/* ═══════════════════════════════════════════════════════════
   APP SHELL LAYOUT — Sidebar + Topbar + Main
═══════════════════════════════════════════════════════════ */

#app {
  display: grid;
  grid-template-columns: 248px 1fr;
  grid-template-rows: auto 1fr;
  min-height: 100vh;
}

body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
}

/* ═══════════════════════════════════════════════════════════
   SIDEBAR
═══════════════════════════════════════════════════════════ */

.sidebar {
  grid-column: 1;
  grid-row: 1 / -1;
  border-right: 1px solid var(--line-soft);
  background: linear-gradient(180deg, var(--bg-1) 0%, var(--bg-0) 100%);
  padding: 22px 16px 16px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  z-index: 100;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 8px 14px;
  border-bottom: 1px dashed var(--line);
}

.brand-mark {
  width: 32px;
  height: 32px;
  border-radius: 10px;
  flex-shrink: 0;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-h) 100%);
  display: grid;
  place-items: center;
  color: var(--accent-ink);
  font-weight: 700;
  font-family: 'Fraunces', serif;
  font-style: italic;
  box-shadow: 0 6px 18px -6px var(--accent-glow);
}

.brand-name {
  font-family: 'Fraunces', serif;
  font-weight: 500;
  font-size: 17px;
  letter-spacing: -0.01em;
}

.brand-name em {
  font-style: italic;
  color: var(--accent);
  font-weight: 400;
}

.nav-group-label {
  font-family: 'Geist Mono', monospace;
  font-size: 10px;
  letter-spacing: 0.22em;
  color: var(--text-mute);
  text-transform: uppercase;
  padding: 0 10px 6px;
}

.nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.nav a {
  display: flex;
  align-items: center;
  gap: 11px;
  padding: 9px 11px;
  border-radius: 9px;
  color: var(--text-dim);
  text-decoration: none;
  font-weight: 500;
  border: 1px solid transparent;
  transition:
    background-color var(--transition-colors),
    color var(--transition-colors),
    border-color var(--transition-colors);
}

.nav a svg {
  width: 16px;
  height: 16px;
  opacity: 0.85;
  flex-shrink: 0;
}

.nav a:hover {
  background: var(--bg-2);
  color: var(--text);
}

.nav a.active {
  background: var(--bg-2);
  color: var(--text);
  border-color: var(--line);
  box-shadow: inset 2px 0 0 var(--accent);
}

.nav a .count {
  margin-left: auto;
  font-family: 'Geist Mono', monospace;
  font-size: 11px;
  color: var(--text-mute);
  background: var(--bg-3);
  padding: 1px 6px;
  border-radius: 6px;
}

.sidebar-footer {
  margin-top: auto;
  border-top: 1px dashed var(--line);
  padding-top: 14px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.user {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 4px;
}

.avatar {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  flex-shrink: 0;
  background: linear-gradient(135deg, #3a4cff, #7aa2ff);
  display: grid;
  place-items: center;
  color: #fff;
  font-weight: 600;
  font-size: 13px;
}

.user-info {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.user-info strong {
  font-weight: 600;
  font-size: 13px;
}

.user-info span {
  font-size: 11px;
  color: var(--text-mute);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.logout {
  text-align: left;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text-dim);
  padding: 8px 11px;
  border-radius: 9px;
  font-family: 'Geist', sans-serif;
  font-size: 12px;
  cursor: pointer;
  transition:
    background-color var(--transition-colors),
    color var(--transition-colors),
    border-color var(--transition-colors);
}

.logout:hover {
  background: var(--bg-2);
  color: var(--text);
  border-color: var(--logout-hover-bd);
}

/* ═══════════════════════════════════════════════════════════
   TOPBAR
═══════════════════════════════════════════════════════════ */

.topbar {
  grid-row: 1;
  grid-column: 2;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 32px;
  border-bottom: 1px solid var(--line-soft);
  background: var(--topbar-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 10;
}

.breadcrumb {
  min-width: 100px;
}

.breadcrumb {
  font-family: 'Geist Mono', monospace;
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--text-mute);
  text-transform: uppercase;
}

.breadcrumb span {
  color: var(--text-dim);
}

.topbar .spacer {
  flex: 1;
}

.hamburger-btn {
  display: none; /* Hidden on desktop, shown on mobile via @media */
}

.iconbtn {
  width: 34px;
  height: 34px;
  border-radius: 9px;
  border: 1px solid var(--line);
  background: var(--bg-2);
  color: var(--text-dim);
  display: grid;
  place-items: center;
  cursor: pointer;
  transition:
    background-color var(--transition-colors),
    color var(--transition-colors),
    border-color var(--transition-colors);
  flex-shrink: 0;
}

.iconbtn:hover {
  color: var(--accent);
  border-color: var(--hover-bd);
}

.iconbtn svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

.icon-sun {
  display: var(--show-sun);
}

.icon-moon {
  display: var(--show-moon);
}

/* ═══════════════════════════════════════════════════════════
   PAGE CONTENT
═══════════════════════════════════════════════════════════ */

.main {
  grid-row: 1 / -1;
  grid-column: 2;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

#page-content {
  flex: 1;
  overflow-y: auto;
  padding: 24px 32px 32px;
  max-width: 1600px;
  width: 100%;
  margin: 0 auto;
}

/* ═══════════════════════════════════════════════════════════
   RESPONSIVE — Tablet/Mobile Breakpoint (≤ 879px)
═══════════════════════════════════════════════════════════ */

@media (max-width: 879px) {
  .app {
    grid-template-columns: 1fr;
  }

  /* Sidebar becomes fixed overlay on mobile */
  .sidebar {
    position: fixed;
    left: -248px;
    top: 0;
    height: 100vh;
    width: 248px;
    z-index: 200;
    transition: left var(--transition-motion);
    border-right: 1px solid var(--line-soft);
  }

  .sidebar.open {
    left: 0;
  }

  /* Overlay behind sidebar */
  .sidebar.open::before {
    content: '';
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.2);
    z-index: -1;
    pointer-events: auto;
  }

  /* Show hamburger button */
  .hamburger-btn {
    display: flex !important;
  }

  .topbar {
    padding: 12px 16px;
    gap: 12px;
  }

  .breadcrumb {
    min-width: 0;
    flex: 1;
  }
}

@media (max-width: 639px) {
  .topbar {
    padding: 10px 12px;
    gap: 8px;
  }

  #page-content {
    padding: 16px 16px 20px;
  }

  .hamburger-btn {
    min-width: var(--touch-min);
    min-height: var(--touch-min);
  }
}