/* VKBDevCfg Explained — cockpit theme.
   Black glass, amber phosphor, one cold-blue secondary. No images, no build step. */

@import url("https://fonts.googleapis.com/css2?family=Michroma&family=Sintony:wght@400;700&family=Share+Tech+Mono&display=swap");

:root {
  --bg: #050403;
  --bg-2: #0d0a06;
  --bg-3: #171008;
  --line: #3a2408;
  --line-2: #6b3d08;
  --fg: #f3dcc0;
  --fg-dim: #c39a6b;
  --fg-faint: #8a6a45;
  --accent: #ff7100;          /* HUD amber */
  --accent-hot: #ffae3b;
  --accent-2: #2fb4ff;        /* secondary: scanner blue */
  --ok: #5ed16a;
  --warn: #ffc400;
  --bad: #ff3b30;
  --glow: 0 0 12px rgba(255, 113, 0, .45);
  --mono: "Share Tech Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --sans: "Sintony", "Segoe UI", system-ui, -apple-system, Roboto, sans-serif;
  --caps: "Michroma", "Eurostile", "Bank Gothic", "Segoe UI", system-ui, sans-serif;
  --maxw: 1240px;
  --cut: 14px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 76px; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background:
    radial-gradient(1200px 500px at 50% -200px, rgba(255, 113, 0, .10), transparent 70%),
    repeating-linear-gradient(0deg, rgba(255, 140, 40, .022) 0 1px, transparent 1px 3px),
    var(--bg);
  background-attachment: fixed;
  color: var(--fg);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent-hot); text-decoration: none; border-bottom: 1px solid rgba(255, 174, 59, .35); }
a:hover { color: #000; background: var(--accent); border-bottom-color: var(--accent); }

::selection { background: var(--accent); color: #000; }

/* ---------- top bar: topbar.css, shared with the config tool ---------- */

/* ---------- layout ---------- */

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

.layout { display: grid; grid-template-columns: 236px minmax(0, 1fr); gap: 44px; }

.sidebar {
  position: sticky; top: 55px; align-self: start;
  height: calc(100vh - 55px); overflow-y: auto;
  padding: 26px 14px 40px 0;
  border-right: 1px solid var(--line);
  scrollbar-width: thin; scrollbar-color: var(--line-2) transparent;
}
.sidebar .brand {
  font-family: var(--caps); font-size: 11.5px; letter-spacing: .14em; text-transform: uppercase;
  margin-bottom: 4px; display: block; color: var(--accent); border: none;
}
.sidebar .brand:hover { background: none; color: var(--accent-hot); }
.sidebar .sub { color: var(--fg-faint); font-size: 12px; margin-bottom: 20px; }

.nav-group { margin-bottom: 18px; }
.group-title {
  font-family: var(--caps); font-size: 9.5px; letter-spacing: .18em; text-transform: uppercase;
  color: var(--fg-faint); margin: 0 0 6px 10px;
}
.sidebar a.item {
  display: block; padding: 5px 10px; border: none; border-left: 2px solid transparent;
  color: var(--fg-dim); font-size: 13.5px; line-height: 1.4;
}
.sidebar a.item:hover { background: var(--accent); color: #000; }
.sidebar a.item.active { border-left-color: var(--accent); color: var(--accent); background: var(--bg-3); }
.sidebar a.item.active:hover { color: #000; background: var(--accent); }

@media (max-width: 900px) {
  .layout { grid-template-columns: 1fr; gap: 0; }
  .sidebar { position: static; height: auto; border-right: none;
             border-bottom: 1px solid var(--line); padding: 16px 0; margin-bottom: 24px; }
  .sidebar .group-title, .sidebar .sub { display: none; }
  .nav-group { display: inline; margin: 0; }
  .sidebar a.item { display: inline-block; }
}

/* ---------- hero ---------- */

.hero {
  position: relative; overflow: hidden;
  border-bottom: 1px solid var(--line-2);
  padding: 70px 0 52px; margin-bottom: 40px;
  background:
    linear-gradient(180deg, rgba(255, 113, 0, .09), transparent 60%),
    repeating-linear-gradient(90deg, rgba(255, 113, 0, .05) 0 1px, transparent 1px 80px),
    repeating-linear-gradient(0deg, rgba(255, 113, 0, .05) 0 1px, transparent 1px 80px);
}
.hero::after {            /* horizon arc */
  content: ""; position: absolute; left: 50%; bottom: -1180px; width: 2400px; height: 1240px;
  transform: translateX(-50%); border-radius: 50%;
  border: 1px solid rgba(255, 113, 0, .55);
  box-shadow: 0 0 60px rgba(255, 113, 0, .25), inset 0 0 80px rgba(255, 113, 0, .12);
  pointer-events: none;
}
.hero .wrap { position: relative; z-index: 1; }
.hero .eyebrow {
  font-family: var(--caps); font-size: 10.5px; letter-spacing: .3em; text-transform: uppercase;
  color: var(--accent-2); margin: 0 0 14px;
}
.hero h1 {
  margin: 0 0 16px; font-family: var(--caps); font-weight: 400;
  font-size: clamp(26px, 4.6vw, 50px); line-height: 1.12; letter-spacing: .06em;
  text-transform: uppercase; color: var(--accent); text-shadow: var(--glow);
}
.hero h1 .thin { color: var(--fg); text-shadow: none; }
.hero p.lede { font-size: 18px; color: var(--fg); max-width: 70ch; margin: 0 0 24px; }
.credit {
  font-size: 13.5px; color: var(--fg-dim);
  background: rgba(13, 10, 6, .85); border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  padding: 12px 16px; max-width: 92ch;
}
.credit strong { color: var(--fg); }

/* stat readouts */
.readouts { display: grid; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); gap: 12px; margin: 28px 0 0; }
.readout {
  border: 1px solid var(--line-2); background: rgba(13, 10, 6, .88); padding: 14px 16px 12px;
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, 0 100%);
}
.readout .v { font-family: var(--caps); font-size: 24px; color: var(--accent); text-shadow: var(--glow); line-height: 1.2; }
.readout .k { font-family: var(--caps); font-size: 9.5px; letter-spacing: .16em; text-transform: uppercase; color: var(--fg-dim); margin-top: 6px; }

/* ---------- typography ---------- */

h2 {
  font-family: var(--caps); font-weight: 400; text-transform: uppercase;
  font-size: 19px; letter-spacing: .12em; line-height: 1.35;
  color: var(--accent); margin: 64px 0 14px; padding: 0 0 10px;
  border-bottom: 1px solid var(--line-2);
  background: linear-gradient(90deg, var(--accent) 0 64px, transparent 64px) bottom left / 100% 3px no-repeat;
  scroll-margin-top: 76px;
}
h2 .anchor { color: var(--fg-faint); border: none; margin-right: 10px; font-size: .8em; }
h2 .anchor:hover { background: none; color: var(--accent-hot); }
h2 .num { color: var(--accent-2); margin-right: 14px; }
h3 {
  font-family: var(--caps); font-weight: 400; text-transform: uppercase;
  font-size: 13px; letter-spacing: .12em; color: var(--fg); margin: 34px 0 10px;
}
h3::before { content: ""; display: inline-block; width: 7px; height: 11px; background: var(--accent); margin-right: 10px; transform: skewX(-18deg); }
h4 { font-size: 15px; margin: 22px 0 6px; font-weight: 700; color: var(--accent-hot); }
p { margin: 0 0 14px; max-width: 78ch; }
ul, ol { max-width: 78ch; padding-left: 22px; margin: 0 0 14px; }
li { margin-bottom: 6px; }
li::marker { color: var(--accent); }
strong { color: #fff3e2; }
code, kbd, pre { font-family: var(--mono); }
code {
  font-size: .93em; background: var(--bg-3); border: 1px solid var(--line);
  padding: 1px 5px; color: var(--accent-hot);
}
pre {
  background: #000; border: 1px solid var(--line-2); border-left: 3px solid var(--accent);
  padding: 14px 16px; overflow-x: auto; font-size: 13.5px; line-height: 1.55; color: var(--fg-dim);
}
pre code { background: none; border: none; padding: 0; color: inherit; font-size: inherit; }
pre .c { color: var(--fg-faint); }
pre .hi { color: var(--accent-hot); }
pre .b { color: var(--accent-2); }

hr { border: none; border-top: 1px solid var(--line); margin: 44px 0; }

blockquote {
  margin: 16px 0; padding: 12px 18px;
  border-left: 3px solid var(--accent-2); background: rgba(47, 180, 255, .06);
  color: var(--fg-dim); font-size: 14.5px; line-height: 1.6;
}
blockquote > :last-child { margin-bottom: 0; }

/* ---------- components ---------- */

.card, .tile, .chain .node {
  background: var(--bg-2); border: 1px solid var(--line-2);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
}
.card { padding: 18px 22px; margin: 18px 0; }
.card > :last-child { margin-bottom: 0; }

.note {
  border: 1px solid var(--line); border-left: 3px solid var(--line-2); background: var(--bg-2);
  padding: 13px 16px; margin: 16px 0; font-size: 14.5px;
}
.note > :last-child { margin-bottom: 0; }
.note .tag {
  display: block; font-family: var(--caps); font-size: 9.5px; letter-spacing: .18em;
  text-transform: uppercase; margin-bottom: 7px; color: var(--fg-dim);
}
.note.tip { border-left-color: var(--ok); }            .note.tip .tag { color: var(--ok); }
.note.gotcha { border-left-color: var(--warn); }       .note.gotcha .tag { color: var(--warn); }
.note.warn { border-left-color: var(--bad); background: rgba(255, 59, 48, .07); }
.note.warn .tag { color: var(--bad); }
.note.info { border-left-color: var(--accent-2); }     .note.info .tag { color: var(--accent-2); }

.tablewrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; margin: 16px 0 20px; font-size: 14px; }
th, td { text-align: left; padding: 9px 12px; border-bottom: 1px solid var(--line); vertical-align: top; }
th {
  font-family: var(--caps); font-weight: 400; font-size: 9.5px; text-transform: uppercase;
  letter-spacing: .14em; color: var(--accent); border-bottom: 1px solid var(--accent);
  background: rgba(255, 113, 0, .07);
}
tbody tr:hover { background: rgba(255, 113, 0, .08); }
td code { white-space: nowrap; }
td.ok { color: var(--ok); } td.bad { color: var(--bad); } td.dim { color: var(--fg-faint); }

.grid { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); margin: 16px 0 20px; }
.grid.two { grid-template-columns: repeat(auto-fit, minmax(310px, 1fr)); }
.tile { padding: 16px 18px; }
.tile h4 { margin-top: 0; font-family: var(--caps); font-weight: 400; font-size: 11.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }
.tile p { font-size: 14px; color: var(--fg-dim); margin-bottom: 0; }
.tile p + p { margin-top: 8px; }
a.tile { display: block; border-bottom: 1px solid var(--line-2); color: inherit; }
a.tile:hover { background: var(--accent); }
a.tile:hover h4, a.tile:hover p { color: #000; }

.chain { display: flex; flex-wrap: wrap; gap: 10px; align-items: stretch; margin: 20px 0 10px; }
.chain .node { flex: 1 1 180px; padding: 14px 16px; }
.chain .node .lbl { font-family: var(--caps); font-size: 9.5px; letter-spacing: .16em; text-transform: uppercase; color: var(--accent-2); margin-bottom: 6px; }
.chain .node h4 { margin: 0 0 6px; font-size: 15px; color: var(--accent); }
.chain .node p { font-size: 13px; color: var(--fg-dim); margin: 0; }
.chain .arrow { align-self: center; color: var(--accent); font-size: 20px; flex: 0 0 auto; }
@media (max-width: 760px) { .chain .arrow { display: none; } }

/* tabs */
.tabs { display: flex; flex-wrap: wrap; gap: 2px; margin: 18px 0 0; border-bottom: 1px solid var(--accent); }
.tabs button {
  background: var(--bg-2); border: 1px solid var(--line); border-bottom: none;
  color: var(--fg-dim); font-family: var(--caps); font-size: 10px; letter-spacing: .12em;
  text-transform: uppercase; padding: 9px 13px; cursor: pointer;
}
.tabs button:hover { color: #000; background: var(--accent-hot); }
.tabs button.on { color: #000; background: var(--accent); border-color: var(--accent); }
.tabpanel { padding: 18px 2px 4px; }
.tabpanel[hidden] { display: none; }

/* search */
.searchwrap { position: relative; margin: 0 0 26px; }
.searchwrap input {
  width: 100%; background: #000; border: 1px solid var(--line-2);
  color: var(--accent-hot); font-family: var(--mono); font-size: 14px;
  padding: 10px 12px 10px 36px; border-radius: 0;
}
.searchwrap input::placeholder { color: var(--fg-faint); }
.searchwrap input:focus { outline: none; border-color: var(--accent); box-shadow: var(--glow); }
.searchwrap::before { content: ">_"; position: absolute; left: 11px; top: 50%; transform: translateY(-52%); color: var(--accent); font-family: var(--mono); font-size: 13px; }
.hidden-by-search { display: none !important; }
mark { background: var(--accent); color: #000; padding: 0 2px; }

.recipe { counter-reset: r; }
.recipe > h3 { counter-increment: r; }
.recipe > h3::before { content: counter(r, decimal-leading-zero) " // "; color: var(--accent); display: inline; width: auto; height: auto; background: none; transform: none; margin: 0; }

/* transcript */
.ts-line { display: grid; grid-template-columns: 62px 1fr; gap: 12px; padding: 3px 6px; font-size: 14.2px; }
.ts-line .t { color: var(--accent-2); font-family: var(--mono); font-size: 12.5px; padding-top: 2px; cursor: pointer; }
.ts-line .t:hover { color: var(--accent); }
.ts-line.cue { background: rgba(255, 113, 0, .04); }
.ts-body { max-height: 460px; overflow-y: auto; padding-right: 10px; border: 1px solid var(--line); background: #000; }
.ts-body h3 { margin: 22px 6px 8px; color: var(--accent); }

.btn {
  background: transparent; border: 1px solid var(--accent); color: var(--accent);
  font-family: var(--caps); font-size: 10.5px; letter-spacing: .14em; text-transform: uppercase;
  padding: 9px 16px; cursor: pointer; display: inline-block;
}
.btn:hover { background: var(--accent); color: #000; }
.btn.primary { background: var(--accent); color: #000; }
.btn.primary:hover { background: var(--accent-hot); }
.cta { display: flex; align-items: center; gap: 12px 22px; flex-wrap: wrap; max-width: none; margin: 28px 0 30px; color: var(--fg-dim); font-size: 15px; }
.cta .btn { font-size: 12px; padding: 13px 22px; white-space: nowrap; }
.cta span { flex: 1 1 30ch; max-width: 46ch; }

kbd, kbd.key {
  background: #000; border: 1px solid var(--accent); padding: 1px 7px;
  font-size: 12.5px; color: var(--accent); white-space: nowrap; text-transform: uppercase;
}

.pill {
  display: inline-block; font-family: var(--caps); font-size: 9px; letter-spacing: .12em;
  padding: 3px 8px; text-transform: uppercase; white-space: nowrap;
  background: var(--bg-3); color: var(--fg-dim); border: 1px solid var(--line-2);
}
.pill.on, .pill.verified { color: #000; background: var(--ok); border-color: var(--ok); }
.pill.static { color: var(--accent-2); border-color: var(--accent-2); background: transparent; }
.pill.off { color: var(--fg-faint); }
.pill.danger { color: #000; background: var(--bad); border-color: var(--bad); }
.pill.caution { color: #000; background: var(--warn); border-color: var(--warn); }

/* ---------- writeup-specific ---------- */

/* frame diagram: byte boxes */
.frame { display: flex; flex-wrap: wrap; gap: 3px; margin: 16px 0 6px; font-family: var(--mono); }
.frame .f { flex: var(--w, 1) 1 0; min-width: 62px; border: 1px solid var(--line-2); background: var(--bg-2); padding: 8px 8px 7px; text-align: center; }
.frame .f b { display: block; color: var(--accent-hot); font-weight: 400; font-size: 15px; }
.frame .f span { display: block; font-family: var(--caps); font-size: 8.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--fg-dim); margin-top: 4px; }
.frame .f.hot { border-color: var(--accent); background: rgba(255, 113, 0, .12); }
.frame .f.cold { border-color: var(--accent-2); }
.frame .f.cold b { color: var(--accent-2); }
.cap { font-size: 12.5px; color: var(--fg-faint); margin: 0 0 18px; }

/* sequence log */
.seq { border: 1px solid var(--line-2); background: #000; margin: 16px 0 20px; font-family: var(--mono); font-size: 13.5px; }
.seq .row { display: grid; grid-template-columns: 92px 1fr; border-bottom: 1px solid var(--line); }
.seq .row:last-child { border-bottom: none; }
.seq .who { padding: 8px 10px; font-family: var(--caps); font-size: 9px; letter-spacing: .14em; text-transform: uppercase; border-right: 1px solid var(--line); }
.seq .what { padding: 7px 12px; color: var(--fg-dim); }
.seq .what em { font-style: normal; color: var(--fg-faint); }
.seq .tx .who { color: var(--accent); } .seq .tx .what b { color: var(--accent-hot); font-weight: 400; }
.seq .rx .who { color: var(--accent-2); } .seq .rx .what b { color: var(--accent-2); font-weight: 400; }
.seq .ev .who { color: var(--fg-faint); } .seq .ev .what { color: var(--fg-faint); font-family: var(--sans); font-size: 13px; }

/* system diagram (inline SVG) */
.diagram { border: 1px solid var(--line-2); background: #000; padding: 14px 12px 8px; margin: 18px 0 20px; overflow-x: auto; }
.diagram svg { display: block; width: 100%; min-width: 760px; height: auto; }
.diagram .box-out { fill: rgba(255, 113, 0, .03); stroke: var(--line-2); stroke-dasharray: 4 4; }
.diagram .box { fill: var(--bg-2); stroke: var(--fg-faint); }
.diagram .box-a { fill: rgba(255, 113, 0, .10); stroke: var(--accent); stroke-width: 1.5; }
.diagram .box-b { fill: rgba(47, 180, 255, .10); stroke: var(--accent-2); stroke-width: 1.5; }
.diagram text { font-family: var(--sans); }
.diagram .t { fill: var(--fg); font-size: 13.5px; font-weight: 700; }
.diagram .s { fill: var(--fg-dim); font-size: 12.5px; }
.diagram .s-a { fill: var(--accent-hot); font-size: 12.5px; }
.diagram .s-b { fill: var(--accent-2); font-size: 12.5px; }
.diagram .cap-a, .diagram .cap-b, .diagram .cap-d { font-family: var(--caps); font-size: 11px; letter-spacing: .14em; }
.diagram .cap-a { fill: var(--accent); } .diagram .cap-b { fill: var(--accent-2); } .diagram .cap-d { fill: var(--fg-faint); font-size: 9.5px; }
.diagram .ln-a { stroke: var(--accent); stroke-width: 3; fill: none; }
.diagram .ln-b { stroke: var(--accent-2); stroke-width: 3; fill: none; }
.diagram .ln-d { stroke: var(--fg-faint); stroke-width: 1.5; fill: none; }
.diagram .fa { fill: var(--accent); } .diagram .fb { fill: var(--accent-2); } .diagram .fd { fill: var(--fg-faint); }

/* packet-style layout diagrams */
.pkt { margin: 18px 0 8px; border: 1px solid var(--line-2); background: #000; padding: 0 4px 4px; overflow-x: auto; }
.pkt .ptitle { font-family: var(--caps); font-size: 10.5px; letter-spacing: .14em; text-transform: uppercase; color: var(--accent); padding: 9px 8px 8px; }
.pkt .ptitle em { font-style: normal; color: var(--fg-faint); margin-left: 12px; letter-spacing: .1em; }
.prow { display: flex; gap: 3px; margin-top: 3px; min-width: 620px; }
.prow .off { flex: 0 0 74px; font-family: var(--mono); font-size: 12.5px; color: var(--accent-2); align-self: center; padding-left: 6px; }
.pc { flex: var(--w) 1 0; min-width: 0; padding: 9px 4px 7px; text-align: center; color: #0b0704; background: var(--c); overflow: hidden; }
.pc b { display: block; font-family: var(--sans); font-weight: 700; font-size: 13px; line-height: 1.25; }
.pc span { display: block; font-family: var(--mono); font-size: 11.5px; opacity: .75; margin-top: 2px; }
.prow.bits .pc { padding: 8px 1px 6px; }
.prow.bits .pc b { font-size: 12px; white-space: nowrap; }
.pc.hdr { --c: #ffd9a8; } .pc.glb { --c: #c9641a; } .pc.axs { --c: var(--accent); } .pc.bt { --c: var(--accent-2); }
.pc.ext { --c: #a584ff; } .pc.led { --c: var(--ok); } .pc.det { --c: var(--warn); } .pc.bad { --c: #ff6a5e; }
.pc.unk, .pc.dim { background: repeating-linear-gradient(45deg, #3a2408 0 5px, #1d1309 5px 10px); color: var(--fg-dim); }
.pc.dim { background: repeating-linear-gradient(45deg, #0f4a6e 0 5px, #0a3048 5px 10px); color: #bfe6ff; }
.pc.zero { background: #171008; color: var(--fg-faint); }
.pc.ver { outline: 2px solid #fff; outline-offset: -2px; box-shadow: inset 0 0 0 4px #000; }
.legend { display: flex; flex-wrap: wrap; gap: 6px 16px; font-size: 12.5px; color: var(--fg-dim); margin: 8px 0 18px; }
.legend span::before { content: ""; display: inline-block; width: 11px; height: 11px; margin-right: 6px; vertical-align: -1px; background: var(--c); border: 1px solid rgba(255,255,255,.15); }
.legend .lg-ver::before { background: #000; border: 2px solid #fff; }

/* retraction list */
.retract { border-left: 3px solid var(--bad); padding: 2px 0 2px 18px; margin: 22px 0; }
.retract .was { color: var(--fg-faint); text-decoration: line-through; text-decoration-color: var(--bad); margin-bottom: 4px; max-width: 78ch; }
.retract .is { margin: 0; }
.retract .is::before { content: "CORRECTION — "; font-family: var(--caps); font-size: 9.5px; letter-spacing: .14em; color: var(--ok); }

.bignum { font-family: var(--caps); color: var(--accent); text-shadow: var(--glow); }

footer {
  border-top: 1px solid var(--line-2); margin-top: 80px; padding: 26px 0 60px;
  color: var(--fg-faint); font-size: 13px;
}
footer p { max-width: 92ch; }