.bannerC{ width: 100%; position: relative; aspect-ratio: 10 / 3; z-index: 1;}
.bannerC img{ display: block; width: 100%; height: 100%; object-fit: cover;}
.bannerC span{ display: inline-block; position: absolute; top: 50%; left: 2rem; transform: translateY(-50%);  color: #fff; font-size:.7rem; font-family: 黑体; text-shadow: 0 0 0.25rem rgba(0,0,0,.7); font-weight: bold; }