:root{
  --bg:#121212;
  --text:#fff;
  --accent:#ff00c1;
  --grad:linear-gradient(90deg,#ff00c1,#9600ff,#4900ff,#00b8ff,#00ff85);
}
body{margin:0;font-family:-apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;background:var(--bg);color:var(--text);display:flex;align-items:center;justify-content:center;height:100vh;text-align:center;}
h1{font-size:2.5rem;margin-bottom:.5rem;}
.rainbow{background:var(--grad);-webkit-background-clip:text;-webkit-text-fill-color:transparent;}
p{font-size:1.2rem;opacity:.8;margin-bottom:2rem;}
button{font-size:1.1rem;padding:14px 40px;border:none;border-radius:30px;background:var(--grad);color:#fff;cursor:pointer;transition:.3s;}
button:hover{transform:translateY(-2px);box-shadow:0 0 20px var(--accent);}