body{margin:0;font-family:'Poppins',sans-serif;transition:0.4s;}
body.dark{background:#1e1e2f;color:white;}
body.light{background:#f4f4f4;color:#111;}
.hero{position:relative;width:100%;height:400px;overflow:hidden;}
.hero-video{width:100%;height:100%;object-fit:cover;position:absolute;top:0;left:0;z-index:-1;}
.hero-overlay{position:absolute;top:0;left:0;width:100%;height:100%;display:flex;flex-direction:column;justify-content:center;align-items:center;color:white;text-align:center;}
.logo{font-size:3rem;font-weight:700;animation:fadeIn 2s ease-in-out;}
@keyframes fadeIn{0%{opacity:0;transform:translateY(-20px);}100%{opacity:1;transform:translateY(0);}}
.side-nav{position:fixed;left:0;top:0;width:200px;height:100%;background:rgba(0,0,0,.7);color:white;padding:20px;}
.side-nav h3{margin-bottom:10px;}
.side-nav ul{list-style:none;padding:0;}
.side-nav li{margin:10px 0;}
.side-nav a{color:white;text-decoration:none;}
.side-nav a:hover{color:#00d4ff;}
.container{margin-left:220px;padding:20px;}
.videoGrid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:20px;}
.videoGrid iframe{width:100%;height:200px;border-radius:10px;}
.card{background:rgba(255,255,255,.1);padding:15px;margin-bottom:20px;border-radius:12px;}
.top-nav{display:flex;align-items:center;gap:15px;padding:10px;background:rgba(0,0,0,.7);position:sticky;top:0;z-index:100;}
.top-nav a{color:white;text-decoration:none;}
.top-nav input{margin-left:auto;padding:5px;border-radius:5px;border:none;}
button{cursor:pointer;padding:8px 12px;border:none;border-radius:5px;background:#00d4ff;color:white;}