:root {
  color-scheme: light dark;
  --bg: #f2f5f9;
  --surface: rgba(255, 255, 255, .92);
  --text: #152033;
  --muted: #617086;
  --line: #dce3ec;
  --accent: #2878e5;
  --accent-hover: #1768d1;
  --danger-bg: #fff0f0;
  --danger: #a82a2a;
  --shadow: 0 24px 80px rgba(28, 48, 78, .16);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f141d;
    --surface: rgba(25, 33, 45, .94);
    --text: #f3f6fa;
    --muted: #aab6c7;
    --line: #354154;
    --accent: #5598f4;
    --accent-hover: #76aafa;
    --danger-bg: #3a2024;
    --danger: #ffb1b1;
    --shadow: 0 24px 80px rgba(0, 0, 0, .35);
  }
}

* { box-sizing: border-box; }

body {
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(circle at 15% 15%, color-mix(in srgb, var(--accent) 16%, transparent), transparent 34rem),
    var(--bg);
  color: var(--text);
  font: 16px/1.5 Inter, "Segoe UI", system-ui, sans-serif;
}

.shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.card {
  width: min(100%, 440px);
  padding: 34px;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: var(--surface);
  box-shadow: var(--shadow);
  backdrop-filter: blur(16px);
}

.mark {
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  margin-bottom: 24px;
  border-radius: 15px;
  background: var(--accent);
  color: white;
  font-weight: 800;
}

.eyebrow {
  margin: 0 0 6px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .12em;
  text-transform: uppercase;
}

h1 {
  margin: 0 0 12px;
  font-size: clamp(28px, 6vw, 38px);
  line-height: 1.12;
  letter-spacing: -.035em;
}

.lead, .note, .status { color: var(--muted); }
.lead { margin: 0 0 24px; }
.note { margin: 22px 0 0; font-size: 13px; }
.status { margin: -10px 0 18px; font-size: 14px; }

label {
  display: block;
  margin: 0 0 7px;
  font-size: 14px;
  font-weight: 700;
}

input {
  width: 100%;
  min-height: 50px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  outline: none;
  background: transparent;
  color: var(--text);
  font: inherit;
}

input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 18%, transparent);
}

.code {
  text-align: center;
  font-size: 27px;
  font-weight: 750;
  letter-spacing: .35em;
}

button {
  width: 100%;
  min-height: 50px;
  margin-top: 14px;
  border: 0;
  border-radius: 12px;
  background: var(--accent);
  color: white;
  cursor: pointer;
  font: inherit;
  font-weight: 750;
}

button:hover { background: var(--accent-hover); }

.alert {
  margin: 0 0 18px;
  padding: 12px 14px;
  border-radius: 12px;
  background: var(--danger-bg);
  color: var(--danger);
  font-size: 14px;
}

.secondary {
  display: block;
  margin-top: 18px;
  color: var(--accent);
  text-align: center;
  text-decoration: none;
  font-size: 14px;
  font-weight: 700;
}