/* ========== 导航栏基础 ========== */
#mainNav {
  background: #ffffff !important;
  box-shadow: 0 2px 20px rgba(0,0,0,0.08);
  border-bottom: 1px solid #e8e8e8;
  font-weight: 500;
}

#mainNav .navbar-nav .nav-item {
  position: relative;
}

#mainNav .navbar-nav .nav-link {
  padding: 0.5rem 1.2rem;
  color: #333;
  font-size: 20px;
  transition: color 0.3s;
}

#mainNav .navbar-nav .nav-link:hover {
  color: #007bff;
}

#mainNav .navbar-nav .nav-item.active > .nav-link {
  color: #007bff !important;
}

/* ========== 全屏下拉菜单（fixed 全屏版） ========== */
.mega-dropdown {
  position: fixed;
  left: 0;
  right: 0;
  top: 71px;                    /* 根据导航栏实际高度调整 */
  width: 100vw;
  background: #ffffff;
  border-top: 3px solid #007bff;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.12);
  padding: 30px 0;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: all 0.3s ease;
  z-index: 1050;
  overflow: visible;
}

.nav-item:hover .mega-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.mega-dropdown:empty {
  display: none !important;
}

/* ========== 下拉菜单内部容器 ========== */
.mega-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.mega-row {
  display: flex;
  gap: 30px;
}



/* ===== 右侧内容列（网格） ===== */
.mega-col-content {
  flex: 1;
}

.mega-content-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.mega-content-item {
  background: #fafbfc;
  border-radius: 8px;
  transition: all 0.25s ease;
  border: 1px solid #f0f0f0;
}

.mega-content-item:hover {
  background: #f5f8ff;
  border-color: #007bff;
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(0, 123, 255, 0.10);
}

.mega-content-item a {
  display: flex;
  align-items: center;
  padding: 14px 16px;
  text-decoration: none;
  color: #333;
  gap: 14px;
}

.mega-icon-box {
  flex: 0 0 40px;
  width: 40px;
  height: 40px;
  background: #e8f0fe;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #007bff;
  font-size: 20px;
  transition: all 0.25s;
}

.mega-content-item:hover .mega-icon-box {
  background: #007bff;
  color: #fff;
}

.mega-info h5 {
  font-size: 20px;
  font-weight: 400;
  margin: 0 0 2px 0;
  color: #222;
}

.mega-info p {
  font-size: 20px;
  color: #999;
  margin: 0;
}

.mega-content-item:hover .mega-info p {
  color: #007bff;
}

/* ========== 移动端适配 ========== */
@media (max-width: 991.98px) {
  .mega-dropdown {
    position: static;
    top: auto;
    width: 100% !important;
    left: auto;
    right: auto;
    transform: none !important;
    box-shadow: none;
    border-top: none;
    border-left: 3px solid #007bff;
    padding: 10px 0 10px 15px;
    opacity: 1 !important;
    visibility: visible !important;
    background: transparent;
  }
  
  .mega-row {
    flex-direction: column;
    gap: 15px;
  }
  
  .mega-col-nav {
    flex: 1;
    border-right: none;
    padding-right: 0;
  }
  
  .mega-col-nav h4 {
    font-size: 15px;
  }
  
  .mega-content-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
  }
  
  .mega-content-item a {
    padding: 10px 12px;
  }
  
  .mega-icon-box {
    width: 32px;
    height: 32px;
    font-size: 20px;
  }
  
  .mega-info h5 {
    font-size: 13px;
  }
}
/* ===== 宽度满屏 ===== */
.container {
    max-width: 90% !important;
    padding-left: 0px;
    padding-right:0px;
}

/* 如果页面有 .container-fluid 或 .container-lg 等，一并处理 */
.container-fluid,
.container-lg,
.container-md,
.container-sm,
.container-xl {
    max-width: 100% !important;
    padding-left: 0px;
    padding-right: 0px;
}

/* 如果想让某些内容完全贴边（无内边距） */
.full-width {
    width: 100%;
    max-width: 100%;
    padding-left: 0;
    padding-right: 0;
}