:root {
    --bg-color: #f0f0f0;
    --container-bg: transparent;
    --text-color: #333;
    --btn-bg: #fff;
    --btn-text: #333;
    --number-bg: #fff;
    --number-border: #ccc;
}

body.dark-mode {
    --bg-color: #1a1a1a;
    --container-bg: #2d2d2d;
    --text-color: #f0f0f0;
    --btn-bg: #444;
    --btn-text: #fff;
    --number-bg: #444;
    --number-border: #666;
}

body {
    font-family: sans-serif;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
    margin: 0;
}

.theme-toggle {
    position: absolute;
    top: 20px;
    right: 20px;
}

.container {
    text-align: center;
    padding: 40px;
    border-radius: 10px;
    background-color: var(--container-bg);
}

#theme-btn, #generate-btn {
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
    background-color: var(--btn-bg);
    color: var(--btn-text);
    border: 1px solid var(--number-border);
    border-radius: 5px;
    transition: all 0.3s;
}

#theme-btn:hover, #generate-btn:hover {
    filter: brightness(0.9);
}

.numbers-container {
    display: flex;
    justify-content: center;
    margin-top: 20px;
    flex-wrap: wrap;
    gap: 10px;
}

.number {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background-color: var(--number-bg);
    font-size: 20px;
    font-weight: bold;
    border: 2px solid var(--number-border);
    transition: all 0.3s;
}

.form-container {
    margin-top: 50px;
    padding-top: 30px;
    border-top: 1px solid var(--number-border);
    text-align: left;
    max-width: 400px;
    margin-left: auto;
    margin-right: auto;
}

.form-container h2 {
    text-align: center;
    margin-bottom: 20px;
}

.input-group {
    margin-bottom: 15px;
}

.input-group label {
    display: block;
    margin-bottom: 5px;
    font-size: 14px;
}

.input-group input, .input-group textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--number-border);
    border-radius: 5px;
    background-color: var(--btn-bg);
    color: var(--text-color);
    box-sizing: border-box;
}

.input-group textarea {
    height: 100px;
    resize: vertical;
}

#submit-btn {
    width: 100%;
    margin-top: 10px;
}