:root {
    --bg-color: #f8f9fa;
    --container-bg: #ffffff;
    --text-color: #212529;
    --text-muted: #6c757d;
    --primary-color: #007bff;
    --primary-hover: #0056b3;
    --button-text: #ffffff;
    --number-bg: #e9ecef;
    --border-color: #dee2e6;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

body.dark-mode {
    --bg-color: #121212;
    --container-bg: #1e1e1e;
    --text-color: #f8f9fa;
    --text-muted: #adb5bd;
    --primary-color: #375a7f;
    --primary-hover: #2b4764;
    --number-bg: #2c2c2c;
    --border-color: #333333;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

.site-header {
    background-color: var(--container-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    margin-bottom: 2rem;
}

.nav-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem;
    background-color: var(--container-bg);
    border-radius: 12px;
    box-shadow: var(--shadow);
}

h1 {
    font-size: 2.2rem;
    margin-bottom: 0.5rem;
    text-align: center;
}

.subtitle {
    text-align: center;
    color: var(--text-muted);
    margin-bottom: 2rem;
}

.controls {
    text-align: center;
    margin-bottom: 2rem;
}

button {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.2s;
}

.primary-btn {
    background-color: var(--primary-color);
    color: var(--button-text);
}

.primary-btn:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

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

#numbers {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 15px;
    min-height: 60px;
}

.number {
    width: 60px;
    height: 60px;
    background-color: var(--number-bg);
    border: 2px solid var(--primary-color);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    animation: fadeIn 0.4s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: scale(0.8); }
    to { opacity: 1; transform: scale(1); }
}

hr {
    border: 0;
    border-top: 1px solid var(--border-color);
    margin: 3rem 0;
}

.content-section h2, .content-section h3 {
    margin: 1.5rem 0 1rem;
}

.content-section ul {
    list-style-position: inside;
    margin-bottom: 1rem;
}

.inquiry-section h2 {
    margin-bottom: 1rem;
    text-align: center;
}

.inquiry-section p {
    text-align: center;
    color: var(--text-muted);
    margin-bottom: 2rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-size: 1rem;
}

.submit-btn {
    width: 100%;
    background-color: var(--primary-color);
    color: var(--button-text);
}

.site-footer {
    text-align: center;
    padding: 3rem 0;
    color: var(--text-muted);
    font-size: 0.9rem;
}

.footer-links {
    margin-top: 1rem;
}

.footer-links a {
    color: var(--primary-color);
    text-decoration: none;
    margin: 0 10px;
}

.footer-links a:hover {
    text-decoration: underline;
}

@media (max-width: 600px) {
    .container {
        padding: 1.5rem;
        margin: 0 1rem;
    }
    
    h1 { font-size: 1.8rem; }
}