/* 기본 스타일 */
body {
    font-family: 'Nanum Square Neo', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    font-weight: 400;
    line-height: 1.6;
    color: #333;
}

/* 제목 스타일 */
h1, h2, h3, h4, h5, h6 {
    font-family: 'Nanum Square Neo', sans-serif;
    font-weight: 700;
}

.display-4 {
    font-weight: 900;
}

.section-title {
    font-weight: 800;
}

.lead {
    font-weight: 300;
}

/* 네비게이션 */
.navbar-brand {
    font-family: 'Nanum Square Neo', sans-serif;
    font-weight: 800;
    font-size: 1.5rem;
}

.navbar-nav .nav-link {
    font-family: 'Nanum Square Neo', sans-serif;
    font-weight: 400;
}

/* 투명 네비게이션 */
#mainNavbar {
    background-color: transparent !important;
    transition: all 0.3s ease-in-out;
    padding-top: 2rem;
    padding-bottom: 2rem;
}

#mainNavbar.scrolled {
    background-color: rgba(33, 37, 41, 0.95) !important;
    padding-top: 2rem;
    padding-bottom: 2rem;
}

/* 네비게이션 링크 스타일 개선 */
.navbar-brand {
    position: absolute;
    left: 50px;
    z-index: 1000;
    font-size: 1.8rem !important;
    font-weight: 900 !important;
}

.navbar-nav {
    align-items: center;
}

.navbar-nav .nav-item {
    margin: 0 1rem;
}

.navbar-nav .nav-link {
    font-weight: 700 !important;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-size: 17px !important;
    padding: 0.8rem 1.2rem !important;
    position: relative;
    transition: all 0.3s ease;
    overflow: hidden;
}

/* 밑줄 애니메이션 */
.navbar-nav .nav-link::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, #667eea, #764ba2);
    transform: translateX(-50%);
    transition: width 0.4s ease;
}

.navbar-nav .nav-link:hover::before {
    width: 80%;
}

.navbar-nav .nav-link:hover {
    color: #fff !important;
    text-shadow: 0 0 15px rgba(255, 255, 255, 0.5);
    transform: translateY(-2px) scale(1.05);
    letter-spacing: 1px;
}

/* 글로우 효과 */
.navbar-nav .nav-link:hover {
    animation: glow 0.3s ease-in-out;
}

@keyframes glow {
    0% {
        text-shadow: 0 0 5px rgba(255, 255, 255, 0.3);
    }
    50% {
        text-shadow: 0 0 20px rgba(255, 255, 255, 0.6), 0 0 30px rgba(102, 126, 234, 0.4);
    }
    100% {
        text-shadow: 0 0 15px rgba(255, 255, 255, 0.5);
    }
}

/* 버튼 스타일 */
.btn {
    font-family: 'Nanum Square Neo', sans-serif;
    font-weight: 700;
}

/* 카드 제목 */
.content-card h5 {
    font-weight: 700;
}

/* 푸터 */
footer h5, footer h6 {
    font-weight: 700;
}

/* 애니메이션 */
.content-card {
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.content-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.15);
}

/* 반응형 */
@media (max-width: 768px) {
    .hero-section {
        padding: 80px 0 40px;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .feature-icon {
        font-size: 2rem;
    }
}