/* ============================================
   CSS CUSTOM PROPERTIES
   ============================================ */
:root {
  --surface: #efefef;
  --bg: #f8f8f8;
  --bg-secondary: #efefef;
  --text: #111111;
  --text-muted: #666666;
  --accent: #3b5bdb;
  --accent-hover: #2f4ac7;
  --border: #e0e0e0;
  --card-bg: #ffffff;

  --font-sans: 'DM Sans', system-ui, sans-serif;
  --font-mono: 'DM Mono', 'Fira Code', monospace;

  --radius: 6px;
  --max-width: 760px;
  --transition: 150ms ease;
}

[data-theme="dark"] {
  --surface: #2a2a40;
  --bg: #1a1a2e;
  --bg-secondary: #22223b;
  --text: #f0f0f0;
  --text-muted: #9999bb;
  --accent: #6b8cff;
  --accent-hover: #839dff;
  --border: #2e2e4a;
  --card-bg: #22223b;
}

/* ============================================
   RESET
   ============================================ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  line-height: 1.6;
  transition: background-color var(--transition), color var(--transition);
  min-height: 100vh;
}

img, video {
  max-width: 100%;
  display: block;
}

a {
  color: var(--accent);
  text-decoration: none;
}

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

code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--bg-secondary);
  padding: 0.15em 0.4em;
  border-radius: 3px;
}

/* ============================================
   LAYOUT
   ============================================ */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ============================================
   TYPOGRAPHY
   ============================================ */
h1, h2, h3, h4 {
  line-height: 1.2;
  font-weight: 600;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2rem, 5vw, 3rem); }
h2 { font-size: clamp(1.4rem, 3vw, 1.75rem); }
h3 { font-size: 1.25rem; }

p {
  color: var(--text);
}

.text-muted {
  color: var(--text-muted);
}


/* ============================================
   BUTTONS
   ============================================ */
.btn-primary {
  background: var(--accent);
  color: #fff !important;
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius);
  font-weight: 500;
  font-size: 0.9rem;
  transition: background var(--transition);
  display: inline-block;
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff !important;
}

.btn-secondary {
  color: var(--text-muted) !important;
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  font-weight: 500;
  font-size: 0.9rem;
  transition: color var(--transition), border-color var(--transition);
  display: inline-block;
}

.btn-secondary:hover {
  color: var(--text) !important;
  border-color: var(--text-muted);
}