/* ========================================
   重置样式 + 12列Grid栅格系统
   ======================================== */

/* ---------- 基础重置 ---------- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans SC', sans-serif;
  line-height: 1.6;
  color: #1a1a2e;
  background: #f7f8fa;
  -webkit-font-smoothing: antialiased;
}

img, svg {
  display: block;
  max-width: 100%;
}

a {
  text-decoration: none;
  color: inherit;
}

ul, ol {
  list-style: none;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font: inherit;
}

/* ---------- Grid 栅格系统 ---------- */
.g-container {
  width: 100%;
  max-width: 1600px;
  margin: 0 auto;
  padding-left: 0;
  padding-right: 0;
}

.g-row {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 20px;
}

/* 列跨度 */
.g-col-1  { grid-column: span 1; }
.g-col-2  { grid-column: span 2; }
.g-col-3  { grid-column: span 3; }
.g-col-4  { grid-column: span 4; }
.g-col-5  { grid-column: span 5; }
.g-col-6  { grid-column: span 6; }
.g-col-7  { grid-column: span 7; }
.g-col-8  { grid-column: span 8; }
.g-col-9  { grid-column: span 9; }
.g-col-10 { grid-column: span 10; }
.g-col-11 { grid-column: span 11; }
.g-col-12 { grid-column: span 12; }

/* 响应式：平板缩减 */
@media (max-width: 1024px) {
  .g-col-md-1  { grid-column: span 1; }
  .g-col-md-2  { grid-column: span 2; }
  .g-col-md-3  { grid-column: span 3; }
  .g-col-md-4  { grid-column: span 4; }
  .g-col-md-5  { grid-column: span 5; }
  .g-col-md-6  { grid-column: span 6; }
  .g-col-md-7  { grid-column: span 7; }
  .g-col-md-8  { grid-column: span 8; }
  .g-col-md-9  { grid-column: span 9; }
  .g-col-md-10 { grid-column: span 10; }
  .g-col-md-11 { grid-column: span 11; }
  .g-col-md-12 { grid-column: span 12; }
}

/* 响应式：手机 */
@media (max-width: 768px) {
  .g-row {
    gap: 12px;
  }
  .g-col-sm-1  { grid-column: span 1; }
  .g-col-sm-2  { grid-column: span 2; }
  .g-col-sm-3  { grid-column: span 3; }
  .g-col-sm-4  { grid-column: span 4; }
  .g-col-sm-5  { grid-column: span 5; }
  .g-col-sm-6  { grid-column: span 6; }
  .g-col-sm-7  { grid-column: span 7; }
  .g-col-sm-8  { grid-column: span 8; }
  .g-col-sm-9  { grid-column: span 9; }
  .g-col-sm-10 { grid-column: span 10; }
  .g-col-sm-11 { grid-column: span 11; }
  .g-col-sm-12 { grid-column: span 12; }
}

/* ---------- Grid 特化布局：自动填充网格 ---------- */
.g-auto {
  display: grid;
  gap: 16px;
}
.g-auto-5 {
  grid-template-columns: repeat(5, 1fr);
}
.g-auto-4 {
  grid-template-columns: repeat(4, 1fr);
}
.g-auto-3 {
  grid-template-columns: repeat(3, 1fr);
}
.g-auto-2 {
  grid-template-columns: repeat(2, 1fr);
}