*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #ffffff;
  --bg-secondary: #f8f9fa;
  --text: #1a1a2e;
  --text-secondary: #555;
  --border: #e5e7eb;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --card-bg: #ffffff;
  --shadow: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-hover: 0 8px 25px rgba(0,0,0,0.12);
  --radius: 10px;
  --transition: 0.2s ease;
}

[data-theme="dark"] {
  --bg: #0f172a;
  --bg-secondary: #1e293b;
  --text: #e2e8f0;
  --text-secondary: #94a3b8;
  --border: #334155;
  --accent: #60a5fa;
  --accent-hover: #93bbfd;
  --card-bg: #1e293b;
  --shadow: 0 1px 3px rgba(0,0,0,0.3);
  --shadow-hover: 0 8px 25px rgba(0,0,0,0.4);
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  -webkit-tap-highlight-color: transparent;
  -webkit-touch-callout: none;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background var(--transition), color var(--transition);
}

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

a:hover {
  color: var(--accent-hover);
}

img {
  max-width: 100%;
  display: block;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.header {
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
  background: rgba(255,255,255,0.9);
}

[data-theme="dark"] .header {
  background: rgba(15,23,42,0.9);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: calc(64px + env(safe-area-inset-top));
  padding-top: env(safe-area-inset-top);
}

.logo {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text);
  letter-spacing: -0.5px;
}

.logo:hover {
  color: var(--accent);
}

.nav {
  display: flex;
  gap: 8px;
}

.nav-link {
  color: var(--text-secondary);
  padding: 8px 14px;
  border-radius: 6px;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all var(--transition);
}

.nav-link:hover,
.nav-link.active {
  color: var(--accent);
  background: var(--bg-secondary);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.theme-toggle,
.menu-toggle {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  color: var(--text);
  width: 40px;
  height: 40px;
  border-radius: 8px;
  font-size: 1.2rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
}

.theme-toggle:hover,
.menu-toggle:hover {
  background: var(--border);
}

.menu-toggle {
  display: none;
}

/* Article Time */
.article-time {
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Buttons */
.btn {
  display: inline-block;
  background: var(--accent);
  color: white;
  padding: 10px 24px;
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  text-align: center;
}

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

.btn-sm {
  padding: 8px 18px;
  font-size: 0.85rem;
}

/* Content Grid */
.content-grid {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 40px;
  margin-bottom: 60px;
}

.section-title {
  font-size: 1.3rem;
  font-weight: 800;
  margin-bottom: 20px;
  letter-spacing: -0.3px;
}

/* Article Cards */
.article-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: all var(--transition);
  display: block;
  color: var(--text);
  text-decoration: none;
  touch-action: manipulation;
}

.card:hover,
.card:focus-visible {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.card:hover .card-body h3,
.card:focus-visible .card-body h3 {
  color: var(--accent);
}

.card-image {
  height: 160px;
  overflow: hidden;
}

.card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.card-body {
  padding: 20px;
}

.card-category {
  display: inline-block;
  background: var(--bg-secondary);
  color: var(--accent);
  padding: 2px 10px;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 10px;
}

.card-body h3 {
  font-size: 1.05rem;
  line-height: 1.35;
  margin-bottom: 8px;
  font-weight: 700;
  color: var(--text);
  transition: color var(--transition);
}

.card-body h3 a {
  color: var(--text);
}

.card-body p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 12px;
}

/* Sidebar */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.sidebar-widget {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
}

.widget-title {
  font-size: 1rem;
  font-weight: 800;
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--border);
}

.trending-list {
  list-style: none;
  counter-reset: trend;
}

.trending-list li {
  counter-increment: trend;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.trending-list li:last-child {
  border-bottom: none;
}

.trending-list li::before {
  content: counter(trend);
  font-weight: 800;
  font-size: 1.1rem;
  color: var(--accent);
}

.trending-list li a {
  color: var(--text);
  font-weight: 600;
  font-size: 0.9rem;
}

.trending-list li a:hover {
  color: var(--accent);
}

.trending-count {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.newsletter p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 14px;
}

.newsletter-form {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.newsletter-form input {
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.9rem;
  background: var(--bg);
  color: var(--text);
  outline: none;
  transition: border var(--transition);
}

.newsletter-form input:focus {
  border-color: var(--accent);
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag {
  display: inline-block;
  background: var(--bg-secondary);
  color: var(--text-secondary);
  padding: 5px 14px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
  border: 1px solid var(--border);
  transition: all var(--transition);
}

.tag:hover {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

/* Ad Slots */
.ad-slot {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  margin: 20px 0;
  padding: 12px;
  background: var(--bg-secondary);
  border: 1px dashed var(--border);
  border-radius: 8px;
  overflow: hidden;
  text-align: center;
}

.ad-label {
  font-size: 0.65rem;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--text-secondary);
  opacity: 0.7;
}

.ad-inner {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.ad-inner ins,
.ad-inner iframe,
.ad-inner video,
.ad-inner img {
  max-width: 100%;
}

.ad-placeholder {
  color: var(--text-secondary);
  font-size: 0.8rem;
  opacity: 0.6;
  padding: 8px;
}

.ad-slot.ad-in-grid {
  grid-column: 1 / -1;
}

.ad-slot.ad-grid {
  grid-column: 1 / -1;
}

@media (max-width: 480px) {
  .ad-slot {
    margin: 14px 0;
    padding: 8px;
  }
}

/* Article Pages */
.article-page {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  margin: 30px 0 16px;
}

.article-header {
  padding: 32px 40px 8px;
  max-width: 860px;
}

.article-title {
  font-size: 2rem;
  line-height: 1.25;
  font-weight: 800;
  margin: 12px 0;
  letter-spacing: -0.5px;
}

.article-deck {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 14px;
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 20px;
}

.byline {
  font-weight: 600;
  font-size: 0.9rem;
}

.article-image {
  width: 100%;
  aspect-ratio: 15 / 7;
  overflow: hidden;
  background: var(--bg-secondary);
}

.article-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.article-body {
  padding: 28px 40px 40px;
  max-width: 860px;
}

.article-body p {
  margin-bottom: 18px;
  color: var(--text-secondary);
  font-size: 1.05rem;
  line-height: 1.7;
}

.article-source {
  padding: 12px 16px;
  background: var(--bg-secondary);
  border-radius: 8px;
  border: 1px solid var(--border);
  font-size: 0.9rem;
  color: var(--text-secondary);
}

@media (max-width: 480px) {
  .article-header,
  .article-body {
    padding-left: 20px;
    padding-right: 20px;
  }

  .article-title {
    font-size: 1.5rem;
  }

  .article-deck {
    font-size: 1rem;
  }

  .article-meta {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }
}

/* Touch targets */
.theme-toggle,
.menu-toggle,
.btn,
.tag,
.nav-link,
.trending-list li a {
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}

/* Footer */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  margin-top: 40px;
}

.footer-inner {
  padding: 40px 20px calc(40px + env(safe-area-inset-bottom));
  text-align: center;
}

.footer-logo {
  font-size: 1.2rem;
  font-weight: 800;
  margin-bottom: 16px;
}

.footer-nav {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-bottom: 16px;
}

.footer-nav a {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.footer-nav a:hover {
  color: var(--accent);
}

.footer-copy {
  color: var(--text-secondary);
  font-size: 0.8rem;
}

/* Responsive */
@media (max-width: 900px) {
  .nav {
    display: none;
    position: absolute;
    top: calc(64px + env(safe-area-inset-top));
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 12px 20px;
    gap: 4px;
  }

  .nav.open {
    display: flex;
  }

  .menu-toggle {
    display: flex;
  }

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

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

@media (max-width: 480px) {
  .header-inner {
    height: calc(56px + env(safe-area-inset-top));
  }

  .nav {
    top: calc(56px + env(safe-area-inset-top));
  }

  .logo {
    font-size: 1.2rem;
  }

  .sidebar-widget {
    padding: 18px;
  }

  .theme-toggle,
  .menu-toggle,
  .btn {
    min-height: 44px;
    min-width: 44px;
  }

  .nav-link {
    padding: 12px 14px;
  }

  .newsletter-form input {
    font-size: 16px;
    padding: 12px 14px;
  }

  .btn-sm {
    min-height: 40px;
  }

  .card-body {
    padding: 16px;
  }

  .card-image {
    height: 180px;
  }

  .footer-nav {
    gap: 16px;
    flex-wrap: wrap;
  }
}

@media (max-width: 340px) {
  .card-image {
    height: 150px;
  }

  .card-image img {
    object-position: center;
  }

  .article-title {
    font-size: 1.3rem;
  }
}