:root {
  --sd-bg: #050816;
  --sd-bg-alt: #0b1020;
  --sd-accent: #f5c542;
  --sd-accent-soft: #f5c54233;
  --sd-text: #f9fafb;
  --sd-muted: #9ca3af;
  --sd-card-bg: #111827;
  --sd-border: #1f2937;
  --sd-danger: #ef4444;
  --sd-success: #22c55e;
  --sd-font: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--sd-font);
  background: radial-gradient(circle at top, #111827 0, var(--sd-bg) 40%, #000 100%);
  color: var(--sd-text);
}

/* Header */

.sd-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  border-bottom: 1px solid var(--sd-border);
  background: rgba(5, 8, 22, 0.95);
  backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 20;
}

.sd-logo {
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--sd-accent);
}

.sd-nav {
  display: flex;
  gap: 0.5rem;
  align-items: center;
}

.sd-nav-link {
  color: var(--sd-muted);
  text-decoration: none;
  font-size: 0.9rem;
}

.sd-nav-link:hover {
  color: var(--sd-text);
}

.sd-nav-pill {
  border: 1px solid var(--sd-border);
  background: var(--sd-bg-alt);
  color: var(--sd-muted);
  padding: 0.3rem 0.8rem;
  border-radius: 999px;
  font-size: 0.8rem;
  cursor: pointer;
}

.sd-nav-pill:hover {
  color: var(--sd-text);
  border-color: var(--sd-accent);
}

.sd-nav-pill-muted {
  cursor: default;
}

/* Main */

.sd-main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 2rem;
}

.sd-footer {
  padding: 1rem 2rem;
  border-top: 1px solid var(--sd-border);
  font-size: 0.8rem;
  color: var(--sd-muted);
  text-align: center;
}

/* Hero */

.sd-hero {
  text-align: center;
  margin-bottom: 2rem;
}

.sd-hero h1 {
  font-size: 2.4rem;
  margin-bottom: 0.4rem;
}

.sd-hero p {
  max-width: 640px;
  margin: 0 auto 1.5rem;
  color: var(--sd-muted);
}

.sd-search-bar {
  display: inline-flex;
  gap: 0.5rem;
  background: var(--sd-bg-alt);
  padding: 0.5rem;
  border-radius: 999px;
  border: 1px solid var(--sd-border);
}

.sd-search-bar input {
  border: none;
  background: transparent;
  color: var(--sd-text);
  padding: 0.4rem 0.8rem;
  min-width: 220px;
}

.sd-search-bar input:focus {
  outline: none;
}

.sd-search-bar button {
  border: none;
  background: var(--sd-accent);
  color: #111827;
  padding: 0.4rem 1rem;
  border-radius: 999px;
  cursor: pointer;
  font-weight: 600;
}

.sd-hero-tags {
  margin-top: 1rem;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}

/* Tags */

.sd-tag {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.7rem;
  border-radius: 999px;
  border: 1px solid var(--sd-border);
  font-size: 0.75rem;
  color: var(--sd-muted);
}

.sd-tag-primary {
  border-color: #22c55e;
  color: #bbf7d0;
}

.sd-tag-satellite {
  border-color: #3b82f6;
  color: #bfdbfe;
}

/* Base grid */

.sd-base-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.sd-base-card {
  background: var(--sd-card-bg);
  border-radius: 1rem;
  padding: 1.2rem;
  border: 1px solid var(--sd-border);
  position: relative;
  overflow: hidden;
}

.sd-base-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at top right, var(--sd-accent-soft), transparent 60%);
  opacity: 0.4;
  pointer-events: none;
}

.sd-base-card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 0.5rem;
}

.sd-base-card-header h2 {
  margin: 0;
  font-size: 1.2rem;
}

.sd-muted {
  color: var(--sd-muted);
}

.sd-airport {
  font-size: 0.85rem;
  margin-bottom: 0.6rem;
}

.sd-base-code {
  font-weight: 700;
  font-size: 1.4rem;
  letter-spacing: 0.08em;
  color: var(--sd-accent);
}

.sd-base-tags {
  display: flex;
  gap: 0.4rem;
  margin-bottom: 0.6rem;
}

.sd-card-sub {
  font-size: 0.85rem;
  color: var(--sd-muted);
}

.sd-card-actions {
  margin-top: 0.8rem;
}

.sd-btn {
  display: inline-block;
  padding: 0.45rem 1rem;
  border-radius: 999px;
  background: var(--sd-accent-soft);
  color: var(--sd-accent);
  text-decoration: none;
  font-size: 0.85rem;
  border: 1px solid var(--sd-accent);
}

.sd-btn:hover {
  background: var(--sd-accent);
  color: #111827;
}

/* City hero / base page */

.sd-base-main {
  padding-top: 1.5rem;
}

.sd-city-hero {
  border-radius: 1.2rem;
  padding: 2rem;
  margin-bottom: 2rem;
  background-size: cover;
  background-position: center;
  position: relative;
  overflow: hidden;
}

.sd-hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, rgba(0, 0, 0, 0.3), var(--sd-bg));
}

.sd-hero-content {
  position: relative;
  z-index: 1;
}

.sd-hero-meta {
  margin-top: 0.8rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

/* Sections */

.sd-section {
  margin-bottom: 2rem;
}

.sd-section h2 {
  margin-bottom: 0.4rem;
}

.sd-section-sub {
  font-size: 0.85rem;
  color: var(--sd-muted);
  margin-bottom: 1rem;
}

/* Cards & lists */

.sd-list-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.2rem;
}

.sd-card {
  background: var(--sd-card-bg);
  border-radius: 1rem;
  padding: 1rem;
  border: 1px solid var(--sd-border);
}

.sd-card h3 {
  margin-top: 0;
}

.sd-card p {
  color: var(--sd-muted);
  font-size: 0.9rem;
}

.sd-links {
  margin-top: 0.6rem;
}

.sd-links a {
  display: inline-block;
  margin-right: 0.6rem;
  margin-bottom: 0.3rem;
  font-size: 0.8rem;
  color: var(--sd-accent);
  text-decoration: none;
}

.sd-links a:hover {
  text-decoration: underline;
}

/* Empty state */

.sd-empty {
  font-size: 0.85rem;
  color: var(--sd-muted);
  padding: 0.8rem;
  border-radius: 0.6rem;
  border: 1px dashed var(--sd-border);
}

/* Per diem */

.sd-perdiem {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  align-items: center;
  margin-bottom: 1rem;
}

.sd-perdiem label {
  font-size: 0.85rem;
}

.sd-perdiem input {
  background: var(--sd-bg-alt);
  border: 1px solid var(--sd-border);
  border-radius: 0.4rem;
  padding: 0.3rem 0.5rem;
  color: var(--sd-text);
  width: 80px;
}

.sd-perdiem button {
  border: none;
  background: var(--sd-accent);
  color: #111827;
  padding: 0.4rem 0.8rem;
  border-radius: 0.5rem;
  cursor: pointer;
  font-size: 0.85rem;
}

#perdiemResult {
  min-width: 120px;
  font-size: 0.9rem;
  color: var(--sd-success);
}

/* Layover planner */

.sd-layover-plan {
  background: var(--sd-bg-alt);
  border-radius: 1rem;
  padding: 1rem;
  border: 1px solid var(--sd-border);
}

.sd-layover-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 0.6rem;
}

.sd-layover-row label {
  font-size: 0.85rem;
}

.sd-layover-row select {
  background: var(--sd-card-bg);
  border: 1px solid var(--sd-border);
  border-radius: 0.4rem;
  padding: 0.3rem 0.6rem;
  color: var(--sd-text);
  font-size: 0.85rem;
}

.sd-layover-plan button {
  border: none;
  background: var(--sd-accent);
  color: #111827;
  padding: 0.4rem 0.8rem;
  border-radius: 0.5rem;
  cursor: pointer;
  font-size: 0.85rem;
  margin-top: 0.4rem;
}

.sd-layover-result {
  margin-top: 0.8rem;
  font-size: 0.85rem;
}

.sd-plan-list {
  list-style: none;
  padding-left: 0;
  margin: 0.4rem 0 0;
}

.sd-plan-list li {
  margin-bottom: 0.3rem;
}

/* Responsive */

@media (max-width: 768px) {
  .sd-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .sd-main {
    padding: 1.5rem;
  }

  .sd-city-hero {
    padding: 1.5rem;
  }
}