body {
    background-color: dimgray;
    font-family: "Open Sans", sans-serif;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    margin: 0;
}

.container {
    display: block;
    background-color: white;
    border-radius: 5px;
    box-shadow: 0 2px 10px black;
    width:400px;
    padding-left: 10px;
    padding-right: 10px;
    align-items: center;
    justify-content: center;
    min-width: 300px;
}

.btn {
    width: 100%;
    cursor: pointer;
    background-color: #3498db;
    border: 2px solid #3498db;
    border-radius: 4px;
    color: #fff;
    display: block;
    font-size: 20px;
    padding: 10px;
    margin-bottom: 10px;
    margin-top: 10px;
}