/* ========== CSS Variables ========== */
:root {
  --color-primary: #00A8E8;
  --color-primary-light: rgba(0, 168, 232, 0.08);
  --color-primary-medium: rgba(0, 168, 232, 0.15);
  --color-accent: #E74C3C;
  --color-accent-hover: #C0392B;
  --color-purple: #8B5CF6;
  --color-green: #27AE60;
  --color-cyan: #00BCD4;
  --color-bg-white: #FFFFFF;
  --color-bg-gray: #F8FAFC;
  --color-text-primary: #1E293B;
  --color-text-secondary: #475569;
  --color-text-tertiary: #64748B;
  --color-border: #E2E8F0;
  --color-success: #10B981;

  --font-family: "Microsoft YaHei", "PingFang SC", "Inter", -apple-system, BlinkMacSystemFont, sans-serif;

  --radius-card-lg: 20px;
  --radius-card-sm: 16px;
  --radius-btn: 40px;
  --radius-tag: 40px;

  --shadow-card: 0 8px 24px rgba(0, 168, 232, 0.06);
  --shadow-card-hover: 0 16px 32px rgba(0, 168, 232, 0.12);
  --shadow-nav: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);

  --transition-fast: 0.2s ease-out;
  --transition-normal: 0.3s ease-out;

  --max-width: 1280px;
  --section-gap: 100px;
}

/* ========== Reset & Base ========== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }
body { font-family: var(--font-family); font-weight: 400; font-size: 16px; line-height: 1.6; color: var(--color-text-primary); background: var(--color-bg-white); overflow-x: hidden; }
a { text-decoration: none; color: inherit; transition: color var(--transition-fast); }
ul, ol { list-style: none; }
img { max-width: 100%; display: block; }
button { border: none; cursor: pointer; font-family: inherit; font-size: inherit; transition: all var(--transition-fast); }

/* ========== Utility ========== */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }
.section { padding: var(--section-gap) 0; }
.section--gray { background: var(--color-bg-gray); }

.fade-in { opacity: 0; transform: translateY(30px); transition: opacity 0.6s ease-out, transform 0.6s ease-out; }
.fade-in.visible { opacity: 1; transform: translateY(0); }

.section__header { text-align: center; margin-bottom: 64px; }
.section__label { display: inline-flex; align-items: center; padding: 6px 16px; background: var(--color-primary-light); color: var(--color-primary); font-size: 14px; font-weight: 500; border-radius: var(--radius-tag); margin-bottom: 16px; }
.section__title { font-size: 36px; font-weight: 700; color: var(--color-text-primary); margin-bottom: 16px; letter-spacing: -0.02em; }
.section__desc { font-size: 16px; color: var(--color-text-tertiary); max-width: 600px; margin: 0 auto; }

.btn-primary { display: inline-flex; align-items: center; gap: 8px; padding: 14px 32px; background: var(--color-accent); color: #fff; font-size: 16px; font-weight: 600; border-radius: var(--radius-btn); border: none; cursor: pointer; transition: all var(--transition-fast); }
.btn-primary:hover { background: var(--color-accent-hover); transform: translateY(-2px); box-shadow: 0 8px 20px rgba(231, 76, 60, 0.3); }
.btn-secondary { display: inline-flex; align-items: center; gap: 8px; padding: 14px 32px; background: var(--color-bg-white); color: var(--color-primary); font-size: 16px; font-weight: 600; border-radius: var(--radius-btn); border: 2px solid var(--color-primary); cursor: pointer; transition: all var(--transition-fast); }
.btn-secondary:hover { background: var(--color-primary); color: #fff; transform: translateY(-2px); box-shadow: 0 8px 20px rgba(0, 168, 232, 0.25); }

.img--card { width: 100%; border-radius: var(--radius-card-lg); box-shadow: var(--shadow-card); }
.img--full { width: 100%; display: block; }
.img--cover { width: 100%; height: 100%; object-fit: cover; border-radius: var(--radius-card-lg); }

@media (max-width: 1023px) {
  .section__title { font-size: 28px; }
  .section__desc { font-size: 14px; }
  .section { padding: 64px 0; }
  .section__header { margin-bottom: 40px; }
}

@media (max-width: 767px) {
  .section__title { font-size: 24px; }
  .section { padding: 48px 0; }
  .container { padding: 0 16px; }
}