:root {
  --bg: #ffffff;
  --bg-alt: #f5f5f7;
  --border-subtle: #e1e1e6;
  --text-main: #111827;
  --text-muted: #6b7280;
  --accent: #2563eb;
  --accent-soft: #e0ecff;
  --accent-dark: #1d4ed8;
  --danger: #f97373;
  --warn: #d97706;
  --radius-md: 8px;
  --radius-lg: 14px;
  --shadow-soft: 0 14px 40px rgba(15, 23, 42, 0.08);
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

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

html,
body {
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg);
  color: var(--text-main);
  -webkit-font-smoothing: antialiased;
}

.container {
  width: 100%;
  max-width: 1040px;
  margin: 0 auto;
  padding: 0 16px;
}

.site-header {
  border-bottom: 1px solid var(--border-subtle);
  background-color: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 10;
}

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

.logo {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
  color: var(--text-main);
  gap: 8px;
}

.logo-mark {
  width: 22px;
  height: 22px;
  border-radius: 6px;
  background: radial-gradient(circle at 20% 20%, #3b82f6, #1e40af);
}

.logo-text {
  font-weight: 600;
  letter-spacing: 0.02em;
  font-size: 15px;
}

.nav {
  display: flex;
  gap: 16px;
}

.nav-link {
  font-size: 14px;
  text-decoration: none;
  color: var(--text-muted);
  padding: 6px 10px;
  border-radius: 999px;
}

.nav-link:hover {
  color: var(--text-main);
  background-color: var(--bg-alt);
}

.nav-link-active {
  color: var(--accent-dark);
  background-color: var(--accent-soft);
}

.hero {
  padding: 40px 0 32px;
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2.6fr);
  gap: 32px;
  align-items: center;
}

.hero-copy h1 {
  font-size: 32px;
  line-height: 1.15;
  margin: 0 0 16px;
}

.hero-subtitle {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.6;
  margin: 0 0 8px;
}

.hero-actions {
  margin-top: 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 9px 18px;
  border-radius: 999px;
  background-color: var(--accent);
  color: #ffffff;
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  box-shadow: 0 12px 30px rgba(37, 99, 235, 0.3);
  border: none;
}

.btn-primary:hover {
  background-color: var(--accent-dark);
}

.hero-note {
  font-size: 12px;
  color: var(--text-muted);
}

.hero-panel {
  background-color: #0f172a;
  color: #e5e7eb;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
  overflow: hidden;
  font-size: 13px;
}

.panel-header {
  height: 32px;
  display: flex;
  align-items: center;
  padding: 0 12px;
  gap: 6px;
  background: linear-gradient(90deg, #020617, #0b1120);
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 999px;
  display: inline-block;
}

.dot-red { background-color: #f97373; }
.dot-amber { background-color: #fbbf24; }
.dot-green { background-color: #22c55e; }

.panel-body {
  padding: 14px 14px 16px;
}

.panel-metric {
  margin-bottom: 10px;
  border-bottom: 1px solid rgba(148, 163, 184, 0.2);
  padding-bottom: 8px;
}

.panel-metric:last-of-type {
  border-bottom: none;
  margin-bottom: 12px;
}

.metric-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: #9ca3af;
  margin-bottom: 2px;
}

.metric-value {
  font-size: 18px;
  font-weight: 600;
}

.metric-value.metric-ok {
  color: #4ade80;
}

.metric-footnote {
  font-size: 11px;
  color: #9ca3af;
}

.metric-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 3px 8px;
  border-radius: 999px;
  font-size: 11px;
}

.metric-badge-ok {
  background-color: rgba(22, 163, 74, 0.1);
  color: #4ade80;
}

.metric-badge-warn {
  background-color: rgba(217, 119, 6, 0.16);
  color: #fed7aa;
}

.panel-code {
  margin: 0;
  margin-top: 10px;
  padding: 8px 10px;
  background: #020617;
  border-radius: 8px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 11px;
  overflow-x: auto;
  color: #e5e7eb;
}

.section {
  padding: 32px 0 40px;
  background-color: var(--bg);
}

.section:nth-of-type(odd) {
  background-color: var(--bg-alt);
}

.section-title {
  font-size: 22px;
  margin: 0 0 8px;
}

.section-intro {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
  max-width: 720px;
  margin: 0 0 8px;
}

.features-grid {
  margin-top: 24px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.feature-card {
  background-color: #ffffff;
  border-radius: var(--radius-md);
  padding: 16px 16px 18px;
  border: 1px solid var(--border-subtle);
}

.feature-card h3 {
  margin: 0 0 8px;
  font-size: 16px;
}

.feature-card p {
  margin: 0 0 6px;
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.6;
}

.narrow { max-width: 720px; }

.narrow h1 {
  font-size: 26px;
  margin-bottom: 10px;
}

.narrow h2 {
  font-size: 18px;
  margin-top: 22px;
  margin-bottom: 6px;
}

.narrow p {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-main);
  margin: 0 0 8px;
}

.contact-list {
  list-style: none;
  padding: 6px 0 2px;
  margin: 0 0 10px;
}

.contact-list li {
  font-size: 14px;
  color: var(--text-main);
  margin-bottom: 4px;
}

.contact-list a {
  color: var(--accent-dark);
  text-decoration: none;
}

.contact-list a:hover {
  text-decoration: underline;
}

.back-link {
  margin-top: 20px;
  font-size: 14px;
}

.back-link a {
  color: var(--accent-dark);
  text-decoration: none;
}

.site-footer {
  border-top: 1px solid var(--border-subtle);
  padding: 12px 0;
  background-color: #ffffff;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.footer-left {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.footer-brand {
  font-size: 13px;
  font-weight: 500;
}

.footer-meta {
  font-size: 12px;
  color: var(--text-muted);
}

.footer-right {
  display: flex;
  gap: 12px;
}

.footer-link {
  font-size: 13px;
  color: var(--text-muted);
  text-decoration: none;
}

.footer-link:hover {
  color: var(--text-main);
}

.error-page {
  background-color: var(--bg-alt);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.error-main {
  width: 100%;
  max-width: 420px;
  padding: 16px;
}

.error-box {
  background-color: #ffffff;
  border-radius: var(--radius-lg);
  padding: 24px 22px 22px;
  box-shadow: var(--shadow-soft);
  text-align: center;
}

.error-box h1 {
  margin: 0 0 4px;
  font-size: 40px;
}

.error-box p {
  margin: 4px 0;
  font-size: 14px;
}

.error-hint {
  color: var(--text-muted);
  font-size: 13px;
  margin-bottom: 16px;
}

@media (max-width: 768px) {
  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
  }

  .hero {
    padding-top: 24px;
  }

  .hero-copy h1 {
    font-size: 26px;
  }

  .features-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .site-header {
    position: static;
  }

  .header-inner {
    padding: 10px 0;
  }
}

@media (max-width: 480px) {
  .hero-copy h1 {
    font-size: 24px;
  }

  .hero-panel {
    font-size: 12px;
  }
}