body {
  display: flex;
  flex-direction: column;
}

#app {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.page {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

/* ── Nav ── */

#nav {
  padding: var(--s3) calc(var(--s4) * 1.5);
  border-bottom: 1px solid var(--f2-border);
  display: flex;
  align-items: center;
  gap: calc(var(--s4) * 2);
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  gap: var(--s4);
}

.nav-link {
  color: var(--f3-border);
  text-decoration: none;
  padding: var(--s1) var(--s2);
}

.nav-link:hover { color: var(--text); }
.nav-link.active { color: var(--text); border-bottom: 2px solid var(--primary); }

/* ── Dashboard ── */

.dashboard {
  padding: calc(var(--s4) * 2);
  overflow-y: auto;
}

.dashboard section {
  margin-bottom: calc(var(--s4) * 2);
}

.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--s4);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: var(--s4);
}

.card {
  background: var(--f3-bg);
  border: 1px solid var(--f3-border);
  padding: var(--s4);
  display: flex;
  flex-direction: column;
  gap: var(--s2);
}

.card.clickable { cursor: pointer; }
.card.clickable:hover { border-color: var(--primary); }

.card-icon { font-size: 2em; }
.card-title { font-weight: bold; }
.card-sub { color: var(--f3-border); }

.card.placeholder {
  border-style: dashed;
  color: var(--f2-border);
}

/* ── Session Page ── */

.session-page {
  display: flex;
  flex-direction: column;
}

.session-header {
  padding: var(--s3) calc(var(--s4) * 1.5);
  border-bottom: 1px solid var(--f2-border);
  display: flex;
  align-items: center;
  gap: var(--s4);
  flex-shrink: 0;
}

.back-btn {
  background: none;
  border: none;
  padding: var(--s1) var(--s2);
}

.editable-title {
  cursor: pointer;
}

.editable-title:hover {
  text-decoration: underline;
  text-decoration-style: dotted;
}

/* ── Placeholder Pages ── */

.placeholder-page {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--s4);
  color: var(--f3-border);
}

.placeholder-icon {
  font-size: 4em;
}