body {
    color: #333;
    font-family: 'Arial', sans-serif;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.header, .footer {
    background-color: rgb(245, 245, 245); /* Light grey color */
    text-align: center;
    padding: 10px 0;
    position: fixed;
    width: 100%;
    z-index: 1000;
    height: 30px;
}

.header {
    top: 0;
}

header h1 {
    margin: 0;
    font-weight: lighter;
    font-size: larger;
}

.footer {
    color: #999;
    bottom: 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer > * {
    display: flex;
    align-items: center;
    justify-content: space-around;
}

.footer div:first-child {
    flex: 1;
    justify-content: space-around;
}

.footer div:last-child{
    justify-content: flex-end;
}

.footer .user {
    padding: 0 20px;
}

.footer a {
    color: inherit;
    text-decoration: none;
}

.footer a.active {
    color: #007BFF; /* Bootstrap primary blue */
}

.container {
    flex: 1;
    padding-top: 100px; /* Height of the header */
    padding-bottom: 40px; /* Height of the footer */
    text-align: center;
}

.floating-add-button {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 60px;
    height: 60px;
    background-color: #007BFF;
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 24px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    text-align: center;
    line-height: 60px;
    text-decoration: none;
    cursor: pointer;
    transition: background-color 0.3s;
}

.floating-add-button:hover {
    background-color: #0056b3;
}

.add-user form {
    display: flex;
    flex-direction: column;
    max-width: 600px;
    margin: 0 auto;
    background-color: #f9f9f9;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    text-align: left;
}

.add-user form label {
    margin-bottom: 10px;
}

.add-user form input[type="text"],
.add-user form input[type="radio"] {
    margin-bottom: 20px;
}

.add-user form input[type="text"] {
    width: 100%;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
    box-sizing: border-box;
}

.add-user form input[type="radio"] {
    margin-right: 10px;
}

.add-user .color-dot {
    display: inline-block;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    margin-right: 8px;
}

.add-user form fieldset {
    border: none;
    padding: 0;
    margin-bottom: 20px;
    max-width: 300px;
}

.add-user form legend {
    font-weight: bold;
    margin-bottom: 10px;
}

.add-user form button {
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    background-color: #007BFF;
    color: white;
    font-size: 16px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.add-user form button:hover {
    background-color: #0056b3;
}

.tests {
    margin-top: 20px;
}

.tests ul {
    list-style-type: none;
    padding: 0;
    border-bottom: 1px solid #999;
}

.tests ul li {
    padding: 20px 0;
    border-top: 1px solid #999;
}

.tests ul li a{
    color: inherit;
    text-decoration: none;
}

.user-button {
    display: inline-block;
    margin: 10px;
    text-align: center;
    border: none;
    background-color: #a6aeb6; /* Grey color */
    cursor: pointer;
    padding: 20px 40px; /* More padding for width */
    border-radius: 5px;
    color: white;
    width: 200px; /* Fixed width */
    transition: background-color 0.3s ease;
}

.user-button:hover {
    background-color: #868e96; /* Darker grey for hover effect */
}

.user-button img {
    width: 80px; /* Smaller width */
    height: 80px; /* Smaller height */
    filter: invert(1); 
}

.user-button p {
    margin-top: 10px;
    font-size: 16px;
}


#calendar {
    width: 100%;
    max-width: 600px;
    margin: 0 auto;
}

#calendar table {
    width: 100%;
    border-collapse: collapse;
}

#calendar th, #calendar td {
    border: 1px solid #ddd;
    padding: 10px;
    text-align: center;
}

#calendar th {
    background-color: #f2f2f2;
}

td.highlight {
    background-image: url('img/star.png');
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
}

td.today {
    font-weight: bold;
}

.button-link {
    display: inline-block;
    padding: 10px 20px;
    font-size: 16px;
    color: white;
    background-color: #007BFF; /* Bootstrap primary blue */
    border: none;
    border-radius: 5px;
    text-align: center;
    text-decoration: none;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.button-link:hover {
    background-color: #0056b3; /* Darker blue for hover effect */
}

.activities a.button-link {
    margin-top: 20px;
}

.test_1x1 .test {
    width: 100%;
    max-width: 600px;
    margin: 0 auto;
}


.test_1x1 #problem {
    font-size: 24px;
    margin-bottom: 20px;
}

.test_1x1 #answer {
    font-size: 24px;
    margin-bottom: 20px;
    min-height: 24px;
    display: flex;
    justify-content: center;
    gap: 10px;
}

.test_1x1 .digit {
	background-color: rgb(245, 245, 245);
	width: 20px;
	height: 40px;
	border-bottom: 1px solid #ccc;
}

.test_1x1 .digit span {
    line-height: 40px;
}

.test_1x1 #buttons {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 10px;
}

.test_1x1 button {
    font-size: 18px;
    padding: 10px;
    cursor: pointer;
    background-color: #3498db;
    color: #fff;
    border: none;
    border-radius: 5px;
}

.test_1x1 button:hover {
    background-color: #2980b9;
}

.hidden {
    display: none;
}

.matrix-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 20px auto;
    padding: 10px;
}

.matrix-row {
    display: flex;
}

.matrix-cell {
    width: 40px;
    height: 40px;
    display: flex;
    justify-content: center;
    align-items: center;
    border: 1px solid #ddd;
    margin: 2px;
    font-size: 14px;
    font-weight: bold;
    color: #333;
    text-align: center;
    background-color: lightgray; /* Default background color */
}

.matrix-cell:hover {
    border-color: #000;
}

.test_subtraction .test {
    width: 100%;
    max-width: 600px;
    margin: 0 auto;
}

.subtraction-layout {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 40px auto;
    font-size: 32px;
    font-family: monospace;
}

.number-row {
    display: flex;
    gap: 5px;
}

.operator {
    width: 40px;
    height: 60px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 32px;
}

.number-cell {
    width: 50px;
    height: 60px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
}

.carry-row {
    display: flex;
    gap: 5px;
    margin-top: 5px;
}

.carry-cell {
    width: 50px;
    height: 30px;
    display: flex;
    justify-content: center;
    align-items: center;
    color: #e74c3c;
    font-size: 20px;
}

.line-row {
    display: flex;
    gap: 5px;
    margin: 5px 0;
}

.line {
    width: 165px;
    height: 2px;
    background-color: #333;
}

.answer-row {
    display: flex;
    gap: 5px;
}

.answer-cell {
    width: 50px;
    height: 60px;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: rgb(245, 245, 245);
    border-bottom: 2px solid #333;
    font-weight: bold;
}

.test_subtraction #buttons {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 10px;
    margin-top: 40px;
}

.test_subtraction button {
    font-size: 18px;
    padding: 10px;
    cursor: pointer;
    background-color: #3498db;
    color: #fff;
    border: none;
    border-radius: 5px;
}

.test_subtraction button:hover {
    background-color: #2980b9;
}

.test_subtraction #progress {
    margin-bottom: 20px;
    font-size: 16px;
    color: #666;
}

.test_subtraction #progress-bar {
    height: 5px;
    background-color: #2ecc71;
    transition: width 0.3s ease;
}