html, body {
    margin: 0;
    padding: 0;
    height: 100%;
    overflow: auto;
}

.center {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 20px;
    box-sizing: border-box;
    max-width: 100%;
    max-height: 100%;
    overflow-y: auto;
    text-align: center;
    margin-top: 50px; 
}

mdui-card {
    width: 100%;
    max-width: 600px;
    min-width: 300px;
    padding: 16px;
    margin-bottom: 20px;
    text-align: center;
}

mdui-card>* {
    max-width: 100%;
    overflow-wrap: break-word;
}

html, body {
    height: 100%;
    display: flex;
    flex-direction: column;
    overflow: auto; 
}
html,
body {
    margin: 0;
    padding: 0;
    height: 100%;
    overflow: auto;
}

.center {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 20px;
    box-sizing: border-box;
    max-width: 100%;
    max-height: 100%;
    overflow-y: auto;
    text-align: center;
    margin-top: 50px;
}

mdui-card {
    width: 100%;
    max-width: 600px;
    min-width: 300px;
    padding: 16px;
    margin-bottom: 20px;
    text-align: center;
}

mdui-card > * {
    max-width: 100%;
    overflow-wrap: break-word;
    margin: 5px;
}

html,
body {
    height: 100%;
    display: flex;
    flex-direction: column;
    overflow: auto;
}