.header_box {
    width: 100%;
    padding: calc(1px + 1rem) 0;
    background-color: #ffffff;
}

.header {
    max-width: 1400px;
    width: 85%;
    margin: auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header_logo {
    width: calc(50px + 5rem);
}
.header_logo img{
    width: 100%;
}

.header_nav{
    display: flex;
    justify-content: flex-end;
    align-items: center;
    gap: calc(14px + 5rem);
}
.header_nav .nav_item a{
font-family: Microsoft YaHei;
font-weight: 400;
font-size: calc(8px + 0.5rem);
color: #2C3136;
line-height: calc(6px + 1.5rem);
}

.header_nav .header_active a{
color: #295C95;
border-bottom: 1px #295C95 solid;
}