:root[data-theme="dark"] {
  --bg-1: #0f172a; --bg-2: #1e293b; --bg-3: #334155;
  --card-bg: rgba(255, 255, 255, 0.05);
  --card-border: rgba(255, 255, 255, 0.1);
  --text: #f1f5f9; --text-dim: #94a3b8; --text-mute: #cbd5e1;
  --accent: #38bdf8; --accent-bg: rgba(56, 189, 248, 0.15); --accent-text: #7dd3fc;
  --shadow: 0 8px 32px rgba(0,0,0,0.3);
}
:root[data-theme="light"] {
  --bg-1: #f1f5f9; --bg-2: #e2e8f0; --bg-3: #cbd5e1;
  --card-bg: rgba(255, 255, 255, 0.85);
  --card-border: rgba(15, 23, 42, 0.1);
  --text: #0f172a; --text-dim: #475569; --text-mute: #334155;
  --accent: #0284c7; --accent-bg: rgba(2, 132, 199, 0.12); --accent-text: #0369a1;
  --shadow: 0 8px 32px rgba(15, 23, 42, 0.1);
}
* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: linear-gradient(135deg, var(--bg-1) 0%, var(--bg-2) 50%, var(--bg-3) 100%);
  color: var(--text);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  transition: background 0.3s, color 0.3s;
}
.container { max-width: 1200px; width: 100%; }
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 32px;
}
h1 { font-weight: 300; font-size: 28px; letter-spacing: 1px; margin: 0; }
.subtitle { color: var(--text-dim); font-size: 14px; margin: 4px 0 0; }
.toolbar { display: flex; gap: 8px; }
.btn {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  color: var(--text);
  padding: 8px 14px;
  border-radius: 10px;
  cursor: pointer;
  font-size: 13px;
  font-weight: 500;
  backdrop-filter: blur(10px);
  transition: all 0.2s;
}
.btn:hover { background: var(--accent-bg); border-color: var(--accent); }
.btn.active { background: var(--accent-bg); color: var(--accent-text); border-color: var(--accent); }
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}
.card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 16px;
  padding: 20px;
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow);
  transition: transform 0.2s, background 0.3s, border-color 0.3s;
}
.card:hover { transform: translateY(-2px); }
.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}
.city { font-size: 15px; font-weight: 500; }
.flag { font-size: 26px; }
.time {
  font-size: 40px;
  font-weight: 200;
  letter-spacing: 1px;
  font-variant-numeric: tabular-nums;
  margin: 8px 0 4px;
  color: var(--accent);
}
.date { font-size: 13px; color: var(--text-mute); }
.meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 12px;
}
.offset {
  padding: 3px 8px;
  background: var(--accent-bg);
  color: var(--accent-text);
  border-radius: 10px;
  font-size: 11px;
  font-weight: 500;
}
.day {
  font-size: 11px;
  color: var(--text-dim);
}
.day .next { color: #fbbf24; }
.footer {
  text-align: center;
  margin-top: 32px;
  color: var(--text-dim);
  font-size: 12px;
}