:root {
  --void: #0e1218;
  --void-2: #151b24;
  --cyan: #00b4d8;
  --cyan-2: #7ee8ff;
  --earth: #3a2a1c;
  --alert: #e23a4a;
  --mute: #8aa0b0;
  --paper: #d7e6ef;
  --line: rgba(0, 180, 216, 0.28);
  --display: "Rajdhani", "Noto Sans SC", sans-serif;
  --sans: "Noto Sans SC", "PingFang SC", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, Menlo, monospace;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
section[id] { scroll-margin-top: 84px; }
body {
  margin: 0;
  color: var(--paper);
  background: var(--void);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.7;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
.app-link { color: var(--cyan); text-decoration: underline; text-underline-offset: 3px; }
button { font-family: inherit; cursor: pointer; }
code {
  font-family: var(--mono);
  color: var(--cyan);
  background: rgba(0, 180, 216, 0.12);
  padding: 0.05em 0.35em;
}

.clad {
  pointer-events: none;
  position: fixed;
  inset: 0;
  z-index: 18;
  opacity: 0.14;
  background-image: url("images/texture.webp");
  background-size: 420px auto;
  mix-blend-mode: screen;
}
.otdr-trace {
  position: sticky;
  top: 56px;
  z-index: 35;
  display: block;
  width: 100%;
  height: 28px;
  background: rgba(14, 18, 24, 0.92);
}
.otdr-trace path {
  fill: none;
  stroke: var(--cyan);
  stroke-width: 2;
}

.skip { position: absolute; left: -999px; }
.skip:focus { left: 12px; top: 12px; z-index: 80; background: var(--cyan); color: var(--void); padding: 8px; }

.noc-bar {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 24px;
  background: rgba(14, 18, 24, 0.94);
  border-bottom: 1px solid var(--line);
}
.brand {
  font-family: var(--display);
  font-weight: 700;
  letter-spacing: 0.08em;
  font-size: 22px;
}
.brand small {
  display: block;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--mute);
  font-weight: 400;
}
.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--cyan);
  color: var(--cyan);
  padding: 6px 12px;
  font-family: var(--mono);
}
.nav-links { display: flex; gap: 14px; font-size: 14px; }
.nav-links a { color: var(--mute); }
.nav-links a.is-active,
.nav-links a:hover { color: var(--cyan); }
.nav-links .live { background: var(--cyan); color: var(--void); padding: 6px 12px; font-weight: 700; }

.cutaway {
  position: relative;
  min-height: 92vh;
  display: grid;
  align-items: center;
}
.cutaway > img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.cutaway::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, rgba(14, 18, 24, 0.92) 0%, rgba(14, 18, 24, 0.45) 55%, rgba(14, 18, 24, 0.2) 100%);
}
.cut-copy { position: relative; z-index: 1; padding: 10vh 6vw 8vh; max-width: 760px; }

.kicker {
  font-family: var(--mono);
  letter-spacing: 0.18em;
  font-size: 11px;
  color: var(--cyan);
  margin: 0 0 12px;
}
h1, h2, h3 { font-family: var(--display); font-weight: 700; line-height: 1.05; margin: 0 0 12px; letter-spacing: 0.02em; }
h1 { font-size: clamp(42px, 7vw, 84px); }
h2 { font-size: clamp(28px, 3.6vw, 44px); }
h3 { font-size: 22px; }
.lead, .quiet { max-width: 44em; color: var(--mute); }

.das {
  margin: 22px 0;
  padding: 16px 18px;
  border: 1px solid var(--line);
  background: rgba(14, 18, 24, 0.7);
  max-width: 28em;
}
.das-event { font-family: var(--display); font-size: 26px; margin: 0 0 8px; color: var(--cyan-2); }
.das-state { min-height: 3.2em; font-size: 14px; }
.das.is-ok .das-event { color: #9dcc9a; }
.das.is-bad .das-event { color: var(--alert); }

.cta { display: flex; flex-wrap: wrap; gap: 10px; }
.btn {
  display: inline-flex;
  align-items: center;
  padding: 10px 16px;
  border: 1px solid currentColor;
  font-family: var(--mono);
  font-size: 13px;
}
.btn.fill { background: var(--cyan); color: var(--void); border-color: var(--cyan); }
.btn.ghost { color: var(--paper); }

.duct { width: min(1100px, calc(100% - 40px)); margin: 0 auto; padding: 80px 0; }
.soil { background: var(--void-2); }

.need-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-top: 28px;
}
.need-2 article {
  padding: 20px;
  border-left: 3px solid var(--cyan);
  background: rgba(0, 180, 216, 0.05);
}
.need-2 ul { margin: 0; padding-left: 1.1em; }

.seg {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  align-items: center;
  padding: 28px 0;
  border-top: 1px solid var(--line);
}
.seg.flip > figure { order: -1; }
.km {
  font-family: var(--mono);
  color: var(--cyan);
  letter-spacing: 0.14em;
  font-size: 12px;
}
.seg img { width: 100%; height: 220px; object-fit: cover; }
.seg figcaption { font-family: var(--mono); font-size: 12px; color: var(--mute); margin-top: 8px; }

.mods, .roles-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin-top: 24px; }
.mods { grid-template-columns: repeat(4, 1fr); }
.mods article, .roles-3 article { padding: 16px; border: 1px solid var(--line); }
.mods p, .roles-3 p { color: var(--mute); }

.bound { list-style: none; margin: 0; padding: 0; counter-reset: k; }
.bound li {
  counter-increment: k;
  padding: 12px 0 12px 72px;
  border-bottom: 1px solid var(--line);
  position: relative;
}
.bound li::before {
  content: "dB-" counter(k, decimal-leading-zero);
  position: absolute;
  left: 0;
  font-family: var(--mono);
  color: var(--cyan);
  font-size: 12px;
}

.io { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.io div { padding: 20px; border: 1px solid var(--line); }
.io ul { margin: 0; padding-left: 1.1em; }

footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 24px 6vw 40px;
  border-top: 1px solid var(--line);
  font-size: 14px;
  color: var(--mute);
}

@media (max-width: 980px) {
  .need-2, .seg, .seg.flip, .mods, .roles-3, .io, footer { grid-template-columns: 1fr; }
  .seg.flip > figure { order: 0; }
  .nav-toggle { display: inline-flex; }
  .nav-links {
    display: none;
    position: absolute;
    top: 52px;
    right: 12px;
    left: 12px;
    flex-direction: column;
    background: var(--void-2);
    border: 1px solid var(--line);
    padding: 12px;
  }
  .nav-links.open { display: flex; }
  h1 { font-size: clamp(34px, 12vw, 52px); }
}