/* ===== CSS Variables for Theming ===== */
:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --border: #e0e0e0;
  --accent: #000000;
  --muted: #666666;
  --hover: #f5f5f5;

  --premium: #fbbf24;
  --comfortable: #22d3ee;
  --adventure: #34d399;
  --success: #10b981;
  --error: #ef4444;

  --maxw: 920px;
}

[data-theme="dark"] {
  --bg: #0a0a0a;
  --fg: #e0e0e0;
  --border: #2a2a2a;
  --accent: #ffffff;
  --muted: #888888;
  --hover: #1a1a1a;
}

/* ===== Base Styles ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: clamp(14px, 1vw, 16px);
}

body {
  font-family: 'JetBrains Mono', monospace;
  background-color: var(--bg);
  color: var(--fg);
  line-height: 1.6;
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* ===== Topbar ===== */
.topbar {
  position: sticky;
  top: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  border-bottom: 1px solid var(--border);
  background-color: var(--bg);
  z-index: 100;
}

.topbar h1 {
  font-size: 1.5rem;
  font-weight: 700;
}

.header-actions {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.reset-btn {
  background: none;
  border: 1px solid var(--border);
  color: var(--fg);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  transition: border-color 0.2s ease, background-color 0.2s ease;
  font-family: 'JetBrains Mono', monospace;
}

.reset-btn:hover {
  border-color: var(--accent);
  background-color: var(--hover);
}

.lang-toggle {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--fg);
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  padding: 0.5rem 0.75rem;
  border-radius: 4px;
  transition: border-color 0.2s ease;
}

.lang-toggle:hover {
  border-color: var(--accent);
}

.lang-toggle:focus {
  outline: none;
  border-color: var(--accent);
}

.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  color: var(--fg);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.5rem;
  border-radius: 4px;
  transition: border-color 0.2s ease;
}

.theme-toggle:hover {
  border-color: var(--accent);
}

/* ===== Container ===== */
.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 2rem;
}

/* ===== Intro Section ===== */
.intro {
  margin-bottom: 3rem;
}

.subtitle {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.description {
  color: var(--muted);
  margin-bottom: 1rem;
}

/* ===== Forms ===== */
.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border);
  background-color: var(--bg);
  color: var(--fg);
  font-family: 'JetBrains Mono', monospace;
  font-size: 1rem;
  border-radius: 4px;
  transition: border-color 0.2s ease;
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--accent);
}

.help-text {
  display: block;
  margin-top: 0.25rem;
  color: var(--muted);
  font-size: 0.875rem;
}

/* ===== Buttons ===== */
.btn {
  padding: 0.75rem 1.5rem;
  border: 1px solid var(--border);
  background-color: var(--bg);
  color: var(--fg);
  font-family: 'JetBrains Mono', monospace;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  border-radius: 4px;
  transition: all 0.2s ease;
}

.btn:hover:not(:disabled) {
  background-color: var(--hover);
  border-color: var(--accent);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-primary {
  background-color: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
}

.btn-primary:hover:not(:disabled) {
  opacity: 0.9;
}

/* ===== Loading Spinner ===== */
.loading {
  text-align: center;
  padding: 2rem;
}

.spinner {
  display: inline-block;
  width: 40px;
  height: 40px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ===== Error ===== */
.error {
  padding: 1rem;
  margin: 1rem 0;
  border: 1px solid var(--error);
  background-color: rgba(239, 68, 68, 0.1);
  color: var(--error);
  border-radius: 4px;
}

/* ===== Category List ===== */
.category-list,
.travel-type-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.category-item,
.travel-type-item {
  padding: 0.75rem 1rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s ease;
  text-align: left;
}

.category-item:hover,
.travel-type-item:hover {
  background-color: var(--hover);
  border-color: var(--accent);
}

.category-item.selected,
.travel-type-item.selected {
  background-color: var(--hover);
  border-color: var(--accent);
  border-width: 2px;
  font-weight: 600;
}

.category-item.disabled,
.travel-type-item.disabled {
  opacity: 0.4;
  cursor: not-allowed;
  color: var(--muted);
}

.category-item.disabled:hover,
.travel-type-item.disabled:hover {
  background-color: var(--bg);
  border-color: var(--border);
}

.soon-badge {
  font-size: 0.75rem;
  color: var(--muted);
  font-weight: 400;
  margin-left: 0.5rem;
}

/* ===== Events List ===== */
.events-list {
  margin: 2rem 0;
}

.events-list h2 {
  margin-bottom: 1rem;
}

.event-card {
  padding: 1rem;
  margin-bottom: 0.5rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.event-card:hover {
  background-color: var(--hover);
  border-color: var(--accent);
}

.event-card.selected {
  background-color: var(--hover);
  border-color: var(--accent);
  border-width: 2px;
}

.event-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.event-card p {
  font-size: 0.875rem;
  color: var(--muted);
}

/* ===== Trip Summary ===== */
.trip-summary {
  padding: 1.5rem;
  margin-bottom: 2rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background-color: var(--hover);
}

.trip-summary h3 {
  margin-bottom: 1rem;
}

.trip-summary p {
  margin-bottom: 0.5rem;
}

/* ===== Pricing Options ===== */
.pricing-tier {
  margin-bottom: 2rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  overflow: hidden;
}

.tier-header {
  padding: 1rem;
  background-color: var(--hover);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
  user-select: none;
  transition: background-color 0.2s ease;
}

.tier-header:hover {
  background-color: var(--border);
}

.tier-header.premium { border-left: 4px solid var(--premium); }
.tier-header.comfortable { border-left: 4px solid var(--comfortable); }
.tier-header.adventure { border-left: 4px solid var(--adventure); }

.tier-toggle {
  font-size: 1.25rem;
  transition: transform 0.2s ease;
}

.tier-toggle.open {
  transform: rotate(180deg);
}

.tier-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.tier-content.open {
  max-height: 5000px;
}

.tier-details {
  padding: 1.5rem;
}

.detail-section {
  margin-bottom: 1.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
}

.detail-section:last-child {
  border-bottom: none;
}

.detail-section h4 {
  font-size: 1rem;
  margin-bottom: 0.75rem;
  font-weight: 600;
}

.detail-section p {
  margin-bottom: 0.25rem;
  font-size: 0.875rem;
}

.detail-label {
  color: var(--muted);
  display: inline-block;
  min-width: 120px;
}

.total-cost {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--success);
  margin-top: 1rem;
}

/* ===== Email Section ===== */
.email-section {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

.email-section h3 {
  margin-bottom: 1rem;
}

.success-message {
  padding: 1rem;
  margin-top: 1rem;
  border: 1px solid var(--success);
  background-color: rgba(16, 185, 129, 0.1);
  color: var(--success);
  border-radius: 4px;
  font-weight: 500;
}

/* ===== Footer ===== */
.footer {
  text-align: center;
  padding: 2rem;
  margin-top: 4rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.875rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.footer-links a {
  color: var(--fg);
  text-decoration: none;
  font-weight: 500;
  transition: opacity 0.2s ease;
}

.footer-links a:hover {
  opacity: 0.7;
}

.footer-version {
  font-size: 0.75rem;
  color: var(--muted);
  opacity: 0.5;
}

.footer a {
  color: var(--fg);
  text-decoration: none;
  font-weight: 500;
  transition: opacity 0.2s ease;
}

.footer a:hover {
  opacity: 0.7;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .container {
    padding: 1rem;
  }

  .topbar {
    padding: 1rem;
  }

  .detail-label {
    min-width: 100px;
  }
}