/* ═══════════════════════════════════════════════════════════════
   Liquid Glass Core - 4-layer physically accurate material
   Usage:
     <div class="liquid-glass [lg-macro]">
       <div class="liquid-glass-effect" />
       <div class="liquid-glass-tint" />
       <div class="liquid-glass-shine" />
       <div class="liquid-glass-content">{content}</div>
     </div>
   ═══════════════════════════════════════════════════════════════ */

:root {
  /* Apple canonical motion curves */
  --ease-apple-out: cubic-bezier(0.32, 0.72, 0, 1);
  --ease-apple-morph: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-apple-liquid: cubic-bezier(0.3, 0, 0, 1.3);
  --ease-apple-magnetic: cubic-bezier(0.34, 1.56, 0.64, 1);
}

.liquid-glass {
  position: relative;
  overflow: hidden;
  border-radius: 22px; /* iOS squircle */
  isolation: isolate;
  /* Perf: skip rendering off-screen glass entirely */
  content-visibility: auto;
  contain-intrinsic-size: auto 240px;
  contain: layout paint;
  box-shadow:
    0 0 0 0.5px rgba(255, 255, 255, 0.06),
    0 8px 24px -8px rgba(0, 0, 0, 0.4),
    0 2px 6px -2px rgba(0, 0, 0, 0.3);
  /* box-shadow only — nothing transforms on hover, and dropping `transform`
     here keeps a timed ease from perpetually chasing the per-frame velocity
     squash transform (--sv) on macro cards. Visually identical. */
  transition: box-shadow 0.25s var(--ease-apple-out);
}

a.liquid-glass:hover,
.liquid-glass:hover {
  box-shadow:
    0 0 0 0.5px rgba(255, 255, 255, 0.1),
    0 12px 32px -8px rgba(0, 0, 0, 0.5),
    0 4px 10px -2px rgba(0, 0, 0, 0.35);
}

/* Layer 0: backdrop refraction (all surfaces get SVG displacement) */
.liquid-glass-effect {
  position: absolute;
  z-index: 0;
  inset: 0;
  overflow: hidden;
  backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04) url(#lg-refract-sm);
  -webkit-backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
}

/* Macros use the larger-scale displacement filter */
.lg-macro > .liquid-glass-effect {
  backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04) url(#lg-refract);
  -webkit-backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
}

html:not(.dark) .liquid-glass-effect {
  backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04) url(#lg-refract-sm);
  -webkit-backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
}
html:not(.dark) .lg-macro > .liquid-glass-effect {
  backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04) url(#lg-refract);
  -webkit-backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
}

/* Opt-in perf lever (v1.1.0) — blur-only inner cards.
   The default keeps url(#lg-refract-sm) on inner cards (unchanged look).
   For consumers who want lighter scroll cost, set html.lg-blur-only (global)
   or add .lg-blur-only to an individual .liquid-glass: its inner-card effect
   drops the SVG displacement and runs blur-only. .lg-macro surfaces keep their
   #lg-refract displacement either way. Purely additive — nothing changes unless
   you opt in. */
html.lg-blur-only .liquid-glass:not(.lg-macro) > .liquid-glass-effect,
.liquid-glass.lg-blur-only:not(.lg-macro) > .liquid-glass-effect {
  backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
  -webkit-backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
}

/* Layer 1: base tint - VISIBLE color so glass shows on pure black */
.liquid-glass-tint {
  position: absolute;
  z-index: 1;
  inset: 0;
  pointer-events: none;
  background: rgba(28, 28, 32, 0.30);
}
.lg-macro > .liquid-glass-tint {
  background: rgba(20, 20, 24, 0.30);
}
html:not(.dark) .liquid-glass-tint {
  background: rgba(255, 255, 255, 0.40);
}
html:not(.dark) .lg-macro > .liquid-glass-tint {
  background: rgba(255, 255, 255, 0.40);
}

/* Layer 2: inset rim highlights - the "lit bezel" (1:2 ratio = convex) */
.liquid-glass-shine {
  position: absolute;
  z-index: 2;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.06),
    inset 0 0 6px 0 rgba(255, 255, 255, 0.04),
    inset 0 2px 4px -2px rgba(255, 255, 255, 0.18),
    inset 0 -2px 4px -2px rgba(0, 0, 0, 0.25);
}
html:not(.dark) .liquid-glass-shine {
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.6),
    inset 0 0 6px 0 rgba(255, 255, 255, 0.3),
    inset 0 2px 4px -2px rgba(255, 255, 255, 0.9),
    inset 0 -2px 4px -2px rgba(0, 0, 0, 0.06);
}
.lg-macro > .liquid-glass-shine {
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.08),
    inset 0 0 8px 0 rgba(255, 255, 255, 0.05),
    inset 0 3px 6px -3px rgba(255, 255, 255, 0.22),
    inset 0 -3px 6px -3px rgba(0, 0, 0, 0.3);
}
html:not(.dark) .lg-macro > .liquid-glass-shine {
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.7),
    inset 0 0 8px 0 rgba(255, 255, 255, 0.35),
    inset 0 3px 6px -3px rgba(255, 255, 255, 0.95),
    inset 0 -3px 6px -3px rgba(0, 0, 0, 0.08);
}

/* Layer 3: content sits above all material layers */
.liquid-glass-content {
  position: relative;
  z-index: 3;
}

/* Noise grain (::before) - static, soft-light blend */
.liquid-glass::before {
  content: '';
  position: absolute;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  border-radius: inherit;
  opacity: 0.035;
  mix-blend-mode: soft-light;
  background-image: url("data:image/svg+xml;utf8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='200' height='200'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  background-size: 200px 200px;
}
html:not(.dark) .liquid-glass::before {
  opacity: 0.05;
  mix-blend-mode: multiply;
}

/* Cursor-tracking glow (::after) - appears on hover */
.liquid-glass::after {
  content: '';
  position: absolute;
  inset: 0;
  z-index: 4;
  pointer-events: none;
  border-radius: inherit;
  opacity: 0;
  transition: opacity 0.3s ease;
  background: radial-gradient(
    160px circle at var(--mx, 50%) var(--my, 50%),
    rgba(255, 255, 255, 0.04),
    rgba(255, 255, 255, 0.01) 40%,
    transparent 70%
  );
  mix-blend-mode: screen;
}
.liquid-glass:hover::after { opacity: 1; }
html:not(.dark) .liquid-glass::after {
  background: radial-gradient(
    160px circle at var(--mx, 50%) var(--my, 50%),
    rgba(255, 255, 255, 0.12),
    rgba(255, 255, 255, 0.04) 40%,
    transparent 70%
  );
  mix-blend-mode: soft-light;
}

/* .lg-mobile-flat - strips the wrapper on mobile (keeps nested cards) */
@media (max-width: 639px) {
  .liquid-glass.lg-mobile-flat {
    background: transparent !important;
    box-shadow: none !important;
    border-radius: 0 !important;
    overflow: visible !important;
    isolation: auto !important;
  }
  .lg-mobile-flat > .liquid-glass-effect,
  .lg-mobile-flat > .liquid-glass-tint,
  .lg-mobile-flat > .liquid-glass-shine {
    display: none !important;
  }
  .lg-mobile-flat::after,
  .lg-mobile-flat::before {
    display: none !important;
  }
  .lg-mobile-flat > .liquid-glass-content {
    padding: 0 !important;
  }
}

/* Touch-device gates - disable expensive effects */
@media (hover: none), (pointer: coarse) {
  .liquid-glass {
    content-visibility: visible;
    contain: none;
  }
  .liquid-glass::after,
  .liquid-glass:hover::after {
    display: none !important;
  }
  .liquid-glass-effect {
    backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
    -webkit-backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
  }
  .lg-macro > .liquid-glass-effect {
    backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
    -webkit-backdrop-filter: blur(2px) saturate(180%) brightness(1.06) contrast(1.04);
  }
}

/* Glass-off mode - strips every .liquid-glass container entirely */
html.glass-off .liquid-glass {
  background: transparent !important;
  box-shadow: none !important;
  border: none !important;
  overflow: visible !important;
  isolation: auto !important;
  contain: none !important;
  content-visibility: visible !important;
}
html.glass-off .liquid-glass-effect,
html.glass-off .liquid-glass-tint,
html.glass-off .liquid-glass-shine,
html.glass-off .liquid-glass::before,
html.glass-off .liquid-glass::after {
  display: none !important;
}

@media (prefers-reduced-motion: reduce) {
  .liquid-glass,
  a.liquid-glass:hover,
  .liquid-glass:hover {
    transition: none !important;
  }
}