/* ============================================
   HEADER — reusable across pages
   ============================================ */

:root {
  --hd-bg: rgba(10, 10, 11, 0.72);
  --hd-bg-solid: #0a0a0b;
  --hd-border: rgba(255, 255, 255, 0.06);
  --hd-text: #e6e6e6;
  --hd-text-dim: #8a8a92;
  --hd-accent: oklch(0.78 0.12 200);
  --hd-height: 72px;
}

/* reset for header scope */
.site-header *,
.site-header *::before,
.site-header *::after {
  box-sizing: border-box;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--hd-height);
  z-index: 999;
  background: var(--hd-bg);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s ease, background 0.3s ease;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

.site-header.scrolled {
  border-bottom-color: var(--hd-border);
}

.site-header__inner {
  max-width: 1280px;
  height: 100%;
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

/* ===== Logo ===== */
.site-header__logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--hd-text);
  font-weight: 600;
  font-size: 16px;
  letter-spacing: -0.01em;
  transition: opacity 0.2s ease;
}

.site-header__logo:hover {
  opacity: 0.75;
}

.site-header__logo-mark {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  flex-shrink: 0;
}

.site-header__logo-text {
  font-family: 'JetBrains Mono', monospace;
  font-size: 14px;
  letter-spacing: -0.02em;
}

/* prevent logo text from breaking into multiple lines */
.site-header__logo-text {
  white-space: nowrap;
}

/* ===== Nav ===== */
.site-header__nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

/* keep items on single row by default; enable scrolling via media query */
.site-header__nav {
  white-space: nowrap; /* keep items on single row for scrolling when active */
}

/* subtle horizontal scrollbar for nav (matches dark theme) */
.site-header__nav::-webkit-scrollbar {
  height: 6px;
}
.site-header__nav::-webkit-scrollbar-track {
  background: transparent;
}
.site-header__nav::-webkit-scrollbar-thumb {
  background: rgba(255,255,255,0.06);
  border-radius: 6px;
  transition: background 0.18s ease;
}
.site-header__nav:hover::-webkit-scrollbar-thumb {
  background: rgba(255,255,255,0.12);
}
.site-header__nav {
  -ms-overflow-style: auto; /* show scrollbar on IE/Edge */
  scrollbar-width: thin; /* Firefox */
  scrollbar-color: rgba(255,255,255,0.06) transparent;
}

.site-header__link {
  position: relative;
  padding: 8px 14px;
  font-size: 14px;
  font-weight: 450;
  color: var(--hd-text-dim);
  text-decoration: none;
  border-radius: 8px;
  transition: color 0.2s ease, background 0.2s ease;
}

/* keep nav items on a single line */
.site-header__link {
  white-space: nowrap;
}

.site-header__link:hover {
  color: var(--hd-text);
  background: rgba(255, 255, 255, 0.04);
}

.site-header__link.is-active {
  color: var(--hd-text);
}

.site-header__link.is-active::after {
  content: '';
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 2px;
  height: 1px;
  background: var(--hd-accent);
  border-radius: 1px;
}

/* ===== CTA on right (optional slot) ===== */
.site-header__cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  font-size: 13px;
  font-weight: 500;
  color: #0a0a0b;
  background: var(--hd-text);
  border: none;
  border-radius: 8px;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.15s ease, opacity 0.2s ease;
}

/* ensure CTA text doesn't wrap (keeps arrow on same line) */
.site-header__cta {
  white-space: nowrap;
}

.site-header__cta:hover {
  opacity: 0.88;
  transform: translateY(-1px);
}

/* ===== Mobile toggle ===== */
.site-header__toggle {
  display: none;
  width: 40px;
  height: 40px;
  background: transparent;
  border: 1px solid var(--hd-border);
  border-radius: 8px;
  cursor: pointer;
  padding: 0;
  position: relative;
}

.site-header__toggle span {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 16px;
  height: 1.5px;
  background: var(--hd-text);
  border-radius: 2px;
  transform: translate(-50%, -50%);
  transition: transform 0.25s ease, opacity 0.2s ease;
}

.site-header__toggle span:nth-child(1) {
  transform: translate(-50%, calc(-50% - 5px));
}

.site-header__toggle span:nth-child(3) {
  transform: translate(-50%, calc(-50% + 5px));
}

.site-header__toggle.is-open span:nth-child(1) {
  transform: translate(-50%, -50%) rotate(45deg);
}

.site-header__toggle.is-open span:nth-child(2) {
  opacity: 0;
}

.site-header__toggle.is-open span:nth-child(3) {
  transform: translate(-50%, -50%) rotate(-45deg);
}

/* ===== Mobile menu ===== */
.site-header__mobile {
  position: fixed;
  top: var(--hd-height);
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(180deg, var(--hd-bg-solid) 0%, rgba(10, 10, 11, 0.98) 100%);
  z-index: 998;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s ease, visibility 0.25s ease;
  overflow: hidden;
  justify-content: space-around;
}

.site-header__mobile.is-open {
  opacity: 1;
  visibility: visible;
}

.site-header__mobile a {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  font-size: 15px;
  font-weight: 500;
  color: var(--hd-text);
  text-decoration: none;
  padding: 0 20px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  letter-spacing: -0.01em;
  transition: padding 0.2s ease, color 0.2s ease, background 0.2s ease;
  position: relative;
  flex: 1;
}

.site-header__mobile a:hover {
  color: var(--hd-accent);
  background: rgba(255, 255, 255, 0.02);
  padding-left: 28px;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .site-header__inner {
    padding: 0 20px;
  }

  .site-header__nav,
  .site-header__cta {
    display: none;
  }

  .site-header__toggle {
    display: block;
  }
}

/* enable nav horizontal scrolling on narrower desktops/tablets */
@media (max-width: 1100px) {
  .site-header__nav {
    overflow-x: auto;
    overflow-y: hidden;
    -webkit-overflow-scrolling: touch;
    touch-action: pan-x;
    scroll-behavior: smooth;
    padding-bottom: 6px; /* give space if scrollbar appears */
  }
}

/* spacer so page content doesn't sit under fixed header */
.site-header-spacer {
  height: var(--hd-height);
}