:root {
  --bg: #0b0f1a;
  --bg-alt: #11162a;
  --text: #e6ebff;
  --muted: #a8b0c9;
  --primary: #4f7cff;
  --card: #161b33;
  --border: #233052;
}

/* light theme */
:root.light {
  --bg: #f7f8fb;
  --bg-alt: #ffffff;
  --text: #1c2237;
  --muted: #5f6b86;
  --primary: #365cfb;
  --card: #ffffff;
  --border: #e6e9f2;
}

* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Inter", system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  line-height: 1.6;
}

.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg-alt);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 60px;
}
.brand { font-weight: 700; letter-spacing: .2px; }
.nav { display: flex; gap: 14px; align-items: center; }
.nav a { color: var(--text); text-decoration: none; font-weight: 600; opacity: .9; }
.nav a:hover { color: var(--primary); }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 12px;
  cursor: pointer;
  text-decoration: none;
}
.btn.ghost { background: transparent; }
.btn.primary { background: var(--primary); border-color: var(--primary); color: #fff; }
.btn:hover { filter: brightness(1.1); }

.hero {
  background: linear-gradient(120deg, rgba(79,124,255,.08), transparent 60%), var(--bg);
  border-bottom: 1px solid var(--border);
}
.hero-inner { padding: 64px 0; text-align: center; }
.hero h1 { font-size: 36px; margin: 0 0 10px; }
.hero p { color: var(--muted); margin: 0 auto 20px; max-width: 720px; }
.hero-actions { display: flex; gap: 12px; justify-content: center; }

.section { padding: 36px 0; }
.section h2 { margin: 0 0 14px; font-size: 24px; }
.section p { color: var(--muted); }

.grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px 16px;
  box-shadow: 0 1px 1px rgba(0,0,0,0.06);
}
.card h3 { margin-top: 0; }
.card ul { margin: 8px 0 0 18px; }
.card li { margin: 6px 0; }
.card a { color: var(--primary); text-decoration: none; }
.card a:hover { text-decoration: underline; }

.resources .card ul { columns: 1; }

.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 24px;
}
.site-footer .container { padding: 18px 0; }
.site-footer p { color: var(--muted); margin: 0; text-align: center; }

@media (max-width: 860px) {
  .grid { grid-template-columns: 1fr; }
  .nav { flex-wrap: wrap; gap: 10px; }
}

/* 新能源场景图片样式 */
.card img {
  width: 100%;
  height: auto;
  border: 1px solid var(--border);
  border-radius: 8px;
  display: block;
}