styles.css

*{
    list-style: none;
    text-decoration: none;
    border-collapse: collapse;
    margin: 0px;
    padding: 0px;
    color: black; 
    font-family: 'Open Sans', sans-serif;
}

a{
    color: white;
    font-size: 20px;
    line-height: 20px;
}


/*---------------------------------------*/

.intro_bg{
    background-image: url("image/dna-5543033_1920.jpg");
    background-color: rgb(71, 70, 70);
    background-repeat: no-repeat;
    background-blend-mode:multiply ;
    background-size: 100% 100%;
    width: 100%;
    height: 620px;
    margin: auto;
    padding-bottom: 100px;
}

.header{
    width: 1280px;
    height: 86px;
    margin: auto;


}

.nav{
    display: flex;
    justify-content: center;
    width: 1280px;
    height: 100px;
}
.nav>li{
    margin: 40px auto auto auto;
    width: 280px;
    height: 30px;
    text-align: center;
    line-height: 33px;
    border: 3px solid floralwhite;
    border-radius: 13px;
    box-shadow: 0px 0px 10px rgba(4, 46, 124, 0.603);
}

.nav>li>a{
    font-weight: 400;
}


.nav > li > ul  {
    padding-top: 9px;
    text-align: center;
    font-size: 12px;
    font-weight: 100;
}

.nav > li > ul >li {
    display: none;
    margin-top: 7px;
}
.nav >li>ul>li>a{
    font-size: 15px;
    font-weight: 300;

}

.nav > li:hover >ul > li{
    display: block;
} 

.introtext1 {
    width: 1280px;
    height: 150px;
    margin: auto;
}

.introtext {
    width: 1280px;
    height: 400px;
    margin: auto;   
}


.introtext > div {
    margin: auto;
    width: 1150px;
    height: 380px;
    background-color: rgba(78, 78, 78, 0.356);
    opacity: 1;
    border-top: 3px solid seashell;
    border-bottom: 3px solid seashell;
    border-radius: 3px;
    position: relative;
    top: 50px;
}
.introtext > div> ul> li{
    margin-left: 30px;
    margin-top: 30px;
    margin-right: 30px;
    margin-bottom: 20px;
}
.introtext > div> ul> li > h1{
    color: whitesmoke;
    font-weight: bold;
}
.introtext > div> ul> li > h3{
    color: whitesmoke;
    font-weight: 400;
}
.introtext > div> ul> li > h5{
    color: whitesmoke;
    font-weight: 400;
}

/* ------------------------------------- */
.abouth{
    background: linear-gradient(#080e1b,#28395e) ;
    width: 100%;
    height: 620px;
    padding-bottom: 150px;
    margin: auto;
}

.about{
    width: 1280px;
    height: 86px;
    padding-top: 50px;
    margin: auto auto 0px auto;
}

.abouth > .about > h1 {
    text-align: left;
    padding-left: calc(1280px - 1195px);
    font-size: 40px;
    color: whitesmoke;
    text-shadow:0px 0px 10px rgba(1, 25, 68, 0.603);
}

.main1{
    width: 1200px;
    height: 320px;
    border: 1px solid whitesmoke;
    border-radius: 20px;
    margin: auto;
    margin-bottom: 100px;
    margin-top: 30px;

}

.main1 li {
    margin-top: 20px;
    margin-left: 30px;
    padding-top: 30px ;
}



.main1 h2,h4,h6{
    display: inline;
    color: whitesmoke;
    margin: 10px 5px auto 0px;
}
.main1 h2{
    font-size: 27px;
    font-weight: 450;
}
.main1 h4{
    font-size: 23px;
    font-weight: 400;
}
.main1 h6{
    font-size: 18px;
    font-weight: 350;
}
.italic{
    font-style: italic;
}
.main1>ul>li:last-child>h4{
    font-size: 22px;
}
/*---------------------------------------*/

.SA{
    background: linear-gradient(#1f2f4e,#505b72 ) ;
    width: 100%;
    height: 600px;
    padding-bottom: 150px;
    margin: auto;
}

.top, .bot{
    width: 1280px;
    height: 86px;
    margin: 0px auto auto auto;
    padding-top: 50px;
}

.SA>.top> h1 {
    text-align: left;
    padding-left: calc(1280px - 1195px);
    font-size: 40px;
    color: whitesmoke;
    text-shadow:0px 0px 10px rgba(1, 25, 68, 0.603);
}

.SA>.bot> h1 {
    text-align: left;
    padding-left: calc(1280px - 1195px);
    font-size: 40px;
    color: whitesmoke;
    text-shadow:0px 0px 10px rgba(1, 25, 68, 0.603);
}

.bot h1,h3{
    display: inline;
}
.bot h3{
    margin-left: 30px;
}


.main2{
    width: 1200px;
    height: 230px;
    border: 1px solid whitesmoke;
    border-radius: 20px;
    margin: auto;
    margin-top: 30px;


}

.main2 > ul> li {
    margin-left: 30px;
    padding-top: 10px;
}
.main2 h2,h3,h4{
    display: inline;
    color: rgb(255, 251, 251);
    margin: 10px 5px auto 0px;
}
.main2 h2{
    font-weight: 450;
    font-size: 23px;
}

.main2 h3{
    font-weight: 400;
}
.main2 h4{
    font-weight: 350;
}


.main3{
    width: 1200px;
    height: 130px;
    border: 1px solid whitesmoke;
    border-radius: 30px;
    margin: auto;
    margin-bottom: 100px;
    margin-top: 20px;

}
.main3 > ul> li {
    margin-left: 30px;
    padding-top: 30px;
}
.main3 > ul> li:last-child {
    margin-left: 30px;
    padding-top: 10px;
}


.main3 h2,h3,h5{
    display: inline;
    color: rgb(255, 251, 251);
    margin: 10px 5px auto 0px;
}

.main3 > ul>li>h2{
    font-weight: 400;

}
.main3 a{
    font-size: 19px;
    font-weight: 350;
    text-decoration-line: underline;
}
/*----------------------------------------*/
.exp{
    background: linear-gradient(#505b72,#85888d ) ;
    width: 100%;
    height: 600px;
    padding-bottom: 150px;
    margin: auto;
}

.exptop{
    width: 1280px;
    height: 86px;
    margin: 0px auto auto auto;
    padding-top: 50px;
}
.exptop> h1 {
    text-align: left;
    padding-left: calc(1280px - 1195px);
    font-size: 40px;
    color: whitesmoke;
    text-shadow:0px 0px 10px rgba(1, 25, 68, 0.603);
}

.main4{
    width: 1200px;
    height: 500px;
    border: 1px solid whitesmoke;
    border-radius: 20px;
    margin: auto;
    margin-bottom: 100px;
    margin-top: 30px;
}

.main4 li {
    margin-top: 20px;
    margin-left: 30px;
    padding-top: 5px ;
}

.main4>ul>li>h2{
    font-weight: 450;
    color: whitesmoke;
}
.main4>ul>li>h4{
    font-weight: 400;
    color: whitesmoke;
}
.main4>ul>li>h5{
    font-weight: 400;
    color: whitesmoke;
}
.samsung>h2{
    display: inline;
    margin-right: 5px;
}
.samsung h3{
    font-weight: 400;
}
.samsung h5{
    font-weight: 430;
    margin-left: 20px;
    margin-top: 10px;
}