/* ============================================
   COMMON.CSS - 공통 스타일
   헤더, 푸터, 네비게이션, 모바일 메뉴
   이 파일 하나만 수정하면 모든 페이지에 반영됩니다.
   ============================================ */

/* === CSS Variables === */
:root {
    --bg-primary: #0a0e17;
    --bg-secondary: #141d2f;
    --bg-tertiary: #1a2332;
    --text-primary: #ffffff;
    --text-secondary: #b8c1d1;
    --text-muted: #8892a0;
    --accent-primary: #3d84f7;
    --accent-secondary: #0de8b8;
    --accent-tertiary: #ff6b6b;
    --accent-neural: #9d4edd;
    --accent-health: #00b894;
    --accent-rf: #ff9500;
    --hover-color: #4f92fa;
}

/* === Reset & Base === */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

body {
    background: var(--bg-primary);
    color: var(--text-primary);
    overflow-x: hidden;
    line-height: 1.6;
}

/* === Header === */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(10, 14, 23, 0.85);
    backdrop-filter: blur(10px);
    z-index: 100;
    padding: 1rem 2rem;
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: 700;
    background: linear-gradient(90deg, var(--text-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    white-space: nowrap;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    border-radius: 8px;
    display: grid;
    place-items: center;
    font-weight: 700;
    font-size: 1.2rem;
    color: var(--text-primary);
}

/* === Navigation === */
nav ul {
    display: flex;
    gap: 2rem;
    list-style: none;
}

nav a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    position: relative;
}

nav a:hover, nav a.active {
    color: var(--text-primary);
}

nav a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    transition: width 0.3s ease;
}

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

/* === Mobile Menu Button === */
.mobile-menu-btn {
    display: none;
    cursor: pointer;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.5rem;
    z-index: 250;
}

/* === Main Content === */
main {
    padding-top: 100px;
}

/* === Footer === */
footer {
    background: var(--bg-secondary);
    padding: 3rem 2rem 1.5rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.footer-row {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.footer-row-title {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
    min-width: 120px;
}

.footer-row-links {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.footer-row-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.85rem;
    transition: color 0.3s ease;
}

.footer-row-links a:hover {
    color: var(--accent-primary);
}

.footer-row-links span {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.footer-logo h2 {
    font-size: 1.1rem;
    background: linear-gradient(90deg, var(--text-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.footer-info p {
    color: var(--text-secondary);
    font-size: 0.85rem;
    line-height: 1.6;
    margin-bottom: 1rem;
}

.social-links {
    display: flex;
    gap: 0.5rem;
}

.social-link {
    width: 32px;
    height: 32px;
    background: rgba(61, 132, 247, 0.1);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-primary);
    text-decoration: none;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.social-link:hover {
    background: var(--accent-primary);
    transform: translateY(-2px);
}

.footer-title {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.footer-links {
    list-style: none;
}

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

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.85rem;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: var(--accent-primary);
}

.footer-contact .contact-item {
    display: flex;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
    align-items: flex-start;
}

.footer-contact .contact-item i {
    font-size: 0.9rem;
    width: 16px;
    flex-shrink: 0;
}

.footer-contact .contact-info {
    color: var(--text-secondary);
    font-size: 0.8rem;
    line-height: 1.5;
}

.footer-contact .contact-info a {
    color: var(--text-secondary);
    text-decoration: none;
}

.footer-contact .contact-info a:hover {
    color: var(--accent-primary);
}

.copyright {
    text-align: center;
    padding-top: 1.5rem;
    margin-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-muted);
    font-size: 0.8rem;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 0.75rem;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.3s ease;
}

.footer-links a:hover {
    color: var(--accent-primary);
    padding-left: 5px;
}

.footer-contact .contact-item {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
    align-items: flex-start;
}

.footer-contact .contact-item i {
    font-size: 1.2rem;
    width: 20px;
    flex-shrink: 0;
}

.footer-contact .contact-info {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}

.footer-contact .contact-info strong {
    color: var(--text-primary);
}

.footer-contact .contact-info a {
    color: var(--accent-primary);
    text-decoration: none;
}

.copyright {
    text-align: center;
    padding-top: 2rem;
    margin-top: 3rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* === Common Section Styles === */
.section-container {
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    font-weight: 700;
    text-align: center;
    background: linear-gradient(90deg, var(--text-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-subtitle {
    text-align: center;
    color: var(--text-secondary);
    max-width: 800px;
    margin: 0 auto 3rem;
    font-size: 1.1rem;
    line-height: 1.6;
}

/* === Animated Gradients === */
.animated-gradient {
    position: absolute;
    width: 800px;
    height: 800px;
    border-radius: 50%;
    filter: blur(60px);
    animation: float 15s infinite alternate ease-in-out;
    z-index: 1;
    pointer-events: none;
}

.gradient-1 {
    top: -300px;
    right: -300px;
    background: radial-gradient(circle, rgba(61, 132, 247, 0.2) 0%, rgba(13, 232, 184, 0.1) 50%, rgba(10, 14, 23, 0) 70%);
    animation-delay: 0s;
}

.gradient-2 {
    bottom: -300px;
    left: -300px;
    background: radial-gradient(circle, rgba(13, 232, 184, 0.2) 0%, rgba(61, 132, 247, 0.1) 50%, rgba(10, 14, 23, 0) 70%);
    animation-delay: -5s;
}

@keyframes float {
    0% { transform: translate(-5%, -5%); }
    100% { transform: translate(5%, 5%); }
}

/* === Page Hero === */
.page-hero {
    padding: 4rem 2rem;
    position: relative;
    overflow: hidden;
}

/* === Breadcrumb === */
.breadcrumb {
    display: flex;
    margin-bottom: 2rem;
    align-items: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.breadcrumb a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s ease;
}

.breadcrumb a:hover {
    color: var(--accent-primary);
}

.breadcrumb-separator {
    margin: 0 0.5rem;
}

/* === Buttons === */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    border-radius: 12px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: var(--text-primary);
    box-shadow: 0 4px 20px rgba(61, 132, 247, 0.3);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(61, 132, 247, 0.4);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--accent-primary);
}

.btn-secondary:hover {
    background: rgba(61, 132, 247, 0.1);
    transform: translateY(-3px);
}

/* === Back Button === */
.back-button {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: var(--bg-secondary);
    color: var(--text-primary);
    text-decoration: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.3s ease;
    margin-bottom: 2rem;
}

.back-button:hover {
    background: rgba(61, 132, 247, 0.1);
    transform: translateX(-5px);
}

/* ============================================
   RESPONSIVE - Mobile Menu (100% 작동 보장)
   people.html에서 검증된 방식 그대로 적용
   ============================================ */

@media (max-width: 768px) {
    /* 모바일 메뉴 버튼 표시 */
    .mobile-menu-btn {
        display: block;
    }
    
    /* 네비게이션 - 오른쪽에서 슬라이드 */
    nav {
        position: fixed;
        top: 0;
        right: -300px;
        width: 300px;
        height: 100vh;
        background: var(--bg-secondary);
        padding: 2rem;
        z-index: 200;
        transition: all 0.3s ease;
    }
    
    /* 메뉴 활성화 시 */
    nav.active {
        right: 0;
    }
    
    /* 메뉴 항목 세로 배치 */
    nav ul {
        flex-direction: column;
        margin-top: 3rem;
    }
    
    /* 로고 크기 조정 */
    .logo h1 {
        font-size: 1.2rem;
    }
    
    /* 섹션 타이틀 */
    .section-title {
        font-size: 2rem;
    }
    
    /* Footer */
    .footer-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }
    
    .footer-logo {
        justify-content: center;
    }
    
    .social-links {
        justify-content: center;
    }
    
    .footer-contact .contact-item {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .logo h1 {
        font-size: 1rem;
    }
    
    .logo-icon {
        width: 35px;
        height: 35px;
        font-size: 1rem;
    }
    
    header {
        padding: 0.8rem 1rem;
    }
    
    .section-title {
        font-size: 1.6rem;
    }
}