/* ===========================================================================
   common.css — 지안UAI(GANUAI) 사이트 공통 스타일
   전체 페이지(헤더, 푸터, 리셋, 변수, 애니메이션)에서 공통으로 사용됩니다.
   모든 하위 페이지(about/, business/, technology/, careers/ 등)에서
   반드시 이 파일을 <link>로 포함해야 합니다.
   =========================================================================== */

/* CSS RESET & DESIGN SYSTEM VARIABLES */
:root {
    --primary: #0F172A;     /* 신뢰감을 주는 다크 슬레이트 네이비 */
    --secondary: #1E293B;   /* 서브 네이비 */
    --accent: #0EA5E9;      /* 첨단 인공지능 느낌의 스카이 블루 */
    --accent-glow: #38BDF8; /* 라이트 스카이 블루 */
    --text-dark: #0F172A;
    --text-light: #F8FAFC;
    --text-muted: #94A3B8;
    --bg-light: #F8FAFC;
    --bg-white: #FFFFFF;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --max-width: 1200px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Noto Sans KR', sans-serif;
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

li {
    list-style: none;
}


/* HEADER & GNB NAVIGATION */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

.header-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
    height: 80px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo a {
    display: flex;
    align-items: center;
    font-family: 'Montserrat', sans-serif;
    font-weight: 800;
    font-size: 24px;
    color: var(--text-light);
    letter-spacing: -0.5px;
}

.logo span {
    color: var(--accent);
}

.gnb {
    display: flex;
    height: 100%;
}

.nav-item {
    position: relative;
    display: flex;
    align-items: center;
    height: 100%;
    padding: 0 20px;
}

.nav-link {
    font-size: 16px;
    font-weight: 500;
    color: var(--text-light);
    cursor: pointer;
    transition: var(--transition);
}

.nav-link:hover, .nav-item:hover > .nav-link {
    color: var(--accent-glow);
}

/* 2-depth 하위 디렉토리 연동 드롭다운 */
.dropdown {
    position: absolute;
    top: 80px;
    left: 50%;
    transform: translateX(-50%) translateY(15px);
    background-color: var(--secondary);
    min-width: 220px;
    border-radius: 8px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    border: 1px solid rgba(255, 255, 255, 0.05);
    padding: 10px 0;
}

.nav-item:hover .dropdown {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.dropdown a {
    display: block;
    padding: 12px 20px;
    font-size: 14px;
    color: var(--text-muted);
    font-weight: 400;
    white-space: nowrap;
}

.dropdown a:hover {
    background-color: rgba(14, 165, 233, 0.1);
    color: var(--text-light);
    padding-left: 25px;
}

.mobile-toggle {
    display: none;
    color: var(--text-light);
    font-size: 24px;
    cursor: pointer;
}


/* FOOTER BRANDING CARD */
footer {
    background-color: #0B0F19;
    color: var(--text-light);
    padding: 80px 0 40px;
    border-top: 1px solid rgba(255,255,255,0.05);
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 60px;
}

.footer-logo {
    font-family: 'Montserrat', sans-serif;
    font-weight: 800;
    font-size: 24px;
    margin-bottom: 20px;
}

.footer-logo span {
    color: var(--accent);
}

.footer-desc {
    color: var(--text-muted);
    font-size: 14px;
    margin-bottom: 24px;
    max-width: 450px;
    line-height: 1.7;
}

.footer-contact-info {
    font-size: 13.5px;
    color: var(--text-muted);
    line-height: 1.8;
}

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

.footer-title {
    font-size: 16px;
    font-weight: 700;
    margin-bottom: 24px;
    color: var(--text-light);
    position: relative;
}

.footer-title::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -8px;
    width: 30px;
    height: 2px;
    background-color: var(--accent);
}

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a {
    color: var(--text-muted);
    font-size: 14px;
}

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

.footer-bottom {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 40px 20px 0;
    border-top: 1px solid rgba(255,255,255,0.05);
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
    color: var(--text-muted);
}


/* SCROLL ANIMATIONS KEYFRAMES */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}