@import url("https://fonts.googleapis.com/css2?family=Geist:wght@400;500;600;700&display=swap");

:root {
  color-scheme: light;
  --background: #ffffff;
  --foreground: #0a0a0a;
  --card: #ffffff;
  --primary: #1d4ed8;
  --primary-foreground: #fafafa;
  --muted: #f5f5f5;
  --muted-foreground: #737373;
  --border: #e5e5e5;
  --ring: #a3a3a3;
  --radius: 8px;
  --radius-card: 10px;
  --elevation-sm: 0 1px 2px 0 rgb(0 0 0 / 5%);
  --elevation-lg: 0 10px 15px -3px rgb(0 0 0 / 10%), 0 4px 6px -4px rgb(0 0 0 / 10%);
  font-family: "Geist", sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--background); color: var(--foreground); }
a { color: inherit; }

.site-header {
  min-height: 68px;
  display: grid;
  grid-template-columns: minmax(max-content, 1fr) auto minmax(max-content, 1fr);
  align-items: center;
  gap: 24px;
  padding: 12px clamp(20px, 5vw, 72px);
  border-bottom: 1px solid var(--border);
  background: rgb(255 255 255 / 94%);
}

.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; }
.brand-mark { display: grid; place-items: center; width: 34px; height: 34px; border-radius: var(--radius); color: #fff; background: var(--primary); font-size: 21px; font-weight: 700; }
.brand-name { font-size: 18px; font-weight: 600; letter-spacing: -0.03em; white-space: nowrap; }
.brand-name strong { font-weight: 800; }
.header-nav { display: flex; align-items: center; justify-content: center; gap: clamp(16px, 2.4vw, 32px); }
.header-nav a { color: var(--muted-foreground); font-size: 13px; font-weight: 500; text-decoration: none; white-space: nowrap; }
.header-nav a:hover { color: var(--foreground); }
.header-link { justify-self: end; font-size: 14px; font-weight: 600; color: var(--primary); text-decoration: none; white-space: nowrap; }
.header-link:hover { text-decoration: underline; }

.eyebrow { margin: 0 0 12px; color: var(--primary); font-size: 12px; line-height: 1.3; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; }
h1, h2, h3, p { text-wrap: pretty; }

.content-section { width: min(1120px, calc(100% - 40px)); margin: 0 auto; padding: 64px 0; }
.topics-section { padding-top: 58px; }
.section-heading { display: flex; justify-content: space-between; align-items: end; gap: 32px; margin-bottom: 30px; }
.section-heading h1, .section-heading h2, .support-panel h2 { margin: 0; font-size: clamp(28px, 4vw, 40px); line-height: 1.1; letter-spacing: -0.04em; }
.section-heading > p { max-width: 380px; margin: 0; color: var(--muted-foreground); line-height: 1.6; }

.topic-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.topic-card { min-height: 170px; display: grid; grid-template-columns: auto 1fr auto; align-items: start; gap: 18px; padding: 24px; border: 1px solid var(--border); border-radius: var(--radius-card); background: var(--card); box-shadow: var(--elevation-sm); text-decoration: none; transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease; }
.topic-card:hover { border-color: #cbd5e1; box-shadow: var(--elevation-lg); transform: translateY(-2px); }
.topic-card:focus-visible, summary:focus-visible, a:focus-visible { outline: 3px solid color-mix(in srgb, var(--primary) 35%, transparent); outline-offset: 3px; }
.topic-card strong { display: block; margin: 4px 0 10px; font-size: 17px; }
.topic-card small { display: block; color: var(--muted-foreground); font-size: 14px; line-height: 1.55; }
.topic-icon { color: var(--primary); font-size: 12px; font-weight: 700; }
.arrow { color: var(--muted-foreground); font-size: 18px; }

.faq-section { padding-top: 28px; }
.faq-group { scroll-margin-top: 24px; margin-top: 42px; border-top: 1px solid var(--border); }
.faq-group h3 { margin: 0; padding: 28px 0 14px; font-size: 14px; letter-spacing: 0.02em; }
details { border-bottom: 1px solid var(--border); }
summary { position: relative; padding: 22px 44px 22px 0; cursor: pointer; list-style: none; font-weight: 600; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; position: absolute; right: 6px; top: 17px; color: var(--muted-foreground); font-size: 24px; font-weight: 400; }
details[open] summary::after { content: "−"; }
.answer-content { padding: 0 0 30px; color: var(--muted-foreground); }
.answer-content > p { max-width: 820px; margin: -4px 0 20px; line-height: 1.7; }
.answer-content strong { color: var(--foreground); }
.answer-content ol, .answer-content ul { max-width: 820px; margin: 0 0 24px; padding-left: 24px; line-height: 1.75; }
.answer-split { display: grid; grid-template-columns: minmax(0, 1fr) 230px; align-items: start; gap: 38px; }
.help-figure { margin: 8px 0 0; overflow: hidden; border: 1px solid var(--border); border-radius: var(--radius-card); background: var(--muted); box-shadow: var(--elevation-sm); }
.help-figure img { display: block; width: 100%; height: auto; }
.help-figure figcaption { padding: 11px 14px; border-top: 1px solid var(--border); background: var(--card); color: var(--muted-foreground); font-size: 12px; line-height: 1.45; }
.help-figure-wide { max-width: 836px; }
.help-figure-portrait { max-width: 230px; margin-top: 0; }
.control-list { columns: 2; column-gap: 44px; }
.vehicle-layout { display: grid; grid-template-columns: 230px minmax(0, 1fr); align-items: start; gap: 28px; max-width: 900px; }
.status-card { overflow: hidden; margin-top: 8px; border: 1px solid var(--border); border-radius: var(--radius-card); background: var(--card); box-shadow: var(--elevation-sm); }
.status-card > div { display: grid; grid-template-columns: 12px 58px 1fr; align-items: center; gap: 9px; padding: 11px 13px; border-bottom: 1px solid var(--border); font-size: 13px; }
.status-card > div:last-child { border-bottom: 0; }
.status-dot { width: 10px; height: 10px; border-radius: 50%; }
.status-moving { background: #22c55e; }
.status-idling { background: #f59e0b; }
.status-stationary { background: #3b82f6; }
.status-offline { background: #ef4444; }
.content-note { padding: 15px 17px; border: 1px solid #dbe4ff; border-radius: var(--radius); background: #f4f7ff; }

.support-panel { width: min(1120px, calc(100% - 40px)); margin: 10px auto 84px; display: flex; align-items: center; justify-content: space-between; gap: 40px; padding: clamp(28px, 5vw, 52px); border: 1px solid #dbe4ff; border-radius: var(--radius-card); background: #f4f7ff; }
.support-panel p:last-child { max-width: 650px; margin: 16px 0 0; color: var(--muted-foreground); line-height: 1.6; }
.button { flex: 0 0 auto; display: inline-flex; min-height: 42px; align-items: center; justify-content: center; padding: 10px 18px; border-radius: var(--radius); color: var(--primary-foreground); background: var(--primary); box-shadow: var(--elevation-sm); text-decoration: none; font-size: 14px; font-weight: 600; }
.button:hover { background: #1e40af; }

footer { min-height: 80px; display: flex; align-items: center; justify-content: space-between; gap: 24px; padding: 20px clamp(20px, 5vw, 72px); border-top: 1px solid var(--border); color: var(--muted-foreground); font-size: 13px; }

@media (max-width: 1040px) {
  .site-header { grid-template-columns: 1fr auto; }
  .header-nav { grid-column: 1 / -1; grid-row: 2; padding-top: 8px; border-top: 1px solid var(--border); }
  .topic-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 820px) {
  .topic-card { min-height: 130px; }
  .section-heading, .support-panel { align-items: flex-start; flex-direction: column; }
  .answer-split, .vehicle-layout { grid-template-columns: 1fr; }
  .help-figure-portrait { max-width: 280px; }
}

@media (max-width: 620px) {
  .site-header { min-height: 62px; }
  .header-nav { justify-content: flex-start; overflow-x: auto; padding-bottom: 4px; }
  .topic-grid { grid-template-columns: 1fr; }
  .content-section { padding: 58px 0; }
  .section-heading { align-items: flex-start; flex-direction: column; }
  .control-list { columns: 1; }
  footer { align-items: flex-start; flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; }
}