/* Billverso landing. Static, no JavaScript, no external requests. */

:root {
  color-scheme: dark;
  --bg: #000;
  --s1: rgba(255, 255, 255, .03);
  --s2: rgba(255, 255, 255, .05);
  --s3: rgba(255, 255, 255, .09);
  --line: rgba(255, 255, 255, .1);
  --text: #f2f2f3;
  --text-2: rgba(255, 255, 255, .74);
  --muted: rgba(255, 255, 255, .58);
  --dim: rgba(255, 255, 255, .5);
  --accent: #b9a6ff;
  --accent-soft: rgba(185, 166, 255, .14);
  --s1-solid: #080808;
  --sans: Inter, "Inter Variable", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  --gutter: clamp(20px, 4vw, 40px);
  --max: 1240px;
}

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

html {
  background: var(--bg);
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100svh;
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.55;
  font-feature-settings: "cv11", "ss01";
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

h1, h2, p, ul, ol, dl, dd, figure { margin: 0; }
main { flex: 1 0 auto; }
ul, ol { padding: 0; list-style: none; }
q { quotes: "\201C" "\201D"; }
p, dd { text-wrap: pretty; }

a { color: inherit; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 6px;
}

.sr {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

.skip {
  position: absolute;
  left: 12px;
  top: -60px;
  z-index: 20;
  padding: 10px 14px;
  border-radius: 8px;
  background: var(--text);
  color: #000;
  font-weight: 600;
  text-decoration: none;
}
.skip:focus-visible { top: 12px; }

.wrap {
  width: 100%;
  max-width: calc(var(--max) + 2 * var(--gutter));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* Top bar */

.bar {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(0, 0, 0, .78);
  border-bottom: 1px solid var(--line);
  -webkit-backdrop-filter: saturate(140%) blur(14px);
  backdrop-filter: saturate(140%) blur(14px);
}

.bar-in {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 1.0625rem;
  letter-spacing: -.02em;
  text-decoration: none;
}

.brand-mark {
  width: 22px;
  height: 22px;
  color: var(--text);
}
.brand-caret { fill: var(--accent); }

/* Buttons */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 26px;
  border-radius: 999px;
  background: var(--text);
  color: #000;
  font-weight: 600;
  font-size: 1rem;
  letter-spacing: -.01em;
  text-decoration: none;
  transition: background-color .15s ease;
}
.btn:hover { background: #fff; }
.btn:focus-visible { border-radius: 999px; }

.btn-sm {
  min-height: 36px;
  padding: 0 18px;
  font-size: .9375rem;
}

.btn-lg {
  min-height: 52px;
  padding: 0 32px;
  font-size: 1.0625rem;
}

/* Hero */

.hero {
  padding-top: clamp(64px, 9.5vw, 128px);
}

h1 {
  font-size: clamp(2.25rem, .9rem + 5.6vw, 5.75rem);
  font-weight: 600;
  line-height: 1;
  letter-spacing: -.045em;
  max-width: 14ch;
}

.caret {
  display: inline-block;
  width: .42em;
  height: .8em;
  margin-left: .08em;
  vertical-align: -.04em;
  border-radius: 2px;
  background: var(--accent);
  animation: blink 1.1s steps(1, end) 1.4s 3;
}

@keyframes blink {
  0%, 55% { opacity: 1; }
  56%, 100% { opacity: 0; }
}

.hero-foot {
  display: grid;
  gap: clamp(28px, 3vw, 36px);
  margin-top: clamp(28px, 3.6vw, 44px);
}

.lede {
  max-width: 58ch;
  color: var(--text-2);
  font-size: clamp(1.0625rem, 1rem + .3vw, 1.25rem);
  line-height: 1.55;
  letter-spacing: -.005em;
}

.cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 22px;
}

.private {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font-size: .9375rem;
}

.lock {
  width: 16px;
  height: 16px;
  flex: none;
}

/* Editor panel */

.ide {
  margin-top: clamp(56px, 8vw, 104px);
}

.win {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--s1);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .06);
  font-family: var(--mono);
  font-size: .8125rem;
  line-height: 1.7;
}

.win-bar {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  height: 40px;
  padding: 0 14px;
  border-bottom: 1px solid var(--line);
  background: var(--s2);
}

.dots { display: inline-flex; gap: 7px; }
.dots i {
  width: 11px;
  height: 11px;
  border: 1px solid rgba(255, 255, 255, .2);
  border-radius: 50%;
}

.win-title { color: var(--muted); }

.win-tag {
  justify-self: end;
  padding: 1px 9px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: .75rem;
}

.win-body {
  display: grid;
  grid-template-columns: 1fr;
}

.pane-h {
  color: var(--dim);
  font-size: .75rem;
  margin-bottom: 10px;
}

/* Explorer */

.tree {
  display: none;
  padding: 18px 16px;
  border-right: 1px solid var(--line);
}

.tree-list { color: var(--text-2); }

.tree-list > li { position: relative; padding-left: 2ch; }

.tree-list .dir::before {
  content: "";
  position: absolute;
  left: .35ch;
  top: .62em;
  width: 5px;
  height: 5px;
  border-right: 1.5px solid var(--dim);
  border-bottom: 1.5px solid var(--dim);
  transform: rotate(-45deg);
}
.tree-list .dir.is-open::before {
  top: .5em;
  transform: rotate(45deg);
}

.tree-list ul {
  margin: 2px 0 6px -1.3ch;
  padding-left: 1.6ch;
  border-left: 1px solid var(--line);
}

.seat {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1ch;
  padding-left: 1ch;
  color: var(--text);
}

.seat::after {
  content: "";
  flex: none;
  width: 7px;
  height: 7px;
  border: 1px solid var(--muted);
  border-radius: 50%;
}
.seat.is-on::after {
  border-color: var(--accent);
  background: var(--accent);
}

.legend {
  display: flex;
  gap: 2ch;
  margin-top: 22px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  color: var(--dim);
  font-size: .75rem;
}
.legend span { display: inline-flex; align-items: center; gap: 7px; }
.legend span::before {
  content: "";
  width: 7px;
  height: 7px;
  border: 1px solid var(--muted);
  border-radius: 50%;
}
.legend .lg-on::before { border-color: var(--accent); background: var(--accent); }

/* Log */

.main {
  min-width: 0;
  padding-bottom: 14px;
}

.tabs {
  display: flex;
  border-bottom: 1px solid var(--line);
  color: var(--dim);
}

.tab {
  padding: 8px 16px;
  border-right: 1px solid var(--line);
}
.tab.is-active {
  color: var(--text);
  background: var(--s1);
  box-shadow: inset 0 -1px 0 var(--accent);
}

.log { padding: 12px 0 6px; counter-reset: ln; }

.log li {
  position: relative;
  padding: 5px 16px 5px calc(14px + 4.5ch);
  border-left: 2px solid transparent;
  counter-increment: ln;
}

.log li::before {
  content: counter(ln);
  position: absolute;
  left: 12px;
  width: 3ch;
  color: var(--dim);
  text-align: right;
}

.who {
  margin-right: 1ch;
  color: var(--text);
  font-weight: 500;
}

.what {
  color: var(--text-2);
  overflow-wrap: anywhere;
}

.what q { color: var(--accent); }

.st {
  display: block;
  width: fit-content;
  margin: 4px 0 1px;
  padding: 0 8px;
  border-radius: 5px;
  font-size: .75rem;
  line-height: 1.75;
}
.st-wait {
  border: 1px solid var(--line);
  color: var(--muted);
}
.st-done {
  border: 1px solid rgba(185, 166, 255, .35);
  background: var(--accent-soft);
  color: var(--accent);
}

.log li.log-opt { display: none; }

.log li.is-hl {
  background: var(--accent-soft);
  border-left-color: var(--accent);
}

.prompt {
  display: flex;
  align-items: center;
  gap: 1ch;
  margin: 6px 16px 0 14px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  color: var(--muted);
}
.ps { color: var(--accent); }

.caret-sm {
  width: .6em;
  height: 1.15em;
  margin-left: 0;
  vertical-align: middle;
  border-radius: 1px;
  opacity: .7;
  animation: none;
}

/* Inspector */

.insp {
  display: none;
  padding: 18px 18px;
  border-left: 1px solid var(--line);
  background: rgba(255, 255, 255, .015);
}

.insp-title {
  margin-bottom: 14px;
  color: var(--text);
  font-family: var(--sans);
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: -.01em;
}

.kv { margin-bottom: 22px; }
.kv div {
  display: grid;
  grid-template-columns: 7ch 1fr;
  gap: 1ch;
  padding: 6px 0;
  border-top: 1px solid var(--line);
}
.kv dt { color: var(--dim); }
.kv dd { color: var(--text-2); }

.states {
  position: relative;
  color: var(--muted);
}
.states li {
  position: relative;
  padding: 3px 0 3px 22px;
}
.states li::before {
  content: "";
  position: absolute;
  left: 3px;
  top: .72em;
  width: 7px;
  height: 7px;
  border: 1px solid var(--muted);
  border-radius: 50%;
  background: var(--bg);
}
.states li::after {
  content: "";
  position: absolute;
  left: 6px;
  top: calc(.72em + 9px);
  height: calc(100% - 10px);
  width: 1px;
  background: var(--line);
}
.states li:last-child::after { display: none; }
.states .is-now { color: var(--accent); }
.states .is-now::before {
  border-color: var(--accent);
  background: var(--accent);
}

figcaption {
  margin-top: 14px;
  color: var(--muted);
  font-size: .875rem;
}

/* Structure */

.structure {
  display: grid;
  gap: 40px;
  padding-top: clamp(96px, 13vw, 176px);
  padding-bottom: clamp(72px, 9vw, 120px);
}

h2 {
  max-width: 16ch;
  font-size: clamp(1.875rem, 1.2rem + 2.4vw, 3rem);
  font-weight: 600;
  line-height: 1.06;
  letter-spacing: -.035em;
}

.structure-head p {
  max-width: 40ch;
  margin-top: 20px;
  color: var(--muted);
  font-size: 1.0625rem;
}

.terms { border-bottom: 1px solid var(--line); }

.terms div {
  display: grid;
  gap: 6px;
  padding: 22px 0;
  border-top: 1px solid var(--line);
}

.terms dt {
  font-family: var(--mono);
  font-size: .9375rem;
  color: var(--text);
}
.sl { color: var(--accent); }

.terms dd {
  max-width: 54ch;
  color: var(--text-2);
  font-size: 1.0625rem;
  line-height: 1.55;
}

.terms .rule {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 12px;
  color: var(--text-2);
  font-family: var(--mono);
  font-size: .8125rem;
  line-height: 1.5;
}
.terms .rule::before {
  content: "";
  flex: none;
  width: 24px;
  height: 1px;
  background: var(--accent);
}

/* Closing band */

.fecho {
  border-top: 1px solid var(--line);
  background: var(--s1-solid);
}

.fecho-in {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 32px;
  padding-top: clamp(64px, 7vw, 96px);
  padding-bottom: clamp(64px, 7vw, 96px);
}

.fecho-text p {
  max-width: 46ch;
  margin-top: 18px;
  color: var(--muted);
  font-size: 1.0625rem;
}

/* Not found */

.lost {
  padding-top: clamp(80px, 12vw, 168px);
  padding-bottom: clamp(96px, 14vw, 200px);
}

.lost-code {
  margin-bottom: 20px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: .9375rem;
}

.lost .lede { margin-top: clamp(24px, 3vw, 32px); }
.lost .btn { margin-top: clamp(32px, 4vw, 44px); }

/* Footer */

.foot { border-top: 1px solid var(--line); }

.foot-in {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px 24px;
  padding-top: 28px;
  padding-bottom: 36px;
  color: var(--muted);
  font-size: .875rem;
}

.foot-name {
  display: inline-flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 14px;
}

.foot-brand {
  color: var(--text);
  font-weight: 600;
  letter-spacing: -.02em;
}

.foot-etym {
  color: var(--muted);
  font-family: var(--mono);
  font-size: .8125rem;
}

/* Breakpoints */

@media (min-width: 560px) {
  .log li {
    display: grid;
    grid-template-columns: 3ch 14ch 1fr;
    column-gap: 1.5ch;
    padding: 2px 16px 2px 14px;
  }
  .log li.log-opt { display: grid; }
  .log li::before {
    position: static;
    width: auto;
    grid-row: 1 / span 2;
  }
  .who { grid-column: 2; margin-right: 0; }
  .what { grid-column: 3; }
  .st { grid-column: 3; justify-self: start; margin: 3px 0 2px; }
}

@media (min-width: 760px) {
  .win-body { grid-template-columns: 230px minmax(0, 1fr); }
  .tree { display: block; }
}

@media (min-width: 900px) {
  .structure {
    grid-template-columns: 5fr 7fr;
    gap: 64px;
  }
  .structure-head {
    position: sticky;
    top: 84px;
    align-self: start;
    padding-top: 22px;
  }
  .structure-head h2 { max-width: 12ch; }
  .terms div {
    grid-template-columns: 9.5rem 1fr;
    gap: 1.5rem;
  }
  .fecho-in {
    flex-direction: row;
    align-items: flex-end;
    justify-content: space-between;
    gap: 48px;
  }
  .fecho-in .btn-lg { flex: none; }
}

@media (min-width: 1240px) {
  .structure { grid-template-columns: 4fr 8fr; }
  .win-body { grid-template-columns: 230px minmax(0, 1fr) 280px; }
  .insp { display: block; }
  .log li { grid-template-columns: 3ch 14ch 1fr auto; }
  .st { grid-column: 4; grid-row: 1; margin: 0 0 0 1ch; align-self: center; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation: none !important;
    transition: none !important;
  }
}