/* Global base styles and responsive helpers */
:root {
  --primary: #6200ee;
  --secondary: #03dac6;
  --bg: #121212;
  --surface: #1e1e1e;
  --text: #e0e0e0;
  --text-strong: #ffffff;
  --border: #2a2a2a;
}

body {
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 16px;
}

.card {
  background: var(--surface);
  border-radius: 12px;
  box-shadow: 0 8px 16px rgba(0,0,0,0.2);
  border: 1px solid var(--border);
}

.btn {
  display: inline-block;
  padding: 10px 16px;
  border-radius: 999px;
  border: 2px solid var(--primary);
  color: var(--text-strong);
  text-decoration: none;
  background: transparent;
}

.grid {
  display: grid;
  gap: 16px;
}

/* Responsive helpers */
.grid.cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid.cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid.cols-1 { grid-template-columns: 1fr; }

@media (max-width: 900px) {
  .container { padding: 12px; }
  .grid.cols-3 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 600px) {
  .container { padding: 10px; }
  .grid.cols-2, .grid.cols-3 { grid-template-columns: 1fr; }
}

/* Light theme override (toggle via body.light-theme) */
body.light-theme {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --text: #1f2937;
  --text-strong: #111827;
  --border: #e5e7eb;
}

/* Utility spacing */
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 12px; }
.mt-3 { margin-top: 16px; }
.mt-4 { margin-top: 24px; }
.center { text-align: center; }