/* =========================================================
   Broadband US — Custom theme over Bootstrap 5
   Deep navy + signal-orange. Neo-grotesque sans + transitional serif.
   Bootstrap is the scaffolding; this file is the aesthetic.
   ========================================================= */

:root {
  /* Brand palette */
  --bb-navy-900: #0a1726;
  --bb-navy-800: #0f2236;
  --bb-navy-700: #16304a;
  --bb-navy-600: #1f4063;
  --bb-charcoal: #1a1f2b;
  --bb-ink: #0a1726;
  --bb-line: #d9dde3;
  --bb-line-strong: #b8bfca;
  --bb-paper: #ffffff;
  --bb-paper-2: #f5f3ee;       /* warm off-white for editorial sections */
  --bb-paper-3: #eef0f3;       /* cool grey for diagram panels */
  --bb-signal: #14c6d6;        /* primary accent — signal aqua */
  --bb-signal-700: #0e8c98;    /* darker variant for hover + body-text use */
  --bb-signal-100: #67e8f4;    /* light cyan tint for highlights */
  --bb-text: #1a1f2b;
  --bb-text-muted: #59616c;
  --bb-text-on-dark: #e6e9ef;
  --bb-text-on-dark-muted: #9aa6b4;

  /* Typography */
  --bb-font-sans: "Inter", "Helvetica Neue", Arial, system-ui, sans-serif;
  --bb-font-serif: "Source Serif 4", "Source Serif Pro", Georgia, "Times New Roman", serif;
  --bb-font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  /* Bootstrap overrides */
  --bs-primary: var(--bb-navy-800);
  --bs-body-font-family: var(--bb-font-sans);
  --bs-body-color: var(--bb-text);
  --bs-body-bg: var(--bb-paper);
  --bs-link-color: var(--bb-navy-800);
  --bs-link-hover-color: var(--bb-signal-700);
  --bs-border-color: var(--bb-line);
}

/* ---------- Base typography ---------- */
html { scroll-behavior: smooth; }
body {
  font-family: var(--bb-font-sans);
  color: var(--bb-text);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--bb-ink);
  letter-spacing: -0.01em;
}
h1 { font-weight: 600; line-height: 1.08; letter-spacing: -0.02em; }
h2 { font-weight: 600; line-height: 1.15; letter-spacing: -0.015em; }
.display-1, .display-2, .display-3, .display-4 { font-weight: 600; letter-spacing: -0.025em; }

.editorial { font-family: var(--bb-font-serif); font-weight: 400; letter-spacing: -0.005em; }
.editorial em { font-style: italic; }
.eyebrow {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--bb-signal);
  margin-bottom: 0.75rem;
  display: inline-block;
}
.eyebrow.eyebrow--muted { color: var(--bb-text-muted); }
.lede { font-size: 1.2rem; color: var(--bb-text-muted); line-height: 1.55; }
.text-mono { font-family: var(--bb-font-mono); }
.text-muted-bb { color: var(--bb-text-muted) !important; }

a { text-decoration: none; }
a:hover { text-decoration: underline; text-decoration-thickness: 1.5px; text-underline-offset: 3px; }

/* ---------- Navbar ---------- */
.bb-nav {
  background: var(--bb-paper);
  border-bottom: 1px solid var(--bb-line);
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
}
.bb-nav .navbar-brand { display: flex; align-items: center; gap: .65rem; font-weight: 600; color: var(--bb-ink); font-size: 1.05rem; letter-spacing: -0.01em; }
.bb-nav .navbar-brand:hover { color: var(--bb-ink); text-decoration: none; }
.bb-nav .navbar-brand .logo-mark {
  width: 28px; height: 28px;
  display: inline-flex; align-items: center; justify-content: center;
}
.bb-nav .nav-link { color: var(--bb-text); font-weight: 500; font-size: .95rem; padding: 0.5rem 0.9rem; }
.bb-nav .nav-link:hover { color: var(--bb-signal-700); }
.bb-nav .nav-link.active { color: var(--bb-ink); }
.bb-nav .dropdown-menu {
  border-radius: 0; border: 1px solid var(--bb-line); box-shadow: 0 12px 32px rgba(10,23,38,0.08);
  padding: .5rem 0; margin-top: .25rem;
}
.bb-nav .dropdown-item { padding: .55rem 1rem; font-size: .92rem; color: var(--bb-text); }
.bb-nav .dropdown-item:hover { background: var(--bb-paper-2); color: var(--bb-ink); }

/* ---------- Buttons ---------- */
.btn { border-radius: 2px; font-weight: 500; padding: 0.65rem 1.2rem; letter-spacing: 0.005em; }
.btn-primary {
  background: var(--bb-signal);
  border-color: var(--bb-signal);
  color: #fff;
}
.btn-primary:hover, .btn-primary:focus {
  background: var(--bb-signal-700);
  border-color: var(--bb-signal-700);
  color: #fff;
}
.btn-dark {
  background: var(--bb-navy-800); border-color: var(--bb-navy-800); color: #fff;
}
.btn-dark:hover { background: var(--bb-navy-900); border-color: var(--bb-navy-900); }
.btn-outline-dark {
  border-color: var(--bb-ink); color: var(--bb-ink);
}
.btn-outline-dark:hover { background: var(--bb-ink); color: #fff; }
.btn-outline-light-bb {
  border: 1px solid rgba(230,233,239,0.4); color: #fff;
}
.btn-outline-light-bb:hover { background: rgba(255,255,255,0.08); color: #fff; }
.btn-link-arrow {
  font-weight: 600; color: var(--bb-ink); padding: 0;
}
.btn-link-arrow::after { content: " →"; transition: margin-left .15s ease-out; display: inline-block; margin-left: .3rem; }
.btn-link-arrow:hover { color: var(--bb-signal-700); text-decoration: none; }
.btn-link-arrow:hover::after { margin-left: .55rem; }

/* ---------- Section scaffolding ---------- */
section { padding: 5rem 0; }
section.section-tight { padding: 3.5rem 0; }
.section-dark {
  background: var(--bb-navy-900);
  color: var(--bb-text-on-dark);
}
.section-dark h1, .section-dark h2, .section-dark h3, .section-dark h4 { color: #fff; }
.section-dark .lede { color: var(--bb-text-on-dark-muted); }
.section-dark .eyebrow { color: var(--bb-signal); }
.section-paper { background: var(--bb-paper-2); }
.section-cool   { background: var(--bb-paper-3); }
.section-divider { border-top: 1px solid var(--bb-line); }
.section-divider-strong { border-top: 1px solid var(--bb-line-strong); }
.rule-accent { width: 48px; height: 3px; background: var(--bb-signal); display: block; }

/* ---------- Hero ---------- */
.hero {
  background: var(--bb-navy-900);
  color: var(--bb-text-on-dark);
  padding: 6.5rem 0 5.5rem;
  position: relative;
  overflow: hidden;
}
.hero h1 { color: #fff; font-size: clamp(2.1rem, 4.4vw, 3.5rem); max-width: 22ch; }
.hero .lede { color: var(--bb-text-on-dark-muted); max-width: 52ch; font-size: 1.15rem; }
.hero .eyebrow { color: var(--bb-signal); }
.hero-grid {
  position: absolute; inset: 0; pointer-events: none; opacity: .18;
  background-image:
    linear-gradient(to right, rgba(255,255,255,0.06) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255,255,255,0.06) 1px, transparent 1px);
  background-size: 64px 64px;
}
.hero-stat {
  border-top: 1px solid rgba(255,255,255,0.15);
  padding-top: 1rem;
}
.hero-stat .num { font-family: var(--bb-font-serif); font-size: 2rem; color: #fff; line-height: 1; }
.hero-stat .lbl { font-size: .82rem; color: var(--bb-text-on-dark-muted); letter-spacing: 0.04em; text-transform: uppercase; }

.page-header {
  background: var(--bb-navy-900);
  color: var(--bb-text-on-dark);
  padding: 5rem 0 3.5rem;
  position: relative; overflow: hidden;
}
.page-header h1 { color: #fff; }
.page-header .lede { color: var(--bb-text-on-dark-muted); }
.page-header .eyebrow { color: var(--bb-signal); }

/* ---------- Cards ---------- */
.card-bb {
  background: #fff;
  border: 1px solid var(--bb-line);
  border-radius: 0;
  padding: 2rem;
  height: 100%;
  transition: border-color .15s ease, transform .15s ease;
  display: flex; flex-direction: column;
}
.card-bb:hover { border-color: var(--bb-ink); }
.card-bb .card-eyebrow {
  font-size: 0.72rem; font-weight: 600; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--bb-text-muted); margin-bottom: .85rem;
}
.card-bb h3 { font-size: 1.25rem; margin-bottom: .65rem; }
.card-bb p { color: var(--bb-text-muted); margin-bottom: 1.25rem; }
.card-bb .btn-link-arrow { margin-top: auto; }

.case-card {
  background: #fff;
  border: 1px solid var(--bb-line);
  padding: 0;
  display: flex; flex-direction: column;
  transition: border-color .15s ease;
  height: 100%;
}
.case-card:hover { border-color: var(--bb-ink); }
.case-card .case-card-thumb {
  aspect-ratio: 16 / 9;
  background: var(--bb-paper-3);
  border-bottom: 1px solid var(--bb-line);
  position: relative;
}
.case-card .case-card-body { padding: 1.5rem; display: flex; flex-direction: column; flex-grow: 1; }
.case-card .case-card-meta { font-size: .78rem; color: var(--bb-text-muted); letter-spacing: .08em; text-transform: uppercase; margin-bottom: .65rem; }
.case-card h3 { font-size: 1.15rem; }

/* ---------- Lists, KPI, definitions ---------- */
.kpi {
  border-top: 2px solid var(--bb-ink);
  padding-top: 1rem;
}
.kpi .num { font-family: var(--bb-font-serif); font-size: 2.4rem; line-height: 1; color: var(--bb-ink); }
.kpi .lbl { font-size: .82rem; color: var(--bb-text-muted); letter-spacing: 0.04em; text-transform: uppercase; margin-top: .35rem; }

.def-list { list-style: none; padding: 0; margin: 0; }
.def-list li {
  display: grid; grid-template-columns: 9.5rem 1fr; gap: 1.25rem;
  padding: 0.85rem 0; border-top: 1px solid var(--bb-line);
}
.def-list li:last-child { border-bottom: 1px solid var(--bb-line); }
.def-list dt, .def-list .dt {
  font-size: .8rem; letter-spacing: .08em; text-transform: uppercase; color: var(--bb-text-muted);
  font-weight: 600;
}
.def-list dd, .def-list .dd { margin: 0; color: var(--bb-text); }

.checklist { list-style: none; padding: 0; margin: 0; }
.checklist li {
  padding-left: 1.5rem; position: relative; margin-bottom: 0.5rem;
}
.checklist li::before {
  content: ""; width: 8px; height: 8px; background: var(--bb-signal);
  position: absolute; left: 0; top: 0.55rem;
}

/* ---------- Diagrams (engineered, not infographic) ---------- */
.diagram-panel {
  background: var(--bb-paper-3);
  border: 1px solid var(--bb-line);
  padding: 2rem;
  position: relative;
  font-family: var(--bb-font-mono);
  font-size: 0.78rem;
  color: var(--bb-text-muted);
}
.diagram-panel svg { display: block; width: 100%; height: auto; }
.diagram-caption {
  font-family: var(--bb-font-mono);
  font-size: 0.72rem;
  color: var(--bb-text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-top: .85rem;
}

/* ---------- Forms ---------- */
.form-section {
  background: #fff;
  border: 1px solid var(--bb-line);
  padding: 2.5rem;
}
.form-section h2 { font-size: 1.45rem; margin-bottom: .35rem; }
.form-section .form-intro { color: var(--bb-text-muted); margin-bottom: 1.75rem; }
.form-label { font-weight: 500; font-size: .9rem; color: var(--bb-ink); }
.form-control, .form-select {
  border-radius: 0;
  border: 1px solid var(--bb-line-strong);
  padding: .65rem .85rem;
  font-size: 0.95rem;
}
.form-control:focus, .form-select:focus {
  border-color: var(--bb-ink);
  box-shadow: 0 0 0 3px rgba(20,198,214,0.18);
}
.form-check-input { border-radius: 0; border-color: var(--bb-line-strong); }
.form-check-input:checked { background-color: var(--bb-signal); border-color: var(--bb-signal); }
.opt-in-block {
  background: var(--bb-paper-2);
  border: 1px solid var(--bb-line);
  padding: 1rem 1.15rem;
  margin-top: 0.5rem;
}
.opt-in-block .form-check-label { font-size: .9rem; color: var(--bb-text); }

/* ---------- Tables / matrices ---------- */
.table-bb { width: 100%; border-collapse: collapse; }
.table-bb th, .table-bb td {
  text-align: left; padding: 0.85rem 1rem;
  border-bottom: 1px solid var(--bb-line);
  vertical-align: top;
}
.table-bb th {
  font-size: .8rem; letter-spacing: .08em; text-transform: uppercase;
  color: var(--bb-text-muted); font-weight: 600; border-bottom-color: var(--bb-line-strong);
}

/* ---------- Footer ---------- */
.bb-footer {
  background: var(--bb-navy-900);
  color: var(--bb-text-on-dark);
  padding: 4rem 0 2rem;
}
.bb-footer h6 { color: #fff; font-size: .78rem; letter-spacing: .12em; text-transform: uppercase; margin-bottom: 1rem; }
.bb-footer a { color: var(--bb-text-on-dark-muted); display: block; padding: .25rem 0; font-size: .92rem; }
.bb-footer a:hover { color: #fff; text-decoration: none; }
.bb-footer .footer-bottom {
  margin-top: 3rem; padding-top: 1.5rem;
  border-top: 1px solid rgba(255,255,255,0.12);
  display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 1rem;
  font-size: 0.85rem; color: var(--bb-text-on-dark-muted);
}
.bb-footer .footer-brand { display: flex; align-items: center; gap: .65rem; color: #fff; font-weight: 600; }

/* ---------- Filter chips (case studies) ---------- */
.chip-bar { display: flex; flex-wrap: wrap; gap: .5rem; }
.chip {
  border: 1px solid var(--bb-line-strong);
  background: #fff;
  color: var(--bb-text);
  padding: .4rem .85rem;
  font-size: .85rem;
  font-weight: 500;
  cursor: pointer;
  border-radius: 0;
  transition: all .15s ease;
}
.chip:hover { border-color: var(--bb-ink); }
.chip.active { background: var(--bb-ink); border-color: var(--bb-ink); color: #fff; }

/* ---------- Logo strip ---------- */
.logo-strip {
  display: grid; grid-template-columns: repeat(6, 1fr); gap: 2rem;
  align-items: center;
}
.logo-strip .logo-cell {
  font-family: var(--bb-font-mono);
  font-size: .85rem;
  color: var(--bb-text-on-dark-muted);
  text-align: center; padding: 1rem 0;
  border: 1px dashed rgba(255,255,255,0.12);
  letter-spacing: 0.04em;
}
@media (max-width: 768px) {
  .logo-strip { grid-template-columns: repeat(2, 1fr); }
}

/* ---------- Misc helpers ---------- */
.max-prose { max-width: 64ch; }
.section-heading { max-width: 36ch; }
.divider-thin { height: 1px; background: var(--bb-line); margin: 2rem 0; border: 0; }
.tag {
  display: inline-block; font-family: var(--bb-font-mono);
  font-size: .72rem; padding: .15rem .55rem;
  background: var(--bb-paper-2); border: 1px solid var(--bb-line);
  color: var(--bb-text-muted); letter-spacing: .04em;
}
.tag.tag-signal { background: rgba(20,198,214,0.08); border-color: rgba(20,198,214,0.35); color: var(--bb-signal-700); }

@media (max-width: 768px) {
  section { padding: 3.5rem 0; }
  .hero { padding: 4rem 0 3.5rem; }
  .def-list li { grid-template-columns: 1fr; gap: .25rem; }
  .form-section { padding: 1.75rem; }
}