/* ===== Base Reset & Variables ===== */
:root {
  --primary: #1a7a4c;
  --primary-dark: #0f5c38;
  --primary-light: #e8f5ee;
  --accent: #f08c00;
  --accent-dark: #d47800;
  --text: #1a1a2e;
  --text-light: #5a5a6e;
  --bg: #ffffff;
  --bg-alt: #f5f7fa;
  --bg-dark: #1a1a2e;
  --border: #e0e4e8;
  --shadow: 0 4px 16px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
  --radius: 8px;
  --radius-lg: 16px;
  --transition: 0.3s ease;
  --max-width: 1200px;
  --header-h: 72px;
}

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

html { scroll-behavior: smooth; scroll-padding-top: var(--header-h); }

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--accent); }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* ===== Typography ===== */
h1, h2, h3, h4 { font-weight: 700; line-height: 1.3; color: var(--text); }
h1 { font-size: clamp(28px, 4vw, 44px); }
h2 { font-size: clamp(22px, 3vw, 32px); }
h3 { font-size: clamp(18px, 2vw, 22px); }
p { color: var(--text-light); }

/* ===== Buttons ===== */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 28px; border-radius: 6px; font-size: 15px; font-weight: 600;
  cursor: pointer; border: none; transition: all var(--transition);
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); color: #fff; transform: translateY(-1px); box-shadow: 0 4px 12px rgba(26,122,76,0.3); }
.btn-accent { background: var(--accent); color: #fff; }
.btn-accent:hover { background: var(--accent-dark); color: #fff; transform: translateY(-1px); box-shadow: 0 4px 12px rgba(240,140,0,0.3); }
.btn-outline { background: transparent; border: 2px solid #fff; color: #fff; }
.btn-outline:hover { background: #fff; color: var(--primary); }
.btn-sm { padding: 8px 18px; font-size: 14px; }

/* ===== Utility ===== */
.text-center { text-align: center; }
.text-primary { color: var(--primary); }
.text-accent { color: var(--accent); }
.section { padding: 80px 0; }
.section-alt { background: var(--bg-alt); }
.section-title {
  text-align: center; margin-bottom: 48px;
}
.section-title h2 { margin-bottom: 12px; }
.section-title p { max-width: 600px; margin: 0 auto; font-size: 16px; }
.section-title .bar {
  width: 48px; height: 4px; background: var(--accent); border-radius: 2px;
  margin: 16px auto 0;
}

/* ===== Page Hero ===== */
.page-hero {
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
  color: #fff; padding: 100px 0 60px; text-align: center;
}
.page-hero h1 { color: #fff; margin-bottom: 12px; }
.page-hero p { color: rgba(255,255,255,0.85); font-size: 18px; max-width: 600px; margin: 0 auto; }

/* ===== Cards ===== */
.card {
  background: #fff; border-radius: var(--radius-lg); padding: 32px;
  box-shadow: var(--shadow); transition: all var(--transition); border: 1px solid var(--border);
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: var(--primary-light); }
.card-icon {
  width: 56px; height: 56px; border-radius: 12px;
  background: var(--primary-light); color: var(--primary);
  display: flex; align-items: center; justify-content: center;
  font-size: 24px; margin-bottom: 20px;
}

/* ===== Grid ===== */
.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 24px; }
.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 24px; }
.grid-4 { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 24px; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .section { padding: 60px 0; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .page-hero { padding: 80px 0 40px; }
}