/* ============================================================
   SILICAIRN — Design System (redesign)
   "Glassy panels over rolling green hills."
   Warm paper · meadow green · ink · real glass · squircles.
   Stand-in fonts: Shrikhand → Cooper BT · Jost → Avant Garde
   Gothic · Hanken Grotesk → final body face (TBD).
   ============================================================ */

:root {
  /* --- Palette --- */
  --paper:      #F6F2E9;   /* warm off-white page */
  --paper-2:    #EFE9DB;   /* raised cream */
  --paper-3:    #E7DFCD;   /* sunk cream / hairline fill */
  --ink:        #14110E;   /* warm near-black */
  --ink-2:      #2A2620;

  --green-900:  #123A26;
  --green-700:  #1F5C3C;   /* brand anchor */
  --green-500:  #2F8B57;   /* primary */
  --green-300:  #84C79E;   /* light accent / glow */
  --amber:      #E0913E;   /* sole warm accent (old red retired) */

  --hairline:   rgba(20, 17, 14, 0.12);
  --hairline-2: rgba(20, 17, 14, 0.07);

  /* On dark/ink + on-photo surfaces */
  --on-ink:        #F6F2E9;
  --on-ink-soft:   rgba(246, 242, 233, 0.74);
  --on-ink-muted:  rgba(246, 242, 233, 0.55);

  --text:        var(--ink);
  --text-soft:   rgba(20, 17, 14, 0.66);
  --text-muted:  rgba(20, 17, 14, 0.50);

  /* --- Glass --- */
  --glass-bg:      rgba(255, 255, 255, 0.16);
  --glass-bg-ink:  rgba(20, 30, 22, 0.28);
  --glass-border:  rgba(255, 255, 255, 0.55);
  --glass-blur:    16px;
  --glass-sat:     135%;
  --glass-shadow:  0 24px 60px -22px rgba(18, 40, 25, 0.40);
  --glass-shadow-sm: 0 12px 32px -16px rgba(18, 40, 25, 0.34);
  --sheen: linear-gradient(180deg, rgba(255,255,255,0.55) 0%, rgba(255,255,255,0.08) 38%, rgba(255,255,255,0) 70%);

  /* --- Type — Apple/techy: Geist (≈SF Pro) for display+body, Geist Mono (≈SF Mono) for labels --- */
  --font-display: 'Geist', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-label:   'Geist Mono', ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
  --font-body:    'Geist', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* --- Radius (squircle-ish) --- */
  --r-panel: 24px;
  --r-tile:  20px;
  --r-soft:  12px;
  --r-pill:  999px;

  /* --- Spacing (8pt) --- */
  --s-1:.25rem; --s-2:.5rem; --s-3:.75rem; --s-4:1rem;
  --s-6:1.5rem; --s-8:2rem; --s-12:3rem; --s-16:4rem;
  --s-20:5rem; --s-24:6rem; --s-32:8rem;

  /* --- Layout --- */
  --maxw: 1240px;
  --margin: 48px;
  --nav-h: 68px;

  /* --- Motion --- */
  --ease: cubic-bezier(.4, 0, .2, 1);
  --ease-out: cubic-bezier(.16, 1, .3, 1);
  --dur: .5s;
}

/* ============================================================
   Reset & base
   ============================================================ */

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-padding-top: var(--nav-h);
  text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-weight: 400;
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--text);
  background: var(--paper);
  overflow-x: hidden;
}

img, svg, canvas { display: block; max-width: 100%; }
img { height: auto; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
ul { list-style: none; }

::selection { background: var(--green-300); color: var(--ink); }

:focus-visible {
  outline: 2px solid var(--green-700);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ============================================================
   Layout primitives
   ============================================================ */

.container {
  width: 100%;
  max-width: calc(var(--maxw) + var(--margin) * 2);
  margin: 0 auto;
  padding: 0 var(--margin);
}

.section { padding: var(--s-24) 0; position: relative; }
.section--tight { padding: var(--s-16) 0; }

.measure { max-width: 62ch; }
.measure-wide { max-width: 780px; }

/* ============================================================
   Type utilities
   ============================================================ */

.display {
  font-family: var(--font-display);
  font-weight: 600;                 /* Geist SemiBold — SF Pro Display feel */
  font-size: clamp(2.75rem, 7vw, 5rem);
  line-height: 1.02;
  letter-spacing: -0.028em;         /* tight negative tracking — Apple large-title look */
  color: var(--ink);
}

.h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.9rem, 4.2vw, 3rem);
  line-height: 1.06;
  letter-spacing: -0.02em;
}

.h3 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.35rem, 2.4vw, 1.85rem);
  line-height: 1.1;
}

.eyebrow, .label {
  font-family: var(--font-label);
  font-size: 0.72rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;            /* mono runs wide — tighter tracking reads as a clean techy label */
  color: var(--green-700);
}
.eyebrow--ink, .label--ink { color: var(--on-ink-soft); }
.eyebrow--amber { color: var(--amber); }

.lead {
  font-size: clamp(1.0625rem, 1.5vw, 1.3rem);
  line-height: 1.6;
  color: var(--text-soft);
}

.body { font-size: 1.0625rem; line-height: 1.7; color: var(--text-soft); }
.body + .body { margin-top: var(--s-4); }

.on-ink { color: var(--on-ink); }
.on-ink-soft { color: var(--on-ink-soft); }

.accent { color: var(--amber); }
.tok { font-family: var(--font-label); font-weight: 600; letter-spacing: 0.01em; }

/* ============================================================
   Cairn signature: stacked-hairline divider
   ============================================================ */

.cairn-divider {
  display: flex; flex-direction: column; align-items: flex-start;
  gap: 4px; margin-bottom: var(--s-8); width: 56px;
}
.cairn-divider span { display: block; height: 2px; border-radius: 2px; background: var(--green-500); opacity: .85; }
.cairn-divider span:nth-child(1) { width: 56px; }
.cairn-divider span:nth-child(2) { width: 40px; }
.cairn-divider span:nth-child(3) { width: 28px; }
.cairn-divider span:nth-child(4) { width: 16px; }
.cairn-divider--ink span { background: var(--green-300); }

/* ============================================================
   Glass — the primary material
   ============================================================ */

.glass {
  position: relative;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: var(--r-panel);
  box-shadow: var(--glass-shadow);
  contain: paint;
  isolation: isolate;
}
/* specular top-sheen */
.glass::before {
  content: '';
  position: absolute; inset: 0;
  border-radius: inherit;
  background: var(--sheen);
  opacity: .9;
  pointer-events: none;
  mix-blend-mode: screen;
  z-index: -1;
}
@supports ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .glass {
    -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-sat));
    backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-sat));
  }
}
@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .glass { background: rgba(246, 242, 233, 0.92); border-color: var(--hairline); }
}
.glass--ink { background: var(--glass-bg-ink); border-color: rgba(255,255,255,0.18); color: var(--on-ink); }
.glass--ink::before { opacity: .35; }

/* ============================================================
   Buttons
   ============================================================ */

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  min-height: 46px; padding: 0 1.6rem;
  font-family: var(--font-label); font-size: .9rem; font-weight: 600; letter-spacing: .02em;
  border-radius: var(--r-soft);
  border: 1px solid transparent;
  transition: transform .2s var(--ease), background-color .2s var(--ease), border-color .2s var(--ease), color .2s var(--ease);
}
.btn:active { transform: translateY(1px); }

.btn-primary { background: var(--green-700); color: var(--paper); border-color: var(--green-700); }
.btn-primary:hover { background: var(--green-900); border-color: var(--green-900); }

.btn-ghost { background: transparent; color: var(--ink); border-color: var(--hairline); }
.btn-ghost:hover { border-color: var(--green-700); color: var(--green-700); }
.btn-ghost--ink { color: var(--on-ink); border-color: rgba(255,255,255,0.4); }
.btn-ghost--ink:hover { background: rgba(255,255,255,0.1); border-color: var(--on-ink); color: var(--on-ink); }

.btn-full { width: 100%; }

.arrow-link {
  display: inline-flex; align-items: center; gap: .45rem;
  font-family: var(--font-label); font-weight: 600; font-size: .9rem; letter-spacing: .02em;
  color: var(--green-700); transition: gap .2s var(--ease), color .2s var(--ease);
}
.arrow-link svg { width: 15px; height: 15px; transition: transform .2s var(--ease); }
.arrow-link:hover { color: var(--green-900); }
.arrow-link:hover svg { transform: translateX(3px); }

/* waypoint chip */
.waypoint {
  display: inline-flex; align-items: center; gap: .55rem; margin-top: var(--s-6);
  font-family: var(--font-label); font-size: .78rem; letter-spacing: .04em; color: var(--text-soft);
}
.waypoint::before { content: ''; width: 9px; height: 9px; background: var(--amber); border-radius: 2px; flex: none; }
.waypoint--ink { color: var(--on-ink-soft); }

/* ============================================================
   Scroll reveal
   ============================================================ */

.reveal { opacity: 0; transform: translateY(20px); transition: opacity .7s var(--ease-out), transform .7s var(--ease-out); }
.reveal.visible { opacity: 1; transform: none; }

/* ============================================================
   Reduced motion
   ============================================================ */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  *, *::before, *::after { animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; }
}

/* ============================================================
   Responsive tokens
   ============================================================ */

@media (max-width: 1024px) { :root { --margin: 32px; } }
@media (max-width: 768px)  { :root { --margin: 20px; --s-24: 4.5rem; --s-20: 3.5rem; } .section { padding: var(--s-20) 0; } }
@media (max-width: 480px)  { :root { --margin: 16px; --r-panel: 20px; } }