:root {
  --bg: #0d0d0d;
  --card-bg: rgba(255, 255, 255, 0.05);
  --primary: #00f5ff;
  --accent: #ff00c8;
  --radius: 16px;
  --glass-border: rgba(255, 255, 255, 0.1);
}
*{margin:0;padding:0;box-sizing:border-box}
body{
  height:100vh;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(-45deg,var(--bg),#1a1a2e,#16213e,#0f3460);
  background-size:400% 400%;animation:gradientShift 8s ease infinite;
  font-family:"Poppins",sans-serif;color:#fff;overflow:hidden;
}
@keyframes gradientShift{0%{background-position:0% 50%}50%{background-position:100% 50%}100%{background-position:0% 50%}}
#particles-js{position:absolute;width:100%;height:100%;z-index:0}
.theme-toggle{position:absolute;top:20px;right:20px;background:rgba(255,255,255,.1);border:none;padding:10px;border-radius:50%;cursor:pointer;transition:.3s;font-size:18px}
.theme-toggle:hover{background:rgba(255,255,255,.2)}
.card{position:relative;z-index:1;width:360px;padding:40px 30px;background:var(--card-bg);backdrop-filter:blur(10px);border:1px solid var(--glass-border);border-radius:var(--radius);box-shadow:0 8px 32px rgba(0,0,0,.37);text-align:center}
.logo{font-size:28px;font-weight:600;margin-bottom:8px;background:linear-gradient(90deg,var(--primary),var(--accent));-webkit-background-clip:text;-webkit-text-fill-color:transparent;animation:glitch 3s infinite}
@keyframes glitch{0%,100%{text-shadow:0 0 5px var(--primary),0 0 10px var(--accent)}20%{text-shadow:2px 0 5px var(--primary),-2px 0 5px var(--accent)}}
.sub{font-size:14px;color:#bbb;margin-bottom:30px}
.field{position:relative;margin-bottom:24px;text-align:left}
.field label{font-size:13px;color:#ccc;margin-left:8px}
.field input{width:100%;padding:12px 16px;margin-top:4px;border:none;border-radius:8px;background:rgba(255,255,255,.08);color:#fff;font-size:15px;transition:.3s}
.field input:focus{outline:none;background:rgba(255,255,255,.12);box-shadow:0 0 0 2px var(--primary)}
.btn{width:100%;padding:14px;margin-top:10px;border:none;border-radius:8px;background:linear-gradient(90deg,var(--primary),var(--accent));color:#000;font-weight:600;cursor:pointer;transition:transform .2s,box-shadow .3s}
.btn:hover{transform:translateY(-2px);box-shadow:0 0 15px var(--primary)}
.footer{margin-top:20px;font-size:13px}
.footer a{color:var(--primary);text-decoration:none}
.footer a:hover{text-decoration:underline}