/* Design System Custom Properties */
:root {
  --primary: #c2410c;
  --secondary: #fff7ed;
  --accent: #0284c7;
  --text: #431407;
  --bg: #fef9f5;
}

/* Base resets & typography */
body {
  background: #fff;
  color: #111;
  font-family: 'Inter', sans-serif;
  font-size: clamp(14px, 4vw, 16px);
}

section {
  padding: 64px 16px;
}

.card {
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  box-shadow: none;
}

.btn {
  border-radius: 6px;
  font-weight: 600;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease-in-out;
}

h1, h2 {
  font-weight: 700;
}

h1 {
  font-size: clamp(22px, 5vw, 36px);
}

/* Screen reader only utility (strictly mandatory for radio gallery) */
.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;
}

/* Gallery main container */
.gallery-main {
  position: relative;
  width: 100%;
  padding-bottom: 100%; /* Strict rule: height set via padding-bottom */
  overflow: hidden;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  background-color: #f9fafb;
}

/* Slides layouts */
.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: contain;
}

/* Active slide display rules */
#img-1:checked ~ .gallery-main .slide-1 { opacity: 1; z-index: 10; }
#img-2:checked ~ .gallery-main .slide-2 { opacity: 1; z-index: 10; }
#img-3:checked ~ .gallery-main .slide-3 { opacity: 1; z-index: 10; }
#img-4:checked ~ .gallery-main .slide-4 { opacity: 1; z-index: 10; }

/* Thumbnails navigation grid */
.thumbnails {
  display: flex;
  gap: 12px;
  margin-top: 16px;
}

.thumbnails label {
  cursor: pointer;
  border: 2px solid #e5e7eb;
  border-radius: 6px;
  overflow: hidden;
  aspect-ratio: 1 / 1;
  transition: border-color 0.2s ease-in-out;
  background-color: #f9fafb;
}

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

/* Active thumbnail visual feedback */
#img-1:checked ~ .thumbnails label[for="img-1"] { border-color: var(--primary); }
#img-2:checked ~ .thumbnails label[for="img-2"] { border-color: var(--primary); }
#img-3:checked ~ .thumbnails label[for="img-3"] { border-color: var(--primary); }
#img-4:checked ~ .thumbnails label[for="img-4"] { border-color: var(--primary); }