:root {
  color-scheme: dark;
  --bg: #0f172a;
  --surface: #111827;
  --surface-alt: #1f2937;
  --text: #f8fafc;
  --muted: #94a3b8;
  --primary: #38bdf8;
  --primary-strong: #0ea5e9;
  --accent: #f97316;
  --border: rgba(148, 163, 184, 0.18);
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  min-height: 100%;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: radial-gradient(circle at top, rgba(56, 189, 248, 0.08), transparent 28%),
              linear-gradient(180deg, #020617 0%, #090e23 100%);
  color: var(--text);
}

body {
  line-height: 1.6;
}

.container {
  width: min(1120px, calc(100% - 2rem));
  margin: 0 auto;
}

.site-header {
  padding: 1.4rem 0;
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(16px);
  background: rgba(15, 23, 42, 0.88);
  border-bottom: 1px solid rgba(148, 163, 184, 0.08);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
}

.subtitle {
  margin: 0.2rem 0 0;
  color: var(--muted);
}

.nav-links {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: var(--text);
}

.section-light,
.section-dark {
  padding: 4rem 0;
}

.section-dark {
  background: rgba(15, 23, 42, 0.95);
}

.hero-grid {
  display: grid;
  gap: 2rem;
  align-items: center;
  grid-template-columns: minmax(0, 1.2fr) 1fr;
}

.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.18em;
  font-size: 0.79rem;
  color: var(--primary);
  margin-bottom: 1rem;
}

h1, h2, h3 {
  margin: 0;
}

h1 {
  font-size: clamp(2.4rem, 4vw, 3.75rem);
  line-height: 1.02;
}

h2 {
  font-size: clamp(1.65rem, 2vw, 2.5rem);
}

.hero p,
.feature-card p,
.tip-card p,
.hero-card-body p {
  color: var(--muted);
}

.hero-actions {
  margin-top: 2rem;
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.95rem 1.6rem;
  border-radius: 999px;
  border: 1px solid transparent;
  text-decoration: none;
  font-weight: 600;
  transition: transform 0.2s ease, background-color 0.2s ease, border-color 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--primary);
  color: #0f172a;
}

.btn-outline {
  background: transparent;
  border-color: rgba(56, 189, 248, 0.4);
  color: var(--text);
}

.hero-card {
  background: linear-gradient(180deg, rgba(255,255,255,0.05), rgba(15,23,42,0.9));
  border: 1px solid rgba(148, 163, 184, 0.18);
  border-radius: 1.5rem;
  overflow: hidden;
  box-shadow: 0 30px 80px rgba(15, 23, 42, 0.35);
}

.hero-card-image {
  border-radius: 0;
}

.hero-card-body {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 2rem;
}

.card-label {
  display: inline-flex;
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  background: rgba(56, 189, 248, 0.14);
  color: var(--primary);
  font-size: 0.8rem;
  font-weight: 700;
}

.featured-grid,
.models-grid,
.tips-grid {
  display: grid;
  gap: 1.5rem;
}

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

.card-image {
  display: block;
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  background: var(--surface-alt);
}

.feature-card,
.model-card,
.tip-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 1.3rem;
  overflow: hidden;
}

.feature-card h3,
.feature-card p,
.feature-card ul,
.model-card-body,
.tip-card {
  padding-left: 1.8rem;
  padding-right: 1.8rem;
}

.feature-card h3 {
  padding-top: 1.4rem;
  margin-bottom: 0.6rem;
}

.feature-card p {
  margin: 0 0 0.8rem;
}

.feature-card ul {
  margin: 0;
  padding-bottom: 1.8rem;
}

.model-card {
  position: relative;
  display: flex;
  flex-direction: column;
}

.model-card-body {
  padding: 1.4rem 1.8rem 1.8rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.tip-card {
  padding: 1.8rem;
}

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

.model-card h3 {
  margin-bottom: 0.8rem;
}

.model-card p,
.model-card li {
  margin: 0;
}

.model-card ul {
  list-style: none;
  padding: 0;
  margin: 1rem 0 0;
  display: grid;
  gap: 0.55rem;
}

.model-card li::before {
  content: "✔";
  display: inline-block;
  margin-right: 0.65rem;
  color: var(--primary);
}

.models-tools {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin: 1.5rem 0 0.75rem;
}

.search-field {
  min-width: 220px;
  flex: 1 1 240px;
  display: grid;
  gap: 0.45rem;
}

.search-field label {
  font-size: 0.85rem;
  color: var(--muted);
}

.search-field input {
  width: 100%;
  padding: 0.95rem 1rem;
  border-radius: 0.95rem;
  border: 1px solid rgba(148, 163, 184, 0.18);
  background: rgba(255, 255, 255, 0.05);
  color: var(--text);
}

.search-field input::placeholder {
  color: rgba(255, 255, 255, 0.6);
}

.result-count {
  color: var(--text);
  font-weight: 600;
  min-width: 160px;
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin: 1.75rem 0 2rem;
}

.filter-btn {
  border: 1px solid rgba(148, 163, 184, 0.18);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  padding: 0.9rem 1.2rem;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease;
}

.filter-btn:hover,
.filter-btn.active {
  background: rgba(56, 189, 248, 0.16);
  color: var(--primary);
}

.tips-grid {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.tip-card {
  min-height: 220px;
}

.site-footer {
  padding: 2.5rem 0;
  border-top: 1px solid rgba(148, 163, 184, 0.12);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  color: var(--muted);
}

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

@media (max-width: 720px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .nav-links {
    width: 100%;
    justify-content: flex-start;
  }
}