/* ============================================================
   StudySnap — Design System  (v2: "Heritage" luxury theme)
   Forest green · warm cream · muted gold. Light, calm, premium.
   Performance-first: no blur, no continuous animation, soft shadows.
   ============================================================ */

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-behavior: smooth; }
body { min-height: 100%; line-height: 1.6; -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }
img, svg, picture { display: block; max-width: 100%; }
button, input, textarea, select { font: inherit; color: inherit; }
button { cursor: pointer; background: none; border: none; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
:focus-visible { outline: 2px solid var(--forest); outline-offset: 3px; border-radius: 4px; }
::selection { background: rgba(35, 79, 53, 0.16); }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}

/* ---------- Tokens ---------- */
:root {
  /* Color */
  --cream: #F8F5EE;
  --cream-2: #F2EEE3;
  --ivory: #FFFDF7;
  --forest: #234F35;
  --forest-700: #1B3E2A;
  --forest-600: #2C6043;
  --sage: #5E7763;
  --sage-soft: #8AA08C;
  --olive: #8A8C5A;
  --gold: #B08A4F;
  --gold-soft: #C7A877;
  --charcoal: #23231F;
  --charcoal-2: #45463F;
  --muted: #6C6D63;
  --line: rgba(35, 79, 53, 0.14);
  --line-soft: rgba(35, 79, 53, 0.08);

  /* Surfaces */
  --bg: var(--cream);
  --surface: var(--ivory);
  --surface-2: #FBF9F2;
  --on-forest: #F4F1E8;

  /* Type */
  --font-display: "Playfair Display", Georgia, "Times New Roman", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

  --fs-display: clamp(2.7rem, 6vw, 4.6rem);
  --fs-h1: clamp(2.1rem, 4.4vw, 3.3rem);
  --fs-h2: clamp(1.7rem, 3.2vw, 2.5rem);
  --fs-h3: 1.375rem;
  --fs-lead: clamp(1.05rem, 1.6vw, 1.25rem);
  --fs-body: 1rem;
  --fs-sm: 0.9375rem;
  --fs-xs: 0.8125rem;
  --fs-eyebrow: 0.78rem;

  /* Spacing (8pt) */
  --s-1: 0.25rem;  --s-2: 0.5rem;  --s-3: 0.75rem; --s-4: 1rem;
  --s-5: 1.5rem;   --s-6: 2rem;    --s-7: 3rem;    --s-8: 4rem;
  --s-9: 6rem;     --s-10: 8rem;

  /* Radius */
  --r-sm: 8px; --r: 14px; --r-lg: 22px; --r-xl: 30px; --r-pill: 999px;

  /* Soft, cheap shadows (small blur radii) */
  --shadow-sm: 0 1px 2px rgba(35, 79, 53, 0.05);
  --shadow: 0 2px 6px rgba(35, 79, 53, 0.06), 0 12px 28px rgba(35, 79, 53, 0.07);
  --shadow-lg: 0 4px 10px rgba(35, 79, 53, 0.07), 0 24px 48px rgba(35, 79, 53, 0.10);

  /* Motion */
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --t-fast: 140ms;
  --t: 240ms;

  /* Layout */
  --maxw: 1180px;
  --gutter: clamp(1.25rem, 5vw, 4rem);
  --nav-h: 72px;
}

/* ---------- Base ---------- */
body {
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  color: var(--charcoal);
  background: var(--bg);
  overflow-x: hidden;
}

h1, h2, h3, h4 { font-family: var(--font-display); font-weight: 600; line-height: 1.1; letter-spacing: -0.01em; color: var(--forest-700); }

p { color: var(--charcoal-2); }

/* ---------- Layout helpers ---------- */
.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--gutter); }
.section { padding-block: clamp(3.5rem, 9vw, 8rem); }
.stack > * + * { margin-top: var(--s-4); }
.center { text-align: center; }
.measure { max-width: 56ch; }
.measure-narrow { max-width: 44ch; }

/* ---------- Eyebrow / section head ---------- */
.eyebrow {
  display: inline-flex; align-items: center; gap: var(--s-2);
  font-family: var(--font-sans);
  font-size: var(--fs-eyebrow); font-weight: 600;
  letter-spacing: 0.16em; text-transform: uppercase;
  color: var(--gold);
}
.eyebrow::before { content: ""; width: 26px; height: 1px; background: var(--gold-soft); }
.center .eyebrow::before { display: none; }

.section-head { max-width: 60ch; margin-inline: auto; }
.section-head h2 { margin-top: var(--s-3); font-size: var(--fs-h2); }
.section-head p { margin-top: var(--s-4); font-size: var(--fs-lead); color: var(--muted); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--s-2);
  padding: 0.85rem 1.5rem; border-radius: var(--r-pill);
  font-size: var(--fs-sm); font-weight: 600; letter-spacing: 0.01em;
  white-space: nowrap;
  transition: transform var(--t-fast) var(--ease), background-color var(--t) var(--ease), color var(--t) var(--ease), border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
  will-change: transform;
}
.btn:active { transform: translateY(0) scale(0.985); }

.btn-primary { background: var(--forest); color: var(--on-forest); box-shadow: var(--shadow-sm); }
.btn-primary:hover { background: var(--forest-700); transform: translateY(-1px); box-shadow: var(--shadow); }

.btn-secondary { background: transparent; color: var(--forest); border: 1.5px solid var(--line); }
.btn-secondary:hover { border-color: var(--forest); transform: translateY(-1px); }

.btn-gold { background: var(--gold); color: #fff; }
.btn-gold:hover { background: #9d7a44; transform: translateY(-1px); }

.btn-ghost { color: var(--forest); padding-inline: var(--s-2); }
.btn-ghost:hover { color: var(--forest-700); }

.btn-lg { padding: 1rem 1.9rem; font-size: var(--fs-body); }
.btn-block { width: 100%; }
.btn[disabled] { opacity: 0.55; pointer-events: none; }

.btn-arrow svg { width: 18px; height: 18px; transition: transform var(--t) var(--ease); }
.btn-arrow:hover svg { transform: translateX(3px); }

/* ---------- Cards ---------- */
.card {
  background: var(--surface);
  border: 1px solid var(--line-soft);
  border-radius: var(--r-lg);
  padding: var(--s-6);
  box-shadow: var(--shadow-sm);
}
.card-hover { transition: transform var(--t) var(--ease), box-shadow var(--t) var(--ease), border-color var(--t) var(--ease); }
.card-hover:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--line); }

/* ---------- Chips / tags ---------- */
.chip {
  display: inline-flex; align-items: center; gap: var(--s-2);
  padding: 0.35rem 0.8rem; border-radius: var(--r-pill);
  font-size: var(--fs-xs); font-weight: 600;
  background: rgba(35, 79, 53, 0.06); color: var(--forest);
  border: 1px solid var(--line-soft);
}

/* ---------- Inputs ---------- */
.field { display: flex; flex-direction: column; gap: var(--s-2); text-align: left; }
.field label { font-size: var(--fs-xs); font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase; color: var(--muted); }
.input {
  width: 100%; padding: 0.85rem 1rem; border-radius: var(--r);
  background: var(--surface-2); border: 1.5px solid var(--line);
  color: var(--charcoal); font-size: var(--fs-sm);
  transition: border-color var(--t) var(--ease), background var(--t) var(--ease);
}
.input::placeholder { color: #9a9a8f; }
.input:focus { outline: none; border-color: var(--forest-600); background: #fff; }

/* ---------- Reveal-on-scroll (cheap: opacity + translateY, once) ----------
   Gated behind html.js so content is always visible if JS is off or fails. */
.js .reveal { opacity: 0; transform: translate3d(0, 18px, 0); transition: opacity .7s var(--ease), transform .7s var(--ease); will-change: opacity, transform; }
.js .reveal.is-in { opacity: 1; transform: translate3d(0, 0, 0); }
.js .reveal[data-delay="1"] { transition-delay: 80ms; }
.js .reveal[data-delay="2"] { transition-delay: 160ms; }
.js .reveal[data-delay="3"] { transition-delay: 240ms; }
@media (prefers-reduced-motion: reduce) { .js .reveal { opacity: 1; transform: none; transition: none; } }

/* ---------- Utilities ---------- */
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.text-gold { color: var(--gold); }
.text-forest { color: var(--forest); }
.divider { height: 1px; background: var(--line-soft); border: 0; }
.skip-link { position: absolute; left: -999px; top: 0; background: var(--forest); color: #fff; padding: var(--s-3) var(--s-4); border-radius: 0 0 var(--r) 0; z-index: 1000; }
.skip-link:focus { left: 0; }