.app-frame {
  display: grid;
  grid-template-columns: 248px minmax(0, 1fr);
  gap: var(--space-5);
  width: min(var(--content-max), 100%);
  min-height: 100vh;
  margin: 0 auto;
  padding: var(--space-5);
}

.app-workspace {
  min-width: 0;
}

.sidebar {
  position: sticky;
  top: var(--space-5);
  align-self: start;
  display: grid;
  gap: var(--space-4);
  max-height: calc(100vh - 2.5rem);
  overflow: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: color-mix(in srgb, var(--color-card) 94%, transparent);
  box-shadow: var(--shadow-card);
  padding: var(--space-3);
}

.sidebar-brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  min-height: 3.2rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-heading);
  font-weight: 750;
  letter-spacing: -0.02em;
  padding: 0.25rem 0.35rem 0.8rem;
  text-decoration: none;
}

.brand-stack {
  line-height: 1.15;
}

.brand-mark {
  display: grid;
  width: 2.25rem;
  height: 2.25rem;
  place-items: center;
  border: 1px solid color-mix(in srgb, var(--color-primary) 24%, var(--color-border));
  border-radius: 11px;
  background: var(--color-primary-soft);
  color: var(--color-primary-dark);
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 800;
}

.brand-text {
  padding-right: 0.5rem;
}

.side-nav {
  display: grid;
  gap: 0.12rem;
}

.nav-link {
  display: grid;
  grid-template-columns: 2rem minmax(0, 1fr);
  align-items: center;
  gap: 0.65rem;
  min-height: 2.55rem;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  color: var(--color-muted);
  font-size: 0.94rem;
  font-weight: 650;
  padding: 0.48rem 0.65rem;
  text-decoration: none;
  transition: background 150ms ease, border-color 150ms ease, color 150ms ease;
}

.nav-index {
  display: grid;
  width: 1.65rem;
  height: 1.65rem;
  place-items: center;
  border-radius: 8px;
  background: var(--color-surface-muted);
  color: var(--color-subtle);
  font-size: 0.68rem;
  font-weight: 800;
  letter-spacing: 0.04em;
}

.nav-link:hover {
  background: var(--color-surface-muted);
  color: var(--color-heading);
}

.nav-link.is-active {
  border-color: color-mix(in srgb, var(--color-primary) 24%, var(--color-border));
  background: var(--color-primary-soft);
  color: var(--color-primary-dark);
}

.nav-link.is-active .nav-index {
  background: var(--color-card-solid);
  color: var(--color-primary-dark);
}

.topbar {
  position: sticky;
  top: var(--space-5);
  z-index: 20;
  display: grid;
  grid-template-columns: minmax(180px, 1fr) auto;
  align-items: center;
  gap: var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: color-mix(in srgb, var(--color-card) 96%, transparent);
  box-shadow: var(--shadow-tight);
  padding: 0.68rem 0.75rem 0.68rem 1rem;
}

.topbar-title {
  min-width: 0;
}

.topbar-title strong {
  display: block;
  overflow: hidden;
  color: var(--color-heading);
  font-size: 1rem;
  font-weight: 720;
  letter-spacing: -0.01em;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.topbar-title .eyebrow {
  margin-bottom: 0.25rem;
}

.topbar-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 0.5rem;
}

.main {
  padding: var(--space-5) 0 var(--space-8);
}

.page-stack {
  display: grid;
  gap: var(--space-5);
}

.hero,
.dashboard-hero {
  display: grid;
  gap: var(--space-5);
  align-items: stretch;
}

.hero {
  grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.9fr);
}

.dashboard-hero {
  grid-template-columns: minmax(0, 1.35fr) minmax(300px, 0.8fr);
}

.hero-copy,
.hero-card,
.dashboard-hero > *,
.page-header,
.panel,
.question-card,
.pack-card,
.empty-state {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: var(--color-card);
  box-shadow: var(--shadow-card);
}

.hero-copy,
.hero-card,
.dashboard-hero > *,
.page-header,
.panel,
.question-card,
.empty-state {
  padding: clamp(1.2rem, 3vw, 2rem);
}

.dashboard-hero > :first-child,
.page-header {
  background:
    linear-gradient(135deg, color-mix(in srgb, var(--color-card) 96%, white) 0%, var(--color-card) 55%, var(--color-primary-soft) 190%);
}

.hero-copy {
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.hero-card {
  align-self: stretch;
  position: relative;
  overflow: hidden;
}

.hero-card::after {
  content: none;
}

.study-plan-card {
  display: grid;
  align-content: start;
  gap: 0.85rem;
}

.dashboard-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.55fr) minmax(260px, 0.65fr);
  gap: var(--space-5);
}

.quick-actions-panel .mode-grid {
  grid-template-columns: repeat(4, minmax(140px, 1fr));
}

.privacy-note {
  align-content: start;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2,
h3 {
  color: var(--color-heading);
  letter-spacing: -0.025em;
}

h1 {
  max-width: 13ch;
  margin-bottom: 0.8rem;
  font-family: var(--font-display);
  font-size: clamp(2rem, 3.9vw, 3.15rem);
  font-weight: 760;
  line-height: 1.04;
}

h2 {
  margin-bottom: 0.55rem;
  font-family: var(--font-body);
  font-size: clamp(1.2rem, 2.1vw, 1.55rem);
  font-weight: 740;
  line-height: 1.18;
}

h3 {
  margin-bottom: 0.4rem;
  font-size: 1.05rem;
  font-weight: 720;
  line-height: 1.25;
}

p {
  max-width: 72ch;
  margin-bottom: 0.75rem;
  color: var(--color-muted);
  line-height: 1.65;
}

.hero-subtitle {
  max-width: 48ch;
  color: var(--color-heading);
  font-size: clamp(1.18rem, 2.2vw, 1.55rem);
  font-weight: 680;
  line-height: 1.35;
}

.content-grid,
.pack-grid,
.stats-grid,
.feature-grid {
  display: grid;
  gap: var(--space-5);
}

.content-grid {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.pack-grid {
  grid-template-columns: repeat(auto-fit, minmax(290px, 1fr));
}

.stats-grid,
.feature-grid {
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
}

.compact-grid {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.mobile-nav {
  display: none;
}

@media (max-width: 1080px) {
  .app-frame {
    grid-template-columns: 220px minmax(0, 1fr);
  }

  .quick-actions-panel .mode-grid {
    grid-template-columns: repeat(2, minmax(150px, 1fr));
  }
}

@media (max-width: 900px) {
  .dashboard-grid,
  .hero,
  .dashboard-hero {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 820px) {
  .app-frame {
    display: block;
    padding: var(--space-3);
    padding-bottom: 5.8rem;
  }

  .sidebar {
    display: none;
  }

  .topbar {
    position: sticky;
    top: 0.5rem;
    grid-template-columns: 1fr;
    align-items: stretch;
    border-radius: var(--radius-lg);
  }

  .topbar-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: stretch;
  }

  .status-pill,
  .pack-select {
    grid-column: 1 / -1;
  }

  .main {
    padding-top: var(--space-4);
  }

  .mobile-nav {
    position: fixed;
    right: 0.75rem;
    bottom: 0.75rem;
    left: 0.75rem;
    z-index: 30;
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 0.25rem;
    border: 1px solid var(--color-border);
    border-radius: 18px;
    background: var(--color-card-solid);
    box-shadow: var(--shadow-soft);
    padding: 0.35rem;
  }

  .mobile-nav .nav-link {
    display: flex;
    justify-content: center;
    min-height: 2.65rem;
    padding: 0.45rem 0.25rem;
    font-size: 0.78rem;
    text-align: center;
  }

  .mobile-nav .nav-index {
    display: none;
  }
}

@media (max-width: 640px) {
  .topbar-actions {
    grid-template-columns: 1fr;
  }

  h1 {
    max-width: none;
  }

  .dashboard-hero > *,
  .page-header,
  .panel,
  .question-card,
  .empty-state {
    padding: 1.05rem;
  }
}