/* ============================================
   Atoms — smallest UI building blocks
   ============================================ */

/* --- Typography --- */
body {
  font-family: var(--font-sans);
  color: var(--text-1);
  background: var(--surface-1);
  line-height: var(--leading-relaxed);
  letter-spacing: -0.01em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  font-feature-settings: "kern" 1, "liga" 1, "calt" 1;
}

h1, h2, h3, h4 {
  font-family: var(--font-serif);
  color: var(--text-1);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: var(--leading-tight);
  text-wrap: balance;
}

h1 { font-size: var(--type-h1); }
h2 { font-size: var(--type-h2); }
h3 { font-size: var(--type-h3); }

p {
  color: var(--text-2);
  margin-bottom: 1.5rem;
}

a {
  color: var(--text-1);
  text-decoration: none;
  transition: color var(--transition-quick);
}

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

small, .text-small {
  font-size: var(--type-xs);
  color: var(--text-3);
}

/* --- Labels --- */
.label {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--type-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--text-3);
}

.label--accent {
  color: var(--brand-warm);
}

/* --- Button --- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--size-2);
  padding: 0.75rem 2rem;
  font-family: var(--font-sans);
  font-size: var(--type-small);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  cursor: pointer;
  border: none;
  transition: all var(--transition-normal);
  text-decoration: none;
}

.btn:hover { text-decoration: none; }

.btn-primary {
  background: var(--text-1);
  color: var(--surface-1);
}

.btn-primary:hover {
  background: var(--text-1);
  color: var(--surface-1);
  opacity: 0.85;
}

.btn-ghost {
  background: transparent;
  color: var(--text-2);
  padding: var(--size-1) var(--size-2);
  text-transform: none;
  letter-spacing: normal;
}

.btn-ghost:hover {
  color: var(--text-1);
}

.btn-brand {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  padding: var(--btn-padding-y) var(--btn-padding-x);
  font-size: var(--btn-font-size);
  background: var(--brand-warm);
  color: #ffffff;
  border: none;
  border-radius: var(--btn-radius);
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-sm);
}
.btn-brand:hover {
  background: var(--brand-warm-dark);
  color: #ffffff;
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}
.btn-brand:focus-visible {
  outline: 2px solid var(--brand-warm);
  outline-offset: 2px;
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  padding: var(--btn-padding-y) var(--btn-padding-x);
  font-size: var(--btn-font-size);
  background: transparent;
  color: var(--text-1);
  border: 1px solid var(--border-color);
  border-radius: var(--btn-radius);
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition-normal);
}
.btn-outline:hover {
  background: var(--surface-2);
  color: var(--text-1);
  border-color: var(--brand-warm);
}
.btn-outline:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* --- Badge / Tag --- */
.badge {
  display: inline-block;
  padding: var(--size-1) var(--size-2);
  font-family: var(--font-mono);
  font-size: var(--type-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: -0.02em;
  background: var(--surface-2);
  color: var(--text-1);
}

/* --- Code --- */
code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: var(--surface-2);
  padding: 0.125rem 0.375rem;
  border-radius: var(--radius-sm);
}

pre {
  background: var(--surface-2);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: var(--size-4);
  overflow-x: auto;
  position: relative;
  margin-bottom: var(--size-5);
}

pre code {
  background: none;
  padding: 0;
  font-size: 0.9em;
}

/* --- Code Copy Button --- */
.code-copy-btn {
  position: absolute;
  top: var(--size-2);
  right: var(--size-2);
  background: var(--surface-3);
  border: none;
  border-radius: 3px;
  padding: var(--size-1) var(--size-2);
  font-size: var(--type-xs);
  color: var(--text-3);
  cursor: pointer;
  opacity: 0;
  transition: opacity var(--transition-quick);
}

pre:hover .code-copy-btn { opacity: 1; }
.code-copy-btn:hover { color: var(--text-1); }

/* --- Theme Toggle --- */
.theme-toggle {
  background: none;
  border: none;
  padding: var(--size-1);
  border-radius: 4px;
  cursor: pointer;
  color: var(--text-3);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  transition: color var(--transition-quick);
}

.theme-toggle:hover {
  color: var(--text-1);
}

.theme-toggle svg {
  width: 1.25rem;
  height: 1.25rem;
}

/* --- CTA Link (animated underline) --- */
.cta-link {
  position: relative;
  display: inline-block;
  font-weight: 500;
  color: var(--text-1);
  text-decoration: none;
}

.cta-link::after {
  content: '';
  position: absolute;
  width: 100%;
  height: 2px;
  bottom: -2px;
  left: 0;
  background-color: var(--brand-warm);
  transform: scaleX(0);
  transform-origin: bottom right;
  transition: transform var(--transition-spring);
}

.cta-link:hover::after {
  transform: scaleX(1);
  transform-origin: bottom left;
}

/* --- Divider --- */
.divider {
  border: none;
  border-top: 1px solid var(--border-color);
  margin-block: var(--size-4);
}

/* --- Selection --- */
::selection {
  background: var(--brand-warm-light);
  color: var(--brand-warm-dark);
}