.about_section_1 {
    padding: 70px 0;
    background-position: center center;
    background-repeat: no-repeat;
    background-size: cover;
    position: relative;
}

.about_section_1::after {
    background-color: #000;
    opacity: 0.4;
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
}

.about_section_1 .section_head {
    position: relative;
    z-index: 2;
    text-align: left;
}

.about_section_1 .section_head .section_title {
    font-size: 48px;
}

.about_section_1 .section_head .section_title,
.about_section_1 .section_head .section_desc {
    color: #fff !important;
}

/* section 2 */
.about_section_2 .box-desc {
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.about-video {
    overflow: hidden;
    border-radius: 25px;
    margin-bottom: 40px;
}

.tnsm-item {
    border-radius: 20px;
    overflow: hidden;
    box-shadow: rgba(99, 99, 99, 0.2) 0px 2px 8px 0px;
    padding: 24px;
    height: 100%;
}

.tnsm-item img {
    height: 80px;
}

/*  */
.about_section_khachhang {
    padding: 60px 0;
}

.about_section_khachhang .doitac_item {
    margin-bottom: 20px;
    cursor: pointer;
}

.about_section_khachhang .doitac_item:hover {
    background-color: #fff;
}