/* Design System Variables */
:root {
  --primary: #475569;
  --secondary: #f8fafc;
  --accent: #3b82f6;
  --text: #0f172a;
  --bg: #ffffff;
}

/* Base Styles & Typography */
body {
  background: var(--bg);
  color: var(--text);
  font-size: clamp(14px, 1.2vw, 16px);
}

section {
  padding: 48px 16px;
}

@media (min-width: 768px) {
  section {
    padding: 64px 16px;
  }
}

.card {
  border-radius: 20px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
}

h1 {
  font-weight: 800;
  line-height: 1.1;
  font-size: clamp(20px, 4vw, 30px);
}

h2 {
  font-size: clamp(22px, 5vw, 36px);
}

.btn {
  border-radius: 16px;
  font-weight: 700;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
  min-height: 44px;
}

/* Screen Reader Only Utility */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* CSS-Only Gallery Styles */
.gallery-main {
  position: relative;
  width: 100%;
  padding-bottom: 100%; /* Forces square ratio */
  overflow: hidden;
}

.slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  z-index: 1;
  transition: opacity 0.3s ease-in-out;
}

.slide img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.thumbnails {
  display: flex;
  gap: 12px;
  margin-top: 16px;
  justify-content: center;
}

.thumbnails label {
  width: 64px;
  height: 64px;
  border: 2px solid transparent;
  border-radius: 8px;
  overflow: hidden;
  cursor: pointer;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.thumbnails label:hover {
  transform: scale(1.05);
}

.thumbnails label img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* Gallery Radio Behavior */
#img-1:checked ~ .gallery-main .slide-1,
#img-2:checked ~ .gallery-main .slide-2,
#img-3:checked ~ .gallery-main .slide-3,
#img-4:checked ~ .gallery-main .slide-4 {
  opacity: 1;
  z-index: 10;
}

#img-1:checked ~ .thumbnails label[for="img-1"],
#img-2:checked ~ .thumbnails label[for="img-2"],
#img-3:checked ~ .thumbnails label[for="img-3"],
#img-4:checked ~ .thumbnails label[for="img-4"] {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}