:root{--bg-dark: #0b0c1a;--bg-darker: #06070d;--text-primary: #f0f0f5;--text-secondary: #a0a5b5;--accent-cyan: #00e5ff;--accent-teal: #1de9b6;--accent-magenta: #ff4081;--accent-purple: #d500f9;--accent-paper1: #ffb74d;--accent-paper2: #29b6f6;--glass-bg: rgba(255, 255, 255, .04);--glass-border: rgba(255, 255, 255, .08);--glass-hover: rgba(255, 255, 255, .08);--font-family: "Inter", sans-serif}*{box-sizing:border-box;margin:0;padding:0}body{font-family:var(--font-family);background:radial-gradient(circle at top left,#121429,var(--bg-darker));color:var(--text-primary);min-height:100vh;overflow:hidden;position:relative}body:before{content:"";position:absolute;top:0;left:0;right:0;bottom:0;background-image:radial-gradient(circle at 15% 50%,rgba(0,229,255,.03) 0%,transparent 50%),radial-gradient(circle at 85% 30%,rgba(255,64,129,.03) 0%,transparent 50%);z-index:-1;pointer-events:none}a{text-decoration:none;color:inherit}#app{display:flex;height:100vh}.sidebar{width:260px;background:#0a0b1899;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-right:1px solid var(--glass-border);display:flex;flex-direction:column;padding:1.5rem 1rem;z-index:10;transition:transform .3s ease,width .3s ease,padding .3s ease}.sidebar.hidden{transform:translate(-100%);width:0;padding:0;border:none;overflow:hidden}.logo{display:flex;align-items:center;gap:.75rem;font-size:1.25rem;font-weight:800;color:#fff;margin-bottom:2.5rem;padding:0 .5rem}.logo-icon{background:linear-gradient(135deg,var(--accent-cyan),var(--accent-purple));-webkit-background-clip:text;-webkit-text-fill-color:transparent}.nav-section{margin-bottom:1.5rem}.nav-item{display:flex;align-items:center;padding:.75rem 1rem;border-radius:8px;cursor:pointer;transition:all .2s ease;color:var(--text-secondary);font-weight:500;margin-bottom:.25rem}.nav-item:hover{background:var(--glass-hover);color:var(--text-primary)}.nav-item.active{background:#00e5ff1a;color:var(--accent-cyan);border-left:3px solid var(--accent-cyan)}.nav-icon{margin-right:1rem;font-size:1.2rem}.main-wrapper{flex:1;display:flex;flex-direction:column;overflow:hidden}.topbar{height:70px;display:flex;justify-content:space-between;align-items:center;padding:0 2rem;background:#0a0b1866;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-bottom:1px solid var(--glass-border)}.topbar-title{font-size:1.1rem;font-weight:600;letter-spacing:.5px}.topbar-actions{display:flex;align-items:center;gap:1.5rem}.user-profile{display:flex;align-items:center;gap:.75rem;background:var(--glass-bg);padding:.4rem 1rem .4rem .4rem;border-radius:20px;border:1px solid var(--glass-border)}.avatar{width:32px;height:32px;border-radius:50%;background:linear-gradient(135deg,var(--accent-paper1),var(--accent-magenta));display:flex;align-items:center;justify-content:center;font-weight:700;font-size:.9rem}.content-area{flex:1;overflow-y:auto;padding:2rem}.welcome-section{display:flex;justify-content:space-between;align-items:flex-start;margin-bottom:2.5rem}.welcome-text h1{font-size:2rem;margin-bottom:.5rem}.welcome-text p{color:var(--text-secondary)}.stats-container{display:flex;gap:1rem}.stat-card{background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:12px;padding:1rem 1.5rem;min-width:140px;box-shadow:0 4px 20px #0003}.stat-label{font-size:.85rem;color:var(--text-secondary);margin-bottom:.5rem}.stat-value{font-size:1.75rem;font-weight:700}.stat-value.cyan{color:var(--accent-cyan)}.stat-value.magenta{color:var(--accent-magenta)}.section-heading{font-size:1.25rem;font-weight:600;margin-bottom:1.5rem;margin-top:1rem;padding-bottom:.5rem;border-bottom:1px solid var(--glass-border)}.cards-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:1.5rem;margin-bottom:3rem}.subject-card{background:linear-gradient(180deg,#ffffff0d,#ffffff03);border:1px solid var(--glass-border);border-radius:16px;padding:1.5rem;transition:all .3s ease;display:flex;flex-direction:column;cursor:pointer;position:relative;overflow:hidden}.subject-card:hover{transform:translateY(-5px);border-color:#fff3;box-shadow:0 10px 30px #0006}.card-header{display:flex;align-items:center;gap:1rem;margin-bottom:1rem}.card-icon{width:48px;height:48px;border-radius:12px;display:flex;align-items:center;justify-content:center;font-size:1.5rem;background:#ffffff0d}.card-title{font-size:1.1rem;font-weight:600}.card-desc{font-size:.85rem;color:var(--text-secondary);margin-bottom:1.5rem;flex:1;line-height:1.5}.card-meta{font-size:.8rem;color:var(--text-secondary);display:flex;justify-content:space-between;margin-bottom:.75rem}.progress-track{height:6px;background:#0000004d;border-radius:3px;overflow:hidden;margin-bottom:1.5rem}.progress-fill{height:100%;border-radius:3px;transition:width .5s ease-out}.btn-explore{background:#ffffff0d;border:1px solid rgba(255,255,255,.1);color:var(--text-primary);padding:.75rem;border-radius:8px;font-weight:600;font-size:.9rem;text-align:center;transition:all .2s}.subject-card:hover .btn-explore{background:#ffffff26}.breadcrumb{display:flex;gap:.5rem;font-size:.9rem;color:var(--text-secondary);margin-bottom:2rem}.breadcrumb a{cursor:pointer}.breadcrumb a:hover{color:var(--text-primary)}.subject-hero{display:flex;align-items:center;gap:2rem;background:var(--glass-bg);border:1px solid var(--glass-border);padding:2rem;border-radius:16px;margin-bottom:2rem}.hero-icon{width:80px;height:80px;border-radius:20px;font-size:2.5rem;display:flex;align-items:center;justify-content:center;background:#ffffff0d}.hero-details h1{font-size:2rem;margin-bottom:.5rem}.hero-details p{color:var(--text-secondary);margin-bottom:1rem}.overall-progress{display:flex;align-items:center;gap:1rem}.overall-progress .progress-track{width:200px;margin:0}.topics-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(400px,1fr));gap:1.5rem}.topic-card{background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:16px;padding:1.5rem;display:flex;flex-direction:column;position:relative;overflow:hidden;box-shadow:0 4px 20px #00000026;transition:transform .2s,box-shadow .2s}.topic-card:hover{transform:translateY(-3px);box-shadow:0 8px 30px #0006;border-color:#ffffff26}.topic-card-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:.8rem}.topic-card-title{font-size:1.15rem;font-weight:600;color:var(--text-primary)}.topic-card-meta{font-size:.8rem;color:var(--text-secondary);background:#ffffff14;padding:.3rem .75rem;border-radius:20px;font-weight:500}.topic-card-content{display:flex;flex-direction:column;gap:.5rem;margin-top:.5rem}.subtopic-item{display:flex;align-items:flex-start;gap:1rem;padding:.75rem 0;border-bottom:1px solid rgba(255,255,255,.05)}.subtopic-item:last-child{border-bottom:none}.custom-checkbox{width:20px;height:20px;border:2px solid var(--text-secondary);border-radius:4px;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all .2s;flex-shrink:0;margin-top:2px}.custom-checkbox.checked{background:var(--accent-cyan);border-color:var(--accent-cyan)}.custom-checkbox.checked:after{content:"✓";color:#000;font-size:14px;font-weight:700}.subtopic-label{cursor:pointer;line-height:1.4;color:var(--text-primary);transition:color .2s}.subtopic-item.completed .subtopic-label{color:var(--text-secondary);text-decoration:line-through}.fade-in{animation:fadeIn .3s ease-in-out}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.btn-action{background:#ffffff14;border:1px solid rgba(255,255,255,.15);color:var(--text-primary);padding:.3rem .6rem;border-radius:6px;font-size:.75rem;cursor:pointer;transition:all .2s}.btn-action:hover{background:#ffffff26;transform:translateY(-1px)}.notes-container{background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:16px;padding:2rem;margin-top:1rem}.notes-header{display:flex;justify-content:space-between;align-items:center;border-bottom:1px solid var(--glass-border);padding-bottom:1rem;margin-bottom:2rem}.lang-toggle{display:flex;background:#0000004d;border-radius:8px;overflow:hidden}.lang-toggle button{background:none;border:none;color:var(--text-secondary);padding:.5rem 1rem;cursor:pointer;font-weight:600;transition:all .2s}.lang-toggle button.active{background:var(--accent-cyan);color:#000}.markdown-style{line-height:1.8;font-size:1.05rem}.markdown-style h1{color:var(--accent-cyan);margin-bottom:1rem;font-size:1.8rem}.markdown-style h2{color:var(--accent-paper1);margin-top:1.5rem;margin-bottom:.75rem}.markdown-style h3{color:var(--accent-paper2);margin-top:1.25rem;margin-bottom:.5rem}.markdown-style p{margin-bottom:1rem}.markdown-style ul,.markdown-style ol{margin-left:1.5rem;margin-bottom:1rem}.markdown-style li{margin-bottom:.5rem}.markdown-style strong{color:#fff}.notes-footer{margin-top:3rem;padding-top:1.5rem;border-top:1px solid var(--glass-border);text-align:center}.mcq-container{max-width:800px;margin:2rem auto;background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:16px;padding:2rem}.mcq-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:2rem;font-weight:600;color:var(--text-secondary)}.mcq-score{color:var(--accent-cyan);font-size:1.1rem}.mcq-question{font-size:1.3rem;font-weight:600;margin-bottom:2rem;line-height:1.5}.mcq-options-list{display:flex;flex-direction:column;gap:1rem;margin-bottom:2rem}.mcq-option{display:flex;align-items:center;gap:1rem;padding:1rem;background:#ffffff08;border:1px solid var(--glass-border);border-radius:10px;cursor:pointer;transition:all .2s}.mcq-option:hover{background:#ffffff14}.mcq-option.selected{border-color:var(--text-secondary);background:#ffffff1a}.mcq-option.correct{background:#2e7d324d;border-color:#4caf50}.mcq-option.wrong{background:#c628284d;border-color:#f44336}.mcq-letter{display:flex;align-items:center;justify-content:center;width:30px;height:30px;background:#ffffff1a;border-radius:50%;font-weight:700}.mcq-option.correct .mcq-letter{background:#4caf50;color:#fff}.mcq-option.wrong .mcq-letter{background:#f44336;color:#fff}.mcq-explanation{background:#ffffff0d;border-left:4px solid var(--accent-paper1);padding:1rem;margin-bottom:2rem;border-radius:0 8px 8px 0;line-height:1.6}.mcq-footer{display:flex;justify-content:flex-end}.mcq-results{text-align:center;padding:2rem}.result-circle{width:200px;height:200px;border-radius:50%;border:8px solid var(--accent-cyan);display:flex;flex-direction:column;align-items:center;justify-content:center;margin:2rem auto;background:#00e5ff0d}.score-big{font-size:2.5rem;font-weight:700;color:#fff}.percentage{font-size:1.5rem;color:var(--accent-cyan)}.mobile-overlay{display:none;position:fixed;top:0;left:0;right:0;bottom:0;background:#00000080;-webkit-backdrop-filter:blur(5px);backdrop-filter:blur(5px);z-index:9}.mobile-overlay.active{display:block}@media (max-width: 768px){.mobile-menu-icon{display:block!important}.sidebar{position:fixed;top:0;left:0;bottom:0;transform:translate(-100%);width:260px;z-index:100}.sidebar.mobile-open{transform:translate(0);box-shadow:4px 0 20px #00000080}.topbar{padding:0 1rem}.topbar-title{font-size:.9rem;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:150px}.user-profile span{display:none}.content-area{padding:1rem}.cards-grid,.topics-grid{grid-template-columns:1fr}.subject-hero{flex-direction:column;text-align:center;gap:1rem;padding:1.5rem}.overall-progress{flex-direction:column}.overall-progress .progress-track{width:100%}.lang-toggle{flex-direction:row;width:100%;margin-top:1rem}.notes-header{flex-direction:column;align-items:flex-start}.notes-header>div:last-child{flex-direction:column;width:100%;align-items:stretch}}