/* Reusable components: nav, buttons, cards, forms, footer. */

.site-nav {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-sm) var(--space-md);
  background: color-mix(in srgb, var(--color-paper) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
}

.site-nav__brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--step-1);
  text-decoration: none;
  color: var(--color-ink);
}

.site-nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-nav__links a:not(.btn) {
  position: relative;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  text-decoration: none;
  font-size: var(--step--1);
  color: var(--color-muted);
  transition: color 160ms ease;
}

.site-nav__links a:not(.btn)::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 10px;
  width: 100%;
  height: 1px;
  background: var(--color-primary);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 220ms cubic-bezier(0.16, 1, 0.3, 1);
}

.site-nav__links a:not(.btn):hover {
  color: var(--color-ink);
}

.site-nav__links a:not(.btn):hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.site-nav__links .btn {
  font-size: var(--step--1);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  padding: 0.75rem 1.4rem;
  font-size: var(--step--1);
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.btn:active {
  transform: translateY(1px) scale(0.98);
}

.btn--primary {
  background: var(--color-primary);
  color: white;
}

.btn--primary:hover {
  background: var(--color-primary-bright);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.btn--accent {
  background: var(--color-accent);
  color: white;
}

.btn--accent:hover {
  background: var(--color-accent-bright);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.btn--ghost {
  background: transparent;
  border-color: var(--color-border);
  color: var(--color-ink);
}

.btn--ghost:hover {
  border-color: var(--color-primary);
  transform: translateY(-2px);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-md);
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  font-size: var(--step--1);
  font-weight: 600;
  margin-bottom: var(--space-sm);
}

.field input,
.field select,
.field textarea {
  font: inherit;
  font-weight: 400;
  padding: 0.7rem 0.85rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-ink);
  transition: border-color 200ms ease, box-shadow 200ms ease;
}

.field input:focus,
.field select:focus,
.field textarea:focus {
  border-color: var(--color-primary-bright);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-primary) 15%, transparent);
  outline: none;
}

.field input:focus-visible,
.field select:focus-visible,
.field textarea:focus-visible,
.btn:focus-visible {
  outline: 2px solid var(--color-primary-bright);
  outline-offset: 2px;
}

.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-lg) var(--space-md);
}

.site-footer__grid {
  max-width: var(--max-content);
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-lg);
  justify-content: space-between;
}

.site-footer a {
  text-decoration: none;
  color: var(--color-muted);
  font-size: var(--step--1);
}

.site-footer a:hover {
  color: var(--color-ink);
}

.site-footer__cols {
  display: flex;
  gap: var(--space-xl);
  flex-wrap: wrap;
}

.site-footer__col {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.lang-toggle {
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background: transparent;
  color: var(--color-muted);
  font-family: var(--font-mono);
  font-size: var(--step--1);
  font-weight: 600;
  padding: 0.35rem 0.7rem;
  cursor: pointer;
  transition: border-color 160ms ease, color 160ms ease, transform 160ms ease;
}

.lang-toggle:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  transform: translateY(-1px);
}

.lang-toggle:active {
  transform: translateY(0);
}

@media (max-width: 640px) {
  .site-nav__links li:not(:last-child):not(#langToggleSlot) {
    display: none;
  }
  .site-nav__brand-text {
    display: none;
  }
}