/* ========================================
   DeepML.news — Design System
   Orange-White Minimalist Theme
   ======================================== */

:root {
  --orange: #FF6D00;
  --orange-light: #FFF3E0;
  --orange-hover: #E65100;
  --dark: #111111;
  --text: #1A1A1A;
  --text-secondary: #666666;
  --text-muted: #999999;
  --bg: #FFFFFF;
  --bg-subtle: #FAFAFA;
  --border: #F0F0F0;
  --radius: 12px;
  --radius-sm: 8px;
  --font: 'Inter', 'SF Pro Display', 'Segoe UI', system-ui, -apple-system, sans-serif;
  --mono: 'JetBrains Mono', 'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
  --max-w: 1120px;
  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  font-size: 16px;
}

a {
  color: inherit;
  text-decoration: none;
  cursor: pointer;
}

button {
  cursor: pointer;
}

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

/* ── Typography ── */

h1, h2, h3 {
  line-height: 1.15;
  letter-spacing: -0.02em;
  font-weight: 800;
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); }
h2 { font-size: clamp(1.75rem, 3vw, 2.5rem); }
h3 { font-size: 1.25rem; }

.mono {
  font-family: var(--mono);
  font-size: 0.85em;
  letter-spacing: -0.02em;
}

/* ── Layout ── */

.container {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

section {
  padding: 100px 0;
}

/* ── Nav ── */

nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow var(--transition);
}

nav.scrolled {
  box-shadow: 0 1px 24px rgba(0, 0, 0, 0.06);
}

nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-logo {
  height: 28px;
  width: auto;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition);
}

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

.nav-cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 20px;
  background: var(--orange);
  color: #fff !important;
  font-weight: 600;
  font-size: 0.875rem;
  border-radius: 100px;
  transition: background var(--transition), transform var(--transition);
}

.nav-cta:hover {
  background: var(--orange-hover);
  transform: translateY(-1px);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  margin: 5px 0;
  transition: var(--transition);
  border-radius: 2px;
}

/* ── Hero ── */

.hero {
  padding: 160px 0 100px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -200px;
  right: -200px;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(255, 109, 0, 0.06) 0%, transparent 70%);
  pointer-events: none;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: var(--orange-light);
  color: var(--orange);
  font-weight: 600;
  font-size: 0.8rem;
  border-radius: 100px;
  margin-bottom: 28px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.hero-badge::before {
  content: '';
  width: 6px;
  height: 6px;
  background: var(--orange);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.hero h1 {
  max-width: 780px;
  margin: 0 auto 24px;
}

.hero h1 .accent {
  color: var(--orange);
}

.hero-sub {
  max-width: 560px;
  margin: 0 auto 40px;
  color: var(--text-secondary);
  font-size: 1.15rem;
  line-height: 1.7;
}

.hero-form {
  display: flex;
  align-items: center;
  gap: 12px;
  max-width: 460px;
  margin: 0 auto 20px;
}

.hero-form input {
  flex: 1;
  padding: 14px 20px;
  border: 1.5px solid var(--border);
  border-radius: 100px;
  font-size: 0.95rem;
  font-family: var(--font);
  outline: none;
  transition: border-color var(--transition);
  background: var(--bg);
}

.hero-form input:focus {
  border-color: var(--orange);
}

.hero-form button {
  padding: 14px 28px;
  background: var(--orange);
  color: #fff;
  border: none;
  border-radius: 100px;
  font-size: 0.95rem;
  font-weight: 600;
  font-family: var(--font);
  cursor: pointer;
  white-space: nowrap;
  transition: background var(--transition), transform var(--transition);
}

.hero-form button:hover {
  background: var(--orange-hover);
  transform: translateY(-1px);
}

.hero-note {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ── Stats ── */

.stats {
  padding: 0 0 80px;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.stat {
  background: var(--bg);
  padding: 36px 24px;
  text-align: center;
}

.stat-number {
  font-size: 2rem;
  font-weight: 800;
  color: var(--orange);
  letter-spacing: -0.02em;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 4px;
}

/* ── Features / What We Cover ── */

.features {
  background: var(--bg-subtle);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.section-header {
  text-align: center;
  max-width: 600px;
  margin: 0 auto 64px;
}

.section-header p {
  color: var(--text-secondary);
  margin-top: 12px;
  font-size: 1.05rem;
}

.section-label {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--orange);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 12px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 28px;
  cursor: default;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.feature-card:hover {
  border-color: var(--orange);
  box-shadow: 0 8px 32px rgba(255, 109, 0, 0.08);
  transform: translateY(-2px);
}

a.feature-card {
  cursor: pointer;
}

.feature-icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--orange-light);
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
  font-size: 1.25rem;
}

.feature-card h3 {
  margin-bottom: 10px;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.925rem;
  line-height: 1.65;
}

/* ── Latest Issues ── */

.latest .section-header {
  margin-bottom: 48px;
}

.issues-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  max-width: 800px;
  margin: 0 auto;
}

.issue-card {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 24px 28px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition), box-shadow var(--transition);
  cursor: pointer;
}

.issue-card:hover {
  border-color: var(--orange);
  box-shadow: 0 4px 16px rgba(255, 109, 0, 0.06);
}

.issue-number {
  font-family: var(--mono);
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--orange);
  background: var(--orange-light);
  padding: 6px 12px;
  border-radius: 6px;
  white-space: nowrap;
}

.issue-content {
  flex: 1;
}

.issue-title {
  font-weight: 700;
  font-size: 1rem;
  margin-bottom: 4px;
}

.issue-meta {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.issue-arrow {
  color: var(--text-muted);
  font-size: 1.2rem;
  transition: transform var(--transition), color var(--transition);
}

.issue-card:hover .issue-arrow {
  transform: translateX(4px);
  color: var(--orange);
}

/* ── CTA Section ── */

.cta-section {
  background: var(--dark);
  color: #fff;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-section::before {
  content: '';
  position: absolute;
  top: -100px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 400px;
  background: radial-gradient(ellipse, rgba(255, 109, 0, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.cta-section h2 {
  position: relative;
  margin-bottom: 16px;
}

.cta-section h2 .accent {
  color: var(--orange);
}

.cta-section p {
  color: rgba(255, 255, 255, 0.6);
  max-width: 480px;
  margin: 0 auto 36px;
  font-size: 1.05rem;
}

.cta-section .hero-form input {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.15);
  color: #fff;
}

.cta-section .hero-form input::placeholder {
  color: rgba(255, 255, 255, 0.35);
}

.cta-section .hero-form input:focus {
  border-color: var(--orange);
}

.cta-section .hero-note {
  color: rgba(255, 255, 255, 0.3);
}

/* ── Footer ── */

footer {
  padding: 64px 0 40px;
  border-top: 1px solid var(--border);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand .nav-logo {
  margin-bottom: 16px;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
  max-width: 280px;
}

.footer-col h4 {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.footer-col a {
  display: block;
  font-size: 0.9rem;
  color: var(--text-secondary);
  padding: 4px 0;
  transition: color var(--transition);
}

.footer-col a:hover {
  color: var(--orange);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer-social {
  display: flex;
  gap: 16px;
}

.footer-social a {
  color: var(--text-muted);
  transition: color var(--transition);
}

.footer-social a:hover {
  color: var(--orange);
}

/* ── Cursor & Interactive States ── */

.nav-logo {
  cursor: pointer;
}

.hero-form input {
  cursor: text;
}

.footer-social a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  transition: color var(--transition), background var(--transition), transform var(--transition);
}

.footer-social a:hover {
  color: var(--orange);
  background: var(--orange-light);
  transform: translateY(-2px);
}

.nav-links a {
  position: relative;
}

.nav-links a:not(.nav-cta)::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--orange);
  border-radius: 1px;
  transition: width var(--transition);
}

.nav-links a:not(.nav-cta):hover::after {
  width: 100%;
}

.footer-col a {
  position: relative;
}

.footer-col a::after {
  content: '';
  position: absolute;
  bottom: 2px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--orange);
  transition: width var(--transition);
}

.footer-col a:hover::after {
  width: 100%;
}

.issue-card:hover .issue-title {
  color: var(--orange);
}

.stat {
  transition: background var(--transition);
}

.stat:hover {
  background: var(--orange-light);
}

.hero-badge {
  cursor: default;
}

.section-label {
  cursor: default;
}

/* Article page styles */
.article-body a {
  color: var(--orange);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition);
}

.article-body a:hover {
  border-bottom-color: var(--orange);
}

/* ── Animations ── */

.fade-up {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── Responsive ── */

@media (max-width: 900px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  section { padding: 72px 0; }
  .hero { padding: 120px 0 72px; }

  .nav-links { display: none; }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(20px);
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid var(--border);
  }
  .nav-toggle { display: block; }

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

  .hero-form {
    flex-direction: column;
  }

  .hero-form input,
  .hero-form button {
    width: 100%;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }

  .issue-card {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}