/* shacengbao — warm sand / terracotta desert theme with arch motifs and strata layers.
   Distinct from Luyin (dark teal), MiDa (light violet), RunYan (warm emerald),
   Cojzq (navy+lime console), Ssyuan (ink+gold serif). */

html {
  scroll-behavior: smooth;
}

body {
  overflow-x: hidden;
}

/* Scroll reveal */
.fade-up {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease-out, transform 0.7s ease-out;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Logo mark: arch-shaped tile with the letter s */
.logo-dune {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 999px 999px 8px 8px;
  background: linear-gradient(160deg, #D5764F, #A84B2B);
  color: #fff;
  font-family: 'Rubik', system-ui, sans-serif;
  font-weight: 700;
  font-size: 1.15rem;
  line-height: 1;
  box-shadow: 0 4px 12px -4px rgba(168, 75, 43, 0.55);
}

/* Letter-spaced eyebrows */
.eyebrow-clay {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: #A84B2B;
}

.eyebrow-sun {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: #DFAF5C;
}

/* Sun disc behind hero */
.sun-disc {
  position: absolute;
  top: 4rem;
  right: 8%;
  width: 17rem;
  height: 17rem;
  border-radius: 9999px;
  background: radial-gradient(circle, rgba(223, 175, 92, 0.5), rgba(223, 175, 92, 0.12) 60%, transparent 72%);
  pointer-events: none;
}

/* Layered strata lines (sand sediment) */
.strata {
  position: absolute;
  left: 0;
  right: 0;
  pointer-events: none;
  background-repeat: repeat-x;
  background-size: 1440px 100%;
}

.strata-hero {
  bottom: 0;
  height: 140px;
  background-image:
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 1440 140'%3E%3Cpath d='M0,140 L0,96 C260,54 520,118 760,86 C1000,54 1240,104 1440,66 L1440,140 Z' fill='%23F7EFE2'/%3E%3C/svg%3E"),
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 1440 140'%3E%3Cpath d='M0,140 L0,116 C300,86 560,132 820,104 C1060,78 1260,118 1440,94 L1440,140 Z' fill='%23EFE2CC'/%3E%3C/svg%3E");
}

/* Arch image frame — signature motif */
.arch-frame {
  border-radius: 9999px 9999px 20px 20px;
  overflow: hidden;
  border: 1px solid #E3D2B4;
  box-shadow: 0 24px 60px -24px rgba(168, 75, 43, 0.35);
  background: #fff;
}

/* Arch icon chips */
.arch-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 3.25rem;
  height: 3.75rem;
  border-radius: 9999px 9999px 12px 12px;
}

/* Strata tiles in About */
.strata-tile {
  border-radius: 14px;
  background: #fff;
  border: 1px solid #EFE2CC;
  padding: 1.25rem 1.25rem 1.1rem;
  position: relative;
  overflow: hidden;
}

.strata-tile::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 6px;
}

.strata-clay::before { background: linear-gradient(90deg, #C25E3A, #ECBFA8); }
.strata-sun::before { background: linear-gradient(90deg, #D9A441, #EBC57E); }
.strata-dune::before { background: linear-gradient(90deg, #4A3628, #8C7A66); }

/* Multi-tone strata rule under case-study headings */
.strata-rule {
  height: 5px;
  border-radius: 3px;
  background: linear-gradient(90deg, #C25E3A 0 33%, #D9A441 33% 66%, #4A3628 66% 100%);
  opacity: 0.55;
}

/* Arc sweep inside flagship card */
.strata-arc {
  position: absolute;
  bottom: -4.5rem;
  right: -3rem;
  width: 15rem;
  height: 15rem;
  border-radius: 9999px;
  background: repeating-radial-gradient(circle at center, rgba(255,255,255,0.14) 0 2px, transparent 2px 14px);
  pointer-events: none;
}

/* Nav */
.nav-text {
  font-size: 0.92rem;
  font-weight: 600;
  color: rgba(51, 38, 27, 0.6);
  transition: color 0.2s;
}

.nav-text:hover {
  color: #A84B2B;
}

#navbar {
  background: transparent;
}

#navbar.scrolled {
  background: rgba(251, 247, 239, 0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: 0 4px 24px rgba(74, 54, 40, 0.1);
  border-bottom: 1px solid #E3D2B4;
}

/* Service cards */
.svc-card {
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.svc-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 18px 40px -18px rgba(74, 54, 40, 0.35);
}

/* Chips */
.chip {
  font-size: 0.7rem;
  font-weight: 600;
  color: #A84B2B;
  background: #FBF7EF;
  border: 1px solid #F6E0D4;
  border-radius: 999px;
  padding: 0.3rem 0.85rem;
}

.chip-on-clay {
  font-size: 0.7rem;
  font-weight: 600;
  color: #FBF0EA;
  background: rgba(255, 255, 255, 0.14);
  border: 1px solid rgba(255, 255, 255, 0.28);
  border-radius: 999px;
  padding: 0.3rem 0.85rem;
}

/* Case study labels */
.cs-label {
  font-size: 0.66rem;
  font-weight: 700;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: #A84B2B;
}

/* Form fields */
.field {
  width: 100%;
  background: rgba(247, 239, 226, 0.06);
  border: 1px solid rgba(227, 210, 180, 0.22);
  border-radius: 0.75rem;
  padding: 0.9rem 1.25rem;
  color: #F7EFE2;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.field::placeholder {
  color: rgba(247, 239, 226, 0.32);
}

.field:focus {
  border-color: transparent;
  box-shadow: 0 0 0 2px rgba(223, 175, 92, 0.55);
}

/* Ambient glow in contact */
.contact-glow {
  position: absolute;
  border-radius: 9999px;
  filter: blur(90px);
  pointer-events: none;
  width: 32rem;
  height: 32rem;
  background: radial-gradient(circle, rgba(194, 94, 58, 0.25), transparent 70%);
  bottom: -12rem;
  left: -10rem;
}

/* Footer column labels */
.footer-label {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: rgba(223, 175, 92, 0.75);
}

/* Buttons */
.btn-primary {
  box-shadow: 0 8px 22px -6px rgba(168, 75, 43, 0.5);
}

.btn-outline {
  box-shadow: 0 4px 14px -6px rgba(168, 75, 43, 0.22);
}

@media (prefers-reduced-motion: reduce) {
  .fade-up { transition: none; opacity: 1; transform: none; }
  html { scroll-behavior: auto; }
}