body {
    font-family: Arial, sans-serif;
    text-align: center;
    margin: 20px;
    background-color: #333;
    color: white;
}

h1 {
    color: #55acee;
}

label {
    display: block;
    margin-top: 10px;
}

input {
    padding: 5px;
    margin-top: 5px;
    background-color: #444;
    color: white;
    border: 1px solid #888;
}

button {
    padding: 8px 16px;
    margin-top: 10px;
    background-color: #55acee;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

button:hover {
    background-color: #3c8dc5;
}

#result {
    margin-top: 20px;
    color: white;
}

.button-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-gap: 10px;
    margin-top: 20px;
    margin-left: 10%;
    margin-right: 10%;
}

.button-grid button {
    width: 100%;
}

.history-container {
    color: white;
    margin-top: 20px;
}

button#clearHistoryButton {
    padding: 8px 16px;
    margin-top: 10px;
    background-color: #e74c3c;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

button#clearHistoryButton:hover {
    background-color: #c0392b;
}

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
}

.modal-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: #333;
    color: white;
    padding: 30px;
    border-radius: 5px;
    max-height: 70%;
    max-width: 70%;
    overflow-y: auto;
}

.close {
    position: absolute;
    top: 20px;
    right: 20px;
    color: #55acee;
    font-size: 50px;
    font-weight: bold;
    cursor: pointer;
}

.close:hover {
    color: #3c8dc5;
}