*{
    margin: 0;
    padding: 0;
    box-sizing:  border-box;
    font-family: sans-serif;
}

body{
    background: #000;
    position: relative;
}

/* Landing div */
.header{
    position: relative;
    width: 100%;
    height: 100vh;
    color: #fff;
}

/* rmspc */
#logo{
    font-size: 1.2rem;
    font-weight: bolder;
    position: absolute;
    top: 20px;
    left: 20px;
}

/* Home button */
#top-button{
    background: transparent ; 
    border: 1px solid #fff;
    border-radius: 5px;
    font-size: 0.8rem;
    padding: 10px;
    position: absolute; 
    right: 20px; 
    top: 20px;
    color: #fff;
    outline:none;
    cursor: pointer;
}

/* Physique chimie lycee Galilee */
#legende{
    font-size: 0.6rem;
    position: absolute;
    bottom: 20px;
    left: 20px;
}

#fleche{
    font-size:1.5rem;
    position: absolute;
    bottom: 20px;
    right: 20px;
    color: rgb(100,100,100);
}

/* 2nde. */
#headline{
    font-size: 4rem;
    font-weight: bolder;
    position: absolute;
    top: 60vh;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #fff;
    z-index: 2;
}

/* Background */
.bg{
    position: absolute; 
    top: 0; 
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    box-shadow: inset 0px 20px 100px black, inset -20px 0px 100px black;
}

/* Black container of ressources and chapter */
section{
    padding: 35vh 0 10vh 0;
    color: #eee;
    min-height: 80vh;
    height: 100%;
    background: linear-gradient(180deg, rgba(0,0,0,0) 0%, rgba(0,0,0,1) 15%, rgba(0,0,0,1) 100%);
    position: relative;
    display:block;
}

/* Invisible container of ressources and chapters */
.container{
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    gap: 0.2rem;
    padding-bottom: 30px;
}

.container a{
    text-decoration: none;
    color: #000;
    display: block;
}

h1{
    padding-left: 10px;
    padding-bottom: 30px;
}

/* card of each ressource or chapter */
.card {
    background-color: #eee;
    width: 100%;
    height: 100px;
    display: flex;
    flex-direction: column;
}

.card img{
    object-fit: cover;
    min-height: 100%;
}

/* title of each card */
.titre{
    padding: 5%;
    transform: translateY(-100%);
    background-color: rgba(100,100,100,0.6);
    backdrop-filter: blur(2px);
    font-size: 0.8rem;
    color: #fff;
    font-family: 'Georgia', sans-serif;
}

@media screen and (min-width: 700px){
    #headline{
        font-size: 6rem;
    }

    #logo{
        font-size: 2rem;
    }

    #top-button{
        font-size: 1.2rem;
    }
    #fleche{
        font-size: 2rem;
    }
    #legende{
        font-size: 1rem;
    }

    .titre{
        font-size: 1rem;
    }

    section{
        padding: 35vh 20% 10vh 20%;
    }

    h1{
        padding-left: 0;
        font-size: 2rem;
    }

    .container{
        grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
    }

    .card{
        min-height: 200px;
    }
}