:root {
  --radius: 20px;
}

* {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", "Noto Sans TC", sans-serif;
  background: radial-gradient(1200px 800px at 10% -10%, rgba(120,119,198,0.25), transparent),
              radial-gradient(1000px 600px at 90% 10%, rgba(236,72,153,0.18), transparent),
              radial-gradient(800px 600px at 50% 120%, rgba(14,165,233,0.18), transparent),
              #0b0b0c;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: -20%;
  background: conic-gradient(from 0deg at 50% 50%, rgba(167,139,250,0.08), rgba(236,72,153,0.08), rgba(56,189,248,0.08), rgba(167,139,250,0.08));
  filter: blur(80px);
  animation: spin 30s linear infinite;
  pointer-events: none;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

h1 {
  background: linear-gradient(90deg, #fff, #a1a1aa 40%, #c4b5fd);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

#form {
  backdrop-filter: blur(20px) saturate(160%);
  background: linear-gradient(180deg, rgba(24,24,27,0.75), rgba(24,24,27,0.55));
  border: 1px solid rgba(255,255,255,0.08);
  box-shadow: 0 30px 80px rgba(0,0,0,0.65), inset 0 1px 0 rgba(255,255,255,0.08);
  position: relative;
}

#form::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(180deg, rgba(255,255,255,0.12), rgba(255,255,255,0.02));
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
}

input, textarea {
  transition: border-color .15s ease, box-shadow .15s ease, background-color .15s ease;
  background: rgba(9,9,11,0.6);
}

input:focus, textarea:focus {
  border-color: #a78bfa;
  box-shadow: 0 0 0 3px rgba(167,139,250,0.25);
  background: rgba(9,9,11,0.8);
}

button {
  cursor: pointer;
  background: linear-gradient(180deg, #f4f4f5, #e4e4e7);
  transition: transform .08s ease, box-shadow .2s ease, background .2s ease;
  box-shadow: 0 8px 20px rgba(0,0,0,0.45), inset 0 1px 0 rgba(255,255,255,0.8);
}
button:hover {
  transform: translateY(-1px);
  box-shadow: 0 14px 30px rgba(0,0,0,0.55), inset 0 1px 0 rgba(255,255,255,0.9);
}
button:active {
  transform: translateY(0);
}

input[type="radio"] {
  accent-color: #a78bfa;
  width: 1rem;
  height: 1rem;
}