/* ==========================================================================
   CAN Brewery — craft-can label × electrical schematic
   Warm paper, screen-print ink, beer amber. No gradients, no glow, no glass.
   ========================================================================== */

:root {
  --paper:      oklch(96.5% 0.017 84);
  --paper-deep: oklch(92.5% 0.028 82);
  --ink:        oklch(25% 0.021 55);
  --ink-soft:   oklch(42% 0.024 55);
  --amber:      oklch(74% 0.135 70);
  --amber-deep: oklch(56% 0.125 55);
  --line:       color-mix(in oklab, var(--ink) 20%, transparent);
  --line-strong: color-mix(in oklab, var(--ink) 45%, transparent);

  --font-display: "Anton", "Arial Narrow", sans-serif;
  --font-body: "Archivo", "Helvetica Neue", sans-serif;

  --measure: 34rem;
  --pad-x: clamp(1.25rem, 5vw, 4.5rem);
}

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { margin: 0; }
p, dl, dd, ol, ul { margin: 0; }
ol, ul { padding: 0; list-style: none; }
a { color: inherit; }
img { max-width: 100%; display: block; }

::selection { background: var(--amber); color: var(--ink); }

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5em;
  padding: 0.8em 1.5em;
  border: 2px solid var(--ink);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.02em;
  text-decoration: none;
  transition: transform 0.18s cubic-bezier(0.22, 1, 0.36, 1),
              box-shadow 0.18s cubic-bezier(0.22, 1, 0.36, 1),
              background-color 0.18s ease;
}

.btn:hover { transform: translate(-2px, -2px); box-shadow: 4px 4px 0 var(--ink); }
.btn:active { transform: translate(0, 0); box-shadow: 0 0 0 var(--ink); }
.btn:focus-visible { outline: 3px solid var(--amber-deep); outline-offset: 3px; }

.btn--solid { background: var(--ink); color: var(--paper); }
.btn--solid:hover { background: var(--ink); }
.btn--ghost { background: transparent; color: var(--ink); }
.btn--amber { background: var(--amber); color: var(--ink); border-color: var(--ink); }
.btn--small { padding: 0.5em 1em; font-size: 0.85rem; }

/* Flat two-tone link-out arrow: the shaft takes the button's own text color,
   the head takes whichever brand tone reads on that button's background. */
.btn__arrow {
  --arrow-accent: var(--amber-deep);
  flex: 0 0 auto;
  width: 1em;
  height: 1em;
  translate: 0 -0.06em;
}

.btn__arrow-shaft { stroke: currentColor; stroke-width: 2.4; fill: none; }
.btn__arrow-head { fill: var(--arrow-accent); }

.btn--amber .btn__arrow { --arrow-accent: var(--paper); }
.btn--solid .btn__arrow { --arrow-accent: var(--amber); }

/* --------------------------------------------------------------------------
   Header
   -------------------------------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  gap: clamp(1rem, 4vw, 3rem);
  padding: 0.85rem var(--pad-x);
  background: var(--paper);
  border-bottom: 2px solid var(--ink);
}

.wordmark {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  margin-right: auto;
}

.wordmark__mark { width: 2rem; height: auto; }

.wordmark__text {
  font-family: var(--font-display);
  font-size: 1.35rem;
  letter-spacing: 0.04em;
}

.wordmark__text em { font-style: normal; color: var(--amber-deep); }

.site-nav { display: flex; gap: clamp(0.9rem, 2.5vw, 2rem); }

.site-nav a {
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border-bottom: 2px solid transparent;
  padding-bottom: 0.1em;
}

.site-nav a:hover { border-bottom-color: var(--amber-deep); }

/* --------------------------------------------------------------------------
   Hero
   -------------------------------------------------------------------------- */

.hero {
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
  align-items: center;
  gap: clamp(2rem, 6vw, 6rem);
  padding: clamp(3.5rem, 9vh, 7rem) var(--pad-x) clamp(3rem, 8vh, 6rem);
  background-image: radial-gradient(color-mix(in oklab, var(--ink) 14%, transparent) 1px, transparent 1px);
  background-size: 26px 26px;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.55em;
  padding: 0.35em 0.9em;
  border: 1.5px solid var(--ink);
  border-radius: 999px;
  background: var(--paper);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.tag__dot {
  width: 0.5em;
  height: 0.5em;
  border-radius: 50%;
  background: var(--amber-deep);
}

.hero__title {
  font-family: var(--font-display);
  font-size: clamp(3.2rem, 9.5vw, 7.5rem);
  line-height: 0.98;
  letter-spacing: 0.01em;
  text-transform: uppercase;
  margin-top: 1.4rem;
}

.hero__accent {
  color: var(--amber-deep);
  -webkit-text-stroke: 0;
}

.hero__sub {
  max-width: var(--measure);
  margin-top: 1.6rem;
  font-size: 1.15rem;
  color: var(--ink-soft);
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  margin-top: 2.2rem;
}

.hero__art { justify-self: center; text-align: center; }

.hero__sticker {
  width: clamp(13rem, 26vw, 20rem);
  padding: clamp(1.6rem, 3vw, 2.6rem) clamp(1.2rem, 2.4vw, 2rem);
  background: var(--amber);
  border: 3px solid var(--ink);
  border-radius: 22% / 15%;
  rotate: -3.5deg;
  box-shadow: 8px 8px 0 color-mix(in oklab, var(--ink) 88%, transparent);
}

.hero__mascot { width: 100%; height: auto; }

.hero__caption {
  margin-top: 1.4rem;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

/* --------------------------------------------------------------------------
   Marquee
   -------------------------------------------------------------------------- */

.marquee {
  overflow: hidden;
  border-top: 2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  padding: 0.7rem 0;
}

.marquee__track {
  display: flex;
  width: max-content;
  /* JS measures one group and overrides both values so the strip scrolls at a
     constant speed and wraps seamlessly on any viewport. The fallbacks below
     hold up without JS, where the track is exactly two groups. */
  animation: marquee var(--marquee-duration, 28s) linear infinite;
  will-change: transform;
}

.marquee__group {
  flex: 0 0 auto;
  white-space: nowrap;
  font-family: var(--font-display);
  font-size: 1.05rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding-right: 0.75em;
}

.marquee__group i { font-style: normal; color: var(--amber); padding: 0 0.6em; }

@keyframes marquee {
  from { transform: translateX(0); }
  to   { transform: translateX(calc(-1 * var(--marquee-shift, 50%))); }
}

/* --------------------------------------------------------------------------
   Section scaffolding
   -------------------------------------------------------------------------- */

.section-label {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--amber-deep);
}

.section-label::after {
  content: "";
  display: inline-block;
  width: 3.5rem;
  height: 2px;
  background: var(--amber-deep);
  margin-left: 0.9rem;
  vertical-align: middle;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 5vw, 3.6rem);
  line-height: 1.04;
  text-transform: uppercase;
  letter-spacing: 0.01em;
  margin-top: 1rem;
}

.section-intro {
  max-width: var(--measure);
  margin-top: 1.2rem;
  color: var(--ink-soft);
}

/* --------------------------------------------------------------------------
   Topology
   -------------------------------------------------------------------------- */

.topology { padding: clamp(4rem, 10vh, 7.5rem) var(--pad-x) clamp(3rem, 8vh, 6rem); }

.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.8rem, 4vw, 3.5rem);
  margin-top: clamp(2.5rem, 6vh, 4.5rem);
}

.step:nth-child(2) { translate: 0 clamp(0.5rem, 2.5vw, 2.5rem); }
.step:nth-child(3) { translate: 0 clamp(1rem, 5vw, 5rem); }

.step__num {
  font-family: var(--font-display);
  font-size: 2.4rem;
  color: transparent;
  -webkit-text-stroke: 1.5px var(--amber-deep);
}

.step__title {
  font-family: var(--font-display);
  font-size: 1.5rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin: 0.5rem 0 0.6rem;
}

.step p { color: var(--ink-soft); max-width: 24rem; }

/* --------------------------------------------------------------------------
   Hardware — the bus
   -------------------------------------------------------------------------- */

.hardware {
  padding: clamp(4rem, 10vh, 7.5rem) var(--pad-x);
  background: var(--paper-deep);
  border-top: 2px solid var(--ink);
}

.bus {
  display: grid;
  grid-template-columns: 4.5rem minmax(0, 1fr);
  gap: 0 clamp(1rem, 3vw, 2.5rem);
  margin-top: clamp(2.5rem, 6vh, 4rem);
  max-width: 62rem;
}

.bus__rail {
  display: flex;
  flex-direction: column;
  align-items: center;
  color: var(--ink);
}

.bus__term { width: 2.5rem; flex: none; }

.bus__wires {
  flex: 1;
  width: 14px;
  border-left: 2.5px solid var(--ink);
  border-right: 2.5px solid var(--ink);
}

.nodes { display: grid; gap: clamp(1.4rem, 3vh, 2.2rem); padding: 1.5rem 0; }

.node {
  position: relative;
  background: var(--paper);
  border: 2px solid var(--ink);
  padding: 1.5rem 1.7rem 1.4rem;
  box-shadow: 6px 6px 0 color-mix(in oklab, var(--ink) 14%, transparent);
}

/* stub connector from rail to card */
.node::before {
  content: "";
  position: absolute;
  top: 2.1rem;
  right: 100%;
  width: calc(clamp(1rem, 3vw, 2.5rem) + 1.6rem);
  height: 2.5px;
  background: var(--ink);
}

/* junction dot on the bus wire */
.node::after {
  content: "";
  position: absolute;
  top: calc(2.1rem - 4px);
  right: calc(100% + clamp(1rem, 3vw, 2.5rem) + 1.35rem);
  width: 10.5px;
  height: 10.5px;
  border-radius: 50%;
  background: var(--ink);
}

.node__head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.4rem 0.9rem;
}

.node__id {
  font-weight: 700;
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  padding: 0.2em 0.55em;
  background: var(--ink);
  color: var(--amber);
}

.node__name {
  font-family: var(--font-display);
  font-size: 1.6rem;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.node__status {
  margin-left: auto;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--amber-deep);
  border: 1.5px solid var(--amber-deep);
  border-radius: 999px;
  padding: 0.25em 0.8em;
  white-space: nowrap;
}

.node__status--open { color: var(--paper); background: var(--amber-deep); }

.node__desc { margin-top: 0.8rem; color: var(--ink-soft); max-width: 38rem; }

.node__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1rem;
}

.node__tags span {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 0.3em 0.7em;
  border: 1.5px solid var(--line-strong);
  color: var(--ink-soft);
}

.node--open { background: var(--paper-deep); border-style: dashed; box-shadow: none; }
.node--open::before { background: repeating-linear-gradient(90deg, var(--ink) 0 6px, transparent 6px 12px); }

/* --------------------------------------------------------------------------
   Why CAN
   -------------------------------------------------------------------------- */

.why {
  padding: clamp(4rem, 10vh, 7.5rem) var(--pad-x);
  border-top: 2px solid var(--ink);
}

.reasons {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(2.2rem, 5vw, 4rem) clamp(2.5rem, 6vw, 6rem);
  margin-top: clamp(2.5rem, 6vh, 4rem);
  max-width: 70rem;
}

.reason { border-top: 2px solid var(--ink); padding-top: 1.2rem; }

.reason dt {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  font-family: var(--font-display);
  font-size: 1.35rem;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.reason__num {
  font-size: 0.95rem;
  color: var(--amber-deep);
  letter-spacing: 0.1em;
  flex: none;
}

.reason dd { margin-top: 0.7rem; color: var(--ink-soft); }

/* --------------------------------------------------------------------------
   Open source
   -------------------------------------------------------------------------- */

.oss {
  background: var(--ink);
  color: var(--paper);
  border-top: 2px solid var(--ink);
}

.oss__inner {
  padding: clamp(4.5rem, 11vh, 8rem) var(--pad-x);
  background-image: radial-gradient(color-mix(in oklab, var(--paper) 12%, transparent) 1px, transparent 1px);
  background-size: 26px 26px;
}

.section-label--inverse { color: var(--amber); }
.section-label--inverse::after { background: var(--amber); }

.oss__title {
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 7vw, 5.5rem);
  line-height: 1.02;
  text-transform: uppercase;
  margin-top: 1rem;
}

.oss__accent { color: var(--amber); }

.oss__body {
  max-width: var(--measure);
  margin-top: 1.6rem;
  font-size: 1.1rem;
  color: color-mix(in oklab, var(--paper) 78%, var(--ink));
}

.oss__actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.4rem;
  margin-top: 2.4rem;
}

.oss .btn--amber:hover { box-shadow: 4px 4px 0 var(--amber-deep); }

.oss__note {
  font-size: 0.9rem;
  color: color-mix(in oklab, var(--paper) 60%, var(--ink));
  max-width: 20rem;
}

/* --------------------------------------------------------------------------
   Title-block footer (KiCad style)
   -------------------------------------------------------------------------- */

.titleblock {
  border-top: 2.5px solid var(--ink);
  background: var(--paper);
  padding: clamp(2rem, 5vh, 3.5rem) var(--pad-x) clamp(2.5rem, 6vh, 4rem);
}

.titleblock__grid {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 1.2fr) minmax(0, 0.6fr) minmax(0, 0.8fr) minmax(0, 0.7fr);
  border: 2.5px solid var(--ink);
  max-width: 72rem;
  margin-inline: auto;
}

.titleblock__cell {
  padding: 0.7rem 1rem 0.85rem;
  border-right: 1.5px solid var(--ink);
  min-width: 0;
}

.titleblock__cell:nth-child(5) { border-right: none; }

.titleblock__cell--title { grid-column: 1; }

.titleblock__cell--license {
  grid-column: 1 / -1;
  border-top: 1.5px solid var(--ink);
  border-right: none;
}

.titleblock__label {
  display: block;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--amber-deep);
}

.titleblock__value {
  display: block;
  margin-top: 0.2rem;
  font-weight: 600;
  font-size: 0.95rem;
  overflow-wrap: break-word;
}

.titleblock__value a { text-decoration-color: var(--amber-deep); text-underline-offset: 3px; }

/* --------------------------------------------------------------------------
   Reveal on scroll
   -------------------------------------------------------------------------- */

@media (prefers-reduced-motion: no-preference) {
  .reveal {
    opacity: 0;
    transform: translateY(1.2rem);
    transition: opacity 0.6s cubic-bezier(0.22, 1, 0.36, 1),
                transform 0.6s cubic-bezier(0.22, 1, 0.36, 1);
  }

  .reveal.in { opacity: 1; transform: none; }
}

@media (prefers-reduced-motion: reduce) {
  .marquee__track { animation: none; }
  html { scroll-behavior: auto; }
}

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */

@media (max-width: 56rem) {
  .hero { grid-template-columns: 1fr; }
  .hero__art { justify-self: start; display: flex; align-items: center; gap: 1.5rem; }
  .hero__sticker { width: clamp(9rem, 32vw, 13rem); }
  .hero__caption { margin-top: 0; text-align: left; }

  .steps { grid-template-columns: 1fr; }
  .step:nth-child(2), .step:nth-child(3) { translate: none; }

  .reasons { grid-template-columns: 1fr; }

  .titleblock__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .titleblock__cell { border-top: 1.5px solid var(--ink); }
  .titleblock__cell:nth-child(-n+2) { border-top: none; }
  .titleblock__cell--title { grid-column: 1 / -1; border-right: none; }
  .titleblock__cell:nth-child(2) { border-top: 1.5px solid var(--ink); }
  .titleblock__cell:nth-child(3) { border-right: none; }
  .titleblock__cell:nth-child(5) { border-right: 1.5px solid var(--ink); }
  .titleblock__cell--license { border-right: none; }
}

@media (max-width: 40rem) {
  .site-header { flex-wrap: wrap; row-gap: 0.6rem; }
  .site-nav { order: 3; width: 100%; }

  .bus { grid-template-columns: 2rem minmax(0, 1fr); }
  .bus__term { width: 1.8rem; }
  .bus__wires { width: 9px; border-left-width: 2px; border-right-width: 2px; }
  .node { padding: 1.2rem 1.1rem 1.1rem; }
  .node__status { margin-left: 0; }
}