/* ==========================================================================
   Layout — page shell, header, sidebar, content grid, responsive rules
   ========================================================================== */

.page-shell {
  display: grid;
  grid-template-columns: var(--sidebar-width) minmax(0, 1fr);
  min-height: 100vh;
}

/* ---- Header --------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: var(--sidebar-width) minmax(0, 1fr);
  height: var(--header-height);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}

.site-header__brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding-inline: var(--space-5);
  font-family: var(--font-display);
  font-weight: var(--weight-semibold);
  font-size: 1.05rem;
  color: var(--color-text);
  text-decoration: none;
  border-right: 1px solid var(--color-border);
}

.site-header__brand:hover {
  color: var(--color-text);
}

.site-header__mark {
  width: 26px;
  height: 26px;
  flex-shrink: 0;
}

.site-header__version {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-medium);
  color: var(--color-text-faint);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  padding: 1px 7px;
  line-height: 1.6;
  flex-shrink: 0;
}

@media (max-width: 480px) {
  .site-header__version {
    display: none;
  }
}

.site-header__bar {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding-inline: var(--space-5);
  min-width: 0;
}

.site-header__menu-toggle {
  display: none;
}

.site-header__actions {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* ---- Sidebar ---------------------------------------------------------*/
.sidebar {
  grid-row: 2;
  grid-column: 1;
  border-right: 1px solid var(--color-border);
  background: var(--color-surface);
  align-self: start;
  position: sticky;
  top: var(--header-height);
  height: calc(100vh - var(--header-height));
  overflow-y: auto;
  padding: var(--space-5) var(--space-3) var(--space-8);
}

.sidebar__group + .sidebar__group {
  margin-top: var(--space-5);
}

/* ---- Main content ------------------------------------------------------*/
.main {
  grid-row: 2;
  grid-column: 2;
  min-width: 0;
  padding: var(--space-7) var(--space-6) var(--space-9);
}

.content-column {
  max-width: var(--content-width);
  margin-inline: auto;
}

.content-column--wide {
  max-width: var(--content-width-wide);
}

/* ---- Dashboard grid ----------------------------------------------------*/
.dashboard {
  max-width: var(--content-width-wide);
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-7);
}

.dashboard__grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: var(--space-6);
  align-items: start;
}

@media (max-width: 900px) {
  .dashboard__grid {
    grid-template-columns: 1fr;
  }
}

/* ---- Hero (homepage only): faint coordinate-grid texture, restrained --*/
.hero {
  position: relative;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background-color: var(--color-surface);
  background-image: linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 28px 28px;
  padding: var(--space-8) var(--space-7);
  overflow: hidden;
}

.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(
    120% 100% at 0% 0%,
    var(--color-surface) 15%,
    transparent 70%
  );
  pointer-events: none;
}

.hero__mascot {
  position: absolute;
  top: var(--space-6);
  right: var(--space-6);
  width: 104px;
  height: auto;
  z-index: 2;
}

@media (max-width: 700px) {
  .hero__mascot {
    width: 64px;
    top: var(--space-4);
    right: var(--space-4);
  }
}

.hero__inner {
  position: relative;
  max-width: 620px;
}

/* ---- Doc layout: reading column + sticky right table of contents ------*/
.doc-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--toc-width);
  gap: var(--space-7);
  max-width: calc(var(--content-width) + var(--toc-width) + var(--space-7));
  margin-inline: auto;
  align-items: start;
}

.doc-layout__toc {
  position: sticky;
  top: calc(var(--header-height) + var(--space-6));
}

@media (max-width: 1080px) {
  .doc-layout {
    grid-template-columns: minmax(0, 1fr);
    max-width: var(--content-width);
  }
  .doc-layout__toc {
    display: none;
  }
}

/* ---- Footer ------------------------------------------------------------*/
.site-footer {
  grid-column: 1 / -1;
  border-top: 1px solid var(--color-border);
  padding: var(--space-6) var(--space-6);
  color: var(--color-text-muted);
  font-size: var(--text-small);
}

.site-footer__inner {
  max-width: var(--content-width-wide);
  margin-inline: auto;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  justify-content: space-between;
}

/* ---- Responsive: tablet -------------------------------------------------*/
@media (max-width: 1080px) {
  :root {
    --sidebar-width: 240px;
  }
  .main {
    padding: var(--space-6) var(--space-5) var(--space-8);
  }
}

/* ---- Responsive: mobile / sidebar becomes a drawer ----------------------*/
@media (max-width: 820px) {
  .page-shell {
    grid-template-columns: 1fr;
  }

  .site-header {
    grid-template-columns: auto 1fr;
  }

  .site-header__brand {
    border-right: none;
    padding-inline: var(--space-4);
  }

  .site-header__bar {
    padding-inline: var(--space-4);
  }

  .site-header__menu-toggle {
    display: inline-flex;
  }

  .sidebar {
    position: fixed;
    top: var(--header-height);
    left: 0;
    height: calc(100vh - var(--header-height));
    width: min(300px, 84vw);
    transform: translateX(-100%);
    transition: transform var(--duration-base) var(--ease-standard);
    z-index: var(--z-drawer);
    box-shadow: var(--shadow-lg);
  }

  .sidebar.is-open {
    transform: translateX(0);
  }

  .sidebar-overlay {
    display: none;
    position: fixed;
    inset: var(--header-height) 0 0 0;
    background: rgba(10, 12, 16, 0.4);
    z-index: calc(var(--z-drawer) - 1);
  }

  .sidebar-overlay.is-visible {
    display: block;
  }

  .main {
    grid-column: 1;
    padding: var(--space-6) var(--space-4) var(--space-8);
  }

  .hero {
    padding: var(--space-6) var(--space-5);
  }
}

@media (max-width: 560px) {
  .dashboard {
    gap: var(--space-6);
  }
}