.x_top_book{align-items:center;background:#fff;display:flex;height:44px;justify-content:space-between;padding:0 16px}.x_top_book .x_top_c{align-items:center;display:flex;justify-content:center}.x_top_book .x_top_c .logo{background:url(../favicon.ico) no-repeat 0;background-size:100%;text-indent:-100vw;width:28px}.x_top_book .x_top_c.btn a{align-items:center;border:1px solid #cad5e2;box-sizing:border-box;color:#314158;display:flex;font-size:12px;height:30px;justify-content:center;width:46px}.x_top_book .x_top_c.btn a:nth-of-type(n+2){border-left:0}.x_top_book .x_top_c.btn a:first-of-type{border-radius:6px 0 0 6px}.x_top_book .x_top_c.btn a:last-of-type{border-radius:0 6px 6px 0}.x_top_book{box-shadow:0 1px #eee;box-sizing:border-box;max-width:750px;min-width:320px;position:fixed;top:0;width:100%;z-index:999}.x_top_book .title{left:50%;position:absolute;transform:translate(-50%)}.plhd{height:44px}