/* charlesbrendon.net - Charles Brendon
   Research-brief aesthetic: cool slate ground, white data surfaces, violet signal accent,
   fixed left index rail, numbered sections, all-grotesque typography. */

:root {
  --ink: #0d1220;
  --ink-2: #59657d;
  --ink-3: #8b96ab;
  --bg: #eceff5;
  --surface: #ffffff;
  --line: #d3dae6;
  --line-2: #e3e8f0;
  --violet: #4a35d4;
  --violet-d: #33228f;
  --violet-t: #eceafb;
  --teal: #0e8f84;
  --on-dark: #e7ebf3;
  --on-dark-2: #9aa5bb;
  --dark-line: #262d40;
  --rail: 234px;
  --wrap: 1020px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation: none !important; transition: none !important; }
}

body {
  font-family: "Public Sans", system-ui, -apple-system, sans-serif;
  font-weight: 400;
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  overflow-wrap: break-word;
  font-family: "Archivo", system-ui, sans-serif;
  font-weight: 600;
  line-height: 1.14;
  letter-spacing: -0.022em;
}

a { color: var(--violet); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--violet-d); }
a:focus-visible { outline: 2px solid var(--violet); outline-offset: 3px; }

strong { font-weight: 600; }

.mono {
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.skip { position: absolute; left: -9999px; }
.skip:focus { left: 0.5rem; top: 0.5rem; z-index: 99; background: var(--ink); color: #fff; padding: 0.7rem 1.1rem; }

/* ============ FIXED INDEX RAIL ============ */
.rail {
  position: fixed; inset: 0 auto 0 0; width: var(--rail); z-index: 30;
  background: var(--surface);
  border-right: 1px solid var(--line);
  padding: 2.1rem 1.5rem 1.6rem;
  display: flex; flex-direction: column; gap: 2.2rem;
}
.mark { display: flex; gap: 0.75rem; align-items: flex-start; text-decoration: none; }
.mark .glyph {
  width: 38px; height: 38px; flex: none;
  background: var(--violet); color: #fff;
  display: grid; place-items: center;
  font-family: "Archivo", sans-serif; font-weight: 700; font-size: 0.95rem; letter-spacing: 0.02em;
}
.mark .who { line-height: 1.25; }
.mark .who b {
  display: block; font-family: "Archivo", sans-serif; font-weight: 600;
  font-size: 1rem; color: var(--ink); letter-spacing: -0.015em;
}
.mark .who span { display: block; font-size: 0.76rem; color: var(--ink-2); }

.rail nav { display: flex; flex-direction: column; }
.rail nav a {
  display: grid; grid-template-columns: 1.9rem 1fr; align-items: baseline; gap: 0.4rem;
  padding: 0.52rem 0; border-top: 1px solid var(--line-2);
  color: var(--ink); text-decoration: none;
  font-size: 0.9rem;
}
.rail nav a:last-child { border-bottom: 1px solid var(--line-2); }
.rail nav a i { font-style: normal; font-family: "DM Mono", monospace; font-size: 0.7rem; color: var(--ink-3); }
.rail nav a:hover { color: var(--violet); }
.rail nav a:hover i { color: var(--violet); }

.rail .rail-foot { margin-top: auto; font-size: 0.78rem; color: var(--ink-2); line-height: 1.6; }
.rail .rail-foot a { display: block; word-break: break-word; }

/* ============ PAGE ============ */
.page { margin-left: var(--rail); }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 2.5rem; }

/* ============ HERO ============ */
.hero { background: var(--surface); border-bottom: 1px solid var(--line); }
.hero .wrap { padding-top: 4.25rem; padding-bottom: 0; }
.hero .eyebrow { color: var(--violet); margin-bottom: 1.5rem; }
.hero .eyebrow em { font-style: normal; color: var(--ink-3); padding: 0 0.45rem; }
.hero h1 {
  font-size: clamp(2.1rem, 4.4vw, 3.2rem);
  max-width: 21ch;
  margin-bottom: 2rem;
}
.hero h1 span { color: var(--violet); }
.hero-body { display: grid; grid-template-columns: 1fr 320px; gap: 3rem; align-items: start; }
.hero-body .lede { font-size: 1.12rem; color: var(--ink-2); max-width: 40ch; }
.hero-body .lede + p { margin-top: 1.3rem; font-size: 0.98rem; color: var(--ink-2); }
.shot { position: relative; margin: 0; }
.shot::before {
  content: ""; position: absolute; left: -16px; top: 16px; right: 16px; bottom: -16px;
  border: 1px solid var(--violet); background: var(--violet-t);
}
.shot img { position: relative; display: block; width: 100%; height: auto; }

/* spec strip */
.spec {
  margin-top: 3.5rem;
  display: grid; grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--line);
}
.spec div { padding: 1.15rem 1.4rem 1.35rem 0; }
.spec div + div { padding-left: 1.4rem; border-left: 1px solid var(--line); }
.spec dt { color: var(--ink-3); margin-bottom: 0.4rem; }
.spec dd { font-size: 0.92rem; line-height: 1.45; }

/* ============ BANNER ============ */
.banner { position: relative; background: var(--ink); }
.banner img {
  display: block; width: 100%; height: clamp(220px, 26vw, 340px);
  object-fit: cover; object-position: 50% 62%;
  opacity: 0.72;
}
.banner .over {
  position: absolute; inset: auto 0 0 0;
  background: linear-gradient(0deg, rgba(13,18,32,0.94) 0%, rgba(13,18,32,0.55) 55%, transparent 100%);
  padding: 3.5rem 0 1.9rem;
}
.banner .over .wrap { display: flex; align-items: flex-end; justify-content: space-between; gap: 2rem; flex-wrap: wrap; }
.banner p {
  color: #fff; font-family: "Archivo", sans-serif; font-weight: 500;
  font-size: clamp(1.05rem, 2.1vw, 1.45rem); line-height: 1.3; letter-spacing: -0.015em;
  max-width: 30ch;
}
.banner .cap { color: var(--on-dark-2); flex: none; }

/* grid children must be allowed to shrink below min-content */
.hero-body > *, .band-grid > *, .policy-grid > *, .contact .wrap > *,
.spec > div, .datasheet > div, .rows .r > *, .threads > li > * { min-width: 0; }

/* ============ SECTIONS ============ */
.sec { padding: 4.5rem 0; }
.sec.on-white { background: var(--surface); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.sec-head { margin-bottom: 2.5rem; }
.sec-head .idx { color: var(--violet); display: block; margin-bottom: 0.7rem; }
.sec-head h2 { font-size: clamp(1.6rem, 3vw, 2.15rem); max-width: 26ch; }
.sec-head .sub { margin-top: 1rem; color: var(--ink-2); max-width: 56ch; }

/* about */
.prose { max-width: 62ch; }
.prose p + p { margin-top: 1.15rem; }
.datasheet {
  margin-top: 3rem;
  display: grid; grid-template-columns: repeat(4, 1fr);
  border: 1px solid var(--line); background: var(--surface);
}
.datasheet > div { padding: 1.3rem 1.35rem; }
.datasheet > div + div { border-left: 1px solid var(--line); }
.datasheet dt { color: var(--ink-3); margin-bottom: 0.45rem; }
.datasheet dd { font-size: 0.94rem; line-height: 1.5; }

/* statement */
.statement {
  border-left: 4px solid var(--violet);
  padding: 0.15rem 0 0.15rem 1.6rem;
  margin-bottom: 2.75rem;
  max-width: 46ch;
}
.statement p {
  font-family: "Archivo", sans-serif; font-weight: 500;
  font-size: clamp(1.15rem, 2.3vw, 1.5rem); line-height: 1.32; letter-spacing: -0.018em;
}
.statement .src { display: block; margin-top: 0.85rem; color: var(--ink-3); }

/* numbered rows */
.rows { border-top: 1px solid var(--line); }
.rows > li { list-style: none; border-bottom: 1px solid var(--line); }
.rows .r {
  display: grid; grid-template-columns: 4.5rem 15rem 1fr; gap: 1.5rem;
  padding: 1.6rem 0.9rem 1.7rem 0;
}
.rows .n { font-family: "DM Mono", monospace; font-size: 1.5rem; color: var(--violet); line-height: 1.1; }
.rows h3 { font-size: 1.16rem; padding-top: 0.15rem; }
.rows p { color: var(--ink-2); font-size: 0.98rem; }

/* ============ DARK BAND ============ */
.band { background: var(--ink); color: var(--on-dark); padding: 4.75rem 0; }
.band h2, .band h3 { color: #fff; }
.band .sec-head .idx { color: #a99cf6; }
.band .sec-head .sub { color: var(--on-dark-2); }
.band-grid { display: grid; grid-template-columns: 15rem 1fr; gap: 3rem; }
.band-grid > .lead h2 { font-size: clamp(1.5rem, 2.7vw, 2rem); }
.band-grid > .lead .idx { color: #a99cf6; display: block; margin-bottom: 0.7rem; }
.pillars { border-top: 1px solid var(--dark-line); }
.pillars > li { list-style: none; border-bottom: 1px solid var(--dark-line); padding: 1.5rem 0 1.6rem; }
.pillars .top { display: flex; align-items: baseline; gap: 0.9rem; margin-bottom: 0.5rem; }
.pillars .top span { font-family: "DM Mono", monospace; font-size: 0.8rem; color: #a99cf6; letter-spacing: 0.08em; min-width: 1.9rem; }
.pillars h3 { font-size: 1.2rem; }
.pillars p { color: var(--on-dark-2); font-size: 0.97rem; max-width: 68ch; }

/* figure 1 diagram */
.fig { margin: 3.25rem 0 0; }
.fig .frame { border: 1px solid var(--dark-line); background: #101728; padding: 1.6rem 1.4rem 1.1rem; overflow-x: auto; -webkit-overflow-scrolling: touch; }
.fig svg { display: block; width: 100%; min-width: 380px; height: auto; }
.fig figcaption { margin-top: 0.9rem; color: var(--on-dark-2); text-transform: none; letter-spacing: 0.02em; font-size: 0.78rem; line-height: 1.5; }
.fig figcaption b { color: #a99cf6; font-weight: 500; }

/* ============ POLICY ============ */
.policy-grid { display: grid; grid-template-columns: 380px 1fr; gap: 3rem; align-items: start; }
.plate { margin: 0; }
.plate .frame { border: 1px solid var(--line); background: var(--surface); padding: 0.7rem; }
.plate img { display: block; width: 100%; height: auto; }
.plate figcaption { margin-top: 0.8rem; color: var(--ink-2); text-transform: none; letter-spacing: 0.02em; font-size: 0.78rem; line-height: 1.5; }
.plate figcaption b { color: var(--violet); font-weight: 500; }

.threads { display: grid; gap: 0; }
.threads > li {
  list-style: none;
  display: grid; grid-template-columns: 24px 1fr; gap: 1rem;
  padding: 1.1rem 0; border-bottom: 1px solid var(--line);
}
.threads > li:first-child { border-top: 1px solid var(--line); }
.threads .ico { width: 22px; height: 22px; margin-top: 0.3rem; stroke: var(--violet); fill: none; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.threads h3 { font-size: 1.05rem; margin-bottom: 0.15rem; }
.threads p { color: var(--ink-2); font-size: 0.95rem; }

/* ============ CONTACT ============ */
.contact { background: var(--violet); color: #fff; padding: 4rem 0; }
.contact .wrap { display: grid; grid-template-columns: 15rem 1fr; gap: 3rem; align-items: center; }
.contact .idx { color: #c8bffa; display: block; margin-bottom: 0.6rem; }
.contact h2 { color: #fff; font-size: clamp(1.5rem, 2.7vw, 2rem); }
.contact p { color: #d8d2fb; margin-bottom: 1.1rem; max-width: 46ch; }
.contact .addr {
  display: inline-block;
  font-family: "Archivo", sans-serif; font-weight: 600;
  font-size: clamp(1.25rem, 3.1vw, 1.95rem); letter-spacing: -0.02em;
  color: #fff; text-decoration: none;
  border-bottom: 2px solid rgba(255,255,255,0.45);
  padding-bottom: 0.12rem;
}
.contact .addr:hover { color: #fff; border-bottom-color: #fff; }
.contact .alt { margin: 1.4rem 0 0; color: #d8d2fb; font-size: 0.95rem; }
.contact .alt a { color: #fff; }

/* ============ FOOTER ============ */
.foot { background: var(--ink); color: var(--on-dark-2); padding: 1.9rem 0 2.2rem; font-size: 0.85rem; }
.foot .wrap { display: flex; justify-content: space-between; gap: 1.2rem; flex-wrap: wrap; }
.foot a { color: var(--on-dark); }

/* ============ RESPONSIVE ============ */
@media (max-width: 1080px) {
  .rail {
    position: sticky; inset: 0 0 auto 0; width: auto; height: auto;
    flex-direction: row; align-items: center; justify-content: space-between;
    gap: 1.5rem; padding: 0.85rem 1.5rem;
    border-right: 0; border-bottom: 1px solid var(--line);
  }
  .rail nav { flex-direction: row; flex-wrap: wrap; gap: 1.25rem; }
  .rail nav a { grid-template-columns: none; border: 0 !important; padding: 0; font-size: 0.82rem; }
  .rail nav a i { display: none; }
  .rail .rail-foot { display: none; }
  .page { margin-left: 0; }
  .hero-body { grid-template-columns: 1fr 260px; gap: 2.25rem; }
  .band-grid, .contact .wrap { grid-template-columns: 1fr; gap: 1.75rem; }
  .policy-grid { grid-template-columns: 300px 1fr; gap: 2.25rem; }
}
@media (max-width: 820px) {
  .wrap { padding: 0 1.6rem; }
  .hero-body { grid-template-columns: 1fr; gap: 2.5rem; }
  .shot { max-width: 300px; margin-left: 16px; }
  .spec, .datasheet { grid-template-columns: 1fr 1fr; }
  .spec div, .spec div + div { padding: 1rem 1.2rem 1.1rem 0; border-left: 0; }
  .spec div:nth-child(n+3) { border-top: 1px solid var(--line); }
  .datasheet > div + div { border-left: 0; }
  .datasheet > div:nth-child(2) { border-left: 1px solid var(--line); }
  .datasheet > div:nth-child(n+3) { border-top: 1px solid var(--line); }
  .datasheet > div:nth-child(4) { border-left: 1px solid var(--line); }
  .rows .r { grid-template-columns: 3rem 1fr; gap: 0.5rem 1.1rem; }
  .rows h3 { grid-column: 2; }
  .rows p { grid-column: 2; }
  .rows .n { grid-row: span 2; }
  .policy-grid { grid-template-columns: 1fr; }
  .plate { max-width: 460px; }
}
@media (max-width: 560px) {
  .rail { flex-direction: column; align-items: flex-start; gap: 0.7rem; }
  .rail nav { gap: 0.9rem; }
  .rail nav a { font-size: 0.78rem; }
  .sec, .band, .contact { padding: 3.2rem 0; }
  .hero .wrap { padding-top: 2.75rem; }
  .spec, .datasheet { grid-template-columns: 1fr; }
  .spec div, .spec div + div { border-left: 0; }
  .spec div + div { border-top: 1px solid var(--line); }
  .datasheet > div + div { border-left: 0 !important; border-top: 1px solid var(--line); }
}