*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
.avviso-width{
    display: none;
    background-color: #f00;
    color: #fff;
    text-align: center;
    padding: 10px;
    z-index: 999999999;
}
body{
    color: #0f0;
    background-color: #000;
    padding-top: 200px;
}
header{
    background-color: #444;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100px;
}
.btn-homepage{
    display: block;
    position: absolute;
    color: #000;
    top: 0;
    left: 0;
    text-align: center;
    font-size: 10px;
    width: 90px;
    height: 100px;
    padding: 10px;
}
.btn-homepage img{
    display: block;
    cursor: pointer;
    border: #000 solid 4px;
    border-radius: 18px;
    height: 70px;
    margin-bottom: 4px;
}
.btn-homepage img:hover{
    transition: 0.5s;
    border: #0f0 solid 1px;
}
.txt-header{
    display: flex;
    flex-direction: column;
    justify-content: center;
    width: 100%;
    height: 100%;
    margin-left: 150px;
    padding: 10px;
    font-size: 40px;
}
.up-btn{
    display: flex;
    justify-content: center;
    text-align: center;
    color: #0f0;
    background-color: #222;
    border: #000 solid 2px;
    box-shadow: 0 0 20px #0f0;
    border-radius: 10px;
    text-decoration: none;
    font-size: 20px;
    cursor: pointer;
    width: 20px;
    height: 20px;
    margin: 20px auto;
}
.div-img{
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    padding: 0 5%;
    margin-bottom: 100px;
}
.div-img img{
    width: 100%;
    max-width: 650px;
}
.div-img button{
    background-color: #000;
    cursor: pointer;
    border: none;
    padding: 10px;
}
.div-img button:hover{
    transition: 0.5s;
    background-color: #0f0;
}
.div-img-fullscreen{
    background-color: #000;
    position: fixed;
    display: none;
    flex-direction: column;
    justify-content: center;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}
.div-img-fullscreen img{
    width: auto;
    height: auto;
    max-width: 95%;
    max-height: 90%;
    margin: 0 auto;
}
.avviso{
    color: #f00;
    background-color: #000;
    font-size: 15px;
    position: fixed;
    top: 100px;
    width: 100%;
    padding: 10px;
}
a{
    color: rgb(255, 90, 90);
    font-weight: bold;
}
footer{
    position: fixed;
    color: gray;
    background-color: #000;
    border-radius: 10px 0 0 0;
    font-size: 15px;
    bottom: 1px;
    right: 1px;
    padding: 2px;
}

/* Pulsanti scorrimento immagini */
#close_btn{
    position: fixed;
    top: 10px;
    right: 10px;
    height: 40px;
    width: 40px;
    font-size: 30px;
    font-weight: bolder;
    border-radius: 10px;
    color: #0f0;
    background-color: #333;
    cursor: pointer;
}
.prev, .next{
    cursor: pointer;
    position: fixed;
    top: 50%;
    width: auto;
    padding: 16px;
    color: #0f0;
    background-color: #333;
    font-weight: bold;
    font-size: 20px;
    user-select: none;
}
.prev:hover, .next:hover, #close_btn:hover{
    transition: 1s ease;
    color: #000;
    background-color: #0f0;
}
.prev{
    left: 0;
    border-radius: 0 10px 10px 0;
}
.next{
    right: 0;
    border-radius: 10px 0 0 10px;
}

/* Ridimensionamenti width */
@media only screen and (max-width: 1200px){
    header{
        height: 80px;
    }
    .btn-homepage{
        height: 80px;
        width: 72px;
        padding: 8px;
    }
    .btn-homepage img{
        height: 56px;
        margin-bottom: 3px;
    }
    .txt-header{
        font-size: 30px;
        margin-left: 100px;
    }
    .avviso{
        top: 80px;
    }
}
@media only screen and (max-width: 500px){
    header{
        height: 60px;
    }
    .btn-homepage{
        cursor: default;
        width: 60px;
        height: 60px;
        padding: 5px;
    }
    .btn-homepage:hover{
        background-color: #444;
    }
    .btn-homepage img{
        height: 53px;
        cursor: pointer;
        border: #000 solid 3px;
        border-radius: 15px;
    }
    .btn-homepage span{
        display: none;
    }
    .txt-header{
        font-size: 25px;
        margin-left: 70px;
    }
    .avviso{
        top: 60px;
        font-size: 10px;
    }
    footer{
        font-size: 10px;
    }
}
@media only screen and (max-width: 300px) {
    header, .div-img, .div-img-fullscreen, .up-btn{
        display: none;
    }
    .avviso-width{
        display: block;
    }
}