*{box-sizing: border-box;
    margin: 0;
    padding: 0;
    }
    
    body {
    font-family: 'Open Sans', sans-serif;
    background-color: rgba(0,0,0,.8); 
    }

    
    .wrapper{
        margin: 0 auto;
        width: 100%;
        max-width: 1200px;
    }
    
    
    nav {
        position: sticky;
        top: 0;
        z-index: 10;
        height: 60px;
        line-height: 60px;
        background-color: white;
        text-align: center;
    
    }
    .wrapper{
        margin: 0 auto;
        width: 100%;
        max-width: 1200px;
    }
    
    .burger-icon {
        display: block;
        margin-left: auto;
        padding: 0 30px;
        background: none;
        border: none;
        font-size: 30px;
        line-height: 60px;
        cursor: pointer;
    }
    
    .nav-items {
        display: none;
    }
    
    
    .nav-items a {
        padding: 0 30px;
        text-decoration: none;
        text-transform: uppercase;
        font-weight: bold;
        color: #333;
        transition: color 0.3s;
    }
    
    .nav-items a:hover {
        color: #09f;
    }
    
    
    .publications {
        position: relative;
        background-color:#333;
        background-size: cover;
        background-position: center;
        text-align: center;
        margin: 100px auto;
        color: honeydew;
    }
    
    .publications h3 {
        text-transform: uppercase;
    }
    
    .math{
        padding: auto;
       font-size: 20px;
       margin-bottom: 30px;
    }
    .publications span {
        text-transform: uppercase;
        color: #09f;
    }

    @media (min-width: 238px) {
        /* .burger-icon {
            display: none;
        } */
        .nav-items {
            display: block;
        }
    }