:root {
  color-scheme: light dark;
  --bg: #f4f5f7;
  --surface: #ffffff;
  --text: #15181e;
  --muted: #4f5765;
  --border: #d9dee8;
  --accent: #1f6feb;
}

html[data-theme="dark"] {
  --bg: #0e1117;
  --surface: #171b23;
  --text: #e9edf3;
  --muted: #b4bdc9;
  --border: #2b313d;
  --accent: #66a3ff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
  background: var(--bg);
  color: var(--text);
  font-family: "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
}

.container {
  width: min(100%, 900px);
}

.theme-toggle {
  margin-left: auto;
  margin-bottom: 16px;
  display: block;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  border-radius: 10px;
  padding: 10px 14px;
  font: inherit;
  cursor: pointer;
}

.theme-toggle:hover {
  border-color: var(--accent);
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: clamp(24px, 5vw, 48px);
  text-align: center;
}

h1 {
  margin: 0 0 12px;
  font-size: clamp(1.7rem, 3vw, 2.4rem);
  line-height: 1.2;
}

.message {
  margin: 0 auto 12px;
  max-width: 60ch;
  color: var(--muted);
}

a {
  color: var(--accent);
}

.back-soon {
  margin-top: 18px;
  font-weight: 600;
  letter-spacing: 0.02em;
}