/* Shared public-site header. Keep this file page-agnostic so every
   visitor-facing route uses the same lockup, navigation, and breakpoint. */
.site-header {
  --header-ink: #0A0A0A;
  --header-paper: #F4F4F2;
  --header-ash: #B7B7B4;
  --header-line: rgba(255, 255, 255, 0.14);
  --header-ease: cubic-bezier(0.22, 1, 0.36, 1);
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  color: var(--header-paper);
  background: rgba(10, 10, 10, 0.94);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--header-ease);
}

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

.site-header .header-inner {
  display: flex;
  width: 100%;
  max-width: 1280px;
  height: 64px;
  margin: 0 auto;
  padding: 0 28px;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.site-header .brand {
  display: inline-flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 11px;
  color: var(--header-paper);
  text-decoration: none;
}

.site-header .coin-nav {
  display: flex;
  width: 26px;
  height: 26px;
  flex: none;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: #000;
  color: #fff;
  line-height: 1;
}

.site-header .coin-nav .glyph {
  font-family: 'IBM Plex Sans JP', 'Hiragino Kaku Gothic ProN', 'Yu Gothic', sans-serif;
  font-size: 14px;
  font-weight: 500;
  line-height: 1;
}

.site-header .brand-name {
  font-family: 'IBM Plex Sans', -apple-system, 'Helvetica Neue', Arial, sans-serif;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.site-header .site-nav {
  display: flex;
  min-width: 0;
  margin-left: auto;
  align-items: center;
  gap: clamp(18px, 1.8vw, 28px);
}

.site-header .site-nav a {
  color: var(--header-ash);
  font-family: 'IBM Plex Sans', -apple-system, 'Helvetica Neue', Arial, sans-serif;
  font-size: 14px;
  font-weight: 500;
  line-height: 1.3;
  text-decoration: none;
  white-space: nowrap;
  background-image: linear-gradient(currentColor, currentColor);
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 0 1px;
  padding-bottom: 3px;
  transition: color 0.2s var(--header-ease), background-size 0.3s var(--header-ease);
}

.site-header .site-nav a:hover,
.site-header .site-nav a[aria-current='page'],
.site-header .site-nav a.is-section-active {
  color: var(--header-paper);
  background-size: 100% 1px;
}

.site-header .site-nav a.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 9px 18px;
  border: 1px solid transparent;
  border-radius: 2px;
  background: var(--header-paper);
  background-image: none;
  color: var(--header-ink);
  font-weight: 600;
  transition: transform 0.2s var(--header-ease), background 0.2s var(--header-ease);
}

.site-header .site-nav a.btn:hover,
.site-header .site-nav a.btn[aria-current='page'],
.site-header .site-nav a.btn.is-section-active {
  color: var(--header-ink);
  background: #fff;
  transform: translateY(-1px);
}

.site-header a:focus-visible,
.site-header .nav-toggle:focus-visible {
  outline: 2px solid var(--header-paper);
  outline-offset: 3px;
}

.site-header .nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  flex: 0 0 auto;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 10px;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.site-header .nav-toggle span {
  width: 100%;
  height: 2px;
  border-radius: 2px;
  background: var(--header-paper);
  transition: transform 0.25s var(--header-ease), opacity 0.2s var(--header-ease);
}

.site-header .nav-toggle[aria-expanded='true'] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.site-header .nav-toggle[aria-expanded='true'] span:nth-child(2) { opacity: 0; }
.site-header .nav-toggle[aria-expanded='true'] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.site-header + #main-content[data-header-offset] { padding-top: 64px; }

@media (max-width: 1199px) {
  .site-header .nav-toggle { display: flex; }

  .site-header .site-nav {
    position: absolute;
    top: 64px;
    right: 0;
    left: 0;
    display: flex;
    max-height: calc(100dvh - 64px);
    margin: 0;
    padding: 12px 28px 24px;
    overflow-y: auto;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: rgba(10, 10, 10, 0.98);
    border-bottom: 1px solid var(--header-line);
    clip-path: inset(0 0 100% 0);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transition: clip-path 0.3s var(--header-ease), opacity 0.2s var(--header-ease), visibility 0s linear 0.3s;
  }

  .site-header .site-nav.open {
    clip-path: inset(0);
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transition-delay: 0s;
  }

  .site-header .site-nav a {
    padding: 14px 0;
    border-bottom: 1px solid var(--header-line);
    background-image: none;
  }

  .site-header .site-nav a.btn {
    min-height: 44px;
    margin-top: 14px;
    border-bottom: 0;
  }
}

@media (max-width: 480px) {
  .site-header .header-inner { padding: 0 20px; }
  .site-header .site-nav { padding-right: 20px; padding-left: 20px; }
}

@media (prefers-reduced-motion: reduce) {
  .site-header,
  .site-header .site-nav,
  .site-header .site-nav a,
  .site-header .nav-toggle span { transition: none; }
}