/* ============================================================
   FOUNDATION — GLOBAL SURFACE / GLASS SYSTEM
   FILE: assets/css/surfaces.css
   Phase 1.4 of the Final Master Roadmap, Stage 1.
   Depends on: tokens.css, buttons.css.
   Owns: every reusable card/panel/surface treatment in the
   project. Glass is one tool among these, never a blanket rule
   — future sections opt into it explicitly, per element.
   ============================================================ */

/* ----------------------------------------------------------
   1. SOLID SURFACE
   Appropriate for: content cards on a light section background,
   forms, anywhere strong readability matters most.
---------------------------------------------------------- */
.surface--solid {
  background-color: var(--color-white);
  border: var(--border-hairline);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-sm);
}

/* ----------------------------------------------------------
   2. TRANSLUCENT GLASS SURFACE
   Appropriate for: panels sitting over a photograph or gradient
   (e.g. a Hero visual card), where depth matters more than
   maximum contrast — always pair with sufficient text contrast.
---------------------------------------------------------- */
.surface--glass {
  position: relative;
  background-color: var(--glass-bg);
  border: var(--border-hairline-light);
  border-radius: var(--radius-card);
  backdrop-filter: blur(var(--glass-blur));
  -webkit-backdrop-filter: blur(var(--glass-blur));
  box-shadow: var(--shadow-md);
}

/* Subtle top-edge reflection highlight, purely decorative */
.surface--glass::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(180deg, var(--glass-highlight), transparent 40%);
  opacity: 0.5;
  pointer-events: none;
  z-index: var(--z-decorative);
}

/* Stronger variant for surfaces that need to sit over busy imagery
   and still read clearly (e.g. a sticky/scrolled navigation state) */
.surface--glass-strong {
  background-color: var(--glass-bg-strong);
  backdrop-filter: blur(var(--glass-blur-strong));
  -webkit-backdrop-filter: blur(var(--glass-blur-strong));
}

/* Fallback for browsers without backdrop-filter support: fall
   back toward a solid-enough background so text stays readable */
@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .surface--glass {
    background-color: rgba(var(--color-navy-rgb), 0.85);
  }
  .surface--glass-strong {
    background-color: rgba(var(--color-navy-rgb), 0.92);
  }
}

/* ----------------------------------------------------------
   3. GRADIENT-LAYERED SURFACE
   Appropriate for: full-bleed section backgrounds that need
   depth without a photograph (e.g. a dark hero background).
---------------------------------------------------------- */
.surface--gradient {
  background:
    radial-gradient(circle at 78% 25%, rgba(var(--color-gold-rgb), 0.14), transparent 28%),
    linear-gradient(120deg, #061a32 0%, var(--color-navy) 52%, #153c62 100%);
  color: var(--color-white);
}

/* ----------------------------------------------------------
   4. PHOTOGRAPHY SURFACE
   Appropriate for: image-backed sections that need a readable
   text layer above them — pairs an image with a controlled
   scrim, never an opaque cover.
---------------------------------------------------------- */
.surface--photography {
  position: relative;
  overflow: hidden;
}

.surface--photography::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(var(--color-navy-rgb), 0.15), rgba(var(--color-navy-rgb), 0.65));
  pointer-events: none;
  z-index: var(--z-decorative);
}

/* ----------------------------------------------------------
   5. ELEVATION MODIFIER (stackable on any surface above)
---------------------------------------------------------- */
.surface--elevated {
  box-shadow: var(--shadow-lg);
}