:root {
    --bg-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --glass-bg: rgba(255, 255, 255, 0.1);
    --glass-border: rgba(255, 255, 255, 0.2);
    --text-color: #ffffff;
    --card-bg: rgba(255, 255, 255, 0.95);
    --accent-color: #6e8efb;
    --secondary-accent: #a777e3;
    --shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
    --transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

[data-theme="dark"] {
    --bg-gradient: linear-gradient(135deg, #0f0c29 0%, #302b63 50%, #24243e 100%);
    --card-bg: rgba(30, 30, 30, 0.95);
    --text-color: #f8f9fa;
    --glass-bg: rgba(0, 0, 0, 0.3);
}

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

body {
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: var(--bg-gradient);
    background-attachment: fixed;
    color: var(--text-color);
    transition: background 0.5s ease;
    padding: 2rem 0;
}

.container {
    text-align: center;
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 4rem 3rem;
    border-radius: 30px;
    border: 1px solid var(--glass-border);
    box-shadow: var(--shadow);
    max-width: 450px;
    width: 90%;
    transition: var(--transition);
    color: #333;
}

[data-theme="dark"] .container { color: #f8f9fa; }

h1 {
    margin-bottom: 0.5rem;
    font-size: 2.2rem;
    font-weight: 800;
    background: linear-gradient(to right, var(--accent-color), var(--secondary-accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    font-size: 0.9rem;
    color: #666;
    margin-bottom: 2.5rem;
    font-weight: 500;
}

[data-theme="dark"] .subtitle { color: #aaa; }

.lotto-numbers {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin: 2.5rem 0;
    perspective: 1000px;
}

.lotto-number {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    color: white;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.2rem;
    font-weight: 800;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2), inset -4px -4px 8px rgba(0,0,0,0.2), inset 4px 4px 8px rgba(255,255,255,0.3);
    text-shadow: 1px 1px 2px rgba(0,0,0,0.3);
}

#generate-btn {
    width: 100%;
    padding: 16px;
    font-size: 1.2rem;
    border: none;
    border-radius: 18px;
    background: linear-gradient(45deg, var(--accent-color), var(--secondary-accent));
    color: white;
    cursor: pointer;
    font-weight: 700;
    transition: var(--transition);
    box-shadow: 0 10px 20px rgba(110, 142, 251, 0.3);
    margin-bottom: 3rem;
}

#generate-btn:hover { transform: translateY(-5px); box-shadow: 0 15px 30px rgba(110, 142, 251, 0.4); }

/* 제휴 문의 스타일 */
.contact-section {
    border-top: 1px solid rgba(0, 0, 0, 0.05);
    padding-top: 2rem;
    text-align: left;
}

[data-theme="dark"] .contact-section { border-top-color: rgba(255, 255, 255, 0.1); }

.contact-title {
    font-size: 1.1rem;
    margin-bottom: 1.2rem;
    font-weight: 700;
    text-align: center;
    color: var(--accent-color);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.form-group input, .form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border-radius: 12px;
    border: 1px solid #ddd;
    background-color: #f9f9f9;
    font-family: inherit;
    font-size: 0.95rem;
    transition: var(--transition);
}

[data-theme="dark"] .form-group input, [data-theme="dark"] .form-group textarea {
    background-color: #2a2a2a;
    border-color: #444;
    color: #eee;
}

.form-group input:focus, .form-group textarea:focus {
    outline: none;
    border-color: var(--accent-color);
    background-color: #fff;
    box-shadow: 0 0 0 4px rgba(110, 142, 251, 0.1);
}

[data-theme="dark"] .form-group input:focus, [data-theme="dark"] .form-group textarea:focus {
    background-color: #333;
}

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

.submit-btn {
    padding: 12px;
    border: 1px solid var(--accent-color);
    background: transparent;
    color: var(--accent-color);
    border-radius: 12px;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
}

.submit-btn:hover {
    background: var(--accent-color);
    color: white;
}

.theme-toggle {
    position: fixed;
    top: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--glass-bg);
    backdrop-filter: blur(5px);
    border: 1px solid var(--glass-border);
    font-size: 1.5rem;
    cursor: pointer;
    border-radius: 15px;
    color: white;
    z-index: 100;
}