/**
 * layout.css
 * -----------------------------------------------------------------------
 * Page-level structure: top nav, the two-column app shell (viewer +
 * sidebar), and the bottom summary bar, plus responsive behavior.
 *
 * RESPONSIVE PATTERN (flagged per request):
 * On viewports narrower than 900px the right sidebar becomes a bottom
 * SHEET/DRAWER that slides up over the canvas, collapsed by default
 * behind a "BUILD YOUR TROLLEY" toggle bar docked above the summary bar.
 * This keeps the full-height 3D canvas as the primary mobile view (which
 * is what a "3D viewer first" configurator wants) instead of pushing the
 * whole sidebar into the document flow below a short canvas. It's the
 * same pattern used by most mobile product configurators (Nike By You,
 * YETI). If you'd rather have the sidebar just stack below the canvas
 * in normal flow, that's a smaller change — say the word.
 * ----------------------------------------------------------------------- */

/* ============================ TOP NAV ============================ */

.topnav {
  position: sticky;
  top: 0;
  z-index: var(--z-nav);
  height: var(--topnav-height);
  display: flex;
  align-items: center;
  gap: var(--space-5);
  padding: 0 var(--space-6);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}

.topnav__logo {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: var(--tracking-wider);
  white-space: nowrap;
}

.topnav__links {
  flex: 1;
  display: flex;
  justify-content: center;
  gap: var(--space-6);
}

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

.topnav__menu-toggle {
  display: none;
  margin-left: auto;
}

/* ============================ APP SHELL ============================ */

.app-shell {
  display: grid;
  grid-template-columns: 1fr var(--sidebar-width);
  grid-template-rows: minmax(0, 1fr);
  align-items: stretch;
  height: calc(100vh - var(--topnav-height) - var(--summary-bar-height));
}

/* --------------------------- VIEWER --------------------------- */

.viewer {
  position: relative;
  display: flex;
  flex-direction: column;
  background: var(--color-surface-alt);
  padding: var(--space-6);
  min-height: 0;
  overflow-y: auto;
}

.viewer__stage {
  position: relative;
  flex: 1;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 320px;
  overflow: hidden; /* clip the mounted <canvas> to the stage's rounded corners */
}

.thumbnail-strip {
  display: flex;
  gap: var(--space-3);
  margin-top: var(--space-5);
  overflow-x: auto;
  padding-bottom: var(--space-1);
}

/* ------------------------- SIDEBAR PANEL ------------------------ */

.sidebar {
  display: flex;
  flex-direction: column;
  background: var(--color-surface);
  border-left: 1px solid var(--color-border);
  min-height: 0;
  height: 100%;
}

.sidebar__scroll {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  padding: 0 var(--space-5) var(--space-6);
}

.sidebar-toggle,
.sidebar__header,
.sidebar__close,
.sidebar-backdrop {
  display: none;
}

/* ============================ SUMMARY BAR ============================ */

.summary-bar {
  position: sticky;
  bottom: 0;
  z-index: var(--z-summary);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-5);
  min-height: var(--summary-bar-height);
  padding: var(--space-4) var(--space-6);
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
}

.summary-bar__selections {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  flex: 1;
  min-width: 0;
}

.summary-bar__right {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  flex-shrink: 0;
}

.summary-bar__price {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  margin-right: var(--space-2);
}

/* ============================ BREAKPOINTS ============================ */

/* Tablet: narrow the sidebar before collapsing it entirely.
   (The swatch-grid column-count override for this range lives in
   components.css, next to .swatch-grid's base rule — components.css
   loads after this file, so a same-specificity override placed here
   would lose the cascade to its unconditional base rule regardless of
   this media query matching.) */
@media (max-width: 1140px) {
  :root {
    --sidebar-width: 320px;
  }
}

@media (max-width: 900px) {
  .topnav {
    padding: 0 var(--space-4);
  }

  .topnav__menu-toggle {
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    gap: 4px;
    width: 32px;
    height: 32px;
    order: 3;
  }

  .topnav__menu-toggle span {
    display: block;
    height: 2px;
    background: var(--color-ink);
    border-radius: 2px;
  }

  .topnav__links {
    position: absolute;
    top: var(--topnav-height);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--duration-med) var(--ease-standard);
  }

  .topnav__links.is-open {
    max-height: 320px;
  }

  .topnav__links .topnav__link {
    width: 100%;
    padding: var(--space-4) var(--space-5);
    border-bottom: 1px solid var(--color-border);
  }

  /* --- app shell becomes a single full-bleed canvas column --- */
  .app-shell {
    grid-template-columns: 1fr;
    position: relative;
  }

  .viewer {
    min-height: calc(100vh - var(--topnav-height) - var(--summary-bar-height));
    padding: var(--space-4);
    padding-bottom: calc(var(--space-4) + var(--sidebar-toggle-height));
  }

  /* --- sidebar becomes a bottom sheet, hidden off-screen by default --- */
  .sidebar-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    position: fixed;
    left: 0;
    right: 0;
    bottom: var(--summary-bar-height);
    z-index: var(--z-sidebar);
    width: 100%;
    height: var(--sidebar-toggle-height);
    padding: 0 var(--space-4);
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
    font-weight: 600;
    letter-spacing: var(--tracking-wide);
    font-size: 0.85rem;
  }

  .sidebar-toggle svg {
    transition: transform var(--duration-fast) var(--ease-standard);
  }

  .sidebar-toggle[aria-expanded="true"] svg {
    transform: rotate(180deg);
  }

  .sidebar {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: var(--z-sidebar);
    max-height: 82vh;
    border-left: none;
    border-top: 1px solid var(--color-border);
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
    box-shadow: var(--shadow-lg);
    transform: translateY(100%);
    transition: transform var(--duration-med) var(--ease-standard);
  }

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

  .sidebar__header {
    display: flex;
  }

  .sidebar__close {
    display: inline-flex;
  }

  .sidebar-backdrop {
    position: fixed;
    inset: 0;
    z-index: calc(var(--z-sidebar) - 1);
    background: rgba(15, 15, 17, 0.4);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--duration-med) var(--ease-standard);
  }

  .sidebar-backdrop.is-open {
    display: block;
    opacity: 1;
    pointer-events: auto;
  }

  .summary-bar {
    flex-wrap: wrap;
    padding: var(--space-3) var(--space-4);
  }

  /* Chips scroll horizontally in one row instead of wrapping to several —
     keeps the bar compact and matches how the thumbnail strip above it
     already behaves, rather than pushing price/actions further down. */
  .summary-bar__selections {
    order: 2;
    width: 100%;
    flex-wrap: nowrap;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    padding-bottom: var(--space-1); /* room for the scrollbar so it doesn't sit on the chips */
  }

  .summary-bar__right {
    order: 1;
    width: 100%;
    justify-content: space-between;
  }
}

/* Narrow enough that price + SHARE DESIGN + ADD TO BAG no longer fit in
   one row — stack price above a full-width actions row instead of
   wrapping (which used to just hide SHARE DESIGN entirely; restored
   below since hiding a whole feature by screen width isn't a great
   pattern). Each button gets equal width, both stay reachable. */
@media (max-width: 560px) {
  .summary-bar__right {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-3);
  }

  .summary-bar__price {
    flex-direction: row;
    align-items: baseline;
    justify-content: space-between;
    width: 100%;
    margin-right: 0;
  }

  .summary-bar__actions .btn {
    flex: 1;
  }
}