/* ============================================================
   Local English Vocabulary — layout.css
   App shell / sidebar / topbar / view / bottom navigation
   ============================================================ */

.app {
  min-height: 100vh;
}

/* ---------------------------------------------- desktop : sidebar */

.sidebar {
  position: fixed;
  inset: 0 auto 0 0;
  z-index: 40;
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  width: var(--sidebar-w);
  height: 100vh;
  padding: var(--space-4) var(--space-3);
  background: var(--bg-elev);
  border-right: 1px solid var(--border);
}

.sidebar__brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 4px 8px 0;
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 10px;
  background: var(--accent);
  color: var(--on-accent);
  font-size: var(--text-md);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.brand__name {
  font-size: var(--text-md);
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.2;
}

.brand__sub {
  font-size: var(--text-xs);
  color: var(--text-3);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.sidebar__nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
  overflow-y: auto;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  height: 36px;
  padding: 0 10px;
  border-radius: var(--radius-sm);
  color: var(--text-2);
  font-size: var(--text-base);
  font-weight: 500;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}

.nav-item:hover {
  background: var(--surface-2);
  color: var(--text);
}

.nav-item[aria-current="page"] {
  background: var(--accent-soft);
  color: var(--accent);
}

.nav-item__icon {
  display: inline-flex;
}

.sidebar__footer {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-top: auto;
  padding: 0 4px;
}

.sidebar__note {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: var(--text-xs);
  color: var(--text-3);
}

/* ---------------------------------------------- main column */

.app__main {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  margin-left: var(--sidebar-w);
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  gap: var(--space-3);
  height: var(--topbar-h);
  padding: 0 var(--space-8);
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

@supports (backdrop-filter: blur(10px)) {
  .topbar {
    background: color-mix(in srgb, var(--bg) 78%, transparent);
    -webkit-backdrop-filter: blur(14px);
    backdrop-filter: blur(14px);
  }
}

.topbar__titles {
  min-width: 0;
}

.topbar__title {
  font-size: var(--text-md);
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.25;
}

.topbar__subtitle {
  font-size: var(--text-sm);
  color: var(--text-3);
}

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

.view {
  flex: 1;
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: var(--space-6) var(--space-8) var(--space-10);
}

.view:focus {
  outline: none;
}

/* ---------------------------------------------- mobile : bottom nav */

.bottom-nav {
  display: none;
}

@media (max-width: 767px) {
  .sidebar {
    display: none;
  }

  .app__main {
    margin-left: 0;
  }

  .topbar {
    padding: 0 var(--space-4);
  }

  .view {
    padding: var(--space-4) var(--space-4) calc(var(--bottomnav-h) + var(--space-8) + env(safe-area-inset-bottom));
  }

  .bottom-nav {
    position: fixed;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 45;
    display: flex;
    align-items: stretch;
    height: calc(var(--bottomnav-h) + env(safe-area-inset-bottom));
    padding-bottom: env(safe-area-inset-bottom);
    background: var(--bg-elev);
    border-top: 1px solid var(--border);
  }

  .bottom-nav__item {
    display: flex;
    flex: 1 1 0;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 3px;
    min-width: 0;
    padding: 6px 1px;
    color: var(--text-3);
    /* 7 个入口在 360px 下每个只有 ~51px：字号与字距要留出余量 */
    font-size: 9.5px;
    font-weight: 500;
    letter-spacing: 0;
    transition: color var(--dur) var(--ease);
  }

  .bottom-nav__item > span:last-child {
    max-width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .bottom-nav__item[aria-current="page"] {
    color: var(--accent);
  }

  .bottom-nav__icon {
    display: inline-flex;
  }
}

/* ---------------------------------------------- desktop breakpoints */

@media (min-width: 768px) {
  .bottom-nav {
    display: none;
  }
}

@media (min-width: 768px) and (max-width: 1023px) {
  :root {
    --sidebar-w: 212px;
  }

  .view,
  .topbar {
    padding-right: var(--space-6);
    padding-left: var(--space-6);
  }
}

@media (min-width: 1440px) {
  :root {
    --content-max: 1240px;
  }
}

/* ---------------------------------------------- auth layout */

body.auth-layout .sidebar,
body.auth-layout .topbar,
body.auth-layout .bottom-nav {
  display: none;
}

body.auth-layout .app__main {
  margin-left: 0;
}

body.auth-layout .view {
  max-width: none;
  padding: 0;
}