/* ============================================================
   CryptoStack Donations — landing styles
   Aesthetic: warm-obsidian "on-chain" precision, tri-chain accents,
   serif display (Fraunces) + grotesque body (Hanken) + mono data.
   ============================================================ */

:root {
  --bg:        #0e0d12;
  --bg-2:      #14121b;
  --surface:   rgba(255,255,255,0.028);
  --surface-2: #1a1822;
  --line:      rgba(255,255,255,0.10);
  --line-2:    rgba(255,255,255,0.06);

  --ink:       #edeaf2;
  --ink-soft:  #c8c4d4;
  --muted:     #948fa3;

  --btc:  #f7931a;   /* Bitcoin amber — primary accent */
  --mint: #3fd7a0;   /* Solana green, tempered */
  --iris: #8e8bf5;   /* Ethereum periwinkle */

  --primary:    var(--btc);
  --primary-ink:#1a1206;

  --font-display: 'Fraunces', Georgia, 'Times New Roman', serif;
  --font-body:    'Hanken Grotesk', system-ui, -apple-system, sans-serif;
  --font-mono:    'JetBrains Mono', ui-monospace, 'SFMono-Regular', monospace;

  --maxw: 1140px;
  --radius: 16px;
  --radius-sm: 10px;
  --ease: cubic-bezier(.22,.61,.36,1);
}

/* ---------- reset / base ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
  font-size: 1.0625rem;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
  position: relative;
}

/* atmosphere: radial glows + engineered grid + grain */
body::before {
  content: "";
  position: fixed; inset: 0;
  background:
    radial-gradient(60% 50% at 78% -8%, rgba(247,147,26,0.14), transparent 60%),
    radial-gradient(45% 45% at 8% 12%, rgba(142,139,245,0.12), transparent 60%),
    radial-gradient(55% 60% at 50% 108%, rgba(63,215,160,0.07), transparent 60%);
  z-index: -3; pointer-events: none;
}
body::after {
  content: "";
  position: fixed; inset: 0;
  background-image:
    linear-gradient(var(--line-2) 1px, transparent 1px),
    linear-gradient(90deg, var(--line-2) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(120% 80% at 50% 0%, #000 35%, transparent 78%);
  z-index: -2; pointer-events: none; opacity: .5;
}

img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
code { font-family: var(--font-mono); font-size: .9em; }

/* ---------- layout ---------- */
.wrap { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: 24px; }
.wrap-narrow { max-width: 800px; }

.section { padding-block: clamp(64px, 9vw, 116px); position: relative; }
.section-alt { background:
    linear-gradient(180deg, transparent, rgba(255,255,255,0.015) 14%, rgba(255,255,255,0.015) 86%, transparent);
  border-block: 1px solid var(--line-2); }

.section-head { max-width: 720px; margin-bottom: clamp(36px, 5vw, 60px); }
.section-head h2 {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(1.9rem, 4vw, 2.95rem);
  line-height: 1.08;
  letter-spacing: -0.015em;
}
.section-sub { color: var(--ink-soft); margin-top: 16px; font-size: 1.1rem; max-width: 60ch; }

/* ---------- eyebrow ---------- */
.eyebrow {
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 18px;
  display: inline-flex; align-items: center; gap: 10px;
}
.eyebrow::before {
  content: ""; width: 26px; height: 1px; background: var(--btc); opacity: .8;
}

/* ---------- header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: blur(12px);
  background: color-mix(in srgb, var(--bg) 72%, transparent);
  border-bottom: 1px solid var(--line-2);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--ink); }
.brand-mark { color: var(--ink); display: grid; place-items: center; }
.brand-name { font-family: var(--font-display); font-weight: 600; font-size: 1.12rem; letter-spacing: -0.01em; }
.brand-dim { color: var(--muted); font-weight: 500; }

.nav { display: flex; align-items: center; }
.nav-menu { list-style: none; display: flex; align-items: center; gap: 30px; padding: 0; }
.nav-menu a { color: var(--ink-soft); font-size: .95rem; font-weight: 500; transition: color .2s; }
.nav-menu a:hover { color: var(--ink); }
.nav-cta {
  color: var(--primary-ink) !important;
  background: var(--primary);
  padding: 9px 16px; border-radius: 999px; font-weight: 600 !important;
  transition: transform .2s var(--ease), box-shadow .2s;
}
.nav-cta:hover { transform: translateY(-1px); box-shadow: 0 8px 24px rgba(247,147,26,.28); }

.nav-toggle { display: none; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--ink); border-radius: 2px; transition: .25s var(--ease); }
.nav-toggle span + span { margin-top: 5px; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 9px;
  font-weight: 600; font-size: .98rem;
  padding: 13px 22px; border-radius: 999px;
  border: 1px solid transparent; cursor: pointer;
  transition: transform .2s var(--ease), box-shadow .25s, background .2s, border-color .2s;
}
.btn-primary { background: var(--primary); color: var(--primary-ink); box-shadow: 0 10px 30px rgba(247,147,26,.22); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 40px rgba(247,147,26,.34); }
.btn-ghost { background: var(--surface); color: var(--ink); border-color: var(--line); }
.btn-ghost:hover { transform: translateY(-2px); border-color: rgba(255,255,255,.28); background: rgba(255,255,255,.06); }

/* ---------- hero ---------- */
.hero { padding-top: clamp(48px, 7vw, 88px); padding-bottom: clamp(40px, 6vw, 64px); }
.hero-grid {
  display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(32px, 5vw, 64px); align-items: center;
}
.hero-copy h1 {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(2.5rem, 6.2vw, 4.4rem);
  line-height: 1.02;
  letter-spacing: -0.025em;
  margin-top: 6px;
}
.hero-copy h1 .accent {
  color: var(--btc);
  font-style: italic;
  font-variation-settings: "SOFT" 0;
}
.lede { color: var(--ink-soft); font-size: clamp(1.08rem, 2vw, 1.28rem); margin-top: 22px; max-width: 32ch; }
.lede strong { color: var(--ink); font-weight: 600; }
.cta-row { display: flex; gap: 14px; margin-top: 32px; flex-wrap: wrap; }
.cta-center { justify-content: center; }
.cta-note { margin-top: 16px; font-size: .85rem; color: var(--muted); font-family: var(--font-mono); }
.cta-note .soon { color: var(--mint); }

/* hero signature: donation flow card */
.hero-demo { position: relative; }
.demo-card {
  position: relative; z-index: 2;
  background: linear-gradient(165deg, var(--surface-2), #131119);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: 0 30px 80px -30px rgba(0,0,0,.8), inset 0 1px 0 rgba(255,255,255,.04);
}
.demo-head {
  display: flex; align-items: center; gap: 9px;
  font-weight: 600; font-size: .98rem; color: var(--ink);
}
.demo-dot { width: 9px; height: 9px; border-radius: 50%; background: var(--mint); box-shadow: 0 0 0 4px rgba(63,215,160,.16); }
.demo-secure {
  margin-left: auto; font-family: var(--font-mono); font-size: .66rem; letter-spacing: .08em;
  text-transform: uppercase; color: var(--mint);
  border: 1px solid rgba(63,215,160,.35); padding: 3px 8px; border-radius: 999px;
}
.demo-amount { display: flex; align-items: baseline; gap: 12px; margin: 20px 0 6px; }
.demo-cur { font-family: var(--font-display); font-weight: 600; font-size: 2.6rem; letter-spacing: -0.02em; }
.demo-eq { font-family: var(--font-mono); color: var(--muted); font-size: .85rem; }

.chain-pills { display: flex; gap: 8px; margin: 16px 0 18px; flex-wrap: wrap; }
.pill {
  font-family: var(--font-mono); font-size: .78rem; font-weight: 500;
  padding: 7px 13px; border-radius: 999px; cursor: pointer;
  background: rgba(255,255,255,.04); border: 1px solid var(--line); color: var(--ink-soft);
  transition: .2s var(--ease);
}
.pill-btc.is-active { background: rgba(247,147,26,.14); border-color: rgba(247,147,26,.5); color: var(--btc); }
.pill:hover { border-color: rgba(255,255,255,.3); color: var(--ink); }

.demo-flow {
  background: rgba(0,0,0,.25); border: 1px solid var(--line-2);
  border-radius: var(--radius-sm); padding: 14px 16px;
}
.flow-row { display: flex; align-items: center; gap: 12px; }
.flow-label {
  font-family: var(--font-mono); font-size: .68rem; text-transform: uppercase;
  letter-spacing: .1em; color: var(--muted); width: 38px; flex-shrink: 0;
}
.flow-addr { font-family: var(--font-mono); font-size: .82rem; color: var(--ink-soft); }
.flow-addr em { color: var(--muted); font-style: normal; }
.flow-yours { color: var(--btc); }
.flow-line { height: 22px; margin-left: 12px; border-left: 1px dashed rgba(255,255,255,.2); position: relative; }
.flow-spark {
  position: absolute; left: -4px; top: 0; width: 7px; height: 7px; border-radius: 50%;
  background: var(--btc); box-shadow: 0 0 10px var(--btc);
  animation: drip 2.6s var(--ease) infinite;
}
@keyframes drip { 0% { top: -2px; opacity: 0; } 18% { opacity: 1; } 82% { opacity: 1; } 100% { top: 20px; opacity: 0; } }

.demo-btn {
  margin-top: 16px; text-align: center; font-weight: 600; font-size: .95rem;
  background: var(--primary); color: var(--primary-ink);
  padding: 13px; border-radius: 999px;
}
.demo-glow {
  position: absolute; inset: 8% -6% -14% 8%; z-index: 1;
  background: radial-gradient(closest-side, rgba(247,147,26,.20), transparent 72%);
  filter: blur(10px);
}

/* trust strip */
.trust-strip {
  display: flex; flex-wrap: wrap; align-items: center; gap: 18px;
  margin-top: clamp(40px, 6vw, 72px);
  padding-top: 24px; border-top: 1px solid var(--line-2);
  font-family: var(--font-mono); font-size: .8rem; letter-spacing: .04em; color: var(--muted);
}
.trust-strip i { width: 4px; height: 4px; border-radius: 50%; background: var(--line); }

/* ---------- features ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.card {
  background: var(--surface); border: 1px solid var(--line-2);
  border-radius: var(--radius); padding: 26px 24px;
  transition: transform .25s var(--ease), border-color .25s, background .25s;
}
.card:hover { transform: translateY(-4px); border-color: var(--line); background: rgba(255,255,255,.04); }
.card-ic {
  width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center;
  font-size: 1.3rem; margin-bottom: 18px; border: 1px solid var(--line);
}
.ic-amber { color: var(--btc); background: rgba(247,147,26,.10); border-color: rgba(247,147,26,.3); }
.ic-mint  { color: var(--mint); background: rgba(63,215,160,.10); border-color: rgba(63,215,160,.3); }
.ic-iris  { color: var(--iris); background: rgba(142,139,245,.10); border-color: rgba(142,139,245,.3); }
.card h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.22rem; margin-bottom: 8px; letter-spacing: -0.01em; }
.card p { color: var(--muted); font-size: .98rem; }
.card code { color: var(--ink-soft); background: rgba(255,255,255,.06); padding: 1px 5px; border-radius: 5px; }

/* ---------- chains ---------- */
.chain-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.chain-card {
  border-radius: var(--radius); padding: 28px 26px;
  border: 1px solid var(--line); position: relative; overflow: hidden;
  background: var(--surface-2);
}
.chain-card::before {
  content: ""; position: absolute; inset: 0 0 auto 0; height: 3px;
}
.chain-btc::before { background: var(--btc); }
.chain-eth::before { background: var(--iris); }
.chain-sol::before { background: var(--mint); }
.chain-top { display: flex; align-items: center; gap: 14px; margin-bottom: 14px; }
.chain-glyph {
  width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center;
  font-size: 1.5rem; font-weight: 700; border: 1px solid var(--line);
}
.chain-btc .chain-glyph { color: var(--btc); background: rgba(247,147,26,.10); }
.chain-eth .chain-glyph { color: var(--iris); background: rgba(142,139,245,.10); }
.chain-sol .chain-glyph { color: var(--mint); background: rgba(63,215,160,.10); }
.chain-card h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.3rem; letter-spacing: -0.01em; }
.chain-card p { color: var(--muted); font-size: .97rem; margin-bottom: 16px; }
.chain-card code { color: var(--ink-soft); }
.chain-tags { list-style: none; display: flex; flex-wrap: wrap; gap: 7px; padding: 0; }
.chain-tags li {
  font-family: var(--font-mono); font-size: .72rem; letter-spacing: .03em;
  padding: 4px 9px; border-radius: 6px; background: rgba(255,255,255,.05);
  border: 1px solid var(--line-2); color: var(--ink-soft);
}

/* ---------- steps ---------- */
.steps { list-style: none; counter-reset: none; padding: 0; display: grid; gap: 4px; max-width: 860px; }
.step { display: grid; grid-template-columns: 84px 1fr; gap: 8px; padding: 26px 0; border-top: 1px solid var(--line-2); }
.step:first-child { border-top: 0; }
.step-no { font-family: var(--font-mono); font-size: 1.05rem; color: var(--btc); padding-top: 4px; }
.step h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.32rem; margin-bottom: 6px; letter-spacing: -0.01em; }
.step p { color: var(--muted); max-width: 56ch; }
.step code { color: var(--ink-soft); background: rgba(255,255,255,.06); padding: 1px 5px; border-radius: 5px; }

/* ---------- faq ---------- */
.faq { display: grid; gap: 0; }
.faq details {
  border-bottom: 1px solid var(--line-2);
}
.faq summary {
  list-style: none; cursor: pointer; padding: 22px 44px 22px 0; position: relative;
  font-family: var(--font-display); font-weight: 600; font-size: 1.16rem; letter-spacing: -0.01em;
  transition: color .2s;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; position: absolute; right: 6px; top: 50%; transform: translateY(-50%);
  font-family: var(--font-body); font-weight: 400; font-size: 1.6rem; color: var(--btc); transition: transform .25s var(--ease);
}
.faq details[open] summary::after { transform: translateY(-50%) rotate(45deg); }
.faq summary:hover { color: var(--btc); }
.faq-body { padding: 0 44px 24px 0; }
.faq-body p { color: var(--ink-soft); }
.faq-body code { color: var(--btc); background: rgba(247,147,26,.10); padding: 1px 5px; border-radius: 5px; }
.faq details[open] .faq-body { animation: fadein .35s var(--ease); }
@keyframes fadein { from { opacity: 0; transform: translateY(-4px); } to { opacity: 1; transform: none; } }

/* ---------- final cta ---------- */
.cta-final { padding-block: clamp(72px, 10vw, 130px); position: relative; }
.cta-final::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(60% 80% at 50% 120%, rgba(247,147,26,.16), transparent 70%);
  z-index: -1;
}
.cta-final-inner { text-align: center; max-width: 720px; }
.cta-final h2 {
  font-family: var(--font-display); font-weight: 500;
  font-size: clamp(2.1rem, 5vw, 3.4rem); line-height: 1.05; letter-spacing: -0.02em;
}
.cta-final p { color: var(--ink-soft); margin-top: 16px; font-size: 1.15rem; }
.cta-final .cta-row { margin-top: 32px; }

/* ---------- footer ---------- */
.site-footer { border-top: 1px solid var(--line-2); padding-top: 64px; background: rgba(0,0,0,.2); }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; padding-bottom: 48px; }
.footer-brand .brand-name { font-size: 1.2rem; }
.footer-brand p { color: var(--muted); margin-top: 14px; max-width: 42ch; font-size: .95rem; }
.footer-col h4 {
  font-family: var(--font-mono); font-size: .74rem; text-transform: uppercase; letter-spacing: .12em;
  color: var(--muted); margin-bottom: 16px; font-weight: 500;
}
.footer-col ul { list-style: none; padding: 0; display: grid; gap: 11px; }
.footer-col a { color: var(--ink-soft); font-size: .95rem; transition: color .2s; }
.footer-col a:hover { color: var(--btc); }
.footer-bottom { border-top: 1px solid var(--line-2); padding-block: 26px; display: grid; gap: 10px; }
.footer-bottom p { color: var(--muted); font-size: .85rem; }
.footer-fine { color: #6e6a7a !important; font-size: .8rem !important; max-width: 80ch; }

/* ---------- prose (why) ---------- */
.prose-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 38px; }
.prose-col p { color: var(--ink-soft); margin-bottom: 16px; }
.prose-col p:last-child { margin-bottom: 0; }

/* ---------- use cases ---------- */
.use-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.use {
  border: 1px solid var(--line-2); border-radius: var(--radius); padding: 24px 22px;
  background: var(--surface); transition: border-color .25s, transform .25s var(--ease);
}
.use:hover { border-color: var(--line); transform: translateY(-3px); }
.use h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.12rem; margin-bottom: 8px; letter-spacing: -0.01em; }
.use p { color: var(--muted); font-size: .94rem; }

/* ---------- difference ---------- */
.diff-list { display: grid; gap: 0; }
.diff { padding: 26px 0; border-top: 1px solid var(--line-2); }
.diff:first-child { border-top: 0; padding-top: 0; }
.diff h3 {
  font-family: var(--font-mono); font-weight: 500; font-size: .82rem; letter-spacing: .04em;
  text-transform: uppercase; color: var(--btc); margin-bottom: 10px;
}
.diff p { color: var(--ink-soft); }

/* ---------- skip link ---------- */
.skip-link {
  position: absolute; left: -9999px; top: 8px; z-index: 100;
  background: var(--primary); color: var(--primary-ink); padding: 10px 16px; border-radius: 8px; font-weight: 600;
}
.skip-link:focus { left: 16px; }

/* ---------- focus ---------- */
:focus-visible { outline: 2px solid var(--btc); outline-offset: 3px; border-radius: 4px; }

/* ---------- reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(16px); animation: rise .7s var(--ease) forwards; }
.d1 { animation-delay: .08s; } .d2 { animation-delay: .16s; }
.d3 { animation-delay: .24s; } .d4 { animation-delay: .34s; }
@keyframes rise { to { opacity: 1; transform: none; } }

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; animation: none; }
  .flow-spark, .faq details[open] .faq-body { animation: none; }
  .btn, .card, .nav-cta { transition: none; }
}

/* ---------- responsive ---------- */
@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-demo { max-width: 440px; }
  .feature-grid, .chain-grid { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
  .prose-grid { grid-template-columns: 1fr; gap: 8px; }
  .use-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 680px) {
  .nav-toggle { display: block; }
  .nav-menu {
    position: absolute; top: 68px; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--bg-2); border-bottom: 1px solid var(--line);
    padding: 10px 24px 22px; gap: 4px;
    clip-path: inset(0 0 100% 0); opacity: 0; pointer-events: none;
    transition: clip-path .3s var(--ease), opacity .3s;
  }
  .nav-menu.open { clip-path: inset(0 0 0 0); opacity: 1; pointer-events: auto; }
  .nav-menu li { padding: 6px 0; }
  .nav-menu a { display: block; padding: 8px 0; font-size: 1rem; }
  .nav-cta { text-align: center; }
  .nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
  .nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

  .feature-grid, .chain-grid { grid-template-columns: 1fr; }
  .use-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .step { grid-template-columns: 56px 1fr; }
  .demo-cur { font-size: 2.1rem; }
}