body, html{
    width: 100%;
    height: 100%;
    overflow: hidden;
    background: linear-gradient(#f0f0f0, #808080);
    margin: 0;
    padding: 0;
}
.header{
    height: 30px;
    padding: 5px 20px;
    background: #e0e0e0;
    overflow: hidden;
    box-sizing: border-box;
}
.header__install-theme-message{
    float: right;
    color: #f08080;
    font-size: 16px;
}
.header__menu{
    float: left;
}
.header__menu-item{
    display: inline-block;
    margin-right: 30px;
}
.main{
    padding: 10px 20px;
    box-sizing: border-box;
    height: calc(100% - 30px);
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* ************************************************ *
 *                      Логин                       *
 ************************************************** */

.login-popup{
    padding: 10px 20px;
    background: #e0e0e0;
    border: 1px solid #a0a0a0;
    box-sizing: border-box;
    width: 380px;
}
.login-popup__header{
    margin: -10px -20px 10px -20px;
    background: #d0d0d0;
    box-sizing: border-box;
    padding: 5px 0px;
    text-align: center;
    font-size: 18px;
}
.login-popup__form-label{
    display: block;
}
.login-popup__form-input{
    box-sizing: border-box;
    height: 35px;
    padding: 5px 10px;
    font-size: 16px;
    width: 100%;
}
.login-popup__form-submit{
    display: block;
    width: 100px;
    height: 35px;
    font-size: 16px;
    margin: 0px auto;
}