* {
    margin: 0;
    padding: 0;
    border: 0;
    box-sizing: border-box;

}

a {
    text-decoration: none;
}

ul,
li,
ol {
    list-style: none;
}

body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    height: 100vh;
}

header {
    height: 150px;
    width: 100%;
    background: url(../images/ist3.jpeg);
    background-repeat: no-repeat;
    background-size: 100% 150px;
    z-index: 1;
    position: fixed;
}

header img {
    width: 150px;
}

.navbar {
    margin-top: 20px;
    float: right;
    display: block;
    height: 100px;


}

.navbar-menu li {

    display: inline-block;
    border-right: 1px solid #000;
    padding: 20px;
    margin-top: 30px;
    transition: 300ms all;


}

.navbar-menu li:first-child {
    border-left: 1px solid #000;
}

.navbar-menu li:last-child {
    border-right: none;
    margin-right: 10px;
}

.navbar-menu li a {
    color: #FFF;
    font-size: 18px;
    font-weight: 700;

}

.navbar-li-committess ol li {
    margin-top: -20px;
}

.navbar-li-general ol li {
    margin-top: -20px;
}

.navbar-li-key-dates ol li {
    margin-top: -20px;
}

.navbar-li-co-located ol li {
    margin-top: -20px;
}

.navbar-li-previous-edution ul li {
    margin-top: -30px;
    border: none;
}

.navbar-menu-general,
.navbar-menu-committes,
.navbar-menu-key-dates,
.navbar-menu-co-located,
.navbar-menu-previous-edution {
    position: absolute;
    display: none;
    color: white;
    background-color: rgba(0, 0, 0, 0.6);
    border: none;


}

.navbar-menu-general {
    right: 1px;
    margin-top: 18px;

}

.navbar-menu-committes {
    left: 0.3px;
    margin-top: 18px;
}

.navbar-menu-key-dates {
    margin-top: 18px;
    left: 0px;
}

.navbar-menu-co-located {
    margin-top: 18px;
    right: 20px;
}

.navbar-menu-previous-edution {
    width: 200px;
    border: none;
    padding-top: 10px;
}




.navbar-menu-general li a {
    font-size: 14px;
}

.navbar-menu-committes li a {
    font-size: 14px;
}

.navbar-menu-key-dates li a {
    font-size: 14px;
}

.navbar-menu-co-located li a {
    font-size: 14px;
}

.navbar-menu-previous-edution li a {
    font-size: 12px;
}




.navbar-menu-committes {
    left: 0.3px;
    margin-top: 18px;
}

.navbar-menu-key-dates {
    margin-top: 18px;
    left: 0px;
}

.navbar-menu-co-located {
    margin-top: 18px;
    right: 20px;
}

.navbar-menu-previous-edution {
    left: 0.3px;
    margin-top: 18px;
}

.navbar-li-general:hover .navbar-menu-general {
    display: block;
}

.navbar-li-committess:hover .navbar-menu-committes {
    display: block;

}

.navbar-li-key-dates:hover .navbar-menu-key-dates {
    display: block;
}

.navbar-li-co-located:hover .navbar-menu-co-located {
    display: block;
}

.navbar-li-previous-edution:hover .navbar-menu-previous-edution {
    display: block;
}

[class^="navbar-li-"]:hover {
    transform: scale(1.2);
    background-color: rgba(0, 0, 0, 0.6);

}

.little-menu {
    margin-top: -13px;
    width: 100%;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.89);
    font-size: 20px;
    color: #FFF;
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: 300ms all;
    display: none;

}

.little-menu-list li {
    margin-top: 10px;

    text-align: center;


}

.little-menu-list-general-li,
.little-menu-list-committess-li,
.little-menu-list-key-dates-li,
.little-menu-list-co-located-li,
.little-menu-list-general-li-previous-edutions {
    display: none;

}

[class^="little-menu-list-"]:hover {
    background-color: rgba(255, 255, 255, 0.6);

}

.little-menu-list-general:hover .little-menu-list-general-li {

    display: block;
}

.little-menu-list-committess:hover .little-menu-list-committess-li {

    display: block;
}

.little-menu-list-key-dates:hover .little-menu-list-key-dates-li {
    display: block;
}

.little-menu-list-co-located:hover .little-menu-list-co-located-li {
    display: block;
}

.little-menu-list-general-li-2:hover .little-menu-list-general-li-previous-edutions {
    display: block;
}

.navbar-button {
    background: none;
    float: right;
    font-size: 30px;
    margin-right: 30px;
    margin-top: 30px;
    color: #FFF;
    display: none;
}

.navbar-button:active {
    transform: rotate(90deg);
    transition: 400ms all;
}

.little-menu.active {
    display: block;
}




.footer {
    display: inline-block;
    background-color: rgb(107, 107, 107);
    width: 100%;
    height: 200px;
    text-align: center;

}

.footer-all-icons {
    margin-top: 10px;
    margin-bottom: 20px;

}

.footer-all-icons div {
    display: inline;
}

.footer-all-icons div a {
    background-color: #FFF;
    color: #000;
    border-radius: 50%;
    font-size: 40px;
    display: inline-flex;
    width: 80px;
    height: 80px;
    flex-wrap: nowrap;
    margin-right: 30px;
    justify-content: center;
    align-items: center;
    transition: 425ms all;
}

.footer-icon-twitter:hover a {
    transform: scale(1.3);
    background-color: #1DA1F2;
    color: #FFF;


}

.footer-icon-facebook:hover a {
    transform: scale(1.3);
    background-color: #3b5998;
    color: #FFF;
}

.footer-copyright {
    width: 100%;
    background-color: #F53;
}

.footer-all-copyright {
    text-align: center;
    display: flex;
    justify-content: center;
    font-size: 11px;
}

.section {
    width: 100%;
    height: auto;
    background-color: white;
    font-size: 24px;
    text-align: center;
}

.section-img {
    height: 150px;
    width: 100%;
    opacity: 0.9;
    background: url(../images/ist3.jpeg);
    background-size: 100% 150px;
    background-repeat: no-repeat;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 0;

}


.section-text {
    margin: 20px auto 0 auto;
    font-size: 18px;
    width: 60%;
}

.keynote-1,
.keynote-2,
.keynote-3 {
    background-color: rgba(143, 143, 143, 0.6);
    width: 100%;
    height: auto;
    border: 1px solid #000;
    border-radius: 10px;
    margin-top: 20px;

}

.keynote-1-img,
.keynote-2-img,
.keynote-3-img {
    margin-top: 30px;
    margin-left: 30px;
    border: 1px solid #000;
    height: 100px;
    width: 20%;
    float: left;
}

.keynote-1-abstract,
.keynote-2-abstract,
.keynote-3-abstract {
    margin-top: 30px;
    margin-left: 30px;

    height: auto;
    width: 60%;
    float: left;
}

.clear {
    clear: both;
}

.keynote-1-biography,
.keynote-2-biography,
.keynote-3-biography {
    margin: 50px auto 30px auto;

    height: auto;
    width: 90%;
}

@media (max-width:1778px) {
    .navbar-menu li a {
        font-size: 14px;
    }

    .navbar-menu-general {
        left: 1px;
        margin-top: 18px;

    }

    .navbar-menu-previous-edution li {
        font-size: 10px;
    }

    .navbar-li-committess ol li {
        margin-top: -30px;
    }

    .navbar-li-general ol li {
        margin-top: -30px;
    }

    .navbar-li-key-dates ol li {
        margin-top: -30px;
    }

    .navbar-li-co-located ol li {
        margin-top: -30px;
    }

    .navbar-li-previous-edution ul li {
        margin-top: -35px;
        border: none;
    }

    .navbar-menu-general li a {
        font-size: 12px;
    }

    .navbar-menu-committes li a {
        font-size: 12px;
    }

    .navbar-menu-key-dates li a {
        font-size: 12px;
    }

    .navbar-menu-co-located li a {
        font-size: 12px;
    }
}


@media (max-width:1600px) {
    .navbar-button {
        display: block;
    }


    .navbar-menu {
        display: none;
    }

}


@media (max-width:600px) {

    .footer-all-icons div a {
        width: 50px;
        height: 50px;
        font-size: 30px;

    }
}

@media (max-width:1200px) {

    .keynote-1-biography,
    .keynote-2-biography,
    .keynote-3-biography {
        margin-top: 70px;

    }
}

@media (max-width:1150px) {

    .keynote-1-biography,
    .keynote-2-biography,
    .keynote-3-biography {
        margin-top: 90px;

    }

}

@media (max-width:900px) {

    .keynote-1,
    .keynote-2,
    .keynote-3 {
        font-size: 14px;
    }

}



@media (max-width:600px) {

    .keynote-1,
    .keynote-2,
    .keynote-3 {
        height: 750px;
    }

    .keynote-1-biography,
    .keynote-2-biography,
    .keynote-3-biography {
        margin-top: 130px;

    }

    .keynote-1-abstract,
    .keynote-2-abstract,
    .keynote-3-abstract {

        height: 100px;
        width: 80%;
        margin: 50px auto
    }

    .keynote-1-img,
    .keynote-2-img,
    .keynote-3-img {
        margin-top: 30px;
        margin-left: 30px;

        width: 70px;
    }

}

@media (max-width:460px) {
    .footer-all-icons div a {
        width: 30px;
        height: 30px;
        font-size: 10px;

    }


}