:root{--primary:#6c63ff;--primary-dark:#5a52d5;--secondary:#4facfe;--accent:#f093fb;--success:#27ae60;--warning:#f39c12;--danger:#e74c3c;--dark:#1a1a2e;--darker:#0f0f1a;--card-bg:rgba(255,255,255,0.05);--glass:rgba(255,255,255,0.08);--border:rgba(255,255,255,0.12);--text:#e2e8f0;--text-muted:#94a3b8;--sidebar-w:260px}
*{margin:0;padding:0;box-sizing:border-box}
body{font-family:"Inter",system-ui,sans-serif;background:var(--darker);color:var(--text);line-height:1.6;overflow-x:hidden}
body.light-mode{--darker:#f0f4f8;--dark:#ffffff;--card-bg:#ffffff;--glass:#f8fafc;--border:#e2e8f0;--text:#1e293b;--text-muted:#64748b}
a{color:var(--primary);text-decoration:none}
a:hover{color:var(--secondary)}
img{max-width:100%}
.container{max-width:1280px;margin:0 auto;padding:0 20px}
.glass-card{background:var(--glass);backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);border:1px solid var(--border);border-radius:16px;padding:24px;transition:transform .3s,box-shadow .3s}
.glass-card:hover{transform:translateY(-4px);box-shadow:0 20px 60px rgba(108,99,255,.2)}
.gradient-text{background:linear-gradient(135deg,var(--primary),var(--secondary));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.btn{display:inline-flex;align-items:center;gap:8px;padding:10px 24px;border-radius:10px;font-weight:600;font-size:14px;border:none;cursor:pointer;transition:all .3s;text-decoration:none}
.btn-primary{background:linear-gradient(135deg,var(--primary),var(--primary-dark));color:#fff;box-shadow:0 4px 20px rgba(108,99,255,.4)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 30px rgba(108,99,255,.5);color:#fff}
.btn-secondary{background:var(--glass);border:1px solid var(--border);color:var(--text)}
.btn-secondary:hover{background:var(--primary);color:#fff;border-color:var(--primary)}
.btn-success{background:linear-gradient(135deg,#27ae60,#2ecc71);color:#fff}
.btn-danger{background:linear-gradient(135deg,#e74c3c,#c0392b);color:#fff}
.btn-outline{background:transparent;border:2px solid var(--primary);color:var(--primary)}
.btn-outline:hover{background:var(--primary);color:#fff}
.btn-lg{padding:14px 36px;font-size:16px;border-radius:12px}
.btn-sm{padding:6px 16px;font-size:12px;border-radius:8px}
.navbar{position:fixed;top:0;left:0;right:0;z-index:1000;background:rgba(15,15,26,.9);backdrop-filter:blur(20px);border-bottom:1px solid var(--border);padding:0 24px;height:70px;display:flex;align-items:center;justify-content:space-between}
.navbar-brand{font-size:22px;font-weight:800;background:linear-gradient(135deg,var(--primary),var(--secondary));-webkit-background-clip:text;-webkit-text-fill-color:transparent}
.navbar-nav{display:flex;align-items:center;gap:8px;list-style:none}
.navbar-nav a{color:var(--text-muted);padding:8px 14px;border-radius:8px;font-size:14px;font-weight:500;transition:all .2s}
.navbar-nav a:hover,.navbar-nav a.active{color:var(--text);background:var(--glass)}
.navbar-actions{display:flex;align-items:center;gap:12px}
.sidebar{position:fixed;left:0;top:70px;bottom:0;width:var(--sidebar-w);background:rgba(15,15,26,.95);border-right:1px solid var(--border);overflow-y:auto;z-index:900;transition:transform .3s}
.sidebar::-webkit-scrollbar{width:4px}
.sidebar::-webkit-scrollbar-thumb{background:var(--primary);border-radius:4px}
.sidebar-header{padding:20px 20px 10px;font-size:11px;font-weight:700;color:var(--text-muted);text-transform:uppercase;letter-spacing:2px}
.sidebar-nav{list-style:none;padding:0 12px}
.sidebar-nav li a{display:flex;align-items:center;gap:12px;padding:11px 14px;border-radius:10px;color:var(--text-muted);font-size:14px;font-weight:500;transition:all .2s;margin-bottom:2px}
.sidebar-nav li a:hover,.sidebar-nav li a.active{background:linear-gradient(135deg,rgba(108,99,255,.2),rgba(79,172,254,.1));color:var(--text);border-left:3px solid var(--primary)}
.sidebar-nav li a i{width:20px;text-align:center;font-size:16px}
.sidebar-badge{margin-left:auto;background:var(--primary);color:#fff;font-size:10px;padding:2px 7px;border-radius:20px}
.main-content{margin-left:var(--sidebar-w);margin-top:70px;padding:30px;min-height:calc(100vh - 70px)}
.stats-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:20px;margin-bottom:30px}
.stat-card{background:var(--glass);border:1px solid var(--border);border-radius:16px;padding:24px;position:relative;overflow:hidden}
.stat-card .icon{width:48px;height:48px;border-radius:12px;display:flex;align-items:center;justify-content:center;font-size:22px;margin-bottom:16px}
.stat-card.blue .icon{background:rgba(108,99,255,.2);color:var(--primary)}
.stat-card.green .icon{background:rgba(39,174,96,.2);color:var(--success)}
.stat-card.orange .icon{background:rgba(243,156,18,.2);color:var(--warning)}
.stat-card.red .icon{background:rgba(231,76,60,.2);color:var(--danger)}
.stat-card .value{font-size:32px;font-weight:800;color:var(--text);line-height:1}
.stat-card .label{font-size:13px;color:var(--text-muted);margin-top:6px}
.stat-card .change{font-size:12px;margin-top:8px}
.stat-card .change.up{color:var(--success)}
.stat-card .change.down{color:var(--danger)}
.course-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:24px}
.course-card{background:var(--glass);border:1px solid var(--border);border-radius:16px;overflow:hidden;transition:all .3s;cursor:pointer}
.course-card:hover{transform:translateY(-6px);box-shadow:0 24px 60px rgba(108,99,255,.25);border-color:var(--primary)}
.course-card .thumbnail{position:relative;height:180px;overflow:hidden}
.course-card .thumbnail img{width:100%;height:100%;object-fit:cover;transition:transform .4s}
.course-card:hover .thumbnail img{transform:scale(1.05)}
.course-card .badge{position:absolute;top:12px;left:12px;background:var(--primary);color:#fff;font-size:11px;font-weight:700;padding:4px 10px;border-radius:20px}
.course-card .badge.free{background:var(--success)}
.course-card .badge.live{background:var(--danger);animation:pulse 2s infinite}
.course-card .body{padding:18px}
.course-card .category{font-size:11px;color:var(--primary);font-weight:600;text-transform:uppercase;letter-spacing:1px;margin-bottom:8px}
.course-card .title{font-size:16px;font-weight:700;color:var(--text);margin-bottom:8px;line-height:1.4;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.course-card .instructor{font-size:13px;color:var(--text-muted);margin-bottom:12px}
.course-card .meta{display:flex;align-items:center;gap:12px;font-size:12px;color:var(--text-muted);margin-bottom:14px}
.course-card .rating{color:#f39c12;font-weight:700}
.course-card .price .current{font-size:20px;font-weight:800;color:var(--primary)}
.course-card .price .original{font-size:14px;color:var(--text-muted);text-decoration:line-through}
.progress-bar{height:6px;background:rgba(255,255,255,.1);border-radius:10px;overflow:hidden}
.progress-fill{height:100%;background:linear-gradient(90deg,var(--primary),var(--secondary));border-radius:10px;transition:width .6s ease}
.hero{min-height:100vh;display:flex;align-items:center;background:radial-gradient(ellipse at 20% 50%,rgba(108,99,255,.15) 0%,transparent 60%),radial-gradient(ellipse at 80% 20%,rgba(79,172,254,.1) 0%,transparent 60%),var(--darker);position:relative;overflow:hidden;padding-top:70px}
.hero-title{font-size:clamp(36px,5vw,72px);font-weight:900;line-height:1.1;margin-bottom:24px}
.hero-subtitle{font-size:18px;color:var(--text-muted);margin-bottom:36px;max-width:560px}
.hero-stats{display:flex;gap:40px;margin-top:48px}
.hero-stat .number{font-size:32px;font-weight:800;color:var(--primary)}
.hero-stat .label{font-size:13px;color:var(--text-muted)}
.shape{position:absolute;border-radius:50%;filter:blur(80px);opacity:.15;pointer-events:none}
.shape-1{width:400px;height:400px;background:var(--primary);top:-100px;right:-100px}
.shape-2{width:300px;height:300px;background:var(--secondary);bottom:-50px;left:-50px}
.table-wrap{background:var(--glass);border:1px solid var(--border);border-radius:16px;overflow:hidden}
.data-table{width:100%;border-collapse:collapse}
.data-table th{background:rgba(108,99,255,.1);padding:14px 18px;text-align:left;font-size:12px;font-weight:700;color:var(--text-muted);text-transform:uppercase;letter-spacing:1px}
.data-table td{padding:14px 18px;border-bottom:1px solid var(--border);font-size:14px;color:var(--text)}
.data-table tr:last-child td{border-bottom:none}
.data-table tr:hover td{background:rgba(108,99,255,.05)}
.badge{display:inline-flex;align-items:center;padding:3px 10px;border-radius:20px;font-size:11px;font-weight:700;text-transform:uppercase;letter-spacing:.5px}
.badge-primary{background:rgba(108,99,255,.2);color:var(--primary)}
.badge-success{background:rgba(39,174,96,.2);color:var(--success)}
.badge-warning{background:rgba(243,156,18,.2);color:var(--warning)}
.badge-danger{background:rgba(231,76,60,.2);color:var(--danger)}
.badge-info{background:rgba(79,172,254,.2);color:var(--secondary)}
.form-group{margin-bottom:20px}
.form-label{display:block;font-size:13px;font-weight:600;color:var(--text-muted);margin-bottom:8px;text-transform:uppercase;letter-spacing:.5px}
.form-control{width:100%;background:var(--glass);border:1px solid var(--border);border-radius:10px;padding:12px 16px;color:var(--text);font-size:14px;transition:border-color .2s,box-shadow .2s;outline:none}
.form-control:focus{border-color:var(--primary);box-shadow:0 0 0 3px rgba(108,99,255,.15)}
.form-control::placeholder{color:var(--text-muted)}
select.form-control option{background:var(--dark);color:var(--text)}
textarea.form-control{resize:vertical;min-height:100px}
.alert{padding:14px 18px;border-radius:10px;font-size:14px;margin-bottom:20px;display:flex;align-items:center;gap:10px}
.alert-success{background:rgba(39,174,96,.15);border:1px solid rgba(39,174,96,.3);color:#2ecc71}
.alert-error{background:rgba(231,76,60,.15);border:1px solid rgba(231,76,60,.3);color:#e74c3c}
.alert-warning{background:rgba(243,156,18,.15);border:1px solid rgba(243,156,18,.3);color:#f39c12}
.alert-info{background:rgba(79,172,254,.15);border:1px solid rgba(79,172,254,.3);color:#4facfe}
.toast-container{position:fixed;top:90px;right:20px;z-index:9999;display:flex;flex-direction:column;gap:10px}
.toast{background:var(--dark);border:1px solid var(--border);border-radius:12px;padding:14px 18px;min-width:300px;display:flex;align-items:center;gap:12px;box-shadow:0 8px 32px rgba(0,0,0,.3);animation:slideIn .3s ease}
.toast.success{border-left:4px solid var(--success)}
.toast.error{border-left:4px solid var(--danger)}
.toast.info{border-left:4px solid var(--secondary)}
@keyframes slideIn{from{transform:translateX(100%);opacity:0}to{transform:translateX(0);opacity:1}}
@keyframes fadeIn{from{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.5}}
@keyframes spin{to{transform:rotate(360deg)}}
.fade-in{animation:fadeIn .5s ease forwards}
.skeleton{background:linear-gradient(90deg,var(--glass) 25%,rgba(255,255,255,.08) 50%,var(--glass) 75%);background-size:200% 100%;animation:shimmer 1.5s infinite;border-radius:8px}
@keyframes shimmer{0%{background-position:200% 0}100%{background-position:-200% 0}}
.player-layout{display:grid;grid-template-columns:1fr 340px;gap:0;height:calc(100vh - 70px);overflow:hidden}
.player-main{overflow-y:auto;padding:24px}
.player-sidebar{background:var(--dark);border-left:1px solid var(--border);overflow-y:auto}
.lesson-item{padding:12px 16px;border-bottom:1px solid var(--border);cursor:pointer;transition:background .2s;display:flex;align-items:center;gap:12px;font-size:13px}
.lesson-item:hover{background:var(--glass)}
.lesson-item.active{background:rgba(108,99,255,.15);border-left:3px solid var(--primary)}
.lesson-item.completed .check{color:var(--success)}
.lesson-content{background:var(--glass);border-radius:16px;padding:32px;min-height:400px}
.exam-container{max-width:900px;margin:0 auto}
.question-card{background:var(--glass);border:1px solid var(--border);border-radius:16px;padding:28px;margin-bottom:20px}
.question-number{font-size:12px;color:var(--primary);font-weight:700;text-transform:uppercase;margin-bottom:8px}
.question-text{font-size:16px;font-weight:600;margin-bottom:20px;line-height:1.6}
.option-label{display:flex;align-items:center;gap:12px;padding:12px 16px;border:1px solid var(--border);border-radius:10px;cursor:pointer;transition:all .2s;margin-bottom:10px}
.option-label:hover{border-color:var(--primary);background:rgba(108,99,255,.08)}
.option-label input[type=radio]{accent-color:var(--primary)}
.option-label.correct{border-color:var(--success);background:rgba(39,174,96,.1)}
.option-label.wrong{border-color:var(--danger);background:rgba(231,76,60,.1)}
.exam-timer{position:fixed;top:80px;right:20px;background:var(--dark);border:1px solid var(--border);border-radius:12px;padding:12px 20px;font-size:24px;font-weight:800;color:var(--primary);z-index:100}
.exam-timer.warning{color:var(--warning);animation:pulse 1s infinite}
.exam-timer.danger{color:var(--danger);animation:pulse .5s infinite}
.leaderboard-item{display:flex;align-items:center;gap:16px;padding:16px 20px;border-bottom:1px solid var(--border);transition:background .2s}
.leaderboard-item:hover{background:var(--glass)}
.rank-badge{width:36px;height:36px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-weight:800;font-size:14px;flex-shrink:0}
.rank-1{background:linear-gradient(135deg,#f6d365,#fda085);color:#fff}
.rank-2{background:linear-gradient(135deg,#c0c0c0,#a0a0a0);color:#fff}
.rank-3{background:linear-gradient(135deg,#cd7f32,#a0522d);color:#fff}
.rank-other{background:var(--glass);color:var(--text-muted)}
.avatar{border-radius:50%;object-fit:cover;flex-shrink:0}
.avatar-sm{width:32px;height:32px}
.avatar-md{width:48px;height:48px}
.avatar-lg{width:72px;height:72px}
.avatar-xl{width:100px;height:100px}
.notif-dot{position:relative}
.notif-dot::after{content:attr(data-count);position:absolute;top:-6px;right:-6px;background:var(--danger);color:#fff;font-size:10px;font-weight:700;min-width:18px;height:18px;border-radius:9px;display:flex;align-items:center;justify-content:center;padding:0 4px}
.modal-overlay{position:fixed;inset:0;background:rgba(0,0,0,.7);backdrop-filter:blur(4px);z-index:2000;display:flex;align-items:center;justify-content:center;opacity:0;pointer-events:none;transition:opacity .3s}
.modal-overlay.active{opacity:1;pointer-events:all}
.modal{background:var(--dark);border:1px solid var(--border);border-radius:20px;padding:32px;max-width:560px;width:90%;transform:scale(.9);transition:transform .3s}
.modal-overlay.active .modal{transform:scale(1)}
.tabs{display:flex;gap:4px;background:var(--glass);border-radius:12px;padding:4px;margin-bottom:24px}
.tab-btn{flex:1;padding:10px;border-radius:8px;border:none;background:transparent;color:var(--text-muted);font-size:14px;font-weight:600;cursor:pointer;transition:all .2s}
.tab-btn.active{background:var(--primary);color:#fff}
.accordion-item{border:1px solid var(--border);border-radius:12px;margin-bottom:8px;overflow:hidden}
.accordion-header{padding:16px 20px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;font-weight:600;background:var(--glass);transition:background .2s}
.accordion-header:hover{background:rgba(108,99,255,.1)}
.accordion-body{padding:0 20px;max-height:0;overflow:hidden;transition:max-height .3s ease,padding .3s}
.accordion-body.open{max-height:1000px;padding:16px 20px}
.sticky-buy{position:sticky;top:90px;background:var(--glass);border:1px solid var(--border);border-radius:20px;padding:24px;backdrop-filter:blur(20px)}
.stars{color:#f39c12;letter-spacing:2px}
.search-bar{display:flex;align-items:center;background:var(--glass);border:1px solid var(--border);border-radius:12px;padding:4px 4px 4px 16px;gap:8px}
.search-bar input{background:transparent;border:none;outline:none;color:var(--text);font-size:14px;flex:1}
.search-bar input::placeholder{color:var(--text-muted)}
.pagination{display:flex;gap:6px;justify-content:center;margin-top:32px}
.page-btn{width:38px;height:38px;border-radius:8px;border:1px solid var(--border);background:var(--glass);color:var(--text);font-size:14px;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all .2s}
.page-btn:hover,.page-btn.active{background:var(--primary);border-color:var(--primary);color:#fff}
.fab{position:fixed;bottom:30px;right:30px;width:56px;height:56px;border-radius:50%;background:linear-gradient(135deg,var(--primary),var(--secondary));color:#fff;font-size:24px;display:flex;align-items:center;justify-content:center;box-shadow:0 8px 32px rgba(108,99,255,.4);cursor:pointer;transition:transform .3s;z-index:500}
.fab:hover{transform:scale(1.1) rotate(90deg)}
.xp-bar{height:8px;background:rgba(255,255,255,.1);border-radius:10px;overflow:hidden;margin-top:6px}
.xp-fill{height:100%;background:linear-gradient(90deg,#f6d365,#fda085);border-radius:10px;transition:width .8s ease}
.cert-card{background:linear-gradient(135deg,#1a1a2e,#16213e);border:2px solid #c9a84c;border-radius:16px;padding:32px;text-align:center;position:relative;overflow:hidden}
.cert-card::before{content:"";position:absolute;inset:8px;border:1px solid rgba(201,168,76,.3);border-radius:10px;pointer-events:none}
::-webkit-scrollbar{width:6px;height:6px}
::-webkit-scrollbar-track{background:transparent}
::-webkit-scrollbar-thumb{background:rgba(108,99,255,.4);border-radius:3px}
::-webkit-scrollbar-thumb:hover{background:var(--primary)}
@media(max-width:1024px){.player-layout{grid-template-columns:1fr}.player-sidebar{display:none}}
@media(max-width:768px){.sidebar{transform:translateX(-100%)}.sidebar.open{transform:translateX(0)}.main-content{margin-left:0}.hero-stats{flex-wrap:wrap;gap:20px}.course-grid{grid-template-columns:1fr}.stats-grid{grid-template-columns:1fr 1fr}}
@media(max-width:480px){.stats-grid{grid-template-columns:1fr}.navbar-nav{display:none}}