body {
    font-family: 'Roboto', Arial, sans-serif;
    background-color: #F5F5F5;
    margin: 0;
    padding: 0;
}

#wrapper {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background-color: #fff;
    border-radius: 5px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    margin-bottom: 30px;
    color: #fff;
    background-color: #4CAF50;
    padding: 10px 0;
    border-radius: 5px;
}

#users-container {
    display: flex;
    justify-content: space-between;
}

#users-present-container,
#users-absent-container {
    flex-basis: 48%;
}

ul {
    list-style-type: none;
    padding: 0;
}

li {
    background-color: #f9f9f9;
    padding: 10px;
    margin-bottom: 5px;
    border-radius: 5px;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

button {
    cursor: pointer;
    border: none;
    padding: 5px 10px;
    border-radius: 5px;
    font-weight: bold;
}

button.checkin-btn {
    background-color: #4CAF50; /* Green */
    color: white;
    margin-right: 5px;
}

button.checkout-btn {
    background-color: #007BFF; /* Blue */
    color: white;
    margin-right: 5px;
}

button.delete-btn {
    background-color: #FF0000; /* Red */
    color: white;
}

#add-user-form {
    margin-top: 20px;
    text-align: center;
}

#new-user-name {
    padding: 5px;
    width: 60%;
    margin-right: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
}

button[type="submit"] {
    background-color: #007BFF; /* Blue */
    color: white;
    cursor: pointer;
    border: none;
    padding: 5px 10px;
    border-radius: 5px;
    font-weight: bold;
}