/* body{
    margin: 0;
}
.nav-bar{
    list-style: none;
    margin:0;
    padding: 0;
    background-color: #333;
    overflow: hidden;
    position: fixed;
    top: 0;
    width: 100%;
}

.nav-con{
    display: inline;
    float: left;
}

.nav-con a{
    color: white;
    text-decoration: none;
    display: block;
    text-align: center;
    padding: 14px 16px;
}
.nav-con a:hover{
    background-color: #111;
}*/

.active{
    background-color: #ffffff;
    color: black;
} 
h1{
    text-align: center;
    background-repeat: no-repeat;
    background-size: 100%;
    height: 100px;
    word-spacing: 2px;
    color: white;
    padding-top: 54px;
    font-size: 42px;
}
button{
    width: 92px;
    height: 40px;
    margin: 20px 15px;
    border: 0px;
    border-radius: 10px;
    font-size: revert;
    background-color: #333333;
}

a{
    color:white;
    font-weight: normal;
    text-decoration: none;
}
a:hover{
    color:white;
}
button:hover{
    background-color: #111 ;
}
button:focus{
    outline: none;
}

/* communication lecture */
#communication{
    /* margin-top: 92px; */
    text-align: center;
    background-color: #e6e6e6;
    /* display: none; */
}

#communication h1{
    background-color: #ff8474;
}
/* analog circuit */
#analog{
    margin-top: 74px;
    text-align: center;
    background-color: #e6e6e6;
    /* display: none; */
}

#analog h1{
    background-color: #ff8474;
}
/* network theory */
#network{
    /* margin-top: 92px; */
    text-align: center;
    background-color: #e6e6e6;
    /* display: none; */
}

#network h1{
    background-color: #ff8474;
}
/* digital electronics */
#digital{
    /* margin-top: 92px; */
    text-align: center;
    background-color: #e6e6e6;
    /* display: none; */
}
#digital h1{
    background-color: #ff8474;
}

/* electronics device */
#electronics{
    /* margin-top: 92px; */
    text-align: center;
    background-color: #e6e6e6;
    /* display: none; */
}
#electronics h1{
    background-color: #ff8474;
}
/* mathematics */
#math{
    text-align: center;
    background-color: #e6e6e6;
}
#math h1{
    background-color: #ff8474;
}
/* control system */
#control{
    text-align: center;
    background-color: #e6e6e6;
}
#control h1{
    background-color: #ff8474;
}
/* signal and system */
#signal{
    text-align: center;
    background-color: #e6e6e6;
}
#signal h1{
    background-color: #ff8474;
}
/* electromagnetic field theory */
#emft{
    text-align: center;
    background-color: #e6e6e6;
}
#emft h1{
    background-color: #ff8474;
}