.app-shell { min-height: 100vh; }

.sidebar {
  position: fixed;
  inset: 0 auto 0 0;
  z-index: 30;
  display: flex;
  width: var(--sidebar-width);
  flex-direction: column;
  border-right: 1px solid var(--border-subtle);
  background: var(--bg-sidebar);
  padding: var(--space-32) var(--space-16) var(--space-24);
}

.brand {
  display: inline-flex;
  align-items: center;
  height: 2.5rem;
  padding: 0 var(--space-12);
  font-size: var(--text-lg);
  font-weight: 700;
  letter-spacing: 0.13em;
}

.brand-mark {
  width: 1.75rem;
  height: 1.75rem;
  margin-right: var(--space-12);
  object-fit: contain;
}
.topbar-brand { display: none; align-items: center; font-size: var(--text-md); font-weight: 700; letter-spacing: .13em; }
.topbar-brand.visible { display: inline-flex; }

.sidebar-nav { margin-top: var(--space-48); }
.sidebar-admin { overflow-y: auto; border-top: 1px solid var(--border-subtle); margin-top: var(--space-24); padding-top: var(--space-16); }
.sidebar-admin-label { margin: 0 var(--space-12) var(--space-8); color: var(--text-muted); font-size: .6875rem; font-weight: 600; letter-spacing: .08em; text-transform: uppercase; }
.sidebar-bottom { margin-top: auto; }
.nav-list { display: grid; gap: var(--space-4); margin: 0; padding: 0; list-style: none; }
.nav-link {
  display: flex;
  width: 100%;
  align-items: center;
  min-height: 2.75rem;
  gap: var(--space-12);
  border: 1px solid transparent;
  border-radius: var(--radius);
  background: transparent;
  padding: var(--space-8) var(--space-12);
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: 500;
  text-align: left;
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}
.nav-link svg { width: 1.125rem; height: 1.125rem; stroke-width: 1.7; }
.nav-link:hover { background: var(--bg-surface); color: var(--text-primary); }
.nav-link.active {
  border-color: var(--border-default);
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-weight: 600;
}

.app-body { min-height: 100vh; margin-left: var(--sidebar-width); }
.app-body.guest-app-body { margin-left: 0; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  height: var(--topbar-height);
  align-items: center;
  justify-content: space-between;
  gap: var(--space-24);
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-page);
  padding: var(--space-16) var(--space-32);
}

.global-search { position: relative; width: min(35rem, 58%); }
.search-field {
  width: 100%;
  height: 2.75rem;
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  background: var(--bg-surface);
  color: var(--text-primary);
  padding: 0 var(--space-16) 0 var(--space-48);
  transition: border-color var(--transition), background var(--transition);
}
.search-field:hover { background: var(--bg-surface-hover); }
.search-field:focus { border-color: var(--border-strong); outline: 2px solid var(--text-primary); outline-offset: 2px; }
.search-field::placeholder { color: var(--text-muted); }
.search-icon { position: absolute; left: var(--space-16); top: 0.8rem; width: 1.125rem; color: var(--text-muted); pointer-events: none; }

.search-results {
  position: absolute;
  top: calc(100% + var(--space-8));
  left: 0;
  right: 0;
  z-index: 50;
  max-height: min(32rem, 70vh);
  overflow-y: auto;
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  background: var(--bg-elevated);
  box-shadow: 0 1rem 2.5rem rgba(0, 0, 0, 0.4);
}
.search-results[hidden] { display: none; }
.search-results-title { padding: var(--space-16) var(--space-16) var(--space-8); color: var(--text-muted); font-size: var(--text-xs); font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; }
.search-result { display: grid; grid-template-columns: 2.5rem 1fr; gap: var(--space-12); align-items: center; padding: var(--space-12) var(--space-16); border-top: 1px solid var(--border-subtle); }
.search-result:hover, .search-result[aria-selected='true'] { background: var(--bg-surface-hover); }
.search-result .book-cover-wrap { width: 2.5rem; aspect-ratio: 2 / 3; background: var(--border-default); }
.search-result > span:not(.book-cover-wrap), .search-result > span:not(.book-cover-wrap) span, .search-result strong { display: block; }
.search-result > span:not(.book-cover-wrap) span { color: var(--text-secondary); font-size: var(--text-sm); }

.topbar-actions { display: flex; align-items: center; gap: var(--space-12); margin-left: auto; }
.notifications { position: relative; }
.notification-button { position: relative; display: grid; width: 2.75rem; height: 2.75rem; place-items: center; border: 1px solid transparent; border-radius: var(--radius); background: transparent; color: var(--text-secondary); cursor: pointer; }
.notification-button:hover, .notification-button[aria-expanded='true'] { border-color: var(--border-default); background: var(--bg-surface); color: var(--text-primary); }
.notification-badge { position: absolute; top: .15rem; right: .15rem; display: grid; min-width: 1.1rem; height: 1.1rem; place-items: center; border: 2px solid var(--bg-page); border-radius: 999px; background: var(--text-primary); padding-inline: .2rem; color: var(--bg-page); font-size: .625rem; font-weight: 700; }
.notification-badge[hidden] { display: none; }
.notification-panel { position: absolute; top: calc(100% + var(--space-8)); right: 0; z-index: 60; width: min(26rem, calc(100vw - 2rem)); max-height: min(38rem, calc(100vh - 6rem)); overflow: hidden auto; border: 1px solid var(--border-default); border-radius: var(--radius); background: var(--bg-elevated); box-shadow: 0 1rem 2.5rem rgba(0,0,0,.5); }
.notification-panel[hidden] { display: none; }
.notification-panel > header { position: sticky; top: 0; z-index: 1; display: flex; align-items: center; justify-content: space-between; gap: var(--space-16); border-bottom: 1px solid var(--border-default); background: var(--bg-elevated); padding: var(--space-16); }
.notification-panel h2 { font-size: var(--text-lg); }
.notification-list > .empty-state { border-top: 0; padding: var(--space-32) var(--space-24); }
.notification-list > .empty-state p { margin-bottom: 0; }
.notification-item { display: grid; width: 100%; grid-template-columns: 2.5rem minmax(0,1fr); gap: var(--space-12); align-items: center; border-bottom: 1px solid var(--border-subtle); background: transparent; padding: var(--space-16); color: var(--text-secondary); text-align: left; cursor: pointer; }
.notification-item.is-unread { background: var(--bg-surface); color: var(--text-primary); }
.notification-item:hover { background: var(--bg-surface-hover); }
.notification-item img, .notification-item-icon { display: grid; width: 2.5rem; height: 2.5rem; place-items: center; border: 1px solid var(--border-default); border-radius: 50%; object-fit: cover; }
.notification-item strong, .notification-item small { display: block; }
.notification-item strong { font-size: var(--text-sm); line-height: 1.45; }
.notification-item small { margin-top: var(--space-4); color: var(--text-muted); }
.notification-more { padding: var(--space-12); text-align: center; }
.account { position: relative; }
.guest-account { margin-left: auto; }
.guest-signup { display: flex; align-items: center; }
.account-button {
  display: flex;
  min-width: 11rem;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-12);
  border-radius: var(--radius);
  background: transparent;
  padding: var(--space-4);
  cursor: pointer;
}
.account-button:hover { background: var(--bg-surface); }
.account-copy { text-align: right; }
.account-copy strong, .account-copy span { display: block; }
.account-copy strong { font-size: var(--text-sm); }
.account-copy span { color: var(--text-muted); font-size: var(--text-xs); }
.avatar { width: 2.5rem; height: 2.5rem; border: 1px solid var(--border-default); border-radius: 50%; object-fit: cover; }
.account-menu {
  position: absolute;
  top: calc(100% + var(--space-8));
  right: 0;
  z-index: 50;
  width: 13rem;
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  background: var(--bg-elevated);
  padding: var(--space-8);
  box-shadow: 0 1rem 2.5rem rgba(0, 0, 0, 0.4);
}
.account-menu[hidden] { display: none; }
.menu-link { display: flex; width: 100%; min-height: 2.5rem; align-items: center; border-radius: var(--radius-sm); background: transparent; padding: var(--space-8) var(--space-12); color: var(--text-secondary); cursor: pointer; }
.menu-link:hover { background: var(--bg-surface-hover); color: var(--text-primary); }

.page {
  width: 100%;
  padding: var(--space-32);
}
.page > section + section { margin-top: var(--space-48); }

.page-header {
  display: flex;
  min-height: 3.5rem;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-24);
  margin-bottom: var(--space-24);
}
.page-header p { margin-top: var(--space-8); color: var(--text-secondary); }

.section-header { display: flex; align-items: baseline; justify-content: space-between; gap: var(--space-16); margin-bottom: var(--space-24); }
.section-header .text-link { flex: 0 0 auto; }

.grid-12 { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: var(--space-24); align-items: start; }
.span-12 { grid-column: span 12; }
.span-7 { grid-column: span 7; }
.span-5 { grid-column: span 5; }
.span-8 { grid-column: span 8; }
.span-4 { grid-column: span 4; }

.mobile-nav { display: none; }