:root {
  color-scheme: dark light;
  --bg: #0E0D0B;
  --surface: #151412;
  --line-strong: #3A3631;
  --text: #F2EDE4;
  --muted: #B4ACA0;
  --accent: #F2A33A;
  --accent-hover: #F7B456;
  --on-accent: #1F1404;
  --error: #F08C7A;
  --mark-a: #F2A33A;
  --mark-b: #F6E7C8;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #F2EDE4;
    --surface: #FBF8F3;
    --line-strong: #CFC5B5;
    --text: #1B1A17;
    --muted: #4F4940;
    --error: #A3341F;
    --mark-b: #1B1A17;
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  display: grid;
  min-height: 100vh;
  margin: 0;
  padding: 24px 16px;
  place-items: center;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.7 system-ui, "Segoe UI", Tahoma, sans-serif;
}

.gate {
  width: 100%;
  max-width: 380px;
  text-align: center;
}

.mark {
  width: 64px;
  height: 64px;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 14;
}

.mark-a {
  stroke: var(--mark-a);
}

.mark-b {
  stroke: var(--mark-b);
}

h1 {
  margin: 16px 0 8px;
  font-size: 30px;
  line-height: 1.3;
}

p {
  margin: 0 0 24px;
  color: var(--muted);
}

form {
  display: grid;
  gap: 10px;
  text-align: start;
}

label {
  font-size: 15px;
  font-weight: 600;
}

input {
  min-height: 52px;
  padding: 0 16px;
  border: 1px solid var(--line-strong);
  border-radius: 12px;
  background: var(--surface);
  color: var(--text);
  font: 600 18px/1 ui-monospace, Menlo, Consolas, monospace;
  letter-spacing: 0.08em;
  text-align: center;
}

input:focus-visible,
button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.error {
  margin: 0;
  color: var(--error);
  font-size: 15px;
}

button {
  min-height: 52px;
  border: 0;
  border-radius: 12px;
  background: var(--accent);
  color: var(--on-accent);
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}

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