:root {
  --primary: #0e7490;
  --secondary: #cffafe;
  --accent: #10b981;
  --text: #083344;
  --bg: #f0ffff;
}

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background-color: #f8fafc;
  color: #1e293b;
  font-size: clamp(14px, 4vw, 16px);
}

.main-title {
  font-size: clamp(22px, 5vw, 36px);
  color: #0f172a;
}

header {
  border-bottom: 3px solid var(--primary);
}

.card {
  background: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: 8px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.btn {
  border-radius: 6px;
  font-weight: 600;
  min-height: 44px;
}

.cta-button {
  background-color: var(--primary);
  color: #ffffff !important;
  text-decoration: none;
  transition: background-color 0.2s ease, transform 0.1s ease;
}

.cta-button:hover {
  background-color: #155e75;
}

/* Strict Accessibility Hidden inputs */
.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;
}

/* Pure CSS Gallery */
.gallery-container {
  position: relative;
  width: 100%;
}

.gallery-main {
  position: relative;
  width: 100%;
  padding-bottom: 100%;
  overflow: hidden;
}

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

/* Slides switching */
#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;
}

/* Thumbnail highlighting */
#img-1:checked ~ .thumbnails label[for="img-1"] {
  border-color: var(--primary);
  outline: 2px solid var(--primary);
}

#img-2:checked ~ .thumbnails label[for="img-2"] {
  border-color: var(--primary);
  outline: 2px solid var(--primary);
}

#img-3:checked ~ .thumbnails label[for="img-3"] {
  border-color: var(--primary);
  outline: 2px solid var(--primary);
}

#img-4:checked ~ .thumbnails label[for="img-4"] {
  border-color: var(--primary);
  outline: 2px solid var(--primary);
}

img {
  max-width: 100%;
  height: auto;
}