.header {
    background-image: url("../img/TTS/S01/TTS01_BG.d19a0484eb51.jpg");
    background-repeat: no-repeat;
    background-size: cover;
    padding-top: 0;
    padding-bottom: 0;
    background-position: bottom;
}

.section-head h2, .section-head p {
    margin-bottom: 0.5rem;
}

.section-head {
    display: flex;
    flex-flow: wrap;
}

.display-4 {
    padding-right: 8px;
}

@media (min-width: 768px) {
    .section-head h2, .section-head p {
        margin-bottom: 1rem;
    }
}

/*section2*/
.list-group {
    display: -ms-flexbox;
    display: flex;
    -ms-flex-direction: column;
    flex-direction: column;
    padding-left: 0;
    margin-bottom: 0
}

.list-group-item {
    position: relative;
    display: block;
    padding: .75rem 1.25rem;
    background-color: #fff;
    border: none;
}

.timeline .timeline-panel {
    padding-left: 10px;
}

.timeline-inverted .timeline-panel {
    padding-right: 10px;
}

.timeline-panel {
    position: relative;
    height: 350px;
}

.timeline-image, .timeline-content {
    -ms-flex: 0 0 75%;
    flex: 0 0 75%;
    max-width: 75%;
}

.timeline-content {
    z-index: 1;
    position: absolute;
    padding-top: 40%;
    font-size: 0.8rem;
}

.timeline-content .timeline-heading, .timeline-content .timeline-body {
    background-color: white;
}

.timeline-content .timeline-heading h3 {
    font-size: 1.5rem;
}

.timeline-image img {
    width: 100%;
}

.timeline .timeline-panel .timeline-image {
    position: absolute;
    right: 0;
    padding-left: 20px;
}

.timeline-inverted .timeline-panel .timeline-image {
    position: absolute;
    left: 12%;
    padding-right: 20px;
}

.timeline-inverted .timeline-panel .timeline-content {
    position: absolute;
    right: 0%;
}

@media (min-width: 768px) {
    .timeline-content .timeline-heading h3 {
        font-size: 1.76rem;
    }

    .timeline-image img {
        width: 80%;
    }

    .timeline-content {
        font-size: 1rem;
    }

    .timeline-image, .timeline-content {
        -ms-flex: 0 0 50%;
        flex: 0 0 50%;
        max-width: 50%;
    }

    .timeline .timeline-panel .timeline-content {
        position: absolute;
        right: 50%;
        padding: 50px 5px 0px 50px;
    }

    .timeline-inverted .timeline-panel .timeline-image img {
        margin-left: 12.5%;
    }

    .timeline-inverted .timeline-panel .timeline-content {
        position: absolute;
        right: -10%;
        padding: 50px 50px 0px 10px;
    }
}

#I01_01 {
    position: absolute;
    background-image: url("../img/TTS/S02/TTS02_I01_01.54649e8a1af3.png");
    background-repeat: no-repeat;
    background-size: contain;
    width: 60%;
    height: 60%;
    top: 5%;
}

#I01_02 {
    position: absolute;
    background-image: url("../img/TTS/S02/TTS02_I01_02.2f0a5305f362.png");
    background-repeat: no-repeat;
    background-size: contain;
    width: 95%;
    height: 45%;
    top: 50%;
}

#I01_ele {
    position: absolute;
    background-image: url("../img/TTS/S02/TTS02_I01_ele.56f946e75091.png");
    background-repeat: no-repeat;
    background-size: contain;
    width: 100%;
    height: 100%;
    top: 0;
    left: 4px;
}

@media (min-width: 768px) {
    #I01_01 {
        width: 150px;
        height: 150px;
        top: 20px;
    }

    #I01_02 {
        width: 230px;
        height: 100px;
        top: 130px;
    }

    #I01_ele {
        width: 250px;
        height: 250px;
        top: 0;
        left: -5px;
    }
}

@media (min-width: 992px) {
    #I01_01 {
        width: 200px;
        height: 200px;
        top: 35px;
    }

    #I01_02 {
        width: 315px;
        height: 150px;
        top: 170px;
    }

    #I01_ele {
        width: 300px;
        height: 300px;
        top: 0;
    }
}

@media (min-width: 1200px) {
    #I01_01 {
        width: 215px;
        height: 215px;
    }

    #I01_02 {
        width: 400px;
        height: 125px;
    }

    #I01_ele {
        width: 350px;
        height: 350px;
        top: 0;
        left: -10px
    }
}

#I02_01 {
    position: absolute;
    background-image: url("../img/TTS/S02/TTS02_I02_01.eb0bfdc2dd11.png");
    background-repeat: no-repeat;
    background-size: contain;
    width: 70%;
    height: 70%;
    top: 20%;
    left: 20%;
}

#I02_ele {
    position: absolute;
    background-image: url("../img/TTS/S02/TTS02_I02_ele.54e755e09c94.png");
    background-repeat: no-repeat;
    background-size: contain;
    width: 110%;
    height: 110%;
    top: -5%;
}

@media (min-width: 768px) {
    #I02_01 {
        width: 75%;
        height: 75%;
        top: 20%;
        left: 25%;
    }

    #I02_ele {
        width: 115%;
        height: 115%;
        top: -5%;
        left: 10%;
    }
}

/*section3*/
.list-group-item {
    margin-top: 60px;
}

.item-panel {
    position: relative;
    height: 550px;
    box-sizing: border-box;
}

@media (min-width: 768px) {
    .item-panel {
        height: 400px;
    }
}

.item-image {
    -ms-flex: 0 0 50%;
    flex: 0 0 50%;
    max-width: 50%;
    position: absolute;
    left: 0;
}

.item-image img {
    width: 100%;
    box-sizing: border-box;
}

.item-content {
    -ms-flex: 0 0 100%;
    flex: 0 0 100%;
    /*max-width: 100%;*/
    position: absolute;
    top: 200px;
    box-sizing: border-box;
}

.item-content p {
    font-size: 0.76rem;
}

#item-panel-02 {
    height: 1000px;
}

@media (min-width: 768px) {
    .item-image {
        -ms-flex: 0 0 25%;
        flex: 0 0 25%;
        max-width: 25%;
    }

    .item-content {
        -ms-flex: 0 0 75%;
        flex: 0 0 75%;
        max-width: 75%;
        left: 25%;
        top: 0;
    }

    .item-image img {
        width: 60%;
    }

    .item-content p {
        font-size: 1rem;
    }

    #item-panel-02 {
        height: 700px;
    }

    #item-panel-02 .item-content {
        top: 0;
    }
}

@media (min-width: 992px) {

    #item-panel-02 {
        height: 650px;
    }

}

.B_book {
    position: absolute;
    background-image: url("../img/TTS/S03/TTS03_Book01_book.ac23695177d0.png");
    background-repeat: no-repeat;
    background-size: contain;
    top: 15%;
    right: -15%;
    width: 80%;
    height: 130%;

}

.B_ele {
    position: absolute;
    background-image: url("../img/TTS/S03/TTS03_Book01ele.6a21b88c1a6b.png");
    background-repeat: no-repeat;
    background-size: contain;
    width: 150%;
    height: 150%;
    top: -20%;
    left: -35%;
}

#B02_book {
    background-image: url("../img/TTS/S03/TTS03_Book02_book.0f1a230cc799.png");
}

#B02_ele {
    background-image: url("../img/TTS/S03/TTS03_Book02ele.79efbbe03c12.png");
}

@media (min-width: 768px) {
    .B_book {
        top: 15%;
        right: 0;
        width: 75%;
        height: 130%;

    }

    .B_ele {
        width: 150%;
        height: 150%;
        top: -25%;
        left: -35%;
    }
}

.col-6 .record-content .button-bg {
    position: absolute;
    background-color: #000f63;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    text-align: center;
    box-sizing: border-box;
    right: 0;
    margin-top: 15px;
}

.mic-button {
    position: absolute;
    top: 50%;
    left: 50%;
    margin-left: -16px;
    margin-top: -16px;
}

.section4 {
    background-color: #25242a;
}

.section4 .container {
    color: #FFFFFF;
}

.section4 .content-text {
    background-image: url("../img/TTS/S04/TTS04_Textbox_BG.fcdb059fd8e3.jpg");
    background-size: cover;
    background-repeat: no-repeat;
}

.record-text {
    display: flex;
    flex-flow: wrap;
}

.record-text .text {
    min-width: 180px;
    height: 100px;
}

@media (min-width: 768px) {
    .record-text .text {
        width: 370px;
    }
}

@media (min-width: 992px) {
    .record-text .text {
        min-width: 450px;
        max-width: 500px;
    }
}

.button-bg {
    position: relative;
    background-color: #9cdbff;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    text-align: center;
    box-sizing: border-box;
    margin-top: 25px;
}

.record-content .button-bg {
    margin-bottom: 45px;
    margin-top: -15px;
}

@media (min-width: 786px) {
    .record-content .button-bg {
        margin-left: 5px;
        margin-bottom: 0;
        margin-top: 15px;
    }
}