* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #0d1117;
  --panel: #161b22;
  --panel-alt: #1e242c;
  --border: #2a323c;
  --text: #eef2f5;
  --muted: #8b98a5;
  --accent: #003366;
  --accent-hover: #004a8f;
}

html, body {
  background: var(--bg);
  color: var(--text);
  font-family: "Segoe UI", "Segoe UI Variable", sans-serif;
  min-height: 100%;
}

a {
  color: inherit;
}

.wrap {
  max-width: 880px;
  margin: 0 auto;
  padding: 0 24px;
}

header.site-header {
  border-bottom: 1px solid var(--border);
  background: var(--panel);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  gap: 16px;
  padding-top: 18px;
  padding-bottom: 18px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 16px;
  text-decoration: none;
}

.brand img {
  width: 28px;
  height: 28px;
}

nav.site-nav {
  margin-left: auto;
  display: flex;
  gap: 8px;
}

nav.site-nav a {
  text-decoration: none;
  color: var(--muted);
  font-size: 13px;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: 7px;
  transition: background 0.15s ease, color 0.15s ease;
}

nav.site-nav a:hover {
  background: var(--panel-alt);
  color: var(--text);
}

nav.site-nav a.active {
  background: var(--accent);
  color: #fff;
}

main {
  padding: 56px 0 40px;
}

.hero {
  text-align: center;
  padding: 24px 0 48px;
}

.hero img.hero-logo {
  width: 96px;
  height: 96px;
  margin-bottom: 20px;
}

.hero h1 {
  font-size: 34px;
  margin-bottom: 10px;
}

.hero p.tagline {
  color: var(--muted);
  font-size: 15px;
  max-width: 520px;
  margin: 0 auto 28px;
  line-height: 1.6;
}

.btn {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  font-weight: 700;
  font-size: 14px;
  padding: 14px 30px;
  border-radius: 9px;
  transition: background 0.15s ease, transform 0.1s ease;
}

.btn:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.btn.secondary {
  background: var(--panel-alt);
  border: 1px solid var(--border);
}

.btn.secondary:hover {
  background: var(--border);
}

.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 24px;
}

.feature-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
}

.feature-card h3 {
  font-size: 14px;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.5;
}

.download-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 36px;
  text-align: center;
}

.download-card .version {
  color: var(--muted);
  font-size: 12px;
  margin-top: 14px;
}

.notice {
  background: var(--panel-alt);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  padding: 16px 20px;
  margin-top: 28px;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.6;
  text-align: left;
}

.notice strong {
  color: var(--text);
}

h2.section-title {
  font-size: 20px;
  margin-bottom: 20px;
}

.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 20px 0;
}

.faq-item:first-child {
  padding-top: 0;
}

.faq-item h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.faq-item p {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.6;
}

footer.site-footer {
  border-top: 1px solid var(--border);
  padding: 24px 0 40px;
  text-align: center;
}

footer.site-footer p {
  font-size: 12px;
  color: var(--muted);
  line-height: 1.6;
  max-width: 560px;
  margin: 0 auto;
}

@media (max-width: 640px) {
  .features {
    grid-template-columns: 1fr;
  }
  nav.site-nav a {
    padding: 8px 10px;
  }
}