.site-header { position: sticky; z-index: 20; top: 0; background: rgb(255 255 255 / .96); border-bottom: 1px solid var(--color-line); backdrop-filter: blur(14px); }
.header-inner { width: min(100% - 2rem, var(--content-wide)); min-height: 78px; margin-inline: auto; display: flex; align-items: center; justify-content: space-between; gap: var(--space-6); }
.brand { display: flex; align-items: center; gap: .75rem; color: var(--color-brand); text-decoration: none; }
.brand-mark { width: 42px; aspect-ratio: 1; display: grid; place-items: center; background: var(--color-brand); color: white; border-radius: 50% 50% 50% 12%; font: 900 .8rem/1 var(--font-ui); letter-spacing: .05em; transform: rotate(-4deg); }
.brand strong, .brand small { display: block; }
.brand strong { font-size: 1.2rem; line-height: 1.1; }
.brand small { margin-top: .25rem; color: var(--color-muted); font-size: .68rem; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; }
.primary-nav { display: flex; align-items: center; gap: .25rem; }
.primary-nav button { min-height: 44px; padding: .6rem .8rem; border: 0; border-radius: var(--radius-md); background: transparent; color: var(--color-brand); font-size: var(--fs-sm); font-weight: 800; cursor: pointer; transition: background var(--transition-fast), color var(--transition-fast), transform var(--transition-fast); }
.primary-nav button span { margin-right: .35rem; font-size: 1rem; }
.primary-nav button:hover { background: var(--color-brand-light); }
.primary-nav button[aria-selected="true"] { background: var(--color-brand); color: white; box-shadow: var(--shadow-sm); }
#app { min-height: calc(100svh - 79px); }
.presentation-exit-floating {
  display: none;
}

body.presentation-mode .site-header,
body.presentation-mode #site-broadcast-banner,
body.presentation-mode .app-status {
  display: none !important;
}

body.presentation-mode #app {
  min-height: 100svh;
  padding-top: 0;
  margin-top: 0;
}

/* Fullscreen F11 media query support for lesson view */
@media (display-mode: fullscreen) {
  body.view-lesson .site-header,
  body[data-current-view="lesson"] .site-header,
  body.presentation-mode .site-header {
    display: none !important;
  }
  body.view-lesson #site-broadcast-banner,
  body[data-current-view="lesson"] #site-broadcast-banner,
  body.presentation-mode #site-broadcast-banner {
    display: none !important;
  }
  body.view-lesson .app-status,
  body[data-current-view="lesson"] .app-status,
  body.presentation-mode .app-status {
    display: none !important;
  }
  body.view-lesson #app,
  body[data-current-view="lesson"] #app,
  body.presentation-mode #app {
    min-height: 100svh;
    padding-top: 0;
    margin-top: 0;
  }
  body.view-lesson .lesson-sidebar,
  body[data-current-view="lesson"] .lesson-sidebar {
    top: 0;
    height: 100svh;
  }
}

body.presentation-mode .presentation-exit-floating {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  position: fixed;
  top: 1rem;
  right: 1rem;
  z-index: 1000;
  padding: 0.55rem 1.15rem;
  font: 700 0.88rem/1 var(--font-ui, system-ui, -apple-system, sans-serif);
  background: var(--color-brand);
  color: #ffffff;
  border: 1.5px solid rgba(255, 255, 255, 0.45);
  border-radius: 9999px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.28);
  cursor: pointer;
  user-select: none;
  transition: background-color 0.15s ease, transform 0.15s ease;
}

body.presentation-mode .presentation-exit-floating:hover {
  background: var(--color-accent);
  border-color: #ffffff;
  transform: translateY(-1px);
}

/* Editorial Content Layout Elements */
.view-kicker {
  color: var(--color-accent);
  font: 800 var(--fs-xs)/1.2 var(--font-ui);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin: 0 0 var(--space-2) 0;
}

#view-title {
  margin: 0 0 var(--space-6) 0;
  color: var(--color-brand);
  font-family: var(--font-ui);
  font-size: clamp(var(--fs-2xl), 5vw, var(--fs-4xl));
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  scroll-margin-top: 8rem;
}

/* Dashboard Premium Open Generative UI Panel Styling */
.dashboard {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-block: clamp(1rem, 2vw, 2.5rem);
  display: grid;
  gap: var(--space-8);
}

.dashboard-hero {
  background: linear-gradient(135deg, var(--color-brand-deep) 0%, var(--color-brand) 65%, #252e37 100%);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-xl);
  padding: clamp(2rem, 4vw, 3.5rem);
  box-shadow: var(--shadow-xl);
  position: relative;
  overflow: hidden;
  color: #ffffff;
}

.dashboard-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 85% 15%, rgba(184, 74, 57, 0.18) 0%, transparent 60%),
              radial-gradient(circle at 10% 90%, rgba(217, 130, 43, 0.12) 0%, transparent 50%);
  pointer-events: none;
}

.dashboard-hero::after {
  content: "";
  position: absolute;
  top: -40px;
  right: -40px;
  width: 220px;
  height: 220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
  opacity: 0.8;
  pointer-events: none;
}

.dashboard-hero .view-kicker {
  color: var(--color-gold);
  font-weight: 850;
  letter-spacing: 0.18em;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.3rem 0.75rem;
  background: rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-full);
  border: 1px solid rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(8px);
}

.dashboard-hero #view-title {
  color: #ffffff;
  margin-top: var(--space-3);
  margin-bottom: var(--space-3);
  font-size: clamp(2.2rem, 5vw, 4rem);
  font-weight: 900;
  letter-spacing: -0.04em;
  line-height: 1.05;
}

.hero-desc {
  font-family: var(--font-ui);
  font-size: var(--fs-lg);
  line-height: 1.65;
  color: rgba(255, 255, 255, 0.92);
  margin: var(--space-4) 0 0 0;
  max-width: var(--content-reading);
}

.dashboard-section-title {
  font: 850 var(--fs-xl)/1.2 var(--font-ui);
  color: var(--color-brand);
  margin-top: var(--space-4);
  margin-bottom: var(--space-2);
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.dashboard-section-title::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 1.2em;
  background: var(--color-accent);
  border-radius: var(--radius-full);
}

/* Stat Grid & Generative Cards */
.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
  gap: var(--space-4);
}

.stat-card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: var(--space-5) var(--space-6);
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), border-color var(--transition-fast);
}

.stat-card::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at top right, rgba(28, 34, 40, 0.04) 0%, transparent 60%);
  pointer-events: none;
}

.stat-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: rgba(28, 34, 40, 0.2);
}

.stat-card strong {
  display: block;
  font-family: var(--font-ui);
  font-size: var(--fs-3xl);
  font-weight: 850;
  line-height: 1.1;
  color: var(--color-brand);
  margin-bottom: var(--space-1);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.03em;
}

.stat-card span {
  display: block;
  font: 750 var(--fs-xs)/1.2 var(--font-ui);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-muted);
  margin-bottom: var(--space-3);
}

.stat-detail {
  font-family: var(--font-ui);
  font-size: var(--fs-xs);
  line-height: 1.45;
  color: var(--color-muted);
  margin: 0;
}

/* Colored accent borders based on status */
.stat-card[data-stat="answered"] {
  border-top: 4px solid var(--color-brand);
}

.stat-card[data-stat="correct"] {
  border-top: 4px solid var(--color-success);
}

.stat-card[data-stat="wrong"] {
  border-top: 4px solid var(--color-accent);
}

.stat-card[data-stat="total"] {
  border-top: 4px solid var(--color-gold);
}

/* Dashboard Guide steps */
.dashboard-guide {
  background-color: var(--color-surface);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-xl);
  padding: var(--space-6) var(--space-8);
  box-shadow: var(--shadow-sm);
}

.dashboard-guide h3 {
  font: 800 var(--fs-base)/1.2 var(--font-ui);
  color: var(--color-brand);
  margin: 0 0 var(--space-4) 0;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.guide-steps {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(18rem, 1fr));
  gap: var(--space-4);
}

.guide-steps li {
  font-family: var(--font-ui);
  font-size: var(--fs-sm);
  line-height: 1.6;
  color: var(--color-ink);
  padding: var(--space-5);
  background-color: var(--color-canvas);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-line);
  border-left: 4px solid var(--color-brand);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.guide-steps li:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
  background-color: var(--color-surface);
}

.guide-steps li strong {
  display: block;
  font-size: var(--fs-base);
  color: var(--color-brand);
  margin-bottom: var(--space-2);
}

/* Dashboard Action Buttons */
.dashboard-actions {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
  margin-top: var(--space-2);
}

.dashboard-actions button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: var(--space-3) var(--space-6);
  font-family: var(--font-ui);
  font-weight: 750;
  font-size: var(--fs-sm);
  border-radius: var(--radius-md);
  min-width: 12rem;
  min-height: 48px;
  cursor: pointer;
  transition: transform var(--transition-fast), background-color var(--transition-fast), border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.btn-primary {
  background-color: var(--color-brand);
  color: var(--color-surface);
  border: 1px solid var(--color-brand);
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background-color: var(--color-brand-hover);
  border-color: var(--color-brand-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background-color: var(--color-brand-light);
  color: var(--color-brand);
  border: 1px solid rgba(28, 34, 40, 0.15);
}

.btn-secondary:hover {
  background-color: var(--color-surface);
  transform: translateY(-2px);
  border-color: var(--color-brand);
  box-shadow: var(--shadow-sm);
}

.storage-note {
  margin: var(--space-4) 0 0 0;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  background-color: var(--color-warning-light);
  border: 1px solid var(--color-warning);
  color: var(--color-warning);
  font-family: var(--font-ui);
  font-size: var(--fs-sm);
  font-weight: 600;
}

.empty-view { width: min(100% - 2rem, 58rem); margin-inline: auto; padding-block: 6rem; }
.empty-view h1 { color: var(--color-brand); font-size: var(--fs-2xl); }
@keyframes rise-in { from { opacity: 0; transform: translateY(24px); } to { opacity: 1; transform: none; } }

@media (max-width: 980px) {
  .header-inner { align-items: flex-start; padding-block: .85rem; }
  .brand small { display: none; }
  .primary-nav { overflow-x: auto; max-width: 72vw; }
  .primary-nav button { white-space: nowrap; }
}
@media (max-width: 760px) {
  .site-header { position: relative; }
  .header-inner { width: 100%; min-height: auto; padding: .8rem 1rem 0; display: block; }
  .brand { padding-bottom: .75rem; }
  .brand-mark { width: 36px; }
  .primary-nav { max-width: none; margin-inline: -1rem; padding: 0 1rem .75rem; }
  .primary-nav button { padding: .55rem .7rem; }
  .primary-nav button span { display: none; }
  #app { min-height: auto; }
}

@media (prefers-reduced-motion: reduce) { .dashboard-hero { animation: none; } }