:root {
    --background-color: #f0f0f0;
    --text-color: #333;
    --card-bg: #fff;
    --accent-color: #4CAF50;
    --white-color: #fff;
    --shadow-color: rgba(0,0,0,0.1);
}

[data-theme="dark"] {
    --background-color: #1a1a1a;
    --text-color: #f0f0f0;
    --card-bg: #2d2d2d;
    --shadow-color: rgba(0,0,0,0.4);
}

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

.theme-toggle {
    position: fixed;
    top: 1rem;
    right: 1rem;
    padding: 0.5rem 1rem;
    cursor: pointer;
    background-color: var(--card-bg);
    color: var(--text-color);
    border: 1px solid var(--accent-color);
    border-radius: 20px;
    font-weight: bold;
    transition: all 0.3s ease;
}

.theme-toggle:hover {
    background-color: var(--accent-color);
    color: white;
}

.contact-section {
    margin-top: 3rem;
    width: 100%;
    max-width: 500px;
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 1.5rem;
    box-shadow: 0 10px 30px var(--shadow-color);
    transition: all 0.3s ease;
    margin-bottom: 2rem;
}

.contact-section h2 {
    margin-top: 0;
    text-align: center;
    color: var(--text-color);
}

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

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

.form-group label {
    font-weight: bold;
    font-size: 0.9rem;
    color: var(--text-color);
}

.form-group input, 
.form-group textarea {
    padding: 0.8rem;
    border: 1px solid #ccc;
    border-radius: 0.5rem;
    background-color: var(--background-color);
    color: var(--text-color);
    font-family: inherit;
    transition: border-color 0.3s ease;
}

[data-theme="dark"] .form-group input,
[data-theme="dark"] .form-group textarea {
    border-color: #444;
}

.form-group input:focus, 
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-color);
}

.submit-btn {
    padding: 1rem;
    border: none;
    border-radius: 0.5rem;
    background-color: var(--accent-color);
    color: white;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.2s ease;
}

.submit-btn:hover {
    background-color: #45a049;
    transform: translateY(-2px);
}

.comments-section {
    width: 100%;
    max-width: 800px;
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 1.5rem;
    box-shadow: 0 10px 30px var(--shadow-color);
    margin-bottom: 4rem;
    transition: all 0.3s ease;
}

.comments-section h2 {
    margin-top: 0;
    text-align: center;
    color: var(--text-color);
    margin-bottom: 2rem;
}