:root {
  color-scheme: light;
  --bg: #f7f7f2;
  --surface: #ffffff;
  --text: #1f2933;
  --muted: #667085;
  --border: #d9ded6;
  --accent: #0f8b8d;
  --accent-strong: #0b6f71;
  --shadow: 0 18px 50px rgba(31, 41, 51, 0.12);
}

body.dark {
  color-scheme: dark;
  --bg: #111827;
  --surface: #1f2937;
  --text: #f8fafc;
  --muted: #cbd5e1;
  --border: #334155;
  --accent: #38bdf8;
  --accent-strong: #7dd3fc;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
}

* {
  box-sizing: border-box;
}

body {
  min-height: 100vh;
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Arial, Helvetica, sans-serif;
  transition: background 180ms ease, color 180ms ease;
}

.app-shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 32px;
}

.hero {
  width: min(100%, 920px);
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 28px;
  align-items: center;
}

.hero-copy,
.theme-panel {
  border: 1px solid var(--border);
  background: var(--surface);
  box-shadow: var(--shadow);
  border-radius: 8px;
}

.hero-copy {
  padding: 42px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: clamp(2.2rem, 6vw, 4.5rem);
  line-height: 0.98;
  letter-spacing: 0;
}

.description {
  max-width: 560px;
  margin: 22px 0 0;
  color: var(--muted);
  font-size: 1.05rem;
  line-height: 1.6;
}

.theme-panel {
  display: grid;
  gap: 18px;
  padding: 24px;
}

.theme-status {
  min-height: 44px;
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--muted);
  font-weight: 700;
}

.status-dot {
  width: 14px;
  height: 14px;
  border-radius: 999px;
  background: var(--accent);
  box-shadow: 0 0 0 5px color-mix(in srgb, var(--accent), transparent 78%);
}

.theme-toggle {
  min-height: 56px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  border: 0;
  border-radius: 8px;
  background: var(--accent);
  color: #ffffff;
  cursor: pointer;
  font: inherit;
  font-weight: 800;
  transition: background 180ms ease, transform 180ms ease;
}

.theme-toggle:hover {
  background: var(--accent-strong);
  transform: translateY(-1px);
}

.theme-toggle:focus-visible {
  outline: 3px solid var(--accent-strong);
  outline-offset: 3px;
}

.toggle-icon {
  width: 22px;
  display: inline-flex;
  justify-content: center;
  font-size: 1.2rem;
}

@media (max-width: 720px) {
  .app-shell {
    padding: 20px;
  }

  .hero {
    grid-template-columns: 1fr;
  }

  .hero-copy {
    padding: 30px;
  }

  .theme-panel {
    padding: 20px;
  }
}