/* ============================================================
   LAYOUT - App shell, navigation, side sheet, overlays
   ============================================================ */

:root {
  --topnav-height: 68px;
  --page-gutter: var(--sp-24);
  --safe-top: env(safe-area-inset-top, 0px);
  --safe-left: env(safe-area-inset-left, 0px);
  --safe-right: env(safe-area-inset-right, 0px);
  --safe-bottom: env(safe-area-inset-bottom, 0px);
}

#app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
}

.topnav {
  position: sticky;
  top: 0;
  z-index: var(--z-nav);
  display: flex;
  align-items: center;
  gap: var(--sp-16);
  min-height: var(--topnav-height);
  padding: 0 var(--sp-24);
  background: var(--surface-glass-heavy);
  border-bottom: 1px solid var(--border-subtle);
  backdrop-filter: blur(16px) saturate(1.2);
  -webkit-backdrop-filter: blur(16px) saturate(1.2);
}

.topnav__left {
  display: flex;
  align-items: center;
  gap: var(--sp-16);
  min-width: 0;
  flex-shrink: 0;
}

.topnav__brand {
  display: flex;
  align-items: baseline;
  gap: var(--sp-8);
  font-family: var(--font-display);
  font-size: var(--text-md);
  font-weight: 650;
  color: var(--text-primary);
  letter-spacing: var(--tracking-tight);
  white-space: nowrap;
}

.topnav__brand-accent {
  color: var(--text-secondary);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 500;
}

.topnav__divider {
  width: 1px;
  height: 24px;
  background: var(--border-default);
}

.topnav__links {
  display: flex;
  align-items: center;
  gap: var(--sp-4);
  min-width: 0;
  flex: 1;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--text-secondary);
  padding: 7px var(--sp-12);
  border-radius: var(--radius-full);
  border: 1px solid transparent;
  background: transparent;
  cursor: pointer;
  transition: all var(--duration-micro) var(--ease-standard);
  white-space: nowrap;
  text-decoration: none;
}

.nav-link:hover {
  color: var(--text-primary);
  border-color: var(--border-subtle);
  background: rgba(255, 255, 255, 0.06);
}

.nav-link.is-active {
  color: var(--accent);
  background: var(--accent-dim);
  border-color: var(--border-accent);
}

.topnav__actions {
  display: flex;
  align-items: center;
  gap: var(--sp-12);
  margin-left: auto;
  flex-shrink: 0;
}

.kbd-hint {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-4);
  font-size: var(--text-xs);
  color: var(--text-tertiary);
  padding: var(--sp-4) var(--sp-8);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--duration-micro) var(--ease-standard);
  background: rgba(255, 255, 255, 0.04);
}

.kbd-hint:hover {
  border-color: var(--border-strong);
  color: var(--text-secondary);
  background: rgba(255, 255, 255, 0.08);
}

.kbd-hint kbd {
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  font-weight: 700;
  background: rgba(255, 255, 255, 0.1);
  padding: 1px 5px;
  border-radius: 4px;
}

.topnav__status {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-8);
  margin-left: var(--sp-8);
}

.topnav__status-label {
  font-size: var(--text-xs);
  color: var(--text-secondary);
  font-weight: 600;
}

.topnav__status-dot {
  display: none;
}

.topnav__toggle {
  display: none;
  width: 34px;
  height: 34px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-default);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--duration-micro) var(--ease-standard);
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
}

.topnav__toggle span {
  width: 14px;
  height: 1.5px;
  border-radius: 999px;
  background: currentColor;
  transition: transform var(--duration-micro) var(--ease-standard), opacity var(--duration-micro) var(--ease-standard);
}

.topnav__toggle:hover {
  color: var(--text-primary);
  border-color: var(--border-strong);
  background: rgba(255, 255, 255, 0.08);
}

.topnav.topnav--menu-open .topnav__toggle span:nth-child(1) {
  transform: translateY(5.5px) rotate(45deg);
}

.topnav.topnav--menu-open .topnav__toggle span:nth-child(2) {
  opacity: 0;
}

.topnav.topnav--menu-open .topnav__toggle span:nth-child(3) {
  transform: translateY(-5.5px) rotate(-45deg);
}

.page-content {
  flex: 1;
  padding: var(--page-gutter);
  max-width: 1920px;
  margin: 0 auto;
  width: 100%;
}

.page-enter {
  opacity: 0;
  filter: blur(6px);
  transform: translateY(10px);
}

.page-enter-active {
  opacity: 1;
  filter: blur(0);
  transform: translateY(0);
  transition:
    opacity var(--duration-page) var(--ease-standard),
    filter var(--duration-page) var(--ease-standard),
    transform var(--duration-page) var(--ease-standard);
}

.side-sheet-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.25);
  z-index: var(--z-sheet);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--duration-overlay) var(--ease-standard);
}

.side-sheet-overlay.is-open {
  opacity: 1;
  pointer-events: auto;
}

.side-sheet {
  position: fixed;
  top: 0;
  right: 0;
  width: min(540px, 92vw);
  height: 100vh;
  height: 100dvh;
  background: var(--surface-raised);
  border-left: 1px solid var(--border-default);
  z-index: calc(var(--z-sheet) + 1);
  transform: translateX(100%);
  transition: transform var(--duration-overlay) var(--ease-standard);
  display: flex;
  flex-direction: column;
  box-shadow: -24px 0 48px rgba(15, 23, 42, 0.15);
}

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

.side-sheet__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--sp-24);
  border-bottom: 1px solid var(--border-subtle);
  background: var(--surface-muted);
  flex-shrink: 0;
}

.side-sheet__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 650;
}

.side-sheet__close {
  width: 34px;
  height: 34px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  background: transparent;
  color: var(--text-secondary);
  font-size: 1.25rem;
  cursor: pointer;
  transition: all var(--duration-micro);
}

.side-sheet__close:hover {
  background: var(--surface-muted);
  border-color: var(--border-default);
  color: var(--text-primary);
}

.side-sheet__body {
  flex: 1;
  overflow-y: auto;
  padding: var(--sp-24);
}

.side-sheet__footer {
  padding: var(--sp-16) var(--sp-24) calc(var(--sp-16) + var(--safe-bottom));
  border-top: 1px solid var(--border-subtle);
  background: var(--surface-muted);
  font-size: var(--text-sm);
  color: var(--text-secondary);
  display: flex;
  justify-content: space-between;
  flex-shrink: 0;
}

.command-palette-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.2);
  backdrop-filter: blur(6px);
  z-index: var(--z-palette);
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 14vh;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--duration-overlay) var(--ease-standard);
}

.command-palette-overlay.is-open {
  opacity: 1;
  pointer-events: auto;
}

.command-palette {
  width: min(620px, 92vw);
  background: var(--surface-raised);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  overflow: hidden;
  transform: scale(0.98) translateY(-6px);
  transition: transform var(--duration-overlay) var(--ease-standard);
}

.command-palette-overlay.is-open .command-palette {
  transform: scale(1) translateY(0);
}

.command-palette__input-wrap {
  display: flex;
  align-items: center;
  gap: var(--sp-12);
  padding: var(--sp-16) var(--sp-24);
  border-bottom: 1px solid var(--border-subtle);
}

.command-palette__icon {
  color: var(--text-tertiary);
  font-size: var(--text-lg);
  flex-shrink: 0;
}

.command-palette__input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: var(--text-md);
  font-weight: 500;
}

.command-palette__input::placeholder {
  color: var(--text-tertiary);
}

.command-palette__results {
  max-height: 380px;
  max-height: min(60dvh, 380px);
  overflow-y: auto;
  padding: var(--sp-8);
}

.command-palette__item {
  display: flex;
  align-items: center;
  gap: var(--sp-12);
  padding: var(--sp-12) var(--sp-16);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--duration-micro);
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

.command-palette__item:hover,
.command-palette__item.is-selected {
  background: var(--surface-muted);
  color: var(--text-primary);
}

.command-palette__item-type {
  font-size: var(--text-xs);
  color: var(--text-tertiary);
  padding: var(--sp-2) var(--sp-8);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  white-space: nowrap;
}

.command-palette__hint {
  padding: var(--sp-12) var(--sp-24);
  border-top: 1px solid var(--border-subtle);
  font-size: var(--text-xs);
  color: var(--text-tertiary);
  display: flex;
  gap: var(--sp-16);
}

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.24);
  backdrop-filter: blur(6px);
  z-index: var(--z-modal);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--duration-overlay) var(--ease-standard);
}

.modal-overlay.is-open {
  opacity: 1;
  pointer-events: auto;
}

.modal {
  background: var(--surface-raised);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  width: min(560px, 92vw);
  max-height: 80vh;
  max-height: 80dvh;
  box-shadow: var(--shadow-xl);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transform: scale(0.96);
  transition: transform var(--duration-overlay) var(--ease-standard);
}

.modal-overlay.is-open .modal {
  transform: scale(1);
}

.modal__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--sp-24);
  border-bottom: 1px solid var(--border-subtle);
  flex-shrink: 0;
}

.modal__title {
  font-size: var(--text-lg);
  font-family: var(--font-display);
  font-weight: 650;
}

.modal__close {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 1.25rem;
  cursor: pointer;
  transition: all var(--duration-micro);
}

.modal__close:hover {
  background: var(--surface-muted);
  color: var(--text-primary);
}

.modal__body {
  flex: 1;
  overflow-y: auto;
  padding: var(--sp-24);
}

.modal__section {
  margin-bottom: var(--sp-24);
}

.modal__section:last-child { margin-bottom: 0; }

.modal__label {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
  padding-bottom: var(--sp-4);
  margin-bottom: var(--sp-8);
  border-bottom: 1px solid var(--border-subtle);
  display: block;
}

.modal__text {
  font-size: var(--text-base);
  line-height: var(--leading-relaxed);
  color: var(--text-muted);
}

.modal__footer {
  padding: var(--sp-16) var(--sp-24);
  background: var(--surface-muted);
  font-size: var(--text-sm);
  color: var(--text-secondary);
  display: flex;
  justify-content: space-between;
  flex-shrink: 0;
}

@media (max-width: 1200px) {
  .topnav__links {
    gap: 0;
  }

  .nav-link {
    padding: var(--sp-4) var(--sp-8);
    font-size: var(--text-xs);
  }
}

@media (max-width: 900px) {
  :root {
    --page-gutter: var(--sp-16);
  }

  .topnav {
    min-height: var(--topnav-height);
    top: 0;
    margin: 0;
    padding: calc(var(--sp-12) + var(--safe-top)) calc(var(--page-gutter) + var(--safe-right)) var(--sp-12) calc(var(--page-gutter) + var(--safe-left));
    border: 1px solid var(--border-default);
    border-left: none;
    border-right: none;
    border-top: none;
    border-radius: 0;
    box-shadow: 0 10px 24px rgba(0, 0, 0, 0.22);
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    grid-template-areas:
      "brand actions"
      "links links";
    align-items: center;
    column-gap: var(--sp-12);
    row-gap: 0;
    transition: row-gap var(--duration-ui) var(--ease-standard), padding-bottom var(--duration-ui) var(--ease-standard);
  }

  .topnav__left {
    grid-area: brand;
    width: 100%;
    min-height: 40px;
    align-items: center;
    gap: var(--sp-8);
  }

  .topnav__brand {
    align-items: center;
    min-width: 0;
    max-width: min(74vw, 360px);
    overflow: hidden;
    text-overflow: ellipsis;
    font-size: clamp(0.9rem, 2.1vw, 1rem);
    font-weight: 620;
    letter-spacing: -0.02em;
    line-height: 1.1;
  }

  .topnav__brand-accent {
    display: none;
  }

  .topnav__links {
    grid-area: links;
    width: 100%;
    margin: 0;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: var(--sp-4);
    overflow: hidden;
    max-height: 0;
    opacity: 0;
    pointer-events: none;
    transform: translateY(-10px) scale(0.985);
    transform-origin: top center;
    padding: 0;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0);
    transition:
      max-height 420ms var(--ease-standard),
      opacity 240ms var(--ease-out),
      transform 360ms var(--ease-out),
      padding 300ms var(--ease-out),
      border-color 280ms var(--ease-out),
      background-color 280ms var(--ease-out),
      margin-top 280ms var(--ease-out);
    will-change: max-height, opacity, transform;
  }

  .topnav.topnav--mobile-ready .topnav__links {
    display: flex;
  }

  .topnav.topnav--menu-open {
    align-items: center;
    row-gap: var(--sp-12);
    padding-bottom: var(--sp-12);
  }

  .topnav.topnav--menu-open .topnav__links {
    max-height: 360px;
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0) scale(1);
    padding: var(--sp-8);
    border: 1px solid var(--border-default);
    background: rgba(255, 255, 255, 0.03);
    margin-top: var(--sp-2);
  }

  .topnav__links .nav-link {
    opacity: 0;
    transform: translateY(-7px);
    transition:
      opacity 240ms var(--ease-out),
      transform 340ms var(--ease-out),
      color var(--duration-micro) var(--ease-standard),
      border-color var(--duration-micro) var(--ease-standard),
      background-color var(--duration-micro) var(--ease-standard);
  }

  .topnav.topnav--menu-open .topnav__links .nav-link {
    opacity: 1;
    transform: translateY(0);
  }

  .topnav.topnav--menu-open .topnav__links .nav-link:nth-child(1) { transition-delay: 35ms; }
  .topnav.topnav--menu-open .topnav__links .nav-link:nth-child(2) { transition-delay: 70ms; }
  .topnav.topnav--menu-open .topnav__links .nav-link:nth-child(3) { transition-delay: 105ms; }
  .topnav.topnav--menu-open .topnav__links .nav-link:nth-child(4) { transition-delay: 140ms; }
  .topnav.topnav--menu-open .topnav__links .nav-link:nth-child(5) { transition-delay: 175ms; }

  .topnav.topnav--menu-open .nav-link {
    display: flex;
    width: 100%;
    text-align: left;
    font-size: var(--text-sm);
    min-height: 42px;
    padding: 9px var(--sp-12);
    border-radius: 12px;
  }

  .topnav__divider {
    display: none;
  }

  .topnav__actions {
    grid-area: actions;
    justify-self: end;
    align-self: center;
    width: auto;
    min-height: 40px;
    margin-left: 0;
    justify-content: flex-end;
    flex-wrap: nowrap;
    gap: var(--sp-8);
    z-index: 2;
  }

  .kbd-hint {
    display: none;
  }

  .topnav__status-label {
    display: none;
  }

  .topnav__status {
    display: none;
  }

  .topnav__toggle {
    display: inline-flex;
    width: 40px;
    height: 40px;
  }

  .side-sheet {
    width: 100vw;
    border-left: none;
  }

  .side-sheet__header,
  .side-sheet__body {
    padding: var(--sp-16);
  }

  .side-sheet__footer {
    padding: var(--sp-12) var(--sp-16) calc(var(--sp-12) + var(--safe-bottom));
  }

  .command-palette-overlay {
    padding-top: min(14vh, 84px);
  }

  .command-palette__input-wrap {
    padding: var(--sp-12) var(--sp-16);
  }

  .command-palette__hint {
    padding: var(--sp-12) var(--sp-16);
    gap: var(--sp-12);
    flex-wrap: wrap;
  }
}

@media (max-width: 640px) {
  :root {
    --page-gutter: var(--sp-12);
  }

  .topnav {
    min-height: 60px;
    padding: calc(var(--sp-8) + var(--safe-top)) calc(var(--page-gutter) + var(--safe-right)) var(--sp-8) calc(var(--page-gutter) + var(--safe-left));
  }

  .topnav__brand {
    max-width: min(72vw, 300px);
    font-size: clamp(0.84rem, 3.7vw, 0.94rem);
  }

  .topnav__brand-accent,
  .kbd-hint span {
    display: none;
  }

  .topnav__status {
    margin-left: 0;
  }

  .topnav.topnav--menu-open {
    row-gap: var(--sp-8);
  }

  .nav-link {
    padding: 6px var(--sp-8);
  }

  .topnav.topnav--menu-open .nav-link {
    min-height: 40px;
  }

  .command-palette {
    width: calc(100vw - 20px);
  }

  .command-palette__hint {
    display: none;
  }

  .modal {
    width: calc(100vw - 20px);
    max-height: 86dvh;
  }

  .modal__header,
  .modal__body,
  .modal__footer {
    padding-left: var(--sp-16);
    padding-right: var(--sp-16);
  }
}