.header_title {
   background-image: url('../admin/img/a8efa096a3e122a5521faa5665b91629.jfif');
}
.logo {
   background-image: url('../assets/images/logo_ca.png');
}
.container-contact100 {
   background-image: url("../admin/img/a8efa096a3e122a5521faa5665b91629.jfif");
}
 <!-- background-image: linear-gradient(176deg, rgb(115, 82, 248) 0%, rgba(128,52,236, .5) 100%), url('../admin/img/a8efa096a3e122a5521faa5665b91629.jfif'); -->