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

.main {
  width: 100%;
  position: relative;
}

.main .bg-img {
  width: 100%;
  object-fit: contain;
  line-height: 1;
  font-size: 0;
}

.btn {
  position: absolute;
  left: 0;
  right: 0;
  width: 100%;
  bottom: 350px;
  text-decoration: none;
}
.main .btn-img {
  width: 100%;
  object-fit: contain;
  line-height: 1;
  font-size: 0;
}

/* 基本的页脚样式 */
.footer {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 36px;
  text-align: center;
}

.footer a,
.footer .copyright {
  color: #fff;
  font-size: 14px;
  text-shadow: 0 1px 1px #000;
  text-decoration: none;
}

#container {
  background-color: red;
}