/* ==========================================================================
   Common Styles — 모든 페이지 공통 (리셋, 변수, 타이포, 버튼, 네비, 푸터 등)
   ========================================================================== */

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #4A90E2;
    --secondary-color: #046bd2;
    --accent-color: #0d5aa7;
    --text-dark: #2C3E50;
    --text-light: #7F8C8D;
    --bg-light: #F5F7FA;
    --white: #FFFFFF;
    --success: #27AE60;
    --danger: #E74C3C;
    --gradient-primary: linear-gradient(135deg, #046bd2 0%, #0d5aa7 100%);
    --gradient-secondary: linear-gradient(135deg, #4A90E2 0%, #357ABD 100%);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.12);
    --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.15);
    --transition: all 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Noto Sans KR', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background: var(--white);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 1rem;
    color: var(--text-dark);
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 80px;
    height: 4px;
    background: var(--gradient-primary);
    margin: 1rem auto 0;
    border-radius: 2px;
}

.section-subtitle {
    text-align: center;
    color: var(--text-light);
    font-size: 1.1rem;
    margin-bottom: 3rem;
}

.gradient-text {
    background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 0 30px rgba(255, 215, 0, 0.3);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 50px;
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
    font-size: 1rem;
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--white);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: var(--white);
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-secondary:hover {
    background: var(--primary-color);
    color: var(--white);
}

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border-color: var(--primary-color);
    padding: 8px 20px;
    font-size: 0.9rem;
}

.btn-outline:hover {
    background: var(--primary-color);
    color: var(--white);
}

.btn-block {
    display: block;
    width: 100%;
}

/* Navigation */
#navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: var(--transition);
}

#navbar.scrolled {
    box-shadow: var(--shadow-md);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
}

.logo img {
    border-radius: 8px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    color: var(--text-dark);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.nav-link.cta-button {
    background: var(--gradient-primary);
    color: var(--white);
    padding: 8px 20px;
    border-radius: 50px;
}

.nav-link.cta-button::after {
    display: none;
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-dark);
}

/* Page Hero Banner (서브 페이지용) */
.page-hero {
    background: var(--gradient-primary);
    padding: 120px 0 60px;
    text-align: center;
    color: var(--white);
    position: relative;
    overflow: hidden;
}

.page-hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.page-hero p {
    font-size: 1.2rem;
    opacity: 0.9;
}

.page-hero-bg {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background-size: cover;
    background-position: center;
    opacity: 0.2;
}

/* Footer */
.footer {
    background: var(--text-dark);
    color: var(--white);
    padding: 3rem 0 1.5rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.7);
    transition: var(--transition);
}

.footer-section a:hover {
    color: var(--white);
}

.footer-section i {
    margin-right: 0.5rem;
    color: var(--primary-color);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.social-links a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

/* Scroll to Top Button */
.scroll-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    color: var(--white);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    z-index: 999;
}

.scroll-top:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.scroll-top.visible {
    display: flex;
}

/* CTA Banner */
.cta-banner {
    background: var(--gradient-primary);
    padding: 60px 0;
    text-align: center;
    color: var(--white);
}

.cta-banner h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.cta-banner p {
    font-size: 1.1rem;
    opacity: 0.9;
    margin-bottom: 2rem;
}

.cta-banner .btn {
    background: var(--white);
    color: var(--secondary-color);
    font-weight: 700;
}

.cta-banner .btn:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

/* Stats Banner */
.stats-banner {
    padding: 60px 0;
    background: var(--bg-light);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    text-align: center;
}

.stats-grid .stat-item {
    padding: 2rem;
    background: var(--white);
    border-radius: 15px;
    box-shadow: var(--shadow-sm);
}

.stats-grid .stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stats-grid .stat-label {
    color: var(--text-light);
    margin-top: 0.5rem;
}

/* Animations */
.fade-in {
    animation: fadeIn 0.6s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Accessibility */
:focus {
    outline: 3px solid var(--primary-color);
    outline-offset: 2px;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* Responsive - Common */
@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: block;
    }

    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        flex-direction: column;
        background: var(--white);
        width: 100%;
        padding: 2rem;
        box-shadow: var(--shadow-md);
        transition: var(--transition);
        align-items: flex-start;
        gap: 1rem;
    }

    .nav-menu.active {
        left: 0;
    }

    .section-title {
        font-size: 2rem;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }

    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }

    .page-hero h1 {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .btn {
        width: 100%;
    }
}

/* Print Styles */
@media print {
    #navbar, .scroll-top, .cta-banner {
        display: none;
    }
}