/* Base & Layout Styles adhering to DESIGN.md */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-body);
  background-color: var(--color-surface);
  color: var(--color-on-surface);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Container */
.app-container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--gutter-desktop);
}

@media (max-width: 768px) {
  .app-container {
    padding: 0 var(--gutter-mobile);
  }
}

/* Typography Headings */
h1, h2, h3, h4, .font-headline {
  font-family: var(--font-headline);
  font-weight: 700;
  color: var(--color-on-surface);
  letter-spacing: -0.02em;
}

.font-mono {
  font-family: var(--font-mono);
}

/* Header */
.app-header {
  background: var(--color-surface-lowest);
  border-bottom: 1px solid var(--color-border-subtle);
  padding: var(--space-md) 0;
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: var(--shadow-subtle);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.brand-section {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.brand-logo-link {
  display: flex;
  align-items: center;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
  border-radius: var(--radius-md, 8px);
}

.brand-logo-link:hover {
  transform: scale(1.02);
  opacity: 0.95;
}

[data-theme="dark"] .brand-logo-link {
  background: rgba(255, 255, 255, 0.95);
  padding: 4px 10px;
  border-radius: var(--radius-md, 8px);
  box-shadow: 0 0 16px rgba(96, 165, 250, 0.5), 0 0 32px rgba(59, 130, 246, 0.25);
  border: 1px solid rgba(191, 219, 254, 0.8);
}

[data-theme="dark"] .brand-logo-link:hover {
  background: #ffffff;
  box-shadow: 0 0 22px rgba(96, 165, 250, 0.75), 0 0 45px rgba(59, 130, 246, 0.45);
  transform: scale(1.03);
}

.brand-logo {
  height: 42px;
  width: auto;
  max-width: 160px;
  object-fit: contain;
  display: block;
}

[data-theme="dark"] .brand-logo {
  height: 38px;
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-on-surface);
}

.brand-subtitle {
  font-size: 0.75rem;
  color: var(--color-on-surface-variant);
  font-family: var(--font-mono);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

/* Header Actions & Theme Toggle Switch */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.theme-toggle-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px 5px 8px;
  background: var(--color-surface-container);
  border: 1px solid var(--color-outline-variant);
  border-radius: var(--radius-full);
  color: var(--color-on-surface);
  font-family: var(--font-body);
  font-size: 0.8125rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
}

.theme-toggle-btn:hover {
  background: var(--color-surface-high);
  border-color: var(--color-primary-brand);
  color: var(--color-primary-brand);
}

.theme-toggle-switch {
  width: 36px;
  height: 20px;
  background: var(--color-surface-highest);
  border-radius: var(--radius-full);
  position: relative;
  display: flex;
  align-items: center;
  padding: 2px;
  transition: background 0.2s ease, border-color 0.2s ease;
  border: 1px solid var(--color-outline-variant);
}

.theme-icon {
  position: absolute;
  top: 2px;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.sun-icon {
  left: 3px;
  color: #f59e0b;
  opacity: 1;
}

.moon-icon {
  right: 3px;
  color: #94a3b8;
  opacity: 0.35;
}

[data-theme="dark"] .theme-toggle-switch {
  background: #192238;
  border-color: #3b82f6;
}

[data-theme="dark"] .sun-icon {
  opacity: 0.3;
  color: #64748b;
}

[data-theme="dark"] .moon-icon {
  opacity: 1;
  color: #60a5fa;
}

.theme-mode-text {
  font-family: var(--font-body);
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-on-surface);
}



.stat-chip {
  background: var(--color-surface-tint);
  border: 1px solid rgba(69, 95, 171, 0.2);
  border-radius: var(--radius-base);
  padding: 4px var(--space-sm);
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 0.8125rem;
}

.stat-chip-label {
  color: var(--color-on-surface-variant);
  font-weight: 500;
}

.stat-chip-value {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--color-primary);
}

/* Main Layout Grid */
.main-content {
  flex: 1;
  padding: var(--space-lg) 0 var(--space-3xl);
}

.layout-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-xl);
}

/* Media Selector & Chassis Drive Population Top Row (Side-by-side on desktop) */
.media-population-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-lg);
  align-items: start;
}

@media (min-width: 1024px) {
  .media-population-row {
    grid-template-columns: 1.35fr 1fr;
    gap: var(--space-lg);
    align-items: start;
  }
}

@media (min-width: 1280px) {
  .media-population-row {
    grid-template-columns: 1.4fr 1fr;
    gap: var(--space-xl);
    align-items: start;
  }
}

.media-selector-col,
.population-col {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

/* Section Card */
.card-section {
  background: var(--color-surface-lowest);
  border: 1px solid var(--color-border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  overflow: hidden;
}

.card-header {
  padding: var(--space-md) var(--space-lg);
  background: var(--color-surface-subtle);
  border-bottom: 1px solid var(--color-border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.card-title-group {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.card-title {
  font-size: 1.125rem;
  font-weight: 700;
}

.card-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: var(--radius-base);
  background: var(--color-surface-tint);
  color: var(--color-primary);
  border: 1px solid rgba(69, 95, 171, 0.2);
}

.card-body {
  padding: var(--space-lg);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  padding: var(--space-xs) var(--space-md);
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius-base);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.15s ease;
  line-height: 1.25;
}

.btn-primary {
  background: var(--color-primary-brand);
  color: #ffffff;
  border-color: rgba(255, 255, 255, 0.1);
}

.btn-primary:hover {
  background: var(--color-primary-hover);
}

.btn-secondary {
  background: var(--color-surface-tint);
  color: var(--color-primary-brand);
  border-color: var(--color-secondary-ice);
}

.btn-secondary:hover {
  background: var(--color-surface-high);
}

.btn-outline {
  background: transparent;
  color: var(--color-on-surface-variant);
  border-color: var(--color-outline-variant);
}

.btn-outline:hover {
  background: var(--color-surface-container);
  color: var(--color-on-surface);
  border-color: var(--color-primary-brand);
}

.btn-sm {
  padding: 3px var(--space-xs);
  font-size: 0.75rem;
}

.btn-danger {
  background: #fee2e2;
  color: var(--color-error);
  border-color: #fca5a5;
}

.btn-danger:hover {
  background: #fecaca;
}

/* Footer */
.app-footer {
  margin-top: auto;
  background: var(--color-surface-lowest);
  border-top: 1px solid var(--color-border-subtle);
  padding: var(--space-md) 0;
  font-size: 0.8125rem;
  color: var(--color-on-surface-variant);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.footer-brand-wrap {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.footer-logo-link {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

.footer-logo {
  height: 24px;
  width: auto;
  object-fit: contain;
  opacity: 0.9;
}

.footer-credits {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  flex-wrap: wrap;
  font-family: var(--font-body);
  font-size: 0.8125rem;
}

.credit-divider {
  color: var(--color-on-surface-variant);
  opacity: 0.5;
}

.footer-copyright {
  font-family: var(--font-body);
  font-size: 0.8125rem;
}

.footer-link {
  color: var(--color-primary-brand);
  text-decoration: none;
  font-weight: 600;
  transition: color 0.15s ease;
}

.footer-link:hover {
  text-decoration: underline;
  color: var(--color-primary-hover);
}

/* Utilities */
.text-muted {
  color: var(--color-on-surface-variant);
}

.text-primary {
  color: var(--color-primary-brand);
}

.text-mono {
  font-family: var(--font-mono);
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}