/* ============================================
   STYLE — Base, layout, header, nav
   ============================================ */

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  transition: background var(--dur-base) var(--ease), color var(--dur-base) var(--ease);
  overflow-x: hidden;
}

.container {
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-4);
}

section { padding-block: var(--space-7); }

.section-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--space-2);
}

.section-eyebrow::before {
  content: "";
  width: 20px;
  height: 1px;
  background: var(--accent);
}

.section-title {
  font-family: var(--font-display);
  text-transform: uppercase;
  font-size: var(--fs-3xl);
  letter-spacing: -0.01em;
  margin-bottom: var(--space-5);
  max-width: 20ch;
}

.section-title span { color: var(--accent); }

/* --- Skip link --- */
.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--accent);
  color: #0a0a0a;
  padding: var(--space-2) var(--space-3);
  z-index: 999;
  font-weight: 600;
}
.skip-link:focus {
  left: var(--space-3);
  top: var(--space-3);
}

/* --- Focus visibility (accessibility) --- */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* ============ HEADER ============ */
.site-header {
  position: fixed;
  inset-inline: 0;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: var(--border-w) solid var(--border);
  transition: background var(--dur-base) var(--ease), border-color var(--dur-base) var(--ease);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.nav-desktop {
  display: none;
}

.nav-desktop ul {
  display: flex;
  gap: var(--space-5);
}

.nav-desktop a {
  font-size: var(--fs-sm);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-muted);
  position: relative;
  padding-block: var(--space-1);
  transition: color var(--dur-fast) var(--ease);
}

.nav-desktop a:hover,
.nav-desktop a:focus-visible { color: var(--text); }

.nav-desktop a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width var(--dur-base) var(--ease);
}

.nav-desktop a:hover::after,
.nav-desktop a:focus-visible::after { width: 100%; }

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-left: auto;
}

/* --- Theme toggle --- */
.theme-toggle {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: var(--border-w) solid var(--border);
  display: grid;
  place-items: center;
  color: var(--text);
  transition: border-color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}
.theme-toggle:hover { border-color: var(--accent); transform: rotate(15deg); }
.theme-toggle svg { width: 18px; height: 18px; }
.theme-toggle .icon-moon { display: none; }
[data-theme="light"] .theme-toggle .icon-sun { display: none; }
[data-theme="light"] .theme-toggle .icon-moon { display: block; }

/* --- Language toggle --- */
.lang-toggle {
  display: flex;
  border: var(--border-w) solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
}
.lang-toggle button {
  padding: var(--space-1) var(--space-2);
  color: var(--text-muted);
  font-weight: 600;
  transition: background var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease);
}
.lang-toggle button.active {
  background: var(--accent);
  color: #0a0a0a;
}

/* --- Mobile menu button --- */
.menu-toggle {
  display: grid;
  width: 40px;
  height: 40px;
  place-items: center;
  color: var(--text);
}
.menu-toggle svg { width: 22px; height: 22px; }

@media (min-width: 860px) {
  .nav-desktop { display: block; }
  .menu-toggle { display: none; }
}

/* --- Mobile nav panel --- */
.nav-mobile {
  position: fixed;
  inset: 72px 0 0 0;
  background: var(--bg);
  z-index: 99;
  padding: var(--space-5) var(--space-4);
  transform: translateY(-8px);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--dur-base) var(--ease), transform var(--dur-base) var(--ease), visibility var(--dur-base);
}
.nav-mobile.open {
  opacity: 1;
  transform: translateY(0);
  visibility: visible;
}
.nav-mobile ul { display: flex; flex-direction: column; gap: var(--space-4); }
.nav-mobile a {
  font-family: var(--font-display);
  text-transform: uppercase;
  font-size: var(--fs-xl);
}

@media (min-width: 860px) {
  .nav-mobile { display: none; }
}

/* ============ BUTTONS ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.85rem 1.6rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: var(--fs-sm);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  border: var(--border-w) solid transparent;
  transition: transform var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
  white-space: nowrap;
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn-primary {
  background: var(--accent);
  color: #0a0a0a;
}
.btn-primary:hover {
  background: var(--accent-hover);
  box-shadow: var(--shadow-glow);
}

.btn-outline {
  border-color: var(--border);
  color: var(--text);
}
.btn-outline:hover { border-color: var(--accent); color: var(--accent); }

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

.btn-sm { padding: 0.55rem 1.1rem; font-size: var(--fs-xs); }

.btn svg { width: 16px; height: 16px; }

.btn[disabled] { opacity: 0.5; cursor: not-allowed; transform: none !important; }