.v-center {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 200px;
    border: 3px solid green;
}

html, body {
    width: 100%;
    height: 100%;
    padding: 0;
    margin: 0;
}
.bmi { /*my additional class name -for card*/
    margin-left: 13%;
    margin-right: 13%;
    width: auto;
    margin-bottom: 10%;
}
.bmi-h { /*my additional class name -for card*/
    height: 400px;
}
.form-floating {
    margin-bottom: 5px;
    margin-left: 5px;
}


/* Side notes for calling out things
-------------------------------------------------- */

/* Base styles (regardless of theme) */
.callout {
    margin: 20px 0;
    padding: 15px 10px 15px 15px;
    border-left: 5px solid #eee;
}

.callout h4 {
    margin-top: 0;
}

.callout p:last-child {
    margin-bottom: 0;
}

.callout code,
.callout .highlight {
    background-color: #fff;
}

/* Themes for different contexts */
.callout-danger {
    background-color: #fcf2f2;
    border-color: #d9534f;
}

.callout-warning {
    background-color: #fefbed;
    border-color: #f1e7bc;
}

.callout-success {
    background-color: #eaffdb;
    border-color: #5cb85c;
}

.callout-info {
    background-color: #f0f7fd;
    border-color: #d0e3f0;
}