:root {
  --bg: #05070c;
  --carte: rgba(255, 255, 255, 0.035);
  --ligne: rgba(255, 255, 255, 0.1);
  --txt: #e4eef6;
  --txt-2: #97a7b8;
  --accent: #35e6ff;
  --rouge: #ff5d6c;
  --champ: rgba(0, 0, 0, 0.35);
}
@media (prefers-color-scheme: light) {
  :root {
    --bg: #f3f6fa;
    --carte: #ffffff;
    --ligne: rgba(15, 23, 36, 0.12);
    --txt: #0f1724;
    --txt-2: #556274;
    --accent: #0a8fb0;
    --rouge: #d23145;
    --champ: #f6f8fb;
  }
}

* { box-sizing: border-box; margin: 0; }

html, body { height: 100%; }
body {
  display: grid;
  place-items: center;
  padding: 16px;
  background:
    radial-gradient(700px 480px at 15% -10%, rgba(53, 230, 255, 0.09), transparent 60%),
    radial-gradient(600px 500px at 95% 110%, rgba(169, 123, 255, 0.08), transparent 60%),
    var(--bg);
  color: var(--txt);
  font-family: 'Inter', -apple-system, 'Segoe UI', Roboto, system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
}

.carte {
  width: 100%;
  max-width: 360px;
  padding: 34px 28px 26px;
  border: 1px solid var(--ligne);
  border-radius: 16px;
  background: var(--carte);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.35);
  text-align: center;
}

.noyau {
  width: 34px; height: 34px; margin: 0 auto 18px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent) 0 28%, transparent 30%);
  box-shadow: 0 0 0 1px var(--accent), 0 0 26px rgba(53, 230, 255, 0.45);
  animation: pouls 3.2s ease-in-out infinite;
}
@keyframes pouls { 50% { box-shadow: 0 0 0 1px var(--accent), 0 0 42px rgba(53, 230, 255, 0.7); } }
@media (prefers-reduced-motion: reduce) { .noyau { animation: none; } }

h1 { font-size: 26px; letter-spacing: 0.32em; font-weight: 700; padding-left: 0.32em; }
.sous { margin-top: 6px; font-size: 10.5px; letter-spacing: 0.22em; color: var(--txt-2); }

form { margin-top: 28px; display: grid; gap: 10px; text-align: left; }
label { font-size: 12px; color: var(--txt-2); }
input {
  width: 100%;
  padding: 11px 13px;
  border: 1px solid var(--ligne);
  border-radius: 10px;
  background: var(--champ);
  color: var(--txt);
  font: inherit;
  font-size: 15px;
  outline: none;
}
input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(53, 230, 255, 0.15); }
button {
  margin-top: 6px;
  padding: 11px;
  border: 0;
  border-radius: 10px;
  background: var(--accent);
  color: #04131a;
  font: inherit;
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
}
button:disabled { opacity: 0.6; cursor: default; }
.err { min-height: 18px; font-size: 12.5px; color: var(--rouge); }
.pied { margin-top: 18px; font-size: 11px; line-height: 1.5; color: var(--txt-2); }

/* Apres les regles de base, pour l'emporter sur elles. */
@media (prefers-color-scheme: light) {
  .carte { box-shadow: 0 18px 50px rgba(15, 23, 36, 0.1); }
  button { color: #fff; }
}