/* ===== CSS Variables ===== */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #60a5fa;
  --gray-50: #f8fafc;
  --gray-100: #f1f5f9;
  --gray-200: #e2e8f0;
  --gray-300: #cbd5e1;
  --gray-400: #94a3b8;
  --gray-500: #64748b;
  --gray-600: #475569;
  --gray-700: #334155;
  --gray-800: #1e293b;
  --gray-900: #0f172a;
  --radius: 6px;
  --shadow: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --transition: 0.2s ease;
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--gray-50);
  color: var(--gray-800);
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--primary-dark);
}

img {
  max-width: 100%;
  height: auto;
}

/* ===== Container ===== */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== Header ===== */
header {
  background: white;
  border-bottom: 1px solid var(--gray-200);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow);
}

header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.logo {
  font-size: 20px;
  font-weight: 700;
  color: var(--gray-900);
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo svg {
  width: 28px;
  height: 28px;
}

.logo span {
  color: var(--primary);
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 4px;
}

.nav-links a {
  display: block;
  padding: 8px 14px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  color: var(--gray-600);
  transition: all var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  background: var(--gray-100);
  color: var(--primary);
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--gray-700);
  border-radius: 2px;
  transition: all var(--transition);
}

/* Mobile Nav */
.mobile-nav {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 200;
  background: rgba(15, 23, 42, 0.4);
  backdrop-filter: blur(4px);
}

.mobile-nav.open {
  display: block;
}

.mobile-nav-inner {
  position: absolute;
  top: 0;
  right: 0;
  width: 260px;
  height: 100%;
  background: white;
  padding: 24px 20px;
  box-shadow: -4px 0 24px rgba(0,0,0,0.15);
  animation: slideIn 0.25s ease;
}

@keyframes slideIn {
  from { transform: translateX(100%); }
  to { transform: translateX(0); }
}

.mobile-nav-close {
  position: absolute;
  top: 12px;
  right: 12px;
  background: none;
  border: none;
  font-size: 24px;
  color: var(--gray-500);
  cursor: pointer;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: background var(--transition);
}

.mobile-nav-close:hover {
  background: var(--gray-100);
}

.mobile-nav-inner ul {
  list-style: none;
  margin-top: 40px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.mobile-nav-inner a {
  display: block;
  padding: 10px 14px;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 500;
  color: var(--gray-700);
  transition: all var(--transition);
}

.mobile-nav-inner a:hover,
.mobile-nav-inner a.active {
  background: var(--gray-100);
  color: var(--primary);
}

/* ===== Main ===== */
main {
  min-height: calc(100vh - 60px - 52px);
  padding: 32px 0;
}

/* ===== Typography ===== */
h1 {
  font-size: 28px;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 16px;
  line-height: 1.3;
}

h2 {
  font-size: 22px;
  font-weight: 600;
  color: var(--gray-900);
  margin-top: 28px;
  margin-bottom: 12px;
  line-height: 1.35;
}

h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--gray-800);
  margin-top: 20px;
  margin-bottom: 10px;
}

p {
  margin-bottom: 12px;
  color: var(--gray-700);
  line-height: 1.65;
}

/* ===== Tables ===== */
table {
  width: 100%;
  border-collapse: collapse;
  table-layout: auto;
  margin: 16px 0;
  font-size: 14px;
}

th {
  background: var(--gray-100);
  padding: 8px 10px;
  text-align: left;
  font-weight: 600;
  font-size: 12px;
  color: var(--gray-700);
  border-bottom: 2px solid var(--gray-200);
  white-space: normal;
  overflow-wrap: break-word;
  line-height: 1.3;
}

td {
  padding: 8px 10px;
  border-bottom: 1px solid var(--gray-200);
  color: var(--gray-700);
  white-space: nowrap;
}

tr:hover td {
  background: var(--gray-50);
}

/* ===== Code ===== */
code {
  background: var(--gray-100);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 13px;
  color: var(--primary-dark);
}

pre {
  background: var(--gray-800);
  color: #e2e8f0;
  padding: 16px;
  border-radius: var(--radius);
  overflow-x: auto;
  margin: 16px 0;
  font-size: 13px;
  line-height: 1.55;
}

pre code {
  background: none;
  padding: 0;
  color: inherit;
}

/* ===== Cards / Grid ===== */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 16px;
  margin: 20px 0;
}

.card {
  background: white;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 20px;
  transition: all var(--transition);
}

.card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--primary-light);
}

.card h3 {
  margin-top: 0;
  font-size: 16px;
}

.card p {
  font-size: 13px;
  color: var(--gray-500);
  margin-bottom: 0;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  border: 1px solid var(--gray-200);
  background: white;
  color: var(--gray-700);
  text-decoration: none;
}

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

/* ===== Footer ===== */
footer {
  background: var(--gray-900);
  color: var(--gray-400);
  padding: 0;
  font-size: 13px;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
  height: 52px;
}

.footer-inner a {
  color: var(--gray-300);
}

.footer-inner a:hover {
  color: white;
}

/* ===== Section Layout ===== */
section, .hero-section, .features-section, .latest-section, .brands-section, .guide-section {
  padding: 40px 0;
}

section:nth-child(even),
.features-section:nth-child(even),
.brands-section:nth-child(even) {
  background: white;
}

/* ===== Home Page ===== */
.hero {
  text-align: center;
  padding: 48px 0 32px;
}

.hero h1 {
  font-size: 32px;
  margin-bottom: 12px;
}

.hero p {
  font-size: 16px;
  color: var(--gray-500);
  max-width: 560px;
  margin: 0 auto 24px;
}

.hero-section {
  text-align: center;
  padding: 56px 0 40px;
}

.hero-section h1 {
  font-size: 32px;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 12px;
}

.hero-section p {
  font-size: 16px;
  color: var(--gray-500);
  max-width: 560px;
  margin: 0 auto 28px;
}

.hero-buttons {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 22px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  background: var(--primary);
  color: white;
  border: 1px solid var(--primary);
  text-decoration: none;
}

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

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 22px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  background: white;
  color: var(--gray-700);
  border: 1px solid var(--gray-300);
  text-decoration: none;
}

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

/* Features */
.features-section {
  background: white;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.feature-card {
  text-align: center;
  padding: 28px 20px;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  background: var(--gray-50);
  transition: all var(--transition);
}

.feature-card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--primary-light);
}

.feature-icon {
  font-size: 36px;
  margin-bottom: 12px;
}

.feature-card h3 {
  font-size: 16px;
  margin-top: 0;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 13px;
  color: var(--gray-500);
  margin-bottom: 0;
}

/* Latest / Articles */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
}

.section-header h2 {
  margin: 0;
}

.more-link {
  font-size: 13px;
  font-weight: 500;
  color: var(--primary);
}

.more-link:hover {
  color: var(--primary-dark);
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
}

.article-card {
  background: white;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 20px;
  transition: box-shadow var(--transition);
}

.article-card:hover {
  box-shadow: var(--shadow-md);
}

.article-card h3 {
  font-size: 16px;
  margin-top: 0;
  margin-bottom: 8px;
}

.article-card h3 a {
  color: var(--gray-900);
}

.article-card h3 a:hover {
  color: var(--primary);
}

.article-excerpt {
  font-size: 13px;
  color: var(--gray-500);
  margin-bottom: 10px;
}

.article-date {
  font-size: 12px;
  color: var(--gray-400);
  margin-bottom: 0;
}

/* Brands */
.brands-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.brand-item {
  padding: 10px 20px;
  background: white;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  color: var(--gray-700);
  transition: all var(--transition);
}

.brand-item:hover {
  border-color: var(--primary);
  color: var(--primary);
}

/* Guide CTA */
.guide-card {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border-radius: var(--radius);
  padding: 40px;
  color: white;
}

.guide-content h2 {
  color: white;
  margin-top: 0;
}

.guide-content p {
  color: rgba(255,255,255,0.85);
  margin-bottom: 20px;
}

.guide-content .btn-primary {
  background: white;
  color: var(--primary);
  border-color: white;
}

.guide-content .btn-primary:hover {
  background: var(--gray-100);
}

/* ===== Selector Tool ===== */
.selector-page h1,
.tech-page h1,
.guide-page h1 {
  margin-bottom: 8px;
}

.page-description {
  font-size: 15px;
  color: var(--gray-500);
  margin-bottom: 24px;
}

.filters-container {
  background: white;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 20px;
}

.filter-row,
.input-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.filter-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  flex: 0 0 auto;
}

.filter-group select,
.filter-group input {
  width: auto;
  min-width: 0;
  max-width: 160px;
}

.filter-group label {
  font-size: 12px;
  font-weight: 600;
  color: var(--gray-500);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.filter-group select,
.filter-group input {
  padding: 8px 12px;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 14px;
  color: var(--gray-800);
  background: white;
  transition: border-color var(--transition);
  font-family: inherit;
}

.filter-group select:focus,
.filter-group input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37,99,235,0.1);
}

.results-container {
  margin-top: 8px;
}

.results-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

#result-count {
  font-size: 13px;
  color: var(--gray-500);
}

#reset-btn {
  padding: 6px 14px;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  background: white;
  font-size: 13px;
  color: var(--gray-600);
  cursor: pointer;
  transition: all var(--transition);
  font-family: inherit;
}

#reset-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.table-container {
  overflow-x: auto;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
}

.table-container table {
  margin: 0;
}

.table-container th {
  background: var(--gray-100);
  position: sticky;
  top: 0;
}

.no-results {
  display: none;
  text-align: center;
  padding: 40px 20px;
  color: var(--gray-400);
  font-size: 14px;
}

/* ===== Tech Page ===== */
.subtitle {
  font-size: 15px;
  color: var(--gray-500);
  margin-bottom: 28px;
}

.tech-categories {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.category-card {
  background: white;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 24px;
  transition: all var(--transition);
}

.category-card:hover {
  box-shadow: var(--shadow-md);
}

.category-card h3 {
  font-size: 17px;
  margin-top: 0;
  margin-bottom: 8px;
}

.category-card p {
  font-size: 13px;
  color: var(--gray-500);
  margin-bottom: 12px;
}

.category-card ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.category-card li {
  padding: 6px 0;
  border-bottom: 1px solid var(--gray-100);
}

.category-card li:last-child {
  border-bottom: none;
}

.category-card li a {
  font-size: 14px;
  color: var(--gray-700);
}

.category-card li a:hover {
  color: var(--primary);
}

/* ===== Guide Page ===== */
.guide-content {
  max-width: 800px;
}

.guide-section {
  margin-bottom: 36px;
  border-bottom: 1px solid var(--gray-200);
  padding-bottom: 24px;
}

.guide-section:last-child {
  border-bottom: none;
  margin-bottom: 0;
}

.guide-section h2 {
  margin-top: 0;
}

.steps-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.step-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.step-number {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--primary);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 700;
}

.step-content h3 {
  margin-top: 0;
  font-size: 16px;
  margin-bottom: 4px;
}

.step-content p {
  font-size: 14px;
  color: var(--gray-600);
  margin-bottom: 0;
}

.params-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 16px;
}

.param-card {
  background: white;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 20px;
}

.param-card h3 {
  font-size: 15px;
  margin-top: 0;
  margin-bottom: 8px;
}

.param-card p {
  font-size: 13px;
  color: var(--gray-500);
  margin-bottom: 0;
}

.scenarios-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
}

.scenario-card {
  background: var(--gray-50);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius);
  padding: 24px;
}

.scenario-card h3 {
  font-size: 16px;
  margin-top: 0;
  margin-bottom: 10px;
}

.scenario-card ul {
  list-style: disc;
  padding-left: 18px;
  margin: 0;
  font-size: 14px;
  color: var(--gray-600);
}

.scenario-card li {
  margin-bottom: 6px;
}

.scenario-card li:last-child {
  margin-bottom: 0;
}

.brands-compare table {
  margin-top: 0;
}

/* ===== Post Meta ===== */
.post-meta {
  font-size: 13px;
  color: var(--gray-400);
  margin-bottom: 20px;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .nav-links {
    display: none;
  }

  .hamburger {
    display: flex;
  }

  h1 { font-size: 24px; }
  h2 { font-size: 20px; }
  .hero h1 { font-size: 26px; }
  .hero-section h1 { font-size: 26px; }

  table {
    font-size: 13px;
  }

  th, td {
    padding: 8px 10px;
  }

  .grid {
    grid-template-columns: 1fr;
  }

  .hero-section {
    padding: 40px 0 28px;
  }

  .hero-buttons {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-buttons .btn-primary,
  .hero-buttons .btn-secondary {
    justify-content: center;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .articles-grid {
    grid-template-columns: 1fr;
  }

  .filter-row,
  .input-row {
    flex-direction: column;
  }

  .filter-group {
    min-width: 100%;
  }

  .filter-group select,
  .filter-group input {
    width: 100%;
    max-width: 100%;
  }

  .tech-categories {
    grid-template-columns: 1fr;
  }

  .params-grid {
    grid-template-columns: 1fr;
  }

  .scenarios-list {
    grid-template-columns: 1fr;
  }

  .guide-card {
    padding: 28px 20px;
  }

  section, .hero-section, .features-section,
  .latest-section, .brands-section, .guide-section {
    padding: 28px 0;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 14px;
  }

  body {
    font-size: 14px;
  }

  h1 { font-size: 22px; }
  h2 { font-size: 18px; }
}