/* ─── Site header (glass); PDF tabs share 2-col grid with main preview layout ─ */
/* --header-glass-fill: 1 at PDF scroll top, lower while scrolling (set from index.html) */
.site-header {
  position: relative;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  background: transparent;
  backdrop-filter: blur(10px) saturate(1.1);
  -webkit-backdrop-filter: blur(10px) saturate(1.1);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.04);
}

.site-header::before {
  content: '';
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background: linear-gradient(
    180deg,
    rgba(8, 14, 30, 0.58) 0%,
    rgba(8, 14, 30, 0.42) 55%,
    rgba(8, 14, 30, 0.35) 100%
  );
  opacity: var(--header-glass-fill, 1);
  transition: opacity 0.35s ease;
}

.site-header-inner {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* Header wordmark: single line by default; stacked eyebrow + title in PDF preview */
.site-header-brand-stack {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.15rem;
  line-height: 1.15;
}

.site-header-brand-eyebrow {
  display: none;
  font-size: 0.52rem;
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: rgba(125, 211, 252, 0.78);
  line-height: 1;
  text-shadow: 0 0 20px rgba(56, 189, 248, 0.35);
}

.site-header-brand-titles {
  display: block;
}

.site-header-brand-title {
  font-weight: 700;
  letter-spacing: -0.02em;
}

.site-header-brand-title--default {
  display: inline-block;
}

.site-header-brand-title--preview {
  display: none;
  font-size: 1.0625rem;
  filter: drop-shadow(0 0 16px rgba(56, 189, 248, 0.28));
}

@media (min-width: 640px) {
  .site-header-brand-title--preview {
    font-size: 1.1875rem;
  }
}

body.preview-mode-active:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-brand-eyebrow {
  display: block;
}

body.preview-mode-active:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-brand-title--default {
  display: none;
}

body.preview-mode-active:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-brand-title--preview {
  display: inline-block;
}

/* Wordmark block centered over the left column; text left-aligned inside the block */
body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-brand {
  display: flex;
  justify-content: center;
  align-items: center;
  justify-self: stretch;
  width: 100%;
  min-width: 0;
}

body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-brand-stack {
  align-items: flex-start;
  text-align: left;
  width: max-content;
  max-width: 100%;
}

.site-header-preview-col {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  margin-left: auto;
  flex: 1 1 auto;
  min-width: 0;
  position: relative;
  gap: 0.75rem;
}

.site-header-middle {
  display: none;
  flex: 1 1 auto;
  min-width: 0;
  align-items: center;
  justify-content: center;
}

.site-header-middle:has(#pdf-tab-bar-wrap:not([hidden])) {
  display: flex;
}

@media (min-width: 1024px) {
  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) {
    display: grid;
    grid-template-columns: minmax(0, 19rem) minmax(0, 1fr);
    gap: 1rem;
    align-items: center;
  }

  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-brand {
    grid-column: 1;
  }

  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-preview-col {
    grid-column: 2;
    position: relative;   /* anchor for absolutely-positioned nav */
    margin-left: 0;
    flex: unset;
    width: 100%;
    min-width: 0;
    min-height: 2.75rem;
    display: flex;
    align-items: center;
  }

  /* Middle stretches across the full preview column so the tab track centres
     over the PDF pane, not just the space left after the nav. */
  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-middle {
    flex: 1 1 0;
    display: flex;
    align-items: center;
    min-width: 0;
    width: 100%;
  }

  /* Nav floats at the right edge; doesn't consume layout space. */
  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-nav {
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    margin-left: 0;
  }
}

@media (max-width: 1023px) {
  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) {
    display: grid;
    grid-template-columns: 1fr auto;
    grid-template-rows: auto auto;
    gap: 0.5rem 1rem;
    align-items: center;
  }

  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-brand {
    grid-column: 1;
    grid-row: 1;
  }

  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-preview-col {
    display: contents;
  }

  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-nav {
    grid-column: 2;
    grid-row: 1;
    margin-left: 0;
  }

  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-middle {
    grid-column: 1 / -1;
    grid-row: 2;
    flex: unset;
    justify-content: stretch;
    width: 100%;
    min-width: 0;
  }
}

/* ─── Mobile header: 2-row layout on phones narrower than 480 px ─── */
/* Scoped to non-preview so the preview-mode grid layout is unaffected   */
@media (max-width: 479px) {
  body:not(.preview-mode-active) .site-header-inner {
    flex-wrap: wrap;
    padding-top: 0.625rem;
    padding-bottom: 0.625rem;
    row-gap: 0.375rem;
  }
  body:not(.preview-mode-active) .site-header-inner .site-header-brand {
    flex: 0 0 100%;
  }
  body:not(.preview-mode-active) .site-header-inner .site-header-preview-col {
    flex: 0 0 100%;
    margin-left: 0;
    justify-content: center;
  }
}

/* ─── Preview mode header on portrait phones: brand hidden, nav row 1, tabs row 2 ─── */
@media (max-width: 479px) {
  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) {
    grid-template-columns: 1fr;
  }
  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-brand {
    display: none;
  }
  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-nav {
    grid-column: 1;
    grid-row: 1;
    justify-self: end;
    margin-left: 0;
  }
  body.preview-mode-active .site-header-inner:has(#pdf-tab-bar-wrap:not([hidden])) .site-header-middle {
    grid-column: 1;
    grid-row: 2;
  }
}