main.css

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 25px;
    padding: 30px;
    line-height: 1.6;
}

small {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 15px;
    padding: 20px;
    line-height: 1.1;
}

very-small {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 10px;
    padding: 2px;
    line-height: 0.9;
}

h1 {
    text-align: center;
    margin-bottom: 30px;
    border-bottom: 1px #ccc solid;
}

h2 {
    margin-top: 20px;
}

.grey-input {
    background-color: #e7e7e7; 
    color: black; /* Gray */
    margin: 1px 0;
    padding: 1px 1px;
    width: 550px;   
    display: flexbox;
    font-size: 15px;
} 

.white-input[type="text"] {
    border: 1px #ccc solid;
    width: 300px;
    padding: 4px;
    height: 35px;
    margin-top: 10px;
    opacity: 0.9;
}

.policy {
    background-color: #e7e7e7; 
    color: black; /* Gray */
    margin: 1px 0;
    padding: 1px 1px;
    width: 550px;   
    display: block;
} 

button {
    cursor: pointer;
    display: inline-block;
    background-color: #24a0ed; 
    border: 0;
    border-radius: 5px;
    padding: 10px 20px;
    margin: 20px 0;
}

.green-button {
    cursor: pointer;
    display: inline-block;
    background-color: #4CAF50; /* Green */
    border: 0;
    border-radius: 5px;
    padding: 10px 20px;
    margin: 20px 0;
}

.red-button {
    cursor: pointer;
    display: inline-block;
    background-color: #D01010; /* RED */
    border: 0;
    border-radius: 5px;
    padding: 10px 20px;
    margin: 20px 0;
}     

.white-button {
    cursor: pointer;
    display: inline-block;
    background-color: #FFFFFF; /* White */
    border: 2px solid #00AF50;
    border-radius: 5px;
    padding: 2px 4px;
    margin: 2px;
    border-color: #FF0000;
    color: black;
}   

input[type="text"] {
    border: 1px #ccc solid;
    width: 350px;
    padding: 4px;
    height: 35px;
    margin-top: 10px;
    opacity: 0.9;
}

#overlay {
    display: none;
    position: absolute;
    width: 100px;
    height: 100px;
    background-color: gray;
    top: 50px;
    left: 50px;
    padding: 10px;
    opacity: .8;
}

.card {
    margin: 20px 0;
    border: #ccc 1px solid;
    padding: 20px;
}

.box {
    background: steelblue;
    width: 1.6em;
    height: 1.6em;
}

.switch-toggle {
    float: left;
    background: #242729;
}

.switch-toggle input {
    position: absolute;
    opacity: 0;
}

.switch-toggle input + label {
    padding: 7px;
    float:left;
    color: #fff;
    cursor: pointer;
    }
    .switch-toggle input:checked + label {
    background: blue;
}

.highlighted {
    background-color: #ff0;
}

/* Tooltip container */
.tooltip {
    position: relative;
    display: inline-block;
    border: 1px black; /* If you want dots under the hoverable text */
    /*border-top: 2px solid #000;*/
}

.visible {
    display: block;
}

.hidden {
    display: none;
}

/* Tooltip text */
.tooltip .tooltiptext {
    visibility: hidden;
    width: 320px;
    background-color: #FFFFA0; 
    color: #000000;
    text-align: center;
    padding: 10px 0;
    border-radius: 6px solid #000;

    /* Position the tooltip text */
    position: absolute;
    z-index: 1;
    bottom: 10%;
    left: 50%;
    margin-left: 75px;
    margin-bottom: -560px;

    /* Fade in tooltip */
    opacity: 0;
    transition: opacity 0.3s;
}

/* Tooltip arrow */
.tooltip .tooltiptext::after {
    content: "";
    position: absolute;
    top: 200%;
    left: 250%;
    margin-left: -5px;
    border-width: 5px;
    border-style: solid;
    border-color: #555 transparent transparent transparent;
}

/* Show the tooltip text when you mouse over the tooltip container */
.tooltip:hover .tooltiptext {
    visibility: visible;
    opacity: 1;
}

.show-btn {
    display: inline-block;
}

.hide-btn {
    display: none;
}

.display-error {
    color: #D01010;
    font-size: small;
}