.m15 {
    margin: 15px;
}
.tc{
    text-align: center;
    font-size: 18px;
    font-weight: 600;
}
.container {
    margin-top: 2%;
    margin-left: 25%;
}
.cover{
    background-size: cover;
    height: 1080px;
    display: block;
    overflow: hidden;
    position: relative;
    text-align: center;
    padding-top: 50px;
    font-size: 50px;
}

.a{
    color: white;
    font-size: 15px;
    padding-top: 50px;
    position: relative;
}