/* ===========================
   :root - Colors & variables
   =========================== */
   :root {
    color-scheme: light dark;
  
    --bg: #050816;
    --bg-elevated: #0b1020;
    --bg-soft: #111827;
  
    --text: #e5e7eb;
    --text-soft: #9ca3af;
  
    --accent: #38bdf8;
    --accent-strong: #0ea5e9;
  
    --radius-lg: 18px;
    --radius-md: 12px;
  
    --transition-fast: 180ms ease-out;
    --transition-med: 280ms ease-out;
    --transition-slow: 400ms ease-out;
  }
  
  /* ===========================
     Base Reset
     =========================== */
  *,
  *::before,
  *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
  }
  
  html {
    scroll-behavior: smooth;
    overflow-x: hidden;
  }
  
  body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: radial-gradient(circle at top, #0b1120 0, #020617 55%, #000 100%);
    color: var(--text);
    line-height: 1.8;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
  }
  
  body.locked {
    overflow: hidden;       /* hide both vertical & horizontal scroll */
    position: fixed;        /* lock body in place */
    width: 100%;            /* prevent layout shift */
  }

  .page {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 16px 64px;
  }
  
  @media (min-width: 960px) {
    .page {
      padding: 0 24px 80px;
    }
  }
  
  /* ===========================
     Scroll animations (fade only)
     =========================== */
  [data-animate] {
    opacity: 1;
    transform: none;
    transition: opacity 800ms ease-out, transform 800ms ease-out;
    will-change: opacity, transform;
  }
  
  [data-animate]:not(.is-visible) {
    opacity: 0;
    transform: translateY(50px);
  }
  
  @media (prefers-reduced-motion: reduce) {
    [data-animate],
    [data-animate]:not(.is-visible) {
      opacity: 1 !important;
      transform: none !important;
      transition: none !important;
    }
  }
  
  /* ===========================
     Typography
     =========================== */
  h1, h2, h3, h4, h5, h6 {
    color: var(--text);
    line-height: 1.3;
  }
  
  h1 { font-size: 2.75rem; margin-bottom: 20px; scroll-margin-top: 25vh;}
  h2 { font-size: 2rem; margin-bottom: 18px; scroll-margin-top: 25vh;}
  h3 { font-size: 1.5rem; margin-bottom: 16px; scroll-margin-top: 25vh;}
  
  p {
    margin-bottom: 20px;
    color: var(--text-soft);
    line-height: 1.85;
  }
  
  .emphasis {
    font-weight: 600;
    color: var(--text);
    transition: color var(--transition-fast), transform var(--transition-fast);
  }
  
  .emphasis:hover {
    color: var(--accent);
    transform: scale(1.02);
  }
  
  .example-word {
    font-weight: 600;
    color: var(--accent);
    transition: color var(--transition-fast), transform var(--transition-fast);
  }
  
  .example-word:hover {
    color: var(--accent-strong);
    transform: scale(1.03);
  }
  
  /* ===========================
     Section layout
     =========================== */
  section {
    margin-bottom: 80px;
    padding-top: 40px;
    padding-bottom: 40px;
  }
  
  @media (min-width: 960px) {
    section {
      margin-bottom: 100px;
      padding-top: 60px;
      padding-bottom: 60px;
    }
  }
  
  .section-content {
    max-width: 680px;
    margin-left: auto;
    margin-right: auto;
    font-size: 1rem;
  }
  
  .section-align-left .section-content {
    text-align: left;
  }
  
  .section-align-right .section-content {
    text-align: right;
  }
  
  .section-align-center .section-content {
    text-align: center;
  }
  
  /* ===========================
     Hero
     =========================== */
  .hero-section {
    text-align: center;
    padding: 60px 16px 60px;
  }
  
  .hero-title {
    font-size: 2.75rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--accent), #60a5fa);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 20px;
  }
  
  .hero-subtitle {
    font-size: 1.1rem;
    color: var(--text-soft);
  }
  
  /* ===========================
     Split sections
     =========================== */
  .section-split {
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;
    align-items: start;
  }
  
  @media (min-width: 800px) {
    .section-split {
      grid-template-columns: 1fr 1fr;
    }
  
    .section-split-reverse {
      direction: rtl;
    }
  
    .section-split-reverse .split-text {
      direction: ltr;
    }
  }
  
  .split-text {
    min-width: 0;
  }
  
  .split-visual {
    min-width: 0;
  }
  
  /* ===========================
     Cards and compare
     =========================== */
  .compare-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-top: 24px;
  }
  
  @media (max-width: 600px) {
    .compare-row {
      grid-template-columns: 1fr;
    }
  }
  
  .compare-card {
    background: rgba(15, 23, 42, 0.6);
    border-radius: var(--radius-lg);
    padding: 28px 24px;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
  }
  
  .compare-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 32px rgba(15, 23, 42, 0.8);
  }
  
  .compare-card-label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--accent);
    margin-bottom: 12px;
  }
  
  /* ===========================
     Callouts
     =========================== */
  .callout-block {
    background: rgba(56, 189, 248, 0.08);
    border-radius: var(--radius-md);
    padding: 24px 28px;
    margin-top: 24px;
  }
  
  .callout-block p {
    margin-bottom: 0;
  }
  
  /* ===========================
     Footer
     =========================== */
  .site-footer {
    margin-top: 80px;
    padding-top: 32px;
    border-top: 1px solid rgba(30, 64, 175, 0.3);
    font-size: 0.85rem;
    color: var(--text-soft);
    text-align: center;
  }