/* ============================================
   glass.css — Translucent "liquid glass" surfaces

   backdrop-filter is limited to three components:
   the header, the mobile nav panel, and the contact form.
   Every other surface uses a semi-transparent fill.
   ============================================ */

/* Glass design tokens — Light theme */
:root {
  --glass-bg: rgba(255, 255, 255, 0.50);
  --glass-bg-hover: rgba(255, 255, 255, 0.55);
  --glass-bg-strong: rgba(255, 255, 255, 0.50);
  --glass-border: rgba(255, 255, 255, 0.5);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.06), 0 2px 8px rgba(0, 0, 0, 0.04);
  --glass-shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.1), 0 4px 12px rgba(0, 0, 0, 0.05);
  --glass-inset-highlight: inset 0 1px 0 rgba(255, 255, 255, 0.5);
  --glass-blur: blur(16px) saturate(150%);
  --glass-blur-medium: blur(14px) saturate(145%);
  --glass-red-glow: rgba(198, 40, 40, 0.25);
  --glass-red-glow-hover: rgba(198, 40, 40, 0.35);
  --glass-bg-solid: #f6f6f4;
  --glass-bg-strong-solid: #ffffff;
}

/* Glass design tokens — Dark theme */
:root[data-theme="dark"] {
  --glass-bg: rgba(0, 0, 0, 0.50);
  --glass-bg-hover: rgba(0, 0, 0, 0.55);
  --glass-bg-strong: rgba(0, 0, 0, 0.50);
  --glass-border: rgba(255, 255, 255, 0.12);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.3), 0 2px 8px rgba(0, 0, 0, 0.2);
  --glass-shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.4), 0 4px 12px rgba(0, 0, 0, 0.25);
  --glass-inset-highlight: inset 0 1px 0 rgba(255, 255, 255, 0.06);
  --glass-red-glow: rgba(198, 40, 40, 0.35);
  --glass-red-glow-hover: rgba(198, 40, 40, 0.45);
  --glass-bg-solid: #151719;
  --glass-bg-strong-solid: #1d2023;
}

/* 1. GLASS HEADER */
.site-header {
  background: transparent;
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  box-shadow: none;
  transform: translateZ(0);
  border-radius: 12px;
  margin: var(--space-xs);
  width: calc(100% - 16px);
  transition: background-color var(--duration-medium) ease, box-shadow var(--duration-medium) ease;
}
.site-header.is-scrolled {
  background: var(--glass-bg-strong);
  box-shadow: var(--glass-inset-highlight), 0 1px 0 var(--header-border);
}

/* 2. GLASS NAVIGATION */
.primary-nav > a:not(.nav-cta) {
  position: relative;
  padding: var(--space-xs) 14px;
  border-radius: 999px;
  transition: color var(--duration-fast), background var(--duration-fast), box-shadow var(--duration-fast);
}
.primary-nav > a:not(.nav-cta):hover {
  background: var(--glass-bg);
  box-shadow: var(--glass-inset-highlight);
}

/* Mobile nav — glass dropdown panel */
@media (max-width: 900px) {
  .js .primary-nav {
    background: var(--glass-bg-strong);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    box-shadow: var(--glass-inset-highlight), var(--glass-shadow);
    border-radius: 12px;
    margin: 0 var(--space-xs);
  }
}

/* 3. SERVICE CARDS — translucent fill only (no backdrop-filter) */
.service-card {
  background: var(--glass-bg);
  box-shadow: var(--glass-inset-highlight);
  transition: background var(--duration-fast) ease, box-shadow var(--duration-fast) ease, transform var(--duration-fast) ease;
}
.service-card:hover {
  background: var(--glass-bg-hover);
  box-shadow: var(--glass-inset-highlight), var(--glass-shadow-hover);
}

/* 4. GLASS CONTACT FORM */
.contact-form {
  position: relative;
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur-medium);
  -webkit-backdrop-filter: var(--glass-blur-medium);
  box-shadow: var(--glass-inset-highlight), var(--glass-shadow);
  transform: translateZ(0);
}

/* Form inputs inherit the form's blur */
.contact-form input,
.contact-form textarea {
  background: var(--glass-bg);
  box-shadow: var(--glass-inset-highlight);
  transition: background var(--duration-fast), box-shadow var(--duration-fast);
}
.contact-form input:focus,
.contact-form textarea:focus {
  background: var(--glass-bg-hover);
  box-shadow: var(--glass-inset-highlight), 0 0 0 1px var(--red);
}

/* 5. BUTTONS */
.button-red,
.nav-cta {
  background: linear-gradient(180deg, var(--red-bright) 0%, var(--red) 50%, #a9171f 100%);
  box-shadow: var(--glass-inset-highlight), 0 4px 16px var(--glass-red-glow);
  transition: background var(--duration-fast), box-shadow var(--duration-fast), transform var(--duration-fast);
}
.button-red:hover,
.nav-cta:hover {
  background: linear-gradient(180deg, var(--red) 0%, #a9171f 100%);
  box-shadow: var(--glass-inset-highlight), 0 6px 20px var(--glass-red-glow-hover);
}
.button-outline {
  transition: background var(--duration-fast), border-color var(--duration-fast), color var(--duration-fast), box-shadow var(--duration-fast), transform var(--duration-fast);
}
.button-outline:hover {
  background: var(--glass-bg);
  box-shadow: var(--glass-inset-highlight);
}

/* 6. THEME TOGGLE — translucent fill only */
[data-theme-toggle] {
  background: var(--glass-bg);
  border-color: var(--glass-border);
  box-shadow: var(--glass-inset-highlight), var(--glass-shadow);
  transition: border-color var(--duration-fast), background-color var(--duration-fast), box-shadow var(--duration-fast), transform var(--duration-fast);
}
[data-theme-toggle]:hover {
  background: var(--glass-bg-hover);
  border-color: var(--accent-text);
  box-shadow: var(--glass-inset-highlight), var(--glass-shadow-hover);
}
[data-theme-toggle] .theme-toggle__icon {
  filter: drop-shadow(0 0 6px var(--accent-text));
}

/* 7. FOOTER — translucent fill only */
.site-footer {
  background: var(--glass-bg);
}
.footer-bottom {
  box-shadow: var(--glass-inset-highlight);
}

/* 8. DEPTH & LAYERING — top-edge highlight for glass panels */
.service-card::before,
.contact-form::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--glass-border), transparent);
  pointer-events: none;
}

/* 9. PERFORMANCE — solid fallbacks when backdrop-filter is unsupported */
@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .site-header {
    background: var(--glass-bg-strong-solid);
  }
  @media (max-width: 900px) {
    .js .primary-nav {
      background: var(--glass-bg-strong-solid);
    }
  }
  .contact-form {
    background: var(--glass-bg-solid);
  }
  .contact-form input,
  .contact-form textarea {
    background: var(--glass-bg-solid);
  }
  .contact-form input:focus,
  .contact-form textarea:focus {
    background: var(--glass-bg-strong-solid);
  }
}