:root {
    --bg-color: #f0f0f0;
    --container-bg: #fff;
    --text-color: #333;
    --button-bg: #4CAF50;
    --button-text: white;
    --history-item-bg: #eee;
    --shadow-color: rgba(0, 0, 0, 0.1);
}

body.dark-mode {
    --bg-color: #121212;
    --container-bg: #1e1e1e;
    --text-color: #e0e0e0;
    --button-bg: #388E3C;
    --button-text: #e0e0e0;
    --history-item-bg: #2c2c2c;
    --shadow-color: rgba(0, 0, 0, 0.5);
}

body {
    font-family: sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    text-align: center;
    padding: 2rem;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 600px;
    margin: 0 auto;
    background-color: var(--container-bg);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 0 20px var(--shadow-color);
    transition: background-color 0.3s, box-shadow 0.3s;
}

h1 {
    color: var(--text-color);
}

#theme-toggle {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: none;
    border: 1px solid var(--text-color);
    color: var(--text-color);
    padding: 0.5rem 1rem;
    border-radius: 5px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: 0.3s;
}

#theme-toggle:hover {
    background-color: var(--text-color);
    color: var(--bg-color);
}

#generator-btn {
    background-color: var(--button-bg);
    color: var(--button-text);
    padding: 1rem 2rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1.2rem;
    margin-bottom: 2rem;
    box-shadow: 0 4px 8px 0 rgba(0,0,0,0.2);
    transition: 0.3s;
}

#generator-btn:hover {
    box-shadow: 0 8px 16px 0 rgba(0,0,0,0.2);
}

#numbers-display {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.history {
    margin-top: 2rem;
}

#history-list {
    list-style: none;
    padding: 0;
}

#history-list li {
    background-color: var(--history-item-bg);
    padding: 1rem;
    margin-bottom: 1rem;
    border-radius: 5px;
    transition: background-color 0.3s;
}

.contact-section {
    margin-top: 3rem;
    border-top: 1px solid var(--history-item-bg);
    padding-top: 2rem;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    text-align: left;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-group label {
    font-weight: bold;
    font-size: 0.9rem;
}

.form-group input, .form-group textarea {
    padding: 0.8rem;
    border: 1px solid var(--history-item-bg);
    border-radius: 5px;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: inherit;
    transition: 0.3s;
}

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

.form-group input:focus, .form-group textarea:focus {
    outline: none;
    border-color: var(--button-bg);
    box-shadow: 0 0 5px var(--button-bg);
}

#submit-btn {
    background-color: var(--button-bg);
    color: var(--button-text);
    padding: 1rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: bold;
    transition: 0.3s;
}

#submit-btn:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

#disqus_thread {
    margin-top: 3rem;
    border-top: 1px solid var(--history-item-bg);
    padding-top: 2rem;
}