/* -----------------------------------------------------
   RESET & BASE
----------------------------------------------------- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Pretendard', 'Inter', sans-serif;
}

html, body {
    width: 100%;
    min-height: 100%;
    background: #000;
    color: #fff;
    overflow-x: hidden;
    padding-top: 80px; 
}

/* -----------------------------------------------------
   BACKGROUND & OVERLAY
----------------------------------------------------- */
.bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    /* 경로 수정 및 index 배경 기본값 설정 */
    background-image: url("./bg-index.png"); 
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
}

.bg::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.7); 
    z-index: 1;
}

/* -----------------------------------------------------
   PAGE SPECIFIC BACKGROUNDS (페이지별 배경 추가)
----------------------------------------------------- */
body.page-about .bg { background-image: url("./bg-about.png"); }
body.page-contact .bg { background-image: url("./bg-contact.png"); }
body.page-portfolio .bg { background-image: url("./bg-portfolio.png"); }
body.page-services .bg { background-image: url("./bg-services.png"); }


/* -----------------------------------------------------
   NAVIGATION (Neon Glow Logo + Fixed + Responsive)
----------------------------------------------------- */

nav {
    width: 100%;
    padding: 15px 0;
    background: rgba(13,13,15,0);
    border-bottom: 1px solid rgba(255,255,255,0.08);
    position: fixed;
    top: 0;
    left: 0;
    z-index: 999;
    backdrop-filter: blur(6px);
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 40px;
    transition: background 0.5s ease, padding 0.4s ease;
}

body.scrolled nav {
    background: rgba(13,13,15,0.95); 
    padding: 13px 0;
}

nav .logo {
    position: absolute;
    left: 25px;
}

nav .logo img {
    height: 42px;
    animation: neonPulse 2.0s ease-in-out infinite alternate; 
    box-shadow: 0 0 10px rgba(0, 234, 255, 0.4);
}

@keyframes neonPulse {
    0% { 
        filter: drop-shadow(0 0 2px #00eaff); 
        opacity: 0.8;
    }
    50% { 
        filter: drop-shadow(0 0 18px #00eaff); 
        opacity: 1;
    }
    100% { 
        filter: drop-shadow(0 0 6px #00eaff);
        opacity: 0.85;
    }
}

nav ul {
    display: flex;
    list-style: none;
    gap: 30px;
}

nav a {
    font-size: 18px;
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s, text-shadow 0.3s;
}

nav a:hover {
    color: #00d4ff;
    text-shadow: 0 0 8px #00d4ff;
}

/* 모바일 메뉴 토글 버튼 (PC에서 숨김) */
.menu-toggle {
    display: none;
}


/* -----------------------------------------------------
   LAYOUT & CONTAINER (GVCC 스타일 핵심)
----------------------------------------------------- */
.container {
    width: 90%;
    max-width: 1200px; /* 넓은 레이아웃 */
    margin: 0 auto;
    position: relative;
    z-index: 10;
}

/* 각 섹션 분리 강조 */
.section {
    padding: 80px 0; /* 상하 여백 증가 */
    border-bottom: 1px solid rgba(255, 255, 255, 0.05); /* 얇은 경계선 */
}

/* -----------------------------------------------------
   TYPOGRAPHY
----------------------------------------------------- */

.page-title {
    font-size: 48px; /* 메인 타이틀 크기 증가 */
    font-weight: 700;
    text-align: center;
    margin-bottom: 20px;
    color: #00eaff;
    text-shadow: 0 0 10px rgba(0, 234, 255, 0.3);
}

.page-subtitle {
    text-align: center;
    font-size: 20px;
    color: #999;
    margin-bottom: 60px;
    font-weight: 300;
    line-height: 1.6;
}

h2.section-title {
    font-size: 32px;
    font-weight: 600;
    text-align: center;
    color: #fff;
    margin-bottom: 15px;
    /* 서브 페이지에서는 왼쪽 정렬 */
    text-align: left; 
}
.section h2.section-title {
    /* 메인 섹션 제목은 중앙 정렬 */
    text-align: center; 
}


.section-tagline {
    text-align: center;
    font-size: 18px;
    color: #aaa;
    margin-bottom: 40px;
}


/* -----------------------------------------------------
   CARD & ICON STYLES (GVCC 스타일 핵심)
----------------------------------------------------- */

/* Sub Page Card (about, services, portfolio) */
.sub-card {
    background: rgba(19,19,22,0.85); 
    padding: 35px;
    border-radius: 8px;
    border-top: 5px solid #00eaff;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.3);
    margin-bottom: 30px;
}
.sub-card h2 {
    font-size: 26px;
    color: #00eaff;
    margin-bottom: 15px;
}
.sub-card ul {
    margin-top: 10px;
    padding-left: 20px;
    list-style: none; /* 기본 불릿 제거 */
}
.sub-card ul li {
    font-size: 17px;
    color: #ccc;
    line-height: 1.8;
    position: relative;
    padding-left: 20px;
}
.sub-card ul li::before {
    content: "•"; /* 커스텀 불릿 사용 */
    color: #00eaff;
    font-weight: bold;
    display: inline-block; 
    width: 1em;
    margin-left: -1em;
}


/* Main Index Page Grid */
.service-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr); 
    gap: 30px;
    margin-top: 40px;
}

.service-card {
    background: rgba(19,19,22,0.85); 
    padding: 40px 25px;
    border-radius: 8px;
    border-top: 5px solid #00eaff; 
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.3);
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
}

.service-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 30px rgba(0, 214, 255, 0.2); 
}

.card-icon {
    font-size: 48px;
    color: #00eaff;
    margin-bottom: 15px;
}

.service-card h3 {
    font-size: 22px;
    color: #fff;
    margin-bottom: 10px;
    font-weight: 600;
}

.service-card p {
    font-size: 16px;
    color: #ccc;
    line-height: 1.5;
}

/* Call to Action Button */
.cta-button {
    display: inline-block;
    padding: 15px 35px;
    background: linear-gradient(90deg, #00eaff, #00c8ff);
    color: #000;
    font-weight: bold;
    font-size: 18px;
    border-radius: 5px;
    text-decoration: none;
    margin-top: 20px;
    transition: opacity 0.3s;
}
.cta-button:hover {
    opacity: 0.9;
    color: #000 !important;
}

.highlight {
    color: #00eaff;
    font-weight: bold;
}


/* -----------------------------------------------------
   FOOTER (New Style: Separated from background)
----------------------------------------------------- */
.main-footer {
    padding: 30px 0;
    background: rgba(13,13,15,0.9); /* 네비게이션과 유사한 반투명 배경 */
    border-top: 1px solid rgba(255,255,255,0.08); /* 네비게이션과 유사한 경계선 */
    position: relative; 
    z-index: 99;
    backdrop-filter: blur(6px); /* 블러 효과 */
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 2fr 2fr; /* 4열 레이아웃 */
    gap: 30px;
    padding-top: 20px;
    font-size: 15px;
    line-height: 1.6;
}

.footer-col h4 {
    color: #00eaff;
    font-size: 17px;
    font-weight: 600;
    margin-bottom: 15px;
}

.footer-col ul {
    list-style: none;
    padding: 0;
}

.footer-col ul li {
    margin-bottom: 8px;
    color: #ccc;
}

.footer-col a {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-col a:hover {
    color: #00d4ff;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    margin-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    color: #999;
    font-size: 13px;
}

/* -----------------------------------------------------
   MEDIA QUERIES (모바일 최적화)
----------------------------------------------------- */

@media screen and (max-width: 768px) {
    
    html, body {
        padding-top: 60px; 
    }
    
    .section {
        padding: 50px 0;
    }
    
    .page-title {
        font-size: 30px;
    }
    .page-subtitle {
        font-size: 16px;
        margin-bottom: 30px;
    }
    
    h2.section-title {
        font-size: 24px;
        text-align: center; 
    }
    
    .sub-card {
        padding: 20px;
    }
    .sub-card h2 {
        font-size: 22px;
    }
    .sub-card p, .sub-card ul li {
        font-size: 16px;
    }
    
    /* 1열 그리드로 변경 */
    .service-grid {
        grid-template-columns: 1fr;
    }
    
    .service-card {
        padding: 30px 20px;
    }
    
    /* 네비게이션: 햄버거 메뉴 구조로 변경 */
    nav {
        flex-direction: column;
        padding: 10px 0;
        align-items: flex-start;
    }
    nav .logo {
        position: static; 
        padding: 0 20px;
        width: 100%;
        display: flex;
        justify-content: space-between;
        align-items: center;
    }
    nav .logo img {
        height: 38px; 
    }
    nav ul {
        display: none; 
        width: 100%;
        flex-direction: column;
        gap: 0;
        padding-top: 10px;
        border-top: 1px solid rgba(255,255,255,0.08);
        margin-top: 10px;
    }
    nav.nav-open ul {
        display: flex;
    }
    nav a {
        padding: 10px 20px;
    }
    .menu-toggle {
        display: block; 
        color: #00eaff;
        font-size: 28px;
        line-height: 1;
        cursor: pointer;
        padding-right: 20px;
    }
    
    /* 모바일 푸터 레이아웃 */
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 25px;
    }
}