:root {
  --ink: #0f172a;
  --muted: #475569;
  --line: #d9dde8;
  --accent: #1b3a73;
  --surface: #ffffff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Times New Roman", "Times", "Georgia", serif;
  color: var(--ink);
  background: #ffffff;
}

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

.page-wrap {
  max-width: 1080px;
  margin: 0 auto;
  padding: 2rem 1rem 3rem;
}

.top-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.btn-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 0.95rem;
  border: 1px solid var(--line);
  border-radius: 8px;
  text-decoration: none;
  color: var(--ink);
  background: var(--surface);
  font-size: 0.95rem;
}

.btn-link.active {
  background: var(--accent);
  color: #ffffff;
  border-color: var(--accent);
}

h1 {
  margin: 0 0 0.5rem;
  font-size: clamp(1.7rem, 3.1vw, 2.2rem);
}

.subtitle {
  margin: 0 0 1.5rem;
  color: var(--muted);
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1rem;
}

.gallery-card {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1rem;
}

.gallery-card h2 {
  margin-top: 0;
}

.widget {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1rem;
}

.control-row {
  display: grid;
  gap: 0.85rem;
  margin-bottom: 1rem;
}

.control-group {
  display: grid;
  gap: 0.35rem;
}

.control-group label {
  font-size: 0.92rem;
  color: var(--muted);
}

.control-group input[type="range"] {
  width: 100%;
}

.preview-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  align-items: start;
}

.panel {
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
  background: #ffffff;
}

.panel-label {
  padding: 0.45rem 0.7rem;
  border-bottom: 1px solid var(--line);
  font-size: 0.84rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.panel img {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: contain;
  object-position: center;
  display: block;
  background: #ffffff;
}

@media (min-width: 1440px) {
  .page-wrap {
    max-width: 1320px;
  }
}

@media (max-width: 900px) {
  .preview-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 640px) {
  .page-wrap {
    padding: 1.2rem 0.75rem 2rem;
  }

  .top-nav {
    display: grid;
    grid-template-columns: 1fr;
  }

  .btn-link {
    width: 100%;
  }

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

  .panel-label {
    font-size: 0.78rem;
    letter-spacing: 0.06em;
  }

  .widget {
    padding: 0.75rem;
  }
}