/* ZStack Capital — shares the cutGPT ink / paper / coin system. */

:root {
  --ink: #070707;
  --ink-2: #111111;
  --paper: #f3eee4;
  --paper-2: #e8e1d4;
  --coin: #c8a96a;
  --graphite: rgba(243, 238, 228, 0.62);
  --rule: rgba(243, 238, 228, 0.1);
  --rule-strong: rgba(243, 238, 228, 0.18);
  --ease: cubic-bezier(0.23, 1, 0.32, 1);
  --measure: 72rem;
  --display: "Newsreader", "Times New Roman", serif;
  --sans: "IBM Plex Sans", "Helvetica Neue", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;

  --fg: var(--paper);
  --fg-muted: var(--graphite);
  --line: var(--rule);
  --btn-solid-bg: var(--paper);
  --btn-solid-fg: var(--ink);
  --btn-ghost-fg: var(--paper);
  --btn-ghost-line: var(--rule-strong);
}

.zs-surface-paper {
  --fg: var(--ink);
  --fg-muted: rgba(7, 7, 7, 0.68);
  --line: rgba(7, 7, 7, 0.14);
  --btn-solid-bg: var(--ink);
  --btn-solid-fg: var(--paper);
  --btn-ghost-fg: var(--ink);
  --btn-ghost-line: rgba(7, 7, 7, 0.22);
  background: var(--paper);
  color: var(--fg);
}

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

html { scroll-behavior: smooth; overflow-x: hidden; }

body.zs {
  margin: 0;
  min-height: 100vh;
  background: var(--ink);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

:focus-visible { outline: 2px solid var(--coin); outline-offset: 3px; }

a { color: inherit; text-underline-offset: 3px; text-decoration-color: var(--coin); }

h1, h2, h3 {
  font-family: var(--display);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.1;
  margin: 0 0 0.6em;
}

h1 { font-size: clamp(2.5rem, 5.5vw, 4.25rem); letter-spacing: -0.035em; }
h2 { font-size: clamp(1.8rem, 3.4vw, 2.6rem); }
h3 { font-size: 1.3rem; }

p { margin: 0 0 1em; }

.zs-wrap { width: min(100% - 2.5rem, var(--measure)); margin-inline: auto; }

.zs-skip {
  position: absolute; left: 1rem; top: -4rem; z-index: 100;
  background: var(--paper); color: var(--ink);
  padding: 0.65rem 1rem; font-weight: 600; text-decoration: none;
}
.zs-skip:focus { top: 1rem; }

.zs-kicker {
  font-family: var(--mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--coin);
  margin-bottom: 1rem;
}

.zs-lede { font-size: 1.15rem; color: var(--fg-muted); max-width: 40rem; }
.zs-sub { color: var(--fg-muted); max-width: 40rem; margin-bottom: 2.5rem; }
.zs-muted { color: var(--fg-muted); }

/* Buttons */
.zs-btn {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 44px; padding: 0.7rem 1.3rem;
  font-weight: 600; font-size: 0.95rem;
  text-decoration: none; border-radius: 999px;
  border: 1px solid transparent;
  transition: transform 160ms var(--ease), opacity 160ms var(--ease);
}
.zs-btn:active { transform: scale(0.97); }
.zs-btn-solid { background: var(--btn-solid-bg); color: var(--btn-solid-fg); }
.zs-btn-ghost { color: var(--btn-ghost-fg); border-color: var(--btn-ghost-line); }
@media (hover: hover) {
  .zs-btn:hover { opacity: 0.88; }
}
.zs-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: 2rem; }

/* Nav */
.zs-nav {
  position: sticky; top: 0; z-index: 30;
  background: rgba(7, 7, 7, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--rule);
}
.zs-nav-inner { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 1rem 0; }
.zs-brand {
  display: inline-flex; align-items: center; gap: 0.55rem;
  color: var(--paper); text-decoration: none;
  font-family: var(--display); font-weight: 600; font-size: 1.3rem; letter-spacing: -0.03em;
}
.zs-brand svg { color: var(--coin); }
.zs-nav-links { display: flex; align-items: center; gap: 1.5rem; }
.zs-nav-links a:not(.zs-btn) { color: var(--graphite); text-decoration: none; font-size: 0.95rem; }
@media (hover: hover) {
  .zs-nav-links a:not(.zs-btn):hover { color: var(--paper); }
}
.zs-nav-toggle {
  display: none; background: none; border: 1px solid var(--rule-strong);
  color: var(--paper); font-size: 1.1rem; width: 44px; height: 44px; border-radius: 10px;
}

@media (max-width: 720px) {
  .zs-nav-toggle { display: inline-flex; align-items: center; justify-content: center; }
  .zs-nav-links {
    display: none; position: absolute; left: 0; right: 0; top: 100%;
    flex-direction: column; align-items: stretch; gap: 0.25rem;
    padding: 1rem 1.25rem 1.25rem;
    background: var(--ink); border-bottom: 1px solid var(--rule);
  }
  .zs-nav-links.is-open { display: flex; }
  .zs-nav-links a:not(.zs-btn) { padding: 0.75rem 0; }
}

/* Hero */
.zs-hero { padding: clamp(4rem, 10vw, 7.5rem) 0 clamp(3.5rem, 8vw, 6rem); border-bottom: 1px solid var(--rule); }
.zs-hero-grid { display: grid; grid-template-columns: 1.5fr 1fr; gap: clamp(2rem, 5vw, 4.5rem); align-items: end; }
.zs-ledger-card {
  border: 1px solid var(--rule-strong);
  border-radius: 18px;
  padding: 1.5rem;
  background: linear-gradient(180deg, rgba(200, 169, 106, 0.08), transparent 60%);
}
.zs-ledger-label {
  font-family: var(--mono); font-size: 0.68rem; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--coin); margin-bottom: 0.75rem;
}
.zs-ledger-card dl { margin: 0; }
.zs-ledger-card dl > div {
  display: flex; justify-content: space-between; gap: 1rem;
  padding: 0.85rem 0; border-top: 1px dashed var(--rule-strong);
}
.zs-ledger-card dt { color: var(--graphite); }
.zs-ledger-card dd { margin: 0; font-family: var(--mono); font-variant-numeric: tabular-nums; }

/* Sections */
.zs-section { padding: clamp(4rem, 8vw, 6.5rem) 0; }
.zs-section-follow { border-top: 1px solid var(--rule); }

.zs-apps {
  list-style: none; margin: 0; padding: 0;
  display: grid; grid-template-columns: repeat(auto-fill, minmax(18rem, 1fr)); gap: 1rem;
}
.zs-app {
  display: flex; gap: 1rem; align-items: flex-start;
  padding: 1.35rem; border: 1px solid var(--rule); border-radius: 18px;
  background: var(--ink-2);
  transition: border-color 200ms var(--ease);
}
@media (hover: hover) {
  .zs-app:hover { border-color: var(--rule-strong); }
}
.zs-app img { flex: none; border-radius: 14px; box-shadow: 0 0 0 1px var(--rule); }
.zs-app h3 { margin-bottom: 0.35rem; }
.zs-app p { color: var(--graphite); font-size: 0.95rem; margin-bottom: 0.6rem; }
.zs-app-cat {
  font-family: var(--mono); font-size: 0.66rem !important; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--coin) !important; margin-bottom: 0.35rem !important;
}
.zs-app-links { display: flex; gap: 1rem; margin: 0 !important; }
.zs-app-links a { color: var(--paper); font-weight: 500; font-size: 0.9rem; }

.zs-how { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--rule); border: 1px solid var(--rule); border-radius: 18px; overflow: hidden; margin-top: 2rem; }
.zs-how article { background: var(--ink); padding: 1.75rem; }
.zs-how p { color: var(--graphite); margin: 0; }
.zs-n { display: block; font-family: var(--mono); color: var(--coin); font-size: 0.8rem; margin-bottom: 1.25rem; }

.zs-cta { padding: clamp(4rem, 8vw, 6rem) 0; }
.zs-cta-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 3rem; align-items: center; }
.zs-cta p { color: var(--fg-muted); }

/* Address */
.zs-address { font-style: normal; line-height: 1.75; color: var(--fg-muted); }
.zs-address strong { color: var(--fg); font-weight: 600; }
.zs-address a { color: var(--fg); }
.zs-cta .zs-address {
  border: 1px solid var(--line); border-radius: 18px; padding: 1.5rem; background: var(--paper-2);
}

/* Inner pages */
.zs-page { padding: clamp(3.5rem, 8vw, 6rem) 0 clamp(4rem, 8vw, 6.5rem); }
.zs-prose { max-width: 46rem; }
.zs-prose h2 { font-size: 1.6rem; margin-top: 2.5rem; }
.zs-prose p, .zs-prose li { color: var(--graphite); }
.zs-prose li { margin-bottom: 0.6rem; }
.zs-prose strong { color: var(--paper); }
.zs-prose a { color: var(--paper); }
.zs-prose .zs-address { margin-bottom: 1rem; }

.zs-contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; margin: 2.5rem 0 1rem; }
.zs-contact-card { border: 1px solid var(--rule-strong); border-radius: 18px; padding: 1.5rem; background: var(--ink-2); }
.zs-contact-card h2 {
  font-family: var(--mono); font-size: 0.72rem; font-weight: 500;
  letter-spacing: 0.14em; text-transform: uppercase; color: var(--coin);
}
.zs-contact-card p { font-size: 1.1rem; }
.zs-contact-card p.zs-muted { font-size: 0.92rem; }
.zs-contact-card a { color: var(--paper); }
.zs-contact-notes { margin-top: 1rem; }

/* Footer */
.zs-foot { border-top: 1px solid var(--rule); padding: 3.5rem 0 2rem; }
.zs-foot-grid { display: grid; grid-template-columns: 1.3fr 0.8fr 0.8fr 1.4fr; gap: 2rem; }
.zs-foot h3 {
  font-family: var(--mono); font-size: 0.7rem; font-weight: 500;
  letter-spacing: 0.14em; text-transform: uppercase; color: var(--coin);
}
.zs-foot ul { list-style: none; margin: 0; padding: 0; }
.zs-foot li { margin-bottom: 0.5rem; }
.zs-foot li a { color: var(--graphite); text-decoration: none; }
@media (hover: hover) {
  .zs-foot li a:hover { color: var(--paper); }
}
.zs-foot .zs-brand { margin-bottom: 0.75rem; }
.zs-foot .zs-address { font-size: 0.92rem; }
.zs-copy { margin-top: 2.5rem; padding-top: 1.5rem; border-top: 1px solid var(--rule); color: var(--graphite); font-size: 0.85rem; }

@media (max-width: 900px) {
  .zs-hero-grid, .zs-cta-grid { grid-template-columns: 1fr; }
  .zs-how, .zs-contact-grid { grid-template-columns: 1fr; }
  .zs-foot-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 520px) {
  .zs-foot-grid { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .zs-btn, .zs-app { transition: none; }
}