:root {
  --night: #0F172A;
  --night-soft: #1E293B;
  --lime: #A3E635;
  --lime-dim: #65A30D;
  --fog: #CBD5E1;
  --mute: #94A3B8;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Consolas", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  background: var(--night);
  color: var(--fog);
  line-height: 1.75;
}

a {
  color: var(--lime);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.wrap {
  width: min(1100px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  background: #020617;
  border-bottom: 1px solid #334155;
  position: sticky;
  top: 0;
  z-index: 20;
}

.site-header .wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 0;
}

.brand {
  color: var(--lime);
  font-weight: 700;
  letter-spacing: 0.08em;
}

.site-header nav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 16px;
  font-size: 13px;
}

.hero {
  padding: 40px 0 20px;
}

.hero h1 {
  margin: 0 0 14px;
  color: #F8FAFC;
  font-size: clamp(26px, 3.8vw, 38px);
  line-height: 1.35;
}

.hero p {
  margin: 0;
  max-width: 46em;
  color: var(--mute);
}

.clock-strip {
  margin: 10px 0 36px;
  padding: 22px 16px 18px;
  background: var(--night-soft);
  border: 1px solid #334155;
}

.clock-strip .label {
  color: var(--lime);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

.stepper {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 8px;
}

.stepper .tick {
  text-align: center;
  padding: 10px 6px 14px;
  border-top: 3px solid var(--lime-dim);
  position: relative;
}

.stepper .tick::before {
  content: "";
  width: 14px;
  height: 14px;
  border: 2px solid var(--lime);
  border-radius: 50%;
  display: block;
  margin: -20px auto 10px;
  background: var(--night);
}

.stepper .tick strong {
  display: block;
  color: #F8FAFC;
  font-size: 14px;
}

.stepper .tick span {
  display: block;
  color: var(--mute);
  font-size: 12px;
  margin-top: 4px;
}

.schematic {
  margin: 20px 0;
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 20px;
  align-items: center;
  background: #020617;
  border: 1px dashed #4B5563;
  padding: 18px;
}

.schematic .block {
  width: 148px;
  height: 148px;
  background: #6B7280;
  color: #111827;
  display: grid;
  place-items: center;
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.12em;
}

.schematic p {
  margin: 0;
  color: var(--mute);
}

section {
  margin: 0 0 46px;
}

section h2 {
  margin: 0 0 12px;
  color: var(--lime);
  font-size: 22px;
  font-weight: 600;
}

.card-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin: 18px 0;
}

.svg-card {
  background: var(--night-soft);
  border: 1px solid #334155;
  padding: 14px;
}

.svg-card svg {
  width: 100%;
  height: 92px;
  display: block;
}

.svg-card h3 {
  margin: 10px 0 6px;
  color: #F8FAFC;
  font-size: 16px;
}

.svg-card p {
  margin: 0;
  color: var(--mute);
  font-size: 14px;
}

.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.panel {
  background: #020617;
  border-left: 3px solid var(--lime);
  padding: 16px 18px;
}

.panel h3 {
  margin: 0 0 8px;
  color: #F8FAFC;
}

.steps {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.steps li {
  display: grid;
  grid-template-columns: 88px 1fr;
  gap: 12px;
  background: var(--night-soft);
  padding: 12px 14px;
}

.steps .t {
  color: var(--lime);
  font-variant-numeric: tabular-nums;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th, td {
  border: 1px solid #334155;
  padding: 10px 12px;
  text-align: left;
  vertical-align: top;
}

th {
  background: #020617;
  color: var(--lime);
}

.faq dt {
  margin: 18px 0 6px;
  color: #F8FAFC;
  font-weight: 700;
}

.faq dd {
  margin: 0;
  color: var(--mute);
}

.site-footer {
  border-top: 1px solid #334155;
  padding: 28px 0 36px;
  color: var(--mute);
  font-size: 14px;
}

.site-footer p {
  margin: 0 0 10px;
}

@media (max-width: 880px) {
  .stepper,
  .card-row,
  .two-col,
  .schematic,
  .steps li {
    grid-template-columns: 1fr;
  }

  .schematic .block {
    width: 120px;
    height: 120px;
  }
}