header {
    height:44px;
    width:100%;
    background: linear-gradient(90deg, #1975ad, #18469b);
    color: #fff;
    margin-bottom: 6%;
    /*display: flex;*/
    /*justify-content: space-between;*/
    /*align-items: center;*/
    position: fixed;
    top: 0;
    z-index:999;
    line-height: 44px;
}

header a {
    color: #fff;
    text-decoration: none;
}
header .header_page_title{
    font-size:19px;
    font-weight: bold;
    text-align: center;
    vertical-align: middle;
}

header .header_btn_back{
    background-image: image-set(var(--btn-back));
    background-repeat: no-repeat;
    background-size: 25px 25px;
    background-position: center center;
    position: absolute;
    top: 4px;
    left: 12px;
    height: 34px;
    width: 34px;
}

header .header_btn_back img {
  height: 100%;
  width: auto;
 }

a.btn_goIndex {
    background-image: image-set(var(--btn-go-index));
    background-repeat: no-repeat;
    background-size: 25px 25px;
    background-position: center center;
    position: absolute;
    top: 4px;
    right: 12px;
    height: 34px;
    width: 34px;
}