:root {
  --navy: #0b2f57;
  --blue: #0284c7;
  --sky: #38bdf8;
  --ink: #102033;
  --muted: #64748b;
  --line: #dbe7f0;
  --soft: #f4f8fb;
  --white: #ffffff;
  --green: #0f766e;
  --warn: #b45309;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--white); line-height: 1.65; }
a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; height: auto; }
.skip-link { position: absolute; left: -999px; top: 8px; background: var(--navy); color: white; padding: 8px 12px; z-index: 10; }
.skip-link:focus { left: 8px; }
.site-header { position: sticky; top: 0; z-index: 5; background: rgba(255,255,255,.96); border-bottom: 1px solid var(--line); backdrop-filter: blur(10px); }
.header-inner { max-width: 1180px; margin: 0 auto; padding: 12px 20px; display: flex; align-items: center; gap: 18px; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--navy); font-size: 24px; font-weight: 850; letter-spacing: 0; }
.brand:hover { text-decoration: none; }
.brand img { width: 54px; height: 54px; object-fit: contain; display: block; border-radius: 4px; }
.nav { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; font-size: 14px; font-weight: 700; }
.nav a { color: var(--navy); }
.nav .primary { background: var(--navy); color: white; padding: 9px 13px; border-radius: 6px; }
.hero { background: linear-gradient(180deg, #ffffff 0%, #edf8ff 100%); border-bottom: 1px solid var(--line); }
.hero-inner { max-width: 1180px; margin: 0 auto; padding: 58px 20px 34px; display: grid; gap: 30px; grid-template-columns: 1.15fr .85fr; align-items: center; }
.hero h1 { margin: 0 0 14px; color: var(--navy); font-size: clamp(36px, 5vw, 64px); line-height: 1.02; letter-spacing: 0; }
.hero p { max-width: 670px; margin: 0 0 22px; color: #30445f; font-size: 19px; }
.hero-actions, .button-row { display: flex; flex-wrap: wrap; gap: 12px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 42px; padding: 10px 16px; border-radius: 6px; border: 1px solid var(--line); background: white; color: var(--navy); font-weight: 800; }
.button.primary { background: var(--blue); color: white; border-color: var(--blue); }
.network-card { background: white; border: 1px solid var(--line); border-radius: 8px; box-shadow: 0 18px 45px rgba(11,47,87,.12); padding: 22px; }
.network-card h2 { margin: 0 0 14px; color: var(--navy); font-size: 22px; }
.signal-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; }
.signal { border: 1px solid var(--line); background: var(--soft); border-radius: 6px; padding: 12px; font-weight: 800; color: var(--navy); }
.container { max-width: 1180px; margin: 0 auto; padding: 34px 20px; }
.section-title { display: flex; justify-content: space-between; align-items: end; gap: 18px; margin-bottom: 16px; }
.section-title h2, .page-title h1 { margin: 0; color: var(--navy); line-height: 1.12; }
.section-title p, .page-title p { margin: 8px 0 0; color: var(--muted); max-width: 760px; }
.grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.grid.two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.card { border: 1px solid var(--line); border-radius: 8px; background: white; padding: 18px; min-height: 100%; }
.card h3 { margin: 0 0 8px; color: var(--navy); line-height: 1.25; }
.card p { color: var(--muted); margin: 0 0 12px; }
.meta { color: var(--muted); font-size: 13px; font-weight: 700; }
.band { background: var(--soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.warning { border-left: 5px solid var(--warn); background: #fff7ed; padding: 15px 16px; border-radius: 6px; color: #713f12; }
.affiliate { border: 1px solid #bae6fd; background: #effaff; padding: 18px; border-radius: 8px; }
.affiliate strong { color: var(--navy); }
.breadcrumbs { font-size: 13px; color: var(--muted); margin-bottom: 16px; }
.layout { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 28px; align-items: start; }
.article { max-width: 800px; }
.article h1 { color: var(--navy); font-size: clamp(32px, 5vw, 52px); line-height: 1.08; margin: 0 0 12px; }
.article h2 { color: var(--navy); margin-top: 32px; line-height: 1.2; }
.article h3 { color: var(--navy); margin-top: 22px; }
.toc, .sidebar-box { border: 1px solid var(--line); border-radius: 8px; padding: 16px; background: white; }
.toc ol { margin: 8px 0 0 20px; padding: 0; }
.sidebar { position: sticky; top: 90px; display: grid; gap: 14px; }
table { width: 100%; border-collapse: collapse; margin: 16px 0; background: white; border: 1px solid var(--line); }
th, td { padding: 11px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
th { color: var(--navy); background: #edf8ff; }
.tool-panel { border: 1px solid var(--line); border-radius: 8px; padding: 18px; background: white; }
.tool-panel label { display: block; font-weight: 800; color: var(--navy); margin-top: 12px; }
.tool-panel input, .tool-panel select, .tool-panel textarea { width: 100%; min-height: 42px; border: 1px solid var(--line); border-radius: 6px; padding: 9px 10px; font: inherit; }
.tool-panel button { margin-top: 14px; min-height: 42px; border: 0; border-radius: 6px; background: var(--blue); color: white; padding: 10px 14px; font-weight: 800; cursor: pointer; }
.result { margin-top: 14px; border: 1px solid #bae6fd; border-radius: 6px; background: #effaff; padding: 12px; color: var(--navy); }
.footer { background: var(--navy); color: #dbeafe; margin-top: 42px; }
.footer a { color: white; }
.footer-inner { max-width: 1180px; margin: 0 auto; padding: 30px 20px; display: grid; grid-template-columns: 1.2fr repeat(3, 1fr); gap: 20px; }
.footer h2, .footer h3 { color: white; margin: 0 0 10px; }
.small { font-size: 13px; color: var(--muted); }
.footer .small { color: #bfdbfe; }
.not-found { text-align: center; padding: 70px 20px; }
@media (max-width: 860px) {
  .header-inner { align-items: flex-start; flex-direction: column; }
  .hero-inner, .layout, .grid, .grid.two, .footer-inner { grid-template-columns: 1fr; }
  .hero-inner { padding-top: 36px; }
  .sidebar { position: static; }
  .brand { font-size: 22px; }
  .brand img { width: 50px; height: 50px; }
  .nav { gap: 10px; }
  .network-card { box-shadow: none; }
}