@font-face { font-family: "Plex Sans"; src: url("fonts/ibm-plex-sans-latin-400-normal.woff2") format("woff2"); font-weight: 400; font-style: normal; font-display: swap; }
@font-face { font-family: "Plex Sans"; src: url("fonts/ibm-plex-sans-latin-400-italic.woff2") format("woff2"); font-weight: 400; font-style: italic; font-display: swap; }
@font-face { font-family: "Plex Sans"; src: url("fonts/ibm-plex-sans-latin-500-normal.woff2") format("woff2"); font-weight: 500; font-style: normal; font-display: swap; }
@font-face { font-family: "Plex Sans"; src: url("fonts/ibm-plex-sans-latin-600-normal.woff2") format("woff2"); font-weight: 600; font-style: normal; font-display: swap; }
@font-face { font-family: "Plex Mono"; src: url("fonts/ibm-plex-mono-latin-400-normal.woff2") format("woff2"); font-weight: 400; font-style: normal; font-display: swap; }
@font-face { font-family: "Plex Mono"; src: url("fonts/ibm-plex-mono-latin-500-normal.woff2") format("woff2"); font-weight: 500; font-style: normal; font-display: swap; }

:root {
  --bg:       #0D1015;
  --bg-2:     #12161D;
  --panel:    #151A22;
  --line:     #262D38;
  --line-2:   #36404E;
  --text:     #C9CFD8;
  --strong:   #EEF1F5;
  --muted:    #8791A0;
  --cobalt:   #3560F0;
  --cobalt-hi:#7F9DFF;

  --sans: "Plex Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: "Plex Mono", ui-monospace, Menlo, Consolas, monospace;

  --wrap: 72rem;
  --gutter: clamp(1.25rem, 5vw, 3rem);
  --col: 14rem;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 1.0625rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
h1, h2, h3, p, ol, ul { margin: 0; }
ol, ul { padding: 0; list-style: none; }
svg { display: block; max-width: 100%; height: auto; }
section[id] { scroll-margin-top: 1rem; }

a { color: var(--strong); text-decoration-color: var(--line-2); text-decoration-thickness: 1px; text-underline-offset: 0.22em; }
a:hover { color: var(--cobalt-hi); text-decoration-color: currentColor; }
a:focus-visible, .btn:focus-visible { outline: 2px solid var(--cobalt-hi); outline-offset: 3px; border-radius: 2px; }

.skip { position: absolute; left: -9999px; }
.skip:focus { left: var(--gutter); top: 0.75rem; background: var(--strong); color: var(--bg); padding: 0.5rem 0.75rem; z-index: 10; }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 var(--gutter); }

/* Header */
.site-head { border-bottom: 1px solid var(--line); }
.site-head .wrap { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 4.25rem; }
.mark { display: inline-flex; align-items: center; gap: 0.6rem; text-decoration: none; color: var(--strong); font-weight: 600; font-size: 1.05rem; letter-spacing: -0.01em; }
.mark:hover { color: var(--strong); }
.mark svg { width: 22px; height: 22px; flex: none; }
.nav { display: flex; align-items: center; gap: 1.75rem; font-size: 0.95rem; }
.nav a { text-decoration: none; color: var(--muted); }
.nav a:hover { color: var(--strong); }
.nav .btn { color: #fff; padding: 0.5rem 0.9rem; font-size: 0.92rem; }

/* Buttons and type */
.btn {
  display: inline-block;
  background: var(--cobalt);
  color: #fff;
  text-decoration: none;
  font-weight: 500;
  padding: 0.8rem 1.3rem;
  border-radius: 3px;
}
.btn:hover { background: #2A4FD6; color: #fff; }
.label { font-family: var(--sans); font-size: 0.92rem; font-weight: 500; letter-spacing: 0; color: var(--muted); }
.label .n { color: var(--cobalt-hi); }
h1, h2 { color: var(--strong); font-weight: 600; letter-spacing: -0.025em; }
h3 { color: var(--strong); font-weight: 600; font-size: 1.15rem; letter-spacing: -0.01em; line-height: 1.3; }

/* Hero */
.hero { padding: clamp(3.5rem, 9vw, 6.5rem) 0 clamp(3rem, 6vw, 4.5rem); }
.hero h1 { font-size: clamp(2.4rem, 6.4vw, 4.6rem); line-height: 1.02; max-width: 20ch; text-wrap: balance; }
.hero .lede { margin-top: 1.6rem; font-size: clamp(1.1rem, 2vw, 1.28rem); line-height: 1.55; max-width: 40rem; }
.actions { margin-top: 2.25rem; display: flex; flex-wrap: wrap; gap: 0.9rem 1.75rem; align-items: center; }
.text-link { font-weight: 500; }

/* Diagram */
.diagram { margin-top: clamp(3rem, 7vw, 4.5rem); padding-top: 2rem; border-top: 1px solid var(--line); }
.diagram figcaption { margin-bottom: 1.5rem; }
.diagram .v { display: none; max-width: 24rem; }
.dg-box { fill: var(--bg-2); stroke: var(--line-2); stroke-width: 1; }
.dg-trace { fill: none; stroke: var(--muted); stroke-width: 1.5; }
.dg-live { fill: none; stroke: var(--cobalt-hi); stroke-width: 1.5; }
.dg-loop { fill: none; stroke: var(--line-2); stroke-width: 1.25; stroke-dasharray: 4 5; }
.dg-head { font-family: var(--mono); font-size: 12px; letter-spacing: 0.06em; fill: var(--muted); }
.dg-num { font-family: var(--mono); font-size: 12px; fill: var(--cobalt-hi); }
.dg-item { font-family: var(--sans); font-size: 15px; fill: var(--strong); }
.dg-sub { font-family: var(--sans); font-size: 13px; fill: var(--muted); }
.dg-note { font-family: var(--mono); font-size: 11.5px; letter-spacing: 0.03em; fill: var(--muted); }
.dg-out { fill: var(--cobalt); }
.dg-out-t { font-family: var(--sans); font-size: 15px; font-weight: 600; fill: #fff; }
.dg-out-s { font-family: var(--sans); font-size: 13px; fill: #DCE4FF; }
.dg-chan { fill: var(--panel); stroke: var(--line-2); stroke-width: 1; }
.dg-port { fill: var(--bg); stroke: var(--muted); stroke-width: 1.5; }
.dg-arrow { fill: var(--muted); }

/* Sections */
.section { padding: clamp(3.5rem, 8vw, 6rem) 0; border-top: 1px solid var(--line); }
.section.alt { background: var(--bg-2); }
.section-head { display: grid; grid-template-columns: var(--col) 1fr; gap: 1rem 3rem; margin-bottom: clamp(2rem, 5vw, 3rem); }
.section-head > .label { grid-column: 1; grid-row: 1 / span 2; padding-top: 0.7rem; }
.section-head h2 { grid-column: 2; font-size: clamp(1.8rem, 3.8vw, 2.7rem); line-height: 1.1; max-width: 22ch; text-wrap: balance; }
.section-head p:not(.label) { grid-column: 2; max-width: 42rem; }
.indent { margin-left: calc(var(--col) + 3rem); }

/* Layers */
.layers > li { display: grid; grid-template-columns: var(--col) 1fr; gap: 0.75rem 3rem; padding: 2rem 0; border-top: 1px solid var(--line); }
.layers > li:last-child { border-bottom: 1px solid var(--line); }
.layers .label { padding-top: 0.25rem; }
.layers p { margin-top: 0.6rem; max-width: 44rem; }
.layers .covers { margin-top: 1rem; font-family: var(--mono); font-size: 0.8rem; letter-spacing: 0.02em; color: var(--muted); max-width: 44rem; line-height: 1.7; }

/* Fit */
.fit { display: grid; grid-template-columns: 1fr 1fr; gap: 2.5rem; max-width: 54rem; }
.fit h3 { font-size: 1rem; margin-bottom: 0.75rem; }
.fit li { padding: 0.8rem 0; border-top: 1px solid var(--line); }
.fit li:last-child { border-bottom: 1px solid var(--line); }
.fit li strong { color: var(--strong); font-weight: 500; }
.fit .no h3 { color: var(--muted); }

/* Timeline */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0 2.5rem; border-top: 1px solid var(--line-2); }
.steps li { position: relative; padding-top: 1.5rem; }
.steps li::before { content: ""; position: absolute; top: -5px; left: 0; width: 9px; height: 9px; background: var(--bg-2); border: 1.5px solid var(--muted); }
.steps li:last-child::before { background: var(--cobalt); border-color: var(--cobalt); }
.steps .when { font-size: 0.9rem; font-weight: 500; color: var(--cobalt-hi); }
.steps h3 { margin-top: 0.3rem; }
.steps ul { margin-top: 0.75rem; }
.steps ul li { padding: 0.3rem 0; }
.steps ul li::before { display: none; }
.handoff { margin-top: clamp(2.5rem, 5vw, 3.5rem); padding-top: 1.75rem; border-top: 1px solid var(--line); display: grid; grid-template-columns: var(--col) 1fr; gap: 1rem 3rem; }
.handoff p { max-width: 44rem; }
.handoff p strong { color: var(--strong); font-weight: 500; }
.handoff p + p { margin-top: 0.75rem; color: var(--muted); }
.handoff .label { grid-row: 1 / span 2; padding-top: 0.25rem; }
.handoff p:not(.label) { grid-column: 2; }

/* Founder note */
.section-head.note { margin-bottom: 0; }
.section-head .note-body { grid-column: 2; grid-row: 1 / span 2; max-width: 42rem; }
.note-body p { font-size: clamp(1.1rem, 1.8vw, 1.22rem); line-height: 1.6; color: var(--strong); }
.note-body p + p { margin-top: 1.1rem; }
.sign { margin-top: 1.75rem; display: flex; flex-wrap: wrap; align-items: baseline; gap: 0.5rem 1.5rem; }
.sign .who { color: var(--strong); font-weight: 600; }
.sign .who span { color: var(--muted); font-weight: 400; }

/* CTA */
.cta { padding: clamp(4rem, 9vw, 6.5rem) 0; border-top: 1px solid var(--line); }
.cta h2 { font-size: clamp(2rem, 4.6vw, 3.2rem); line-height: 1.06; max-width: 24ch; text-wrap: balance; }
.cta p { margin-top: 1.25rem; max-width: 38rem; }
.cta .alt-contact { margin-top: 1.25rem; font-size: 0.95rem; color: var(--muted); }

/* Footer */
.site-foot { border-top: 1px solid var(--line); background: var(--bg-2); color: var(--muted); font-size: 0.95rem; }
.foot-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 2rem 3rem; padding: clamp(3rem, 6vw, 4rem) 0 2.5rem; }
.foot-brand p { margin-top: 1rem; max-width: 22rem; }
.foot-brand .btn { margin-top: 1.5rem; }
.foot-col { display: flex; flex-direction: column; gap: 0.55rem; }
.foot-h { color: var(--strong); font-weight: 600; margin-bottom: 0.35rem; }
.foot-col a { color: var(--text); text-decoration: none; }
.foot-col a:hover { color: var(--strong); }
.foot-base { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 0.5rem 2rem; padding: 1.25rem 0 1.75rem; border-top: 1px solid var(--line); font-size: 0.88rem; }
@media (max-width: 52rem) { .foot-grid { grid-template-columns: 1fr 1fr; } .foot-brand { grid-column: 1 / -1; } }

/* Legal */
.legal { padding: clamp(3rem, 8vw, 5rem) 0 clamp(4rem, 9vw, 6rem); }
.legal .wrap { max-width: 46rem; }
.legal h1 { font-size: clamp(2rem, 5vw, 2.75rem); line-height: 1.1; }
.legal .updated { margin-top: 0.75rem; }
.legal h2 { font-size: 1.3rem; margin-top: 2.5rem; letter-spacing: -0.01em; }
.legal p, .legal ul { margin-top: 0.9rem; }
.legal ul { padding-left: 1.2rem; list-style: disc; }
.legal li + li { margin-top: 0.35rem; }
.legal strong { color: var(--strong); font-weight: 500; }

/* Responsive */
@media (max-width: 56rem) {
  .section-head, .layers > li, .handoff { grid-template-columns: 1fr; }
  .section-head > .label, .section-head h2, .section-head p:not(.label), .section-head .note-body, .handoff .label, .handoff p:not(.label) { grid-column: 1; grid-row: auto; padding-top: 0; }
  .indent { margin-left: 0; }
  .diagram .h { display: none; }
  .diagram .v { display: block; }
  .steps { grid-template-columns: 1fr; border-top: 0; border-left: 1px solid var(--line-2); margin-left: 4px; }
  .steps > li { padding: 0 0 1.75rem 1.5rem; }
  .steps > li:last-child { padding-bottom: 0; }
  .steps > li::before { top: 0.35rem; left: -5px; }
}
@media (max-width: 40rem) {
  .nav a:not(.btn) { display: none; }
  .fit { grid-template-columns: 1fr; gap: 2rem; }
}

/* v5 additions */
.diagram { margin-left: 0; margin-right: 0; margin-bottom: 0; }
.items { margin-top: 0.9rem; display: grid; grid-template-columns: 1fr 1fr; gap: 0 2.5rem; max-width: 50rem; }
.items li { padding: 0.55rem 0; border-top: 1px solid var(--line); }
.steps > li > p:not(.when) { margin-top: 0.4rem; }
.fitlist { max-width: 44rem; }
.fitlist li { padding: 0.85rem 0; border-top: 1px solid var(--line); color: var(--strong); }
.fitlist li:last-child { border-bottom: 1px solid var(--line); }
.faq { max-width: 46rem; margin-top: 0; margin-bottom: 0; margin-right: 0; }
.nav { gap: 1.5rem; }
@media (max-width: 60rem) { .nav a[href="/#faq"] { display: none; } }
@media (max-width: 56rem) { .items { grid-template-columns: 1fr; } }
#why .section-head { margin-bottom: 0; }

/* FAQ accordion */
.faq details { border-top: 1px solid var(--line); }
.faq details:last-child { border-bottom: 1px solid var(--line); }
.faq summary { list-style: none; cursor: pointer; display: flex; justify-content: space-between; align-items: baseline; gap: 1.5rem; padding: 1.15rem 0; color: var(--strong); font-weight: 600; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-weight: 400; font-size: 1.3rem; line-height: 1; color: var(--cobalt-hi); }
.faq details[open] summary::after { content: "\2212"; }
.faq summary:focus-visible { outline: 2px solid var(--cobalt-hi); outline-offset: 3px; }
.faq details p { padding: 0 2.5rem 1.25rem 0; }