@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@400;700&display=swap');

* {
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif;
}

body {
    background-color: #f6f6f6;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background-image: linear-gradient(120deg, #89f7fe 0%, #66a6ff 100%);
}

#container {
    text-align: center;
    background: white;
    padding: 40px;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

h1 {
    font-size: 2.5rem;
    color: #333;
    margin-bottom: 20px;
}

table {
    border-collapse: collapse;
    font-size: 1.5rem;
    margin: 0 auto;
}

colgroup, tbody {
    border: solid 2.4px #333;
}

td {
    border: solid 1px #bbb;
    height: 2em;
    width: 2em;
    text-align: center;
    padding: 0;
    font-size: 1.2rem;
}

.btns {
    display: flex;
    justify-content: center;
    margin-top: 20px;
}

button {
    font-size: 1.2rem;
    background-color: #5c6bc0;
    color: white;
    border: none;
    border-radius: 5px;
    padding: 10px 20px;
    margin: 0 10px;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #3f51b5;
}

@media screen and (max-width: 600px) {
    h1 {
        font-size: 2rem;
    }

    table {
        font-size: 1.2rem;
    }

    td {
        height: 1.5em;
        width: 1.5em;
    }

    button {
        font-size: 1rem;
        padding: 8px 16px;
    }
}