bg);color:var(--text-h);border-radius:8px;padding:10px 12px}.form-error{color:#c0392b;background:#e74c3c1f;border:1px solid #e74c3c66;border-radius:8px;margin:0;padding:10px 12px;font-size:14px}.login-notice{border:1px solid var(--border);background:var(--code-bg);border-radius:10px;margin-top:20px;padding:14px 16px;font-size:14px}