*{box-sizing:border-box;margin:0;padding:0}:root{--blue: #1A4B8C;--blue-light: #EBF2FF;--blue-dark: #13387A;--gold: #C8A84E;--green: #16A34A;--green-light: #DCFCE7;--red: #DC2626;--red-light: #FEF2F2;--text: #0A1628;--text-secondary: #3D5478;--text-muted: #8FA3BF;--surface: #FFFFFF;--surface-2: #F2F5FA;--border: #DDE4EF;--shadow-sm: 0 1px 3px rgba(10,22,40,.06), 0 4px 12px rgba(10,22,40,.05);--shadow: 0 2px 8px rgba(10,22,40,.08), 0 8px 24px rgba(10,22,40,.08);--shadow-lg: 0 4px 16px rgba(10,22,40,.1), 0 16px 48px rgba(10,22,40,.12);--radius: 14px;--radius-sm: 10px;--radius-lg: 20px;--nav-height: 64px}[data-theme=dark]{--text: #E2EEFF;--text-secondary: #8AABCF;--text-muted: #5A7A9A;--surface: #0F1E35;--surface-2: #0A1628;--border: #1C334F;--blue-light: #0D2240;--green-light: #0A2A14;--red-light: #2A0A0A;--shadow-sm: 0 1px 3px rgba(0,0,0,.4), 0 4px 12px rgba(0,0,0,.3);--shadow: 0 2px 8px rgba(0,0,0,.5), 0 8px 24px rgba(0,0,0,.4)}[data-theme=dark] body,[data-theme=dark] .app-shell,[data-theme=dark] .page-content{background:#0a1628}[data-theme=dark] .bottom-nav{background:#0f1e35;box-shadow:0 -1px #ffffff0f,0 -8px 32px #0006}[data-theme=dark] .chapter-sticky-header{background:#0f1e35;border-color:#1c334f}[data-theme=dark] .quiz-option{background:#0f1e35;border-color:#1c334f;color:#e2eeff}[data-theme=dark] .quiz-option:hover:not(:disabled){background:#0d2240;border-color:var(--blue)}[data-theme=dark] .speed-table th{background:#0a1628;color:#8aabcf;border-color:#1c334f}[data-theme=dark] .speed-table td{color:#c8ddef;border-color:#1c334f}[data-theme=dark] .speed-table tr:hover td{background:#0d2240}[data-theme=dark] .btn-ghost{background:#0f1e35;border-color:#1c334f;color:#8aabcf}[data-theme=dark] .reading-content{color:#c8ddef}html{width:100%;height:100%;overflow-x:hidden;overflow-y:hidden;-webkit-text-size-adjust:100%;-moz-text-size-adjust:100%;text-size-adjust:100%}body{width:100%;height:100%;overflow-x:hidden;overflow-y:hidden;font-family:Plus Jakarta Sans,DM Sans,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;color:var(--text);background:var(--surface-2);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;letter-spacing:-.01em;overscroll-behavior:none;-webkit-overflow-scrolling:touch}#root{width:100%;height:100%;display:flex;flex-direction:column}.app-shell{display:flex;flex-direction:column;width:100%;height:100vh;height:-webkit-fill-available;height:100dvh;background:var(--surface-2);position:relative;overflow:hidden;padding-top:env(safe-area-inset-top,0px);padding-left:env(safe-area-inset-left,0px);padding-right:env(safe-area-inset-right,0px)}.content-area{flex:1;min-height:0;min-width:0;display:flex;flex-direction:column;overflow:hidden;position:relative}.nav-mobile-hidden{display:none!important}@media (min-width: 641px) and (max-width: 899px){.app-shell{max-width:640px;margin:0 auto;padding-left:0;padding-right:0}}@media (min-width: 900px){html,body{overflow:auto;overscroll-behavior:auto}#root{background:#0a1628;align-items:stretch}.app-shell{display:grid;grid-template-columns:220px 1fr;grid-template-rows:100dvh;max-width:1280px;width:100%;height:100vh;height:100dvh;margin:0 auto;padding:0;box-shadow:0 0 80px #0006;overflow:hidden}.content-area{grid-column:2;grid-row:1;height:100dvh;overflow:hidden}.nav-mobile-hidden{display:flex!important}.bottom-nav{grid-column:1;grid-row:1;width:220px;min-width:220px;height:100dvh;flex-direction:column;flex-shrink:0;box-shadow:1px 0 0 var(--border),2px 0 16px #0a16280f}[data-theme=dark] .bottom-nav{box-shadow:1px 0 #ffffff0f,2px 0 16px #0006}.bottom-nav:after{display:none}.nav-logo{display:flex!important}.nav-tabs{flex-direction:column;height:auto;flex:1;padding:12px;gap:2px;overflow-y:auto;align-items:stretch}.nav-tab{flex-direction:row;justify-content:flex-start;width:100%;padding:11px 14px;font-size:14px;font-weight:600;margin:0;border-radius:10px;gap:11px;min-height:44px;text-align:left;letter-spacing:-.1px}.page-content{padding-bottom:28px}.page{padding:0 32px}}.nav-logo{display:none;align-items:center;gap:10px;padding:20px 18px 16px;border-bottom:1px solid var(--border);color:var(--text);flex-shrink:0}img,svg{max-width:100%}button,a,[role=button]{touch-action:manipulation}input[type=email],input[type=password],input[type=text],input[type=number],select,textarea{font-size:16px!important}.page-content,.content-area{-webkit-overflow-scrolling:touch}.chapter-sticky-header{position:-webkit-sticky;position:sticky;top:0}@supports (-webkit-backdrop-filter: blur(8px)) or (backdrop-filter: blur(8px)){.app-shell{-webkit-backdrop-filter:none;backdrop-filter:none}}.nav-tab,.btn{-webkit-user-select:none;-moz-user-select:none;user-select:none}.page-content{flex:1;min-height:0;overflow-y:auto;overflow-x:hidden;-webkit-overflow-scrolling:touch;padding-bottom:calc(var(--nav-height) + env(safe-area-inset-bottom,0px) + 16px);scrollbar-width:thin;scrollbar-color:var(--border) transparent;background:var(--surface-2)}.page-content::-webkit-scrollbar{width:4px}.page-content::-webkit-scrollbar-track{background:transparent}.page-content::-webkit-scrollbar-thumb{background:var(--border);border-radius:2px}.page{width:100%;padding:0 16px}@media (min-width: 480px){.page{padding:0 20px}}.reading-section{transition:background .25s ease,border-color .25s ease,padding .25s ease}.reading-content{font-family:Plus Jakarta Sans,system-ui,sans-serif;font-size:16px;line-height:1.85;color:#2d3f5c;white-space:pre-line;overflow-wrap:break-word;word-break:break-word}.reading-content p{margin-bottom:16px}@media (max-width: 360px){.reading-content{font-size:15px;line-height:1.75}}.book-illustration-wrap{width:100%}.book-illustration{display:block;width:100%;height:auto;max-height:75vh;object-fit:contain;image-orientation:from-image;border-radius:12px;background:#fff;padding:10px;box-shadow:var(--shadow-sm);border:1px solid var(--border)}@media (max-width: 380px){.book-illustration{padding:6px}}.book-illustration-caption{display:block;text-align:center;font-size:12px;color:var(--text-muted);margin-top:8px;font-style:italic;line-height:1.5;padding:0 4px}.section-heading{font-family:Plus Jakarta Sans,system-ui,sans-serif;font-size:15px;font-weight:700;margin-bottom:10px;letter-spacing:-.1px}@media (max-width: 360px){.section-heading{font-size:14px}}.speed-table{width:100%;border-collapse:collapse;font-family:Plus Jakarta Sans,system-ui,sans-serif;font-size:13px;margin:4px 0;border-radius:var(--radius-sm);overflow:hidden}.speed-table th{background:var(--surface-2);color:var(--text-secondary);font-weight:700;text-align:left;padding:10px 12px;border-bottom:2px solid var(--border);font-size:11px;text-transform:uppercase;letter-spacing:.6px;white-space:nowrap}.speed-table td{padding:10px 12px;border-bottom:1px solid #EEF2F8;color:#334155}.speed-table tr:last-child td{border-bottom:none}.speed-table tr:hover td{background:#f8fafd}@media (max-width: 380px){.speed-table{font-size:11px}.speed-table th,.speed-table td{padding:8px}}.book-card{background:var(--surface);border-radius:var(--radius-lg);padding:16px;margin-bottom:12px;cursor:pointer;box-shadow:var(--shadow-sm);transition:box-shadow .18s ease,transform .18s ease;-webkit-tap-highlight-color:transparent;width:100%;min-width:0}.book-card:active{transform:scale(.985)}.chapter-card{background:transparent;padding:14px 0;margin-bottom:0;cursor:pointer;display:flex;align-items:center;justify-content:space-between;transition:opacity .15s ease;-webkit-tap-highlight-color:transparent;min-height:56px;width:100%;min-width:0;border-bottom:1px solid var(--border)}.chapter-card:active{opacity:.65}.btn{border-radius:var(--radius-sm);padding:13px 18px;font-weight:700;font-size:14px;cursor:pointer;font-family:Plus Jakarta Sans,system-ui,sans-serif;letter-spacing:-.1px;transition:all .15s ease;border:none;min-height:50px;display:inline-flex;align-items:center;justify-content:center;gap:6px;-webkit-tap-highlight-color:transparent;touch-action:manipulation}.btn-primary{background:var(--blue);color:#fff;box-shadow:0 3px 12px #1a4b8c59}.btn-primary:hover{background:var(--blue-dark)}.btn-primary:active{transform:scale(.97);box-shadow:0 1px 6px #1a4b8c40}.btn-outline{background:var(--surface);color:var(--blue);border:2px solid var(--blue)}.btn-outline:hover{background:var(--blue-light)}.btn-ghost{background:var(--surface);color:var(--text-secondary);border:1.5px solid var(--border);box-shadow:var(--shadow-sm)}.btn-ghost:hover{background:var(--surface-2)}.btn-ghost:active{transform:scale(.97)}.bottom-nav{position:relative;height:calc(var(--nav-height) + env(safe-area-inset-bottom,0px));background:var(--surface);box-shadow:0 -1px #0000000f,0 -8px 32px #0a162814;display:flex;flex-direction:column;flex-shrink:0;z-index:100;width:100%}.nav-tabs{display:flex;width:100%;height:var(--nav-height);position:relative;padding:0 4px}.nav-tab{flex:1;min-width:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:3px;cursor:pointer;border:none;background:transparent;color:var(--text-muted);font-family:Plus Jakarta Sans,system-ui,sans-serif;font-size:10px;font-weight:600;letter-spacing:.1px;transition:color .2s ease,background-color .2s ease;min-height:48px;padding:6px 4px;-webkit-tap-highlight-color:transparent;touch-action:manipulation;position:relative;z-index:2;border-radius:12px;margin:6px 2px 0}.nav-tab.active{color:var(--blue);background:var(--blue-light)}.nav-indicator{display:none}.bottom-nav:after{content:"";display:block;height:env(safe-area-inset-bottom,0px);background:var(--surface);width:100%}.reading-progress-bar{width:100%;height:3px;background:var(--border);flex-shrink:0;position:relative;z-index:10}.reading-progress-fill{height:100%;border-radius:0 2px 2px 0;transition:width .1s linear}.chapter-sticky-header{position:relative;z-index:50;background:var(--surface);border-bottom:1px solid var(--border);padding:10px 16px;display:flex;align-items:center;gap:10px;box-shadow:0 2px 12px #0a16280f;flex-shrink:0;min-height:56px}.quiz-option{width:100%;text-align:left;background:var(--surface);border:2px solid var(--border);border-radius:var(--radius-sm);padding:14px 16px;color:var(--text);font-size:15px;cursor:pointer;font-family:Plus Jakarta Sans,system-ui,sans-serif;display:flex;align-items:center;gap:12px;line-height:1.45;transition:all .15s ease;min-height:56px;touch-action:manipulation;-webkit-tap-highlight-color:transparent;box-shadow:var(--shadow-sm);font-weight:500}.quiz-option:hover:not(:disabled){border-color:var(--blue);background:var(--blue-light);box-shadow:0 2px 8px #1a4b8c1f}.quiz-option.correct{background:var(--green-light);border-color:var(--green);color:#14532d}.quiz-option.wrong{background:var(--red-light);border-color:var(--red);color:#7f1d1d}.quiz-option.reveal{background:#f0fdf4;border-color:var(--green);color:#14532d}.quiz-option .label{width:30px;height:30px;min-width:30px;border-radius:8px;background:var(--surface-2);display:flex;align-items:center;justify-content:center;font-weight:700;font-size:13px;flex-shrink:0;color:var(--text-secondary);font-family:Plus Jakarta Sans,system-ui,sans-serif;border:1.5px solid var(--border)}@media (max-width: 360px){.quiz-option{font-size:14px;padding:11px 12px;gap:10px}}.stat-card{background:var(--surface);border-radius:var(--radius);padding:16px;box-shadow:var(--shadow-sm);display:flex;flex-direction:column;gap:4px}.placeholder-screen{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:60px 24px;text-align:center;gap:16px;min-height:60vh}.placeholder-icon{width:72px;height:72px;border-radius:var(--radius-lg);background:var(--blue-light);display:flex;align-items:center;justify-content:center;color:var(--blue);font-size:32px;margin-bottom:8px}::-webkit-scrollbar{width:4px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:2px}