.contents{
    height: 100vh;
    background: linear-gradient(0deg, rgb(22, 22, 22), rgb(255, 70, 70));
    background-repeat: no-repeat;
    background-size: cover;
    background-position: center;
}
header{
    text-align: center;
    background-color: rgb(255, 70, 70);
    padding: 15px;
}
.header_title{
    user-select: none;
    font-size: 75px;
    font-weight: 500;
}
.header_subtitle{
    font-size: 25px;
    font-weight: 400;
}
footer{
    padding: 20px;
}
hr{
    height: 1px;
    border: none;
    background: linear-gradient(to right, rgba(0, 0, 0, 0), rgba(255, 70, 70, 0.6), rgba(0, 0, 0, 0));
}
small{
    color: rgb(180, 180, 180);
    font-size: 15px;
}
.window{
    background-color: rgb(255, 255, 255);
    max-width: 800px;
    padding: 10px;
    margin: 20px auto;
    border-radius: 15px;
    transition: .5s ease;
}
.window-contents{
    font-size: 25px;
    color: rgb(255, 70, 70);
}
.window_title{
    background-color: rgb(255, 70, 70);
    color: rgb(255, 255, 255);
    font-weight: 500;
    padding-left: 10px;
    font-size: 40px;
    border-top-left-radius: 15px;
    border-top-right-radius: 15px;
}
.window_tag{
    user-select: none;
    font-size: 20px;
    display: inline-block;
    background-color: rgb(255, 70, 70);
    padding: 0 5px;
    border-bottom-left-radius: 10px;
    border-bottom-right-radius: 10px;
    vertical-align: top;
    transition: .5s ease;
}
.window_tag:hover{
    font-size: 30px;
    background-color: rgb(190, 35, 35);
}
.window_a{
    text-align: center;
    background-color: rgb(255, 70, 70);
    color: rgb(255, 255, 255);
    padding: 10px;
    font-size: 25px;
    display: block;
    margin-left: auto;
    margin-right: 0;
    transition: .5s ease;
    text-decoration: none;
    border-radius: 15px;
    max-width: 100px;
}
.window_a:hover{
    background-color: rgb(190, 35, 35);
    color: rgb(255, 255, 255);
}