:root{--bg: #0a0a0a;--bg2: #111111;--bg3: #1a1a1a;--accent: #ff6b00;--accent2: #ffaa00;--text: #f0f0f0;--text2: #999;--border: #2a2a2a;--physics: #ff6b00;--chemistry: #00c9a7;--maths: #7c3aed}*{margin:0;padding:0;box-sizing:border-box}body{background:var(--bg);color:var(--text);font-family:Rajdhani,sans-serif;font-size:16px;min-height:100vh}a{text-decoration:none;color:inherit}.navbar{display:flex;align-items:center;justify-content:space-between;padding:0 2rem;height:64px;background:var(--bg2);border-bottom:2px solid var(--accent);position:sticky;top:0;z-index:100}.navbar-brand{font-family:Bebas Neue,sans-serif;font-size:1.8rem;letter-spacing:3px;color:var(--accent);text-shadow:0 0 20px rgba(255,107,0,.4)}.navbar-brand span{color:var(--text)}.navbar-links{display:flex;gap:1rem;align-items:center}.nav-btn{background:transparent;border:1px solid var(--border);color:var(--text2);padding:.4rem 1rem;font-family:Rajdhani,sans-serif;font-size:.9rem;font-weight:600;letter-spacing:1px;cursor:pointer;transition:all .2s;text-transform:uppercase}.nav-btn:hover,.nav-btn.active{border-color:var(--accent);color:var(--accent)}.hero{padding:5rem 2rem 4rem;text-align:center;position:relative;overflow:hidden}.hero:before{content:"";position:absolute;top:-50%;left:50%;transform:translate(-50%);width:600px;height:600px;background:radial-gradient(circle,rgba(255,107,0,.08) 0%,transparent 70%);pointer-events:none}.hero-tag{display:inline-block;background:var(--accent);color:#000;font-family:Space Mono,monospace;font-size:.7rem;font-weight:700;letter-spacing:3px;padding:.3rem 1rem;margin-bottom:1.5rem;text-transform:uppercase}.hero h1{font-family:Bebas Neue,sans-serif;font-size:clamp(3rem,10vw,7rem);letter-spacing:6px;line-height:1;color:var(--text);margin-bottom:.5rem}.hero h1 .highlight{color:var(--accent);display:block}.hero p{color:var(--text2);font-size:1.1rem;font-weight:500;letter-spacing:2px;margin-top:1rem;text-transform:uppercase}.subjects-section{padding:2rem;max-width:1100px;margin:0 auto}.section-title{font-family:Space Mono,monospace;font-size:.75rem;letter-spacing:4px;color:var(--text2);text-transform:uppercase;margin-bottom:2rem;display:flex;align-items:center;gap:1rem}.section-title:after{content:"";flex:1;height:1px;background:var(--border)}.subjects-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:1.5rem}.subject-card{background:var(--bg2);border:1px solid var(--border);padding:2.5rem 2rem;cursor:pointer;transition:all .3s;position:relative;overflow:hidden}.subject-card:before{content:"";position:absolute;bottom:0;left:0;right:0;height:3px;background:var(--card-color);transform:scaleX(0);transition:transform .3s}.subject-card:hover:before{transform:scaleX(1)}.subject-card:hover{border-color:var(--card-color);transform:translateY(-4px);box-shadow:0 20px 40px #0006}.subject-icon{font-size:3rem;margin-bottom:1rem;display:block}.subject-card h2{font-family:Bebas Neue,sans-serif;font-size:2.2rem;letter-spacing:4px;color:var(--card-color);margin-bottom:.5rem}.subject-card p{color:var(--text2);font-size:.95rem;font-weight:500;letter-spacing:1px}.subject-card .arrow{position:absolute;right:1.5rem;bottom:1.5rem;color:var(--card-color);font-size:1.5rem;opacity:0;transition:opacity .3s,transform .3s}.subject-card:hover .arrow{opacity:1;transform:translate(4px)}.page-container{max-width:900px;margin:0 auto;padding:2rem}.back-btn{display:inline-flex;align-items:center;gap:.5rem;color:var(--text2);font-size:.9rem;font-weight:600;letter-spacing:2px;text-transform:uppercase;margin-bottom:2rem;cursor:pointer;transition:color .2s;background:none;border:none}.back-btn:hover{color:var(--accent)}.page-header{margin-bottom:3rem;padding-bottom:2rem;border-bottom:1px solid var(--border)}.page-header .subject-label{font-family:Space Mono,monospace;font-size:.7rem;letter-spacing:4px;text-transform:uppercase;padding:.3rem .8rem;margin-bottom:1rem;display:inline-block}.page-header h1{font-family:Bebas Neue,sans-serif;font-size:clamp(2.5rem,6vw,4rem);letter-spacing:5px}.chapters-list{display:flex;flex-direction:column;gap:.75rem}.chapter-item{display:flex;align-items:center;gap:1.5rem;padding:1.2rem 1.5rem;background:var(--bg2);border:1px solid var(--border);cursor:pointer;transition:all .2s}.chapter-item:hover{border-color:var(--card-color);background:var(--bg3);padding-left:2rem}.chapter-num{font-family:Space Mono,monospace;font-size:.75rem;color:var(--text2);min-width:30px}.chapter-title{flex:1;font-size:1.05rem;font-weight:600;letter-spacing:1px}.chapter-play{color:var(--card-color);font-size:1.2rem;opacity:.5;transition:opacity .2s}.chapter-item:hover .chapter-play{opacity:1}.video-container{background:#000;aspect-ratio:16/9;width:100%;margin-bottom:2rem;border:1px solid var(--border);overflow:hidden}.video-container iframe{width:100%;height:100%;border:none;display:block}.video-info{background:var(--bg2);border:1px solid var(--border);padding:1.5rem;margin-bottom:1rem}.video-info h2{font-family:Bebas Neue,sans-serif;font-size:1.8rem;letter-spacing:3px;margin-bottom:.5rem}.video-info .meta{font-family:Space Mono,monospace;font-size:.7rem;letter-spacing:2px;color:var(--text2);text-transform:uppercase}.admin-page{max-width:800px;margin:0 auto;padding:2rem}.admin-login{max-width:400px;margin:5rem auto;padding:2rem;background:var(--bg2);border:1px solid var(--border)}.admin-login h2{font-family:Bebas Neue,sans-serif;font-size:2rem;letter-spacing:4px;margin-bottom:2rem;color:var(--accent)}.form-group{margin-bottom:1.2rem}.form-group label{display:block;font-family:Space Mono,monospace;font-size:.7rem;letter-spacing:3px;color:var(--text2);text-transform:uppercase;margin-bottom:.5rem}.form-group input,.form-group select,.form-group textarea{width:100%;background:var(--bg3);border:1px solid var(--border);color:var(--text);padding:.75rem 1rem;font-family:Rajdhani,sans-serif;font-size:1rem;outline:none;transition:border-color .2s}.form-group input:focus,.form-group select:focus,.form-group textarea:focus{border-color:var(--accent)}.form-group select option{background:var(--bg3)}.btn-primary{background:var(--accent);color:#000;border:none;padding:.75rem 2rem;font-family:Rajdhani,sans-serif;font-size:1rem;font-weight:700;letter-spacing:2px;text-transform:uppercase;cursor:pointer;width:100%;transition:background .2s}.btn-primary:hover{background:var(--accent2)}.btn-danger{background:transparent;color:#f44;border:1px solid #ff4444;padding:.4rem .8rem;font-family:Rajdhani,sans-serif;font-size:.85rem;font-weight:600;letter-spacing:1px;cursor:pointer;transition:all .2s}.btn-danger:hover{background:#f44;color:#fff}.admin-section{background:var(--bg2);border:1px solid var(--border);padding:1.5rem;margin-bottom:1.5rem}.admin-section h3{font-family:Bebas Neue,sans-serif;font-size:1.4rem;letter-spacing:3px;margin-bottom:1.2rem;color:var(--accent);padding-bottom:.75rem;border-bottom:1px solid var(--border)}.admin-list-item{display:flex;align-items:center;justify-content:space-between;padding:.75rem 0;border-bottom:1px solid var(--border);gap:1rem}.admin-list-item:last-child{border-bottom:none}.admin-list-item span{font-weight:600;flex:1}.error-msg{color:#f44;font-size:.85rem;margin-top:.5rem;font-family:Space Mono,monospace}.success-msg{color:#00c9a7;font-size:.85rem;margin-top:.5rem;font-family:Space Mono,monospace}.loading{text-align:center;padding:4rem;color:var(--text2);font-family:Space Mono,monospace;font-size:.85rem;letter-spacing:3px}.empty-state{text-align:center;padding:3rem;color:var(--text2);border:1px dashed var(--border)}.empty-state p{font-size:.95rem;margin-bottom:.5rem}.empty-state small{font-family:Space Mono,monospace;font-size:.7rem;letter-spacing:2px}@media (max-width: 768px){.navbar{padding:0 1rem;height:56px}.navbar-brand{font-size:1.2rem;letter-spacing:1px}.nav-btn{padding:.3rem .6rem;font-size:.8rem}.hero{padding:3rem 1.2rem 2.5rem}.hero h1{font-size:clamp(2.5rem,15vw,4rem);letter-spacing:3px}.hero p{font-size:.85rem;letter-spacing:1px}.subjects-section{padding:1.2rem}.subjects-grid{grid-template-columns:1fr;gap:1rem}.subject-card{padding:1.8rem 1.5rem}.subject-card h2{font-size:1.8rem}.page-container{padding:1.2rem}.page-header h1{font-size:clamp(2rem,10vw,3rem);letter-spacing:3px}.chapter-item{padding:1rem}.chapter-item:hover{padding-left:1.2rem}.video-container{aspect-ratio:16/9}.admin-page{padding:1.2rem}.admin-login{margin:2rem auto;padding:1.5rem}.admin-list-item{flex-wrap:wrap;gap:.5rem}.admin-list-item span{width:100%}}.footer{text-align:center;padding:2rem;border-top:1px solid var(--border);margin-top:4rem;color:var(--text2);font-family:Space Mono,monospace;font-size:.7rem;letter-spacing:2px}.footer span{color:var(--accent)}