:root {
    --bg: #f7f9fb;
    --surface: #ffffff;
    --ink: #14213d;
    --muted: #5f6c7b;
    --line: #dfe7ef;
    --primary: #0f766e;
    --primary-dark: #115e59;
    --accent: #f59e0b;
    --soft: #e7f6f4;
    --shadow: 0 24px 70px rgba(20, 33, 61, 0.12);
  }
  
  * {
    box-sizing: border-box;
  }
  
  html {
    scroll-behavior: smooth;
  }
  
  body {
    margin: 0;
    font-family: "Inter", Arial, sans-serif;
    color: var(--ink);
    background: var(--bg);
    line-height: 1.6;
  }
  
  a {
    color: inherit;
    text-decoration: none;
  }
  
  .site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(247, 249, 251, 0.9);
    border-bottom: 1px solid rgba(223, 231, 239, 0.8);
    backdrop-filter: blur(16px);
  }
  
  .nav {
    width: min(1120px, calc(100% - 32px));
    min-height: 72px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
  }
  
  .brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: 0;
  }
  
  .brand-mark {
    display: grid;
    width: 42px;
    height: 42px;
    place-items: center;
    color: #ffffff;
    background: var(--ink);
    border-radius: 8px;
    font-size: 0.9rem;
  }
  
  .nav-links {
    display: flex;
    align-items: center;
    gap: 18px;
    color: var(--muted);
    font-size: 0.95rem;
    font-weight: 600;
  }
  
  .nav-links a:hover,
  .nav-links a:focus {
    color: var(--primary);
  }
  
  .nav-toggle {
    display: none;
    width: 44px;
    height: 44px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--surface);
    cursor: pointer;
  }
  
  .nav-toggle span {
    display: block;
    width: 20px;
    height: 2px;
    margin: 4px auto;
    background: var(--ink);
    border-radius: 999px;
  }
  
  .hero {
    width: min(1120px, calc(100% - 32px));
    min-height: calc(100vh - 72px);
    margin: 0 auto;
    padding: 80px 0 56px;
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(320px, 0.95fr);
    align-items: center;
    gap: 56px;
  }
  
  .hero-content {
    max-width: 670px;
  }
  
  .eyebrow {
    margin: 0 0 12px;
    color: var(--primary);
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.12em;
    text-transform: uppercase;
  }
  
  h1,
  h2,
  h3,
  p {
    margin-top: 0;
  }
  
  h1 {
    margin-bottom: 20px;
    font-size: clamp(2.65rem, 8vw, 5.6rem);
    line-height: 0.96;
    letter-spacing: 0;
  }
  
  h2 {
    margin-bottom: 0;
    font-size: clamp(1.85rem, 4vw, 3rem);
    line-height: 1.1;
    letter-spacing: 0;
  }
  
  h3 {
    margin-bottom: 8px;
    font-size: 1.05rem;
  }
  
  .hero-copy {
    max-width: 620px;
    margin-bottom: 30px;
    color: var(--muted);
    font-size: 1.12rem;
  }
  
  .hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
  }
  
  .button {
    display: inline-flex;
    min-height: 48px;
    align-items: center;
    justify-content: center;
    padding: 0 22px;
    border-radius: 8px;
    font-weight: 800;
    transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease, border-color 180ms ease;
  }
  
  .button:hover,
  .button:focus {
    transform: translateY(-2px);
  }
  
  .button.primary {
    color: #ffffff;
    background: var(--primary);
    box-shadow: 0 16px 34px rgba(15, 118, 110, 0.24);
  }
  
  .button.primary:hover,
  .button.primary:focus {
    background: var(--primary-dark);
  }
  
  .button.secondary {
    color: var(--ink);
    background: var(--surface);
    border: 1px solid var(--line);
  }
  
  .hero-panel {
    display: flex;
    justify-content: center;
  }
  
  .camera-card {
    width: min(100%, 430px);
    padding: 18px;
    border: 1px solid rgba(223, 231, 239, 0.95);
    border-radius: 8px;
    background: var(--surface);
    box-shadow: var(--shadow);
  }
  
  .camera-topbar {
    display: flex;
    gap: 8px;
    margin-bottom: 18px;
  }
  
  .camera-topbar span {
    width: 11px;
    height: 11px;
    border-radius: 50%;
    background: var(--line);
  }
  
  .camera-topbar span:first-child {
    background: #ef4444;
  }
  
  .camera-topbar span:nth-child(2) {
    background: var(--accent);
  }
  
  .camera-topbar span:last-child {
    background: #22c55e;
  }
  
  .scan-window {
    position: relative;
    display: grid;
    min-height: 320px;
    place-items: center;
    overflow: hidden;
    border-radius: 8px;
    background:
      linear-gradient(rgba(20, 33, 61, 0.08) 1px, transparent 1px),
      linear-gradient(90deg, rgba(20, 33, 61, 0.08) 1px, transparent 1px),
      #eaf4f1;
    background-size: 30px 30px;
  }
  
  .face-outline {
    position: relative;
    width: 170px;
    height: 220px;
    border: 4px solid var(--primary);
    border-radius: 48% 48% 42% 42%;
    box-shadow: 0 0 0 14px rgba(15, 118, 110, 0.08);
  }
  
  .face-outline::before,
  .face-outline::after {
    content: "";
    position: absolute;
    top: 78px;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--ink);
  }
  
  .face-outline::before {
    left: 42px;
  }
  
  .face-outline::after {
    right: 42px;
  }
  
  .scan-line {
    position: absolute;
    left: -24px;
    right: -24px;
    top: 34px;
    height: 3px;
    background: var(--accent);
    box-shadow: 0 0 18px rgba(245, 158, 11, 0.7);
    animation: scan 2.6s ease-in-out infinite;
  }
  
  .attendance-log {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    margin-top: 16px;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: 8px;
    color: var(--muted);
    font-size: 0.9rem;
  }
  
  .attendance-log div {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--ink);
  }
  
  .status-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #22c55e;
    box-shadow: 0 0 0 5px rgba(34, 197, 94, 0.16);
  }
  
  .section {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto;
    padding: 86px 0;
  }
  
  .section-heading {
    max-width: 720px;
    margin-bottom: 34px;
  }
  
  .grid {
    display: grid;
    gap: 18px;
  }
  
  .feature-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  
  .card,
  .improvement-list article {
    padding: 24px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--surface);
    transition: transform 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
  }
  
  .card:hover,
  .improvement-list article:hover {
    transform: translateY(-4px);
    border-color: rgba(15, 118, 110, 0.32);
    box-shadow: 0 18px 44px rgba(20, 33, 61, 0.1);
  }
  
  .card p,
  .timeline-item p,
  .improvement-list p {
    margin-bottom: 0;
    color: var(--muted);
  }
  
  .card-icon {
    display: inline-flex;
    margin-bottom: 24px;
    color: var(--primary);
    font-weight: 800;
  }
  
  .split-section {
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
  }
  
  .timeline {
    display: grid;
    gap: 16px;
  }
  
  .timeline-item {
    display: grid;
    grid-template-columns: 52px 1fr;
    gap: 18px;
    padding: 22px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--surface);
  }
  
  .timeline-item > span {
    display: grid;
    width: 52px;
    height: 52px;
    place-items: center;
    color: #ffffff;
    background: var(--ink);
    border-radius: 8px;
    font-weight: 800;
  }
  
  .screenshots-section {
    border-bottom: 1px solid var(--line);
  }
  
  .screenshots-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    align-items: stretch;
    gap: 22px;
  }
  
  .screenshot-card {
    display: flex;
    min-height: 100%;
    flex-direction: column;
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--surface);
    box-shadow: 0 16px 44px rgba(20, 33, 61, 0.08);
    transition: transform 200ms ease, border-color 200ms ease, box-shadow 200ms ease;
  }
  
  .screenshot-card:hover {
    transform: translateY(-6px);
    border-color: rgba(15, 118, 110, 0.34);
    box-shadow: 0 26px 70px rgba(20, 33, 61, 0.14);
  }
  
  .screenshot-media {
    aspect-ratio: 16 / 10;
    overflow: hidden;
    border-bottom: 1px solid var(--line);
    background: #edf4f7;
  }
  
  .screenshot-media img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: left top;
    transition: transform 260ms ease;
  }
  
  .screenshot-card:hover .screenshot-media img {
    transform: scale(1.03);
  }
  
  .csv-media {
    display: grid;
    place-items: center;
    padding: 18px;
    background:
      linear-gradient(135deg, rgba(20, 33, 61, 0.96), rgba(15, 118, 110, 0.82)),
      #14213d;
  }
  
  .csv-media img {
    height: auto;
    object-fit: contain;
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 8px;
    box-shadow: 0 16px 38px rgba(0, 0, 0, 0.22);
  }
  
  .screenshot-content {
    display: flex;
    flex: 1;
    flex-direction: column;
    min-height: 221px;
    padding: 24px;
  }
  
  .screenshot-content p {
    flex: 1;
    margin-bottom: 0;
    color: var(--muted);
  }
  
  .screenshot-tag {
    display: inline-flex;
    margin-bottom: 12px;
    padding: 6px 10px;
    border-radius: 8px;
    color: var(--primary-dark);
    background: var(--soft);
    font-size: 0.78rem;
    font-weight: 800;
  }
  
  .tech-list {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
  }
  
  .tech-list span {
    padding: 12px 16px;
    border: 1px solid rgba(15, 118, 110, 0.2);
    border-radius: 8px;
    color: var(--primary-dark);
    background: var(--soft);
    font-weight: 800;
  }
  
  .future-section {
    padding-top: 48px;
  }
  
  .improvement-list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
  }
  
  .footer {
    padding: 28px 16px;
    color: var(--muted);
    text-align: center;
    background: var(--surface);
    border-top: 1px solid var(--line);
  }
  
  .footer p {
    margin: 0;
  }
  
  @keyframes scan {
    0%,
    100% {
      transform: translateY(0);
    }
  
    50% {
      transform: translateY(145px);
    }
  }
  
  @media (max-width: 900px) {
    .hero {
      min-height: auto;
      grid-template-columns: 1fr;
      padding-top: 56px;
    }
  
    .hero-panel {
      justify-content: flex-start;
    }
  
    .feature-grid {
      grid-template-columns: repeat(2, minmax(0, 1fr));
    }
  
    .screenshots-grid {
      grid-template-columns: 1fr;
    }
  }
  
  @media (max-width: 720px) {
    .nav {
      min-height: 64px;
    }
  
    .nav-toggle {
      display: block;
    }
  
    .nav-links {
      position: absolute;
      left: 16px;
      right: 16px;
      top: 72px;
      display: none;
      flex-direction: column;
      align-items: stretch;
      gap: 0;
      padding: 8px;
      border: 1px solid var(--line);
      border-radius: 8px;
      background: var(--surface);
      box-shadow: var(--shadow);
    }
  
    .nav-links.open {
      display: flex;
    }
  
    .nav-links a {
      padding: 12px;
    }
  
    .hero {
      width: min(100% - 24px, 1120px);
      padding: 42px 0 34px;
      gap: 32px;
    }
  
    .section {
      width: min(100% - 24px, 1120px);
      padding: 60px 0;
    }
  
    .hero-actions,
    .attendance-log {
      align-items: stretch;
      flex-direction: column;
    }
  
    .button {
      width: 100%;
    }
  
    .feature-grid,
    .screenshots-grid,
    .improvement-list {
      grid-template-columns: 1fr;
    }
  
    .timeline-item {
      grid-template-columns: 1fr;
    }
  
    .scan-window {
      min-height: 260px;
    }
  
    .face-outline {
      transform: scale(0.85);
    }
  
    .screenshot-content {
      padding: 20px;
    }
  }
  
  @media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
      scroll-behavior: auto !important;
      animation-duration: 0.01ms !important;
      animation-iteration-count: 1 !important;
      transition-duration: 0.01ms !important;
    }
  }