:root {
    --bg-color: #f0f2f5;
    --container-bg: #fff;
    --text-color: #333;
    --btn-bg: #4CAF50;
    --btn-hover: #45a049;
    --ball-bg: #f0f0f0;
}

body.dark-mode {
    --bg-color: #1a1a1a;
    --container-bg: #2d2d2d;
    --text-color: #f0f0f0;
    --btn-bg: #2e7d32;
    --btn-hover: #1b5e20;
    --ball-bg: #404040;
}

body {
    font-family: 'Helvetica Neue', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    transition: background-color 0.5s ease, color 0.5s ease;
    padding: 20px 0;
}

.container {
    text-align: center;
    background-color: var(--container-bg);
    padding: 40px;
    border-radius: 16px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
    transition: background-color 0.5s ease;
    position: relative;
    width: 90%;
    max-width: 600px;
}

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

#theme-btn {
    background: none;
    border: 1px solid var(--text-color);
    color: var(--text-color);
    padding: 8px 12px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.3s ease;
}

#theme-btn:hover {
    background-color: rgba(128, 128, 128, 0.1);
}

h1 {
    margin-bottom: 30px;
}

#lotto-container {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-bottom: 30px;
    max-height: 400px;
    overflow-y: auto;
    padding: 10px;
}

.lotto-set {
    padding: 15px;
    border-radius: 12px;
    background-color: rgba(128, 128, 128, 0.05);
}

.lotto-set-label {
    font-weight: bold;
    margin-bottom: 10px;
    font-size: 14px;
    color: var(--text-color);
    opacity: 0.7;
}

.lotto-numbers {
    display: flex;
    justify-content: center;
}

#generate-btn {
    background-color: var(--btn-bg);
    color: white;
    padding: 15px 32px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin: 4px 2px;
    cursor: pointer;
    border-radius: 8px;
    border: none;
    transition: background-color 0.3s;
    width: 100%;
}

#generate-btn:hover {
    background-color: var(--btn-hover);
}

.contact-section {
    margin-top: 50px;
    padding-top: 30px;
    border-top: 1px solid rgba(128, 128, 128, 0.2);
}

.contact-section h2 {
    font-size: 1.5rem;
    margin-bottom: 20px;
    color: var(--text-color);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 15px;
    max-width: 400px;
    margin: 0 auto;
}

.contact-form input,
.contact-form textarea {
    padding: 12px;
    border-radius: 8px;
    border: 1px solid #ccc;
    background-color: var(--container-bg);
    color: var(--text-color);
    font-size: 14px;
    transition: border-color 0.3s;
}

body.dark-mode .contact-form input,
body.dark-mode .contact-form textarea {
    border-color: #444;
}

.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: var(--btn-bg);
}

.contact-form textarea {
    height: 100px;
    resize: none;
}

#submit-btn {
    background-color: var(--text-color);
    color: var(--container-bg);
    padding: 12px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: bold;
    transition: opacity 0.3s;
}

#submit-btn:hover {
    opacity: 0.8;
}

@media (max-width: 600px) {
    .container {
        padding: 20px;
    }

    .lotto-numbers {
        flex-wrap: wrap;
        gap: 10px;
    }
    
    lotto-ball {
        margin: 5px !important;
    }
}