body{
    margin: 0px;    
    width: 100%;
    background: linear-gradient(to top, rgba(0,0,0,0.5)50%,rgba(0,0,0,0.5)50%), url(../images/bg.png);
    background-attachment: fixed;
    background-position: center;
    background-size: cover;
    backdrop-filter: blur(3px);
    height: 109vh;
}
main{
    margin-left: 20px;
    margin-right: 20px;
}
h1{
    color: rgb(255, 255, 255);
    text-align: center;
    margin-top: 60px;
}
h3 {
    color: aliceblue;
    font-size: 20px;
  }
p{
    color: rgb(255, 255, 255);
    font-size: 20px;
}
li{
    color: rgb(255, 255, 255);
    font-size: 20px;
}
b{
    color: white;
}
.navbar{
    background-color: hsl(0, 0%, 22%);
    position: relative;
    display: flex;
    align-items: center;
    height: 80px;
    font-size: 20px;
}
.nav-left {
    margin-right: auto;
}

.nav-center {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);

    display: flex;
    align-items: center;
}
.navbar ul li:first-child {
  margin-right: auto;
}
.navbar ul li:not(:first-child) {
  justify-self: center;
}
.navbar a{
    color: rgb(255, 255, 255);
    text-decoration: none;
    padding: 0 15px;
    margin: 0;
    display: flex;
    text-align: center;
    height: 70px;
    align-items: center;
}
.navbar a.selected {
    background-color: hsl(0, 0%, 17%);
}
.navbar a:hover{
    background-color: hsl(0, 0%, 10%);
}
.navbar .nav-left a:hover{
    background-color: hsl(0, 0%, 22%);
}
.navbar li{
    float: left;
}
.alert {
    position: relative;
    padding: .75rem 1.25rem;
    margin-bottom: 1rem;
    border: 1px solid transparent;
    border-radius: .25rem;
    margin: 0;
}
.alert-error {
    color: #721c24;
    background-color: #f8d7da;
    border-color: #f5c6cb;
}
.alert-success {
    color: #155724;
    background-color: #d4edda;
    border-color: #c3e6cb;
}