/* ============================================================
   SETURA — Telecom & Utility Network Design
   Visual language: engineering drawing. Route lines, splice
   nodes, drafting grid, mono annotations, titleblock footer.
   ============================================================ */

:root {
  --ink:        #0F2438;   /* deep navy — drawing ink */
  --ink-soft:   #3A4C5E;
  --teal:       #2E7D8A;   /* brand accent — the route */
  --teal-deep:  #1F5C66;
  --paper:      #F7F8F6;   /* drafting paper */
  --paper-2:    #EDF1F1;
  --grid:       #DCE3E4;
  --rule:       #C6D0D2;
  --white:      #FFFFFF;

  --f-display: 'Archivo', system-ui, sans-serif;
  --f-body:    'IBM Plex Sans', system-ui, sans-serif;
  --f-mono:    'IBM Plex Mono', ui-monospace, monospace;

  --wrap: 1120px;
  --gut: 2rem;
}

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--f-body);
  font-size: 17px;
  line-height: 1.65;
  color: var(--ink-soft);
  background-color: var(--paper);
  /* drafting grid */
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 56px 56px;
  background-position: -1px -1px;
  -webkit-font-smoothing: antialiased;
}

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

/* ---------- Type ---------- */
h1, h2, h3 {
  font-family: var(--f-display);
  color: var(--ink);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.12;
  margin: 0;
}
h1 { font-size: clamp(2.4rem, 5.5vw, 4.1rem); }
h2 { font-size: clamp(1.7rem, 3.2vw, 2.4rem); }
h3 { font-size: 1.15rem; letter-spacing: -0.01em; }
p { margin: 0 0 1rem; }
a { color: var(--teal-deep); }

/* mono annotation — the drawing callout */
.anno {
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--teal);
  display: block;
  margin-bottom: 0.9rem;
}
.anno::before { content: "— "; color: var(--rule); }

.lede { font-size: 1.2rem; color: var(--ink-soft); max-width: 62ch; }

/* ---------- Header ---------- */
header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(247,248,246,0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--rule);
}
.bar {
  max-width: var(--wrap); margin: 0 auto; padding: 0.9rem var(--gut);
  display: flex; align-items: center; justify-content: space-between; gap: 1rem;
}
.brand {
  font-family: var(--f-display); font-weight: 700;
  font-size: 1.35rem; letter-spacing: 0.22em;
  color: var(--ink); text-decoration: none;
}
.brand span { color: var(--teal); }
nav ul { display: flex; gap: 1.6rem; list-style: none; margin: 0; padding: 0; }
nav a {
  font-family: var(--f-mono); font-size: 0.76rem; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--ink-soft); text-decoration: none;
  padding-bottom: 3px; border-bottom: 2px solid transparent;
}
nav a:hover, nav a[aria-current="page"] { color: var(--ink); border-bottom-color: var(--teal); }

/* ---------- Hero ---------- */
.hero { padding: 5.5rem 0 4rem; position: relative; }
.hero h1 { max-width: 17ch; }
.hero h1 em { font-style: normal; color: var(--teal); }
.hero .lede { margin-top: 1.5rem; }

/* the route drawing */
.route { width: 100%; height: auto; margin-top: 3rem; display: block; }
.route .path {
  fill: none; stroke: var(--teal); stroke-width: 2;
  stroke-dasharray: 1200; stroke-dashoffset: 1200;
  animation: draw 2.4s cubic-bezier(.65,.05,.36,1) forwards;
}
.route .node { fill: var(--paper); stroke: var(--teal); stroke-width: 2; opacity: 0; animation: pop .45s ease forwards; }
.route .node.n1 { animation-delay: .55s; }
.route .node.n2 { animation-delay: 1.15s; }
.route .node.n3 { animation-delay: 1.75s; }
.route .node.n4 { animation-delay: 2.3s; }
.route .lbl {
  font-family: var(--f-mono); font-size: 10px; letter-spacing: .12em;
  fill: var(--ink-soft); text-transform: uppercase; opacity: 0;
  animation: fade .5s ease forwards;
}
.route .lbl.n1 { animation-delay: .75s; }
.route .lbl.n2 { animation-delay: 1.35s; }
.route .lbl.n3 { animation-delay: 1.95s; }
.route .lbl.n4 { animation-delay: 2.5s; }
.route .base { stroke: var(--rule); stroke-width: 1; stroke-dasharray: 4 4; fill: none; }

@keyframes draw { to { stroke-dashoffset: 0; } }
@keyframes pop  { to { opacity: 1; } }
@keyframes fade { to { opacity: 1; } }

@media (prefers-reduced-motion: reduce) {
  .route .path { animation: none; stroke-dashoffset: 0; }
  .route .node, .route .lbl { animation: none; opacity: 1; }
  html { scroll-behavior: auto; }
}

/* ---------- Sections ---------- */
section { padding: 4.5rem 0; }
.band { background: var(--white); border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule); }
.band-ink {
  background: var(--ink);
  border: 0;
}
.band-ink h2, .band-ink h3 { color: var(--white); }
.band-ink p { color: #A9BCCB; }
.band-ink .anno { color: #6FB3BE; }

/* ---------- Route-marked list (the signature, reused) ---------- */
.lines { list-style: none; margin: 0; padding: 0; position: relative; }
.lines::before {
  content: ""; position: absolute; left: 7px; top: 12px; bottom: 12px;
  width: 2px; background: var(--rule);
}
.lines > li {
  position: relative; padding: 0 0 2.4rem 3rem;
}
.lines > li::before {
  content: ""; position: absolute; left: 0; top: 9px;
  width: 16px; height: 16px; background: var(--paper);
  border: 2px solid var(--teal); border-radius: 2px;
  transform: rotate(45deg);
}
.band .lines > li::before { background: var(--white); }
.lines > li:last-child { padding-bottom: 0; }
.lines .ref {
  font-family: var(--f-mono); font-size: 0.7rem; letter-spacing: .14em;
  color: var(--teal); display: block; margin-bottom: .35rem;
}
.lines h3 { margin-bottom: .4rem; }
.lines p { margin: 0; font-size: 0.98rem; }

/* ---------- Cards / grids ---------- */
.grid { display: grid; gap: 1px; background: var(--rule); border: 1px solid var(--rule); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.cell { background: var(--white); padding: 1.7rem 1.5rem; }
.cell .k {
  font-family: var(--f-display); font-size: 1.6rem; font-weight: 700;
  color: var(--teal); display: block; line-height: 1;
}
.cell .v {
  font-family: var(--f-mono); font-size: .68rem; letter-spacing: .14em;
  text-transform: uppercase; color: var(--ink); display: block; margin: .6rem 0 .4rem;
}
.cell .d { font-size: .88rem; color: var(--ink-soft); margin: 0; }

.spec { margin: 0; }
.spec dt {
  font-family: var(--f-mono); font-size: .7rem; letter-spacing: .14em;
  text-transform: uppercase; color: var(--teal); margin-bottom: .4rem;
}
.spec dd { margin: 0 0 1.5rem; font-size: .95rem; }

/* deliverables strip */
.deliv {
  background: var(--paper-2); border-left: 3px solid var(--teal);
  padding: 1.2rem 1.4rem; font-size: .92rem; margin-top: 1.4rem;
}
.deliv strong {
  font-family: var(--f-mono); font-size: .68rem; letter-spacing: .14em;
  text-transform: uppercase; color: var(--teal-deep); display: block; margin-bottom: .4rem;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-block; font-family: var(--f-mono); font-size: .78rem;
  letter-spacing: .12em; text-transform: uppercase; text-decoration: none;
  padding: .95rem 1.7rem; border: 2px solid var(--ink); color: var(--ink);
  background: transparent; transition: background .18s, color .18s;
}
.btn:hover { background: var(--ink); color: var(--paper); }
.btn-t { border-color: var(--teal); color: var(--teal); }
.btn-t:hover { background: var(--teal); color: var(--white); }
.btn-w { border-color: var(--white); color: var(--white); }
.btn-w:hover { background: var(--white); color: var(--ink); }
.btns { display: flex; gap: 1rem; flex-wrap: wrap; margin-top: 2rem; }

/* ---------- Titleblock footer (engineering drawing convention) ---------- */
footer { background: var(--ink); color: #A9BCCB; }
.tb {
  max-width: var(--wrap); margin: 0 auto; padding: 0 var(--gut);
  display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 1px;
}
.tb > div { padding: 2rem 1.6rem 2rem 0; }
.tb > div + div { border-left: 1px solid #26394C; padding-left: 1.6rem; }
.tb .lab {
  font-family: var(--f-mono); font-size: .66rem; letter-spacing: .16em;
  text-transform: uppercase; color: #6FB3BE; display: block; margin-bottom: .7rem;
}
.tb a { color: var(--white); text-decoration: none; border-bottom: 1px solid #3A5670; }
.tb a:hover { border-bottom-color: var(--teal); }
.tb .big { font-family: var(--f-display); font-weight: 700; font-size: 1.3rem; color: var(--white); letter-spacing: .2em; }
.tb p { margin: 0 0 .4rem; font-size: .92rem; }
.legal {
  border-top: 1px solid #26394C; margin-top: 0;
}
.legal .wrap {
  padding-top: 1.2rem; padding-bottom: 1.2rem;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: .8rem;
  font-family: var(--f-mono); font-size: .68rem; letter-spacing: .1em;
  text-transform: uppercase; color: #5E748A;
}

/* ---------- Contact ---------- */
.contact-grid { display: grid; grid-template-columns: 1.1fr 1fr; gap: 4rem; align-items: start; }

/* ---------- Focus ---------- */
a:focus-visible, .btn:focus-visible {
  outline: 3px solid var(--teal); outline-offset: 3px;
}

/* ---------- Responsive ---------- */
@media (max-width: 880px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; gap: 2.5rem; }
  .tb { grid-template-columns: 1fr; }
  .tb > div + div { border-left: 0; border-top: 1px solid #26394C; padding-left: 0; }
  .tb > div { padding: 1.6rem 0; }
}
@media (max-width: 620px) {
  :root { --gut: 1.25rem; }
  body { background-size: 40px 40px; }
  .grid-3, .grid-4 { grid-template-columns: 1fr; }
  nav ul { gap: 1rem; }
  nav a { font-size: .68rem; letter-spacing: .08em; }
  .bar { flex-direction: column; align-items: flex-start; gap: .7rem; }
  section { padding: 3.2rem 0; }
  .hero { padding: 3.5rem 0 2.5rem; }
}