/* FRTech 웹사이트 - 미래적 산업 디자인 2025 */

:root {
    /* 메인 컬러 - 산업적 블루/그레이 */
    --primary-color: #0ea5e9;
    --primary-dark: #0284c7;
    --primary-light: #38bdf8;
    --secondary-color: #1e293b;
    --accent-color: #06b6d4;
    --accent-glow: #22d3ee;
    
    /* 텍스트 */
    --text-color: #0f172a;
    --text-light: #64748b;
    --text-muted: #94a3b8;
    
    /* 배경 */
    --bg-color: #ffffff;
    --bg-dark: #0f172a;
    --bg-section: #f8fafc;
    --bg-card: #ffffff;
    --bg-overlay: rgba(15, 23, 42, 0.85);
    
    /* 그라데이션 */
    --gradient-primary: linear-gradient(135deg, #0ea5e9 0%, #06b6d4 100%);
    --gradient-dark: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
    --gradient-overlay: linear-gradient(180deg, rgba(15, 23, 42, 0.7) 0%, rgba(15, 23, 42, 0.9) 100%);
    
    /* 보더 & 그림자 */
    --border-color: #e2e8f0;
    --border-light: #f1f5f9;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 8px 16px -4px rgba(0, 0, 0, 0.12);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.15);
    --shadow-glow: 0 0 20px rgba(14, 165, 233, 0.3);
    
    /* 트랜지션 */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    
    /* 레이아웃 */
    --header-height: 77px;
    --section-padding: 120px;
    --container-max: 1280px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    -ms-text-size-adjust: 100%;
}

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', sans-serif;
    color: var(--text-color);
    line-height: 1.7;
    overflow-x: hidden;
    background: var(--bg-color);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body.menu-open {
    overflow: hidden;
    position: fixed;
    width: 100%;
}

.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 24px;
}

.section {
    padding: var(--section-padding) 0;
    position: relative;
}

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 700;
    text-align: center;
    margin-bottom: 70px;
    color: var(--text-color);
    position: relative;
    letter-spacing: -0.02em;
}

.section-title::before {
    content: '';
    position: absolute;
    top: -20px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--gradient-primary);
    border-radius: 2px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -20px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--primary-color), transparent);
}

.section-title-simple {
    font-size: clamp(1.8rem, 4vw, 2.2rem);
    font-weight: 700;
    text-align: center;
    margin-bottom: 50px;
    color: var(--text-color);
    letter-spacing: -0.01em;
}

/* 헤더 & 네비게이션 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 1);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-light);
    z-index: 1000;
    transition: var(--transition);
}

.header.scrolled {
    box-shadow: var(--shadow-md);
    background: rgba(255, 255, 255, 0.95);
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 24px;
    max-width: var(--container-max);
    margin: 0 auto;
    gap: 20px;
    flex-wrap: nowrap;
}

@media (max-width: 1024px) {
    .nav {
        padding: 12px 20px;
        gap: 16px;
    }
}

@media (max-width: 768px) {
    .nav {
        padding: 11px 20px;
        gap: 12px;
    }
}

.nav-logo {
    flex-shrink: 0;
}

.nav-logo img {
    height: 57px;
    width: auto;
    object-fit: contain;
    transition: var(--transition);
}

.nav-logo:hover img {
    transform: scale(1.05);
}

@media (max-width: 1200px) {
    .nav-logo img {
        height: 53px;
    }
}

@media (max-width: 1024px) {
    .nav-logo img {
        height: 50px;
    }
}

@media (max-width: 768px) {
    .nav-logo img {
        height: 46px;
    }
}

.nav-list {
    display: flex;
    list-style: none;
    gap: 26px;
    align-items: center;
}

@media (max-width: 1200px) {
    .nav-list {
        gap: 22px;
    }
}

@media (max-width: 1024px) {
    .nav-list {
        gap: 18px;
    }
}

.nav-menu {
    flex-grow: 1;
    display: flex;
    justify-content: center;
}

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    font-size: 0.9rem;
    letter-spacing: 0.02em;
    transition: var(--transition);
    position: relative;
    padding: 7px 0;
}

@media (max-width: 1200px) {
    .nav-link {
        font-size: 0.85rem;
    }
}

@media (max-width: 1024px) {
    .nav-link {
        font-size: 0.8rem;
    }
}

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

.nav-link:hover {
    color: var(--primary-color);
}

.nav-link:hover::before {
    width: 100%;
}

/* 언어 전환 버튼 */
.language-switcher {
    display: flex;
    gap: 5px;
    align-items: center;
    padding: 5px;
    background: var(--bg-section);
    border-radius: 25px;
    border: 1px solid var(--border-color);
    flex-shrink: 0;
}

.mobile-lang {
    display: none;
}

.desktop-lang {
    display: flex;
}

.lang-btn {
    padding: 7px 13px;
    border: none;
    background: transparent;
    color: var(--text-light);
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: 20px;
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
    white-space: nowrap;
}

.lang-btn:hover {
    color: var(--primary-color);
    background: rgba(14, 165, 233, 0.1);
}

.lang-btn.active {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 4px 12px rgba(14, 165, 233, 0.3);
}

@media (max-width: 1200px) {
    .lang-btn {
        padding: 6px 11px;
        font-size: 0.75rem;
    }
}

@media (max-width: 1024px) {
    .language-switcher {
        padding: 4px;
        gap: 3px;
    }
    
    .lang-btn {
        padding: 5px 9px;
        font-size: 0.7rem;
    }
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 6px;
    cursor: pointer;
    padding: 12px;
    min-width: 44px;
    min-height: 44px;
    justify-content: center;
    align-items: center;
    border-radius: 4px;
    transition: var(--transition);
}

.nav-toggle:hover {
    background: var(--bg-section);
}

.nav-toggle:active {
    background: var(--border-color);
}

.nav-toggle span {
    width: 24px;
    height: 2.5px;
    background: var(--text-color);
    border-radius: 2px;
    transition: var(--transition);
}

/* 히어로 섹션 - PPT 표지 스타일 */
.hero {
    margin-top: var(--header-height);
    position: relative;
    height: calc(100vh - var(--header-height));
    min-height: 600px;
    overflow: hidden;
    display: flex;
    align-items: center;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
}

.hero-background::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(15, 23, 42, 0.6) 0%, rgba(30, 41, 59, 0.5) 100%);
    z-index: 1;
}

.hero-media {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: brightness(0.85) contrast(1.05);
    opacity: 0;
    transition: opacity 2s ease-in-out;
}

.hero-media.active {
    opacity: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    width: 100%;
    color: white;
}

.hero-text {
    max-width: 800px;
    text-align: left;
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 1s ease-out, transform 1s ease-out;
}

.hero-title {
    font-size: clamp(3rem, 7vw, 5.5rem);
    font-weight: 900;
    margin-bottom: 30px;
    letter-spacing: -0.04em;
    line-height: 1.1;
    color: white;
}

.hero-divider {
    width: 100px;
    height: 5px;
    background: var(--gradient-primary);
    margin-bottom: 30px;
}

.hero-description {
    font-size: clamp(1rem, 2vw, 1.3rem);
    font-weight: 500;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--accent-glow);
    margin-bottom: 16px;
    opacity: 0.9;
}

.hero-subtitle {
    font-size: clamp(1.1rem, 2vw, 1.4rem);
    font-weight: 300;
    margin-bottom: 50px;
    color: rgba(255, 255, 255, 0.85);
    line-height: 1.6;
}

.hero-stats {
    display: flex;
    gap: 50px;
    margin-bottom: 50px;
    flex-wrap: wrap;
}

.hero-stat {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.stat-number {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1;
}

.stat-label {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: rgba(255, 255, 255, 0.6);
    font-weight: 500;
}

.hero-btn {
    display: inline-block;
    padding: 18px 48px;
    background: var(--gradient-primary);
    color: white;
    text-decoration: none;
    border-radius: 4px;
    font-weight: 700;
    font-size: 1rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    transition: var(--transition);
    box-shadow: 0 10px 30px rgba(14, 165, 233, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.1);
    position: relative;
    overflow: hidden;
}

.hero-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s;
}

.hero-btn:hover::before {
    left: 100%;
}

.hero-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 40px rgba(14, 165, 233, 0.5), var(--shadow-glow);
}

.hero-btn:active {
    transform: translateY(-1px);
    box-shadow: 0 8px 20px rgba(14, 165, 233, 0.4);
}

@media (hover: none) and (pointer: coarse) {
    .hero-btn:hover {
        transform: none;
    }
    
    .hero-btn:active {
        transform: scale(0.97);
    }
}

/* 회사소개 - 그리드 레이아웃 */
.about {
    background: var(--bg-section);
    position: relative;
}

.about::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 40%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(14, 165, 233, 0.03));
    pointer-events: none;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.about-image {
    position: relative;
}

.about-image::before {
    content: '';
    position: absolute;
    top: -20px;
    left: -20px;
    right: 20px;
    bottom: 20px;
    border: 2px solid var(--primary-color);
    border-radius: 4px;
    z-index: -1;
}

.about-image img {
    width: 100%;
    border-radius: 4px;
    box-shadow: var(--shadow-lg);
    display: block;
}

.about-text h3 {
    font-size: 2.2rem;
    margin-bottom: 24px;
    color: var(--text-color);
    font-weight: 700;
    letter-spacing: -0.02em;
}

.about-text h3::before {
    content: '';
    display: block;
    width: 50px;
    height: 3px;
    background: var(--gradient-primary);
    margin-bottom: 20px;
}

.about-text p {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: 40px;
    line-height: 1.8;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    align-items: stretch;
}

.stat-item {
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    text-align: center;
    padding: 30px 20px;
    min-height: 168px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.stat-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transition: var(--transition);
}

.stat-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary-color);
}

.stat-item:hover::before {
    transform: scaleX(1);
}

.stat-item h4 {
    font-size: 1.8rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 10px;
    font-weight: 800;
    line-height: 1.15;
    overflow-wrap: anywhere;
}

.stat-item p {
    color: var(--text-light);
    font-size: 0.95rem;
    font-weight: 500;
    line-height: 1.5;
    text-transform: none;
    letter-spacing: 0.01em;
    overflow-wrap: anywhere;
    word-break: keep-all;
    margin-top: auto;
}

/* 프로젝트 - 오버레이 이미지 디자인 */
.projects {
    background: var(--bg-dark);
    position: relative;
}

.projects::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(15, 23, 42, 0.95) 0%, rgba(30, 41, 59, 0.9) 100%);
    pointer-events: none;
}

.projects .container {
    position: relative;
    z-index: 1;
}

.projects .section-title-simple {
    color: white;
}

.project-filters {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-bottom: 50px;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 12px 28px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    border-radius: 8px;
    cursor: pointer;
    transition: var(--transition);
    font-weight: 600;
    font-size: 0.9rem;
    color: white;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.filter-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--primary-color);
    transform: translateY(-2px);
}

.filter-btn.active {
    background: var(--gradient-primary);
    border-color: transparent;
    box-shadow: 0 8px 20px rgba(14, 165, 233, 0.4);
}

.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(380px, 1fr));
    gap: 30px;
}

@media (max-width: 768px) {
    .project-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
}

@media (max-width: 480px) {
    .project-grid {
        gap: 20px;
    }
}

.project-card {
    position: relative;
    height: 400px;
    border-radius: 12px;
    overflow: hidden;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    -webkit-touch-callout: none;
}

.project-card:hover {
    transform: translateY(-10px) scale(1.02);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.7);
}

@media (hover: none) and (pointer: coarse) {
    /* 모바일 터치 최적화 */
    .project-card:hover {
        transform: none;
    }
    
    .project-card:active {
        transform: scale(0.98);
        box-shadow: 0 5px 15px rgba(0, 0, 0, 0.4);
    }
}

.project-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.project-image::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
        180deg,
        rgba(0, 0, 0, 0.3) 0%,
        rgba(0, 0, 0, 0.5) 50%,
        rgba(0, 0, 0, 0.9) 100%
    );
    z-index: 1;
    transition: var(--transition);
}

.project-card:hover .project-image::before {
    background: linear-gradient(
        180deg,
        rgba(0, 0, 0, 0.5) 0%,
        rgba(0, 0, 0, 0.7) 50%,
        rgba(14, 165, 233, 0.8) 100%
    );
}

.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-slow);
}

.project-card:hover .project-image img {
    transform: scale(1.1);
}

.project-info {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 30px;
    z-index: 2;
    color: white;
    transform: translateY(0);
    transition: var(--transition);
}

.project-card:hover .project-info {
    transform: translateY(-10px);
}

.project-category {
    display: inline-block;
    padding: 6px 14px;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: white;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 700;
    margin-bottom: 12px;
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.project-info h3 {
    font-size: 1.4rem;
    margin-bottom: 10px;
    color: white;
    font-weight: 800;
    letter-spacing: -0.02em;
    line-height: 1.3;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.project-info p {
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 12px;
    line-height: 1.6;
    font-size: 0.9rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    text-shadow: 0 1px 5px rgba(0, 0, 0, 0.5);
}

.project-date {
    display: inline-flex;
    align-items: center;
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.8);
    font-weight: 500;
    letter-spacing: 0.05em;
}

.project-date::before {
    content: '';
    display: inline-block;
    width: 6px;
    height: 6px;
    background: var(--accent-glow);
    border-radius: 50%;
    margin-right: 10px;
    box-shadow: 0 0 8px var(--accent-glow);
}

/* GFRP 적용 분야 - 전면 개편 */
.applications {
    background: var(--bg-color);
    position: relative;
}

.applications-header {
    text-align: center;
    margin-bottom: 70px;
}

.applications-subtitle {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-top: -30px;
    font-weight: 400;
}

.applications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
}

@media (max-width: 768px) {
    .applications-grid {
        grid-template-columns: 1fr;
        gap: 28px;
    }
}

@media (max-width: 480px) {
    .applications-grid {
        gap: 20px;
    }
}

.application-item {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    padding: 40px;
    position: relative;
    transition: var(--transition);
    overflow: hidden;
}

.application-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 5px;
    height: 0;
    background: var(--gradient-primary);
    transition: var(--transition);
}

.application-item:hover {
    transform: translateY(-8px);
    border-color: var(--primary-color);
    box-shadow: var(--shadow-lg);
}

.application-item:hover::before {
    height: 100%;
}

.application-number {
    position: absolute;
    top: 30px;
    right: 30px;
    font-size: 4rem;
    font-weight: 900;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    opacity: 0.15;
    line-height: 1;
}

.application-content h3 {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--text-color);
    margin-bottom: 16px;
    letter-spacing: -0.02em;
    position: relative;
    z-index: 1;
}

.application-divider {
    width: 50px;
    height: 3px;
    background: var(--gradient-primary);
    margin-bottom: 16px;
}

.application-subtitle {
    font-size: 0.85rem;
    color: var(--primary-color);
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: 24px;
}

.application-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.application-list li {
    padding: 10px 0;
    color: var(--text-light);
    font-size: 0.95rem;
    position: relative;
    padding-left: 24px;
    line-height: 1.6;
}

.application-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 18px;
    width: 6px;
    height: 6px;
    background: var(--primary-color);
    border-radius: 50%;
}

.application-list li:not(:last-child) {
    border-bottom: 1px solid var(--border-light);
}

/* 인증 및 품질관리 */
.certifications {
    background: var(--bg-section);
    position: relative;
    overflow: hidden;
}

.certifications::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(circle at 20% 30%, rgba(14, 165, 233, 0.05) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(6, 182, 212, 0.05) 0%, transparent 50%);
    pointer-events: none;
}

.certifications .container {
    position: relative;
    z-index: 1;
}

.certifications-subtitle {
    text-align: center;
    font-size: 1.15rem;
    color: var(--text-light);
    margin-top: -40px;
    margin-bottom: 50px;
    font-weight: 400;
    line-height: 1.6;
}

.cert-filters {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-bottom: 60px;
    flex-wrap: wrap;
}

.cert-filter-btn {
    padding: 12px 28px;
    border: 2px solid var(--border-color);
    background: var(--bg-card);
    border-radius: 50px;
    cursor: pointer;
    transition: var(--transition);
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--text-color);
    letter-spacing: 0.02em;
    position: relative;
    overflow: hidden;
}

.cert-filter-btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: var(--gradient-primary);
    transform: translate(-50%, -50%);
    transition: width 0.3s ease, height 0.3s ease;
    z-index: -1;
}

.cert-filter-btn:hover::before {
    width: 200%;
    height: 200%;
}

.cert-filter-btn:hover {
    border-color: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(14, 165, 233, 0.25);
}

.cert-filter-btn.active {
    background: var(--gradient-primary);
    border-color: var(--primary-color);
    color: white;
    box-shadow: 0 8px 20px rgba(14, 165, 233, 0.35);
}

.certifications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
    gap: 32px;
}

@media (max-width: 768px) {
    .certifications-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
}

@media (max-width: 480px) {
    .certifications-grid {
        gap: 20px;
    }
}

.cert-card {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: 16px;
    overflow: hidden;
    transition: var(--transition);
    cursor: pointer;
    position: relative;
    box-shadow: var(--shadow-sm);
    -webkit-touch-callout: none;
}

.cert-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 8px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transform-origin: left;
    transition: var(--transition);
}

.cert-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(14, 165, 233, 0.03) 0%, transparent 50%);
    opacity: 0;
    transition: var(--transition);
    pointer-events: none;
}

.cert-card:hover {
    transform: translateY(-10px);
    border-color: var(--primary-color);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.12);
}

.cert-card:hover::before {
    transform: scaleX(1);
}

.cert-card:hover::after {
    opacity: 1;
}

@media (hover: none) and (pointer: coarse) {
    .cert-card:hover {
        transform: none;
    }
    
    .cert-card:active {
        transform: scale(0.98);
        box-shadow: var(--shadow);
    }
}

.cert-header {
    padding: 35px 30px 25px;
    border-bottom: 1px solid var(--border-light);
    background: linear-gradient(180deg, rgba(248, 250, 252, 0.8) 0%, var(--bg-card) 100%);
    position: relative;
}

.cert-icon {
    position: absolute;
    top: 25px;
    right: 25px;
    width: 60px;
    height: 60px;
    background: var(--gradient-primary);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    opacity: 0.15;
    transform: rotate(-10deg);
    box-shadow: 0 8px 16px rgba(14, 165, 233, 0.2);
}

.cert-status {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 7px 16px;
    background: linear-gradient(135deg, #10b981, #059669);
    color: white;
    border-radius: 25px;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-bottom: 18px;
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}

.cert-status::before {
    content: '✓';
    font-size: 0.95rem;
    font-weight: 900;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    background: rgba(255, 255, 255, 0.25);
    border-radius: 50%;
}

.cert-status.expired {
    background: linear-gradient(135deg, #ef4444, #dc2626);
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.3);
}

.cert-status.expired::before {
    content: '✕';
}

.cert-status.renewing {
    background: linear-gradient(135deg, #f59e0b, #f97316);
    box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
}

.cert-status.renewing::before {
    content: '↻';
}

.cert-header h3 {
    font-size: 1.5rem;
    color: var(--text-color);
    font-weight: 700;
    margin-bottom: 14px;
    letter-spacing: -0.02em;
    line-height: 1.35;
    padding-right: 70px;
}

.cert-issuer {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.95rem;
    color: var(--text-light);
    font-weight: 600;
    padding: 10px 14px;
    background: rgba(14, 165, 233, 0.05);
    border-radius: 8px;
    border-left: 3px solid var(--primary-color);
}

.cert-issuer::before {
    content: '🏛️';
    font-size: 1.2rem;
    filter: grayscale(0.3);
}

.cert-body {
    padding: 30px;
}

.cert-description {
    color: var(--text-light);
    line-height: 1.75;
    font-size: 0.95rem;
    margin-bottom: 26px;
}

.cert-meta {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    padding: 24px;
    background: linear-gradient(135deg, rgba(14, 165, 233, 0.04) 0%, rgba(6, 182, 212, 0.04) 100%);
    border-radius: 10px;
    border: 1px solid rgba(14, 165, 233, 0.1);
}

.cert-meta-item {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.cert-meta-label {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--text-muted);
    font-weight: 700;
}

.cert-meta-value {
    font-size: 1rem;
    color: var(--text-color);
    font-weight: 700;
    font-family: 'Courier New', monospace;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.cert-footer {
    padding: 22px 30px;
    background: linear-gradient(135deg, rgba(15, 23, 42, 0.02) 0%, rgba(30, 41, 59, 0.02) 100%);
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid var(--border-light);
}

.cert-category-badge {
    padding: 8px 18px;
    background: linear-gradient(135deg, rgba(14, 165, 233, 0.12) 0%, rgba(6, 182, 212, 0.12) 100%);
    color: var(--primary-color);
    border-radius: 25px;
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    border: 1px solid rgba(14, 165, 233, 0.2);
}

.cert-number {
    font-size: 0.8rem;
    color: var(--text-muted);
    font-weight: 600;
    font-family: 'Courier New', monospace;
    letter-spacing: 0.05em;
}

/* 뉴스 */
.news {
    background: var(--bg-section);
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 32px;
}

@media (max-width: 768px) {
    .news-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
}

@media (max-width: 480px) {
    .news-grid {
        gap: 20px;
    }
}

.news-card {
    background: var(--bg-card);
    border-radius: 4px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-light);
    cursor: pointer;
    -webkit-touch-callout: none;
}

.news-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent-color);
}

@media (hover: none) and (pointer: coarse) {
    .news-card:hover {
        transform: none;
    }
    
    .news-card:active {
        transform: scale(0.98);
        box-shadow: var(--shadow);
    }
}

.news-image {
    width: 100%;
    height: 220px;
    overflow: hidden;
    position: relative;
}

.news-image::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(180deg, transparent, rgba(0, 0, 0, 0.4));
}

.news-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-slow);
}

.news-card:hover .news-image img {
    transform: scale(1.08);
}

.news-content {
    padding: 28px;
}

.news-category {
    display: inline-block;
    padding: 6px 16px;
    background: linear-gradient(135deg, #f59e0b, #f97316);
    color: white;
    border-radius: 2px;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    margin-bottom: 16px;
}

.news-content h3 {
    font-size: 1.4rem;
    margin-bottom: 12px;
    color: var(--text-color);
    font-weight: 700;
    letter-spacing: -0.01em;
    line-height: 1.4;
}

.news-content p {
    color: var(--text-light);
    margin-bottom: 20px;
    line-height: 1.7;
    font-size: 0.95rem;
}

.news-date {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* 더보기 카드 */
.news-card-more {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 400px;
    border: 2px dashed rgba(255, 255, 255, 0.3);
    position: relative;
    overflow: hidden;
}

.news-card-more::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    animation: pulse 3s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); opacity: 0.5; }
    50% { transform: scale(1.2); opacity: 0.8; }
}

.news-card-more:hover {
    transform: translateY(-8px) scale(1.02);
    border-color: rgba(255, 255, 255, 0.6);
}

.news-more-content {
    text-align: center;
    color: white;
    z-index: 1;
    position: relative;
    padding: 40px;
}

.news-more-icon {
    font-size: 5rem;
    font-weight: 300;
    line-height: 1;
    margin-bottom: 20px;
    text-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    transition: var(--transition);
}

.news-card-more:hover .news-more-icon {
    transform: rotate(90deg) scale(1.1);
}

.news-more-content h3 {
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: 10px;
    letter-spacing: -0.02em;
}

.news-more-content p {
    font-size: 1rem;
    font-weight: 400;
    opacity: 0.9;
    letter-spacing: 0.02em;
}

/* 문의 섹션 */
.contact {
    background: var(--bg-color);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 60px;
}

.contact-info {
    background: var(--gradient-dark);
    color: white;
    padding: 50px 40px;
    border-radius: 4px;
    position: relative;
    overflow: hidden;
}

.contact-info::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 200px;
    height: 200px;
    background: radial-gradient(circle, rgba(14, 165, 233, 0.2), transparent);
    border-radius: 50%;
}

.contact-info h3 {
    font-size: 1.8rem;
    margin-bottom: 40px;
    font-weight: 700;
    position: relative;
}

.contact-info h3::after {
    content: '';
    display: block;
    width: 50px;
    height: 3px;
    background: var(--gradient-primary);
    margin-top: 16px;
}

.contact-item {
    margin-bottom: 32px;
    position: relative;
    padding-left: 0;
}

.contact-item strong {
    display: block;
    margin-bottom: 8px;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: rgba(255, 255, 255, 0.7);
}

.contact-item p {
    color: white;
    font-size: 1.1rem;
    font-weight: 500;
}

.contact-form {
    background: var(--bg-card);
    padding: 50px;
    border-radius: 4px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-md);
}

.form-group {
    margin-bottom: 28px;
}

.form-group label {
    display: block;
    margin-bottom: 10px;
    font-weight: 600;
    color: var(--text-color);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 14px 18px;
    border: 2px solid var(--border-color);
    border-radius: 4px;
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
    background: var(--bg-color);
    color: var(--text-color);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.1);
}

.submit-btn {
    width: 100%;
    padding: 16px;
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: 4px;
    font-size: 1.05rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    box-shadow: 0 10px 20px rgba(14, 165, 233, 0.3);
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 30px rgba(14, 165, 233, 0.4);
}

.submit-btn:active {
    transform: translateY(0);
}

@media (hover: none) and (pointer: coarse) {
    .submit-btn:hover {
        transform: none;
    }
    
    .submit-btn:active {
        transform: scale(0.97);
        opacity: 0.9;
    }
}

/* 푸터 */
.footer {
    background: var(--gradient-dark);
    color: white;
    padding: 80px 0 30px;
    position: relative;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-primary);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 60px;
    margin-bottom: 50px;
}

.footer-section h4 {
    font-size: 1.4rem;
    margin-bottom: 24px;
    font-weight: 700;
}

.footer-section h4::after {
    content: '';
    display: block;
    width: 40px;
    height: 2px;
    background: var(--gradient-primary);
    margin-top: 12px;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.8;
    font-size: 0.95rem;
}

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

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

.footer-section ul li a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: var(--transition);
    font-size: 0.95rem;
}

.footer-section ul li a:hover {
    color: white;
    padding-left: 8px;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.9rem;
}

/* 맨 위로 버튼 */
.scroll-top {
    position: fixed;
    bottom: 40px;
    right: 40px;
    width: 56px;
    height: 56px;
    background: var(--gradient-primary);
    color: white;
    border: none;
    border-radius: 4px;
    font-size: 1.5rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 999;
    box-shadow: var(--shadow-lg);
}

.scroll-top.show {
    opacity: 1;
    visibility: visible;
}

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

/* 로딩 */
.loading {
    text-align: center;
    padding: 60px;
    color: var(--text-muted);
    font-size: 1.1rem;
    font-weight: 500;
}

/* 반응형 */
@media (max-width: 1024px) {
    :root {
        --section-padding: 70px;
    }

    .about-content,
    .contact-content {
        grid-template-columns: 1fr;
        gap: 50px;
    }

    .about-image::before {
        display: none;
    }
}

@media (max-width: 768px) {
    :root {
        --section-padding: 50px;
        --header-height: 66px;
    }

    .nav {
        padding: 8px 16px;
        gap: 10px;
    }

    .nav-menu {
        position: fixed;
        top: var(--header-height);
        left: -100%;
        width: 100%;
        height: calc(100vh - var(--header-height));
        background: rgba(255, 255, 255, 0.98);
        backdrop-filter: blur(20px);
        padding: 30px 20px;
        box-shadow: var(--shadow-lg);
        transition: left 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        overflow-y: auto;
        display: flex;
        flex-direction: column;
        z-index: 999;
    }

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

    .nav-list {
        flex-direction: column;
        gap: 0;
        width: 100%;
        margin-bottom: auto;
    }

    .nav-link {
        display: flex;
        align-items: center;
        padding: 16px 0;
        font-size: 1.1rem;
        border-bottom: 1px solid var(--border-light);
        width: 100%;
        height: auto;
        min-height: 52px;
    }

    .nav-link::before {
        display: none;
    }

    .nav-toggle {
        display: flex;
        order: 3;
        flex-shrink: 0;
    }
    
    .desktop-lang {
        display: none !important;
    }
    
    .mobile-lang {
        display: flex;
        margin-top: 20px;
        padding-top: 20px;
        border-top: 2px solid var(--border-light);
        justify-content: center;
        width: 100%;
    }

    .mobile-lang .lang-btn {
        padding: 12px 24px;
        font-size: 0.95rem;
        min-height: 44px;
    }

    .mobile-lang .language-switcher {
        width: 100%;
        max-width: 280px;
        padding: 6px;
    }

    .hero {
        height: 70vh;
        min-height: 500px;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-stats {
        gap: 30px;
    }

    .section-title {
        font-size: 2rem;
        margin-bottom: 50px;
    }

    .about-stats {
        grid-template-columns: 1fr;
    }

    .project-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .project-card {
        height: 350px;
    }
    
    .cert-filters {
        gap: 8px;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        -ms-overflow-style: none;
        padding-bottom: 4px;
    }
    
    .cert-filters::-webkit-scrollbar {
        display: none;
    }
    
    .cert-filter-btn {
        padding: 10px 18px;
        font-size: 0.85rem;
        flex: 0 0 auto;
        white-space: nowrap;
    }

    .contact-form {
        padding: 30px;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
}

@media (max-width: 480px) {
    :root {
        --section-padding: 40px;
        --header-height: 62px;
    }

    .container {
        padding: 0 20px;
    }

    /* 히어로 섹션 */
    .hero {
        height: auto;
        min-height: 450px;
        padding: 40px 0;
    }

    .hero-title {
        font-size: 1.75rem;
        line-height: 1.2;
    }

    .hero-divider {
        width: 50px;
        height: 3px;
        margin-bottom: 20px;
    }

    .hero-description {
        font-size: 0.85rem;
        margin-bottom: 12px;
    }

    .hero-subtitle {
        font-size: 0.95rem;
        margin-bottom: 30px;
    }

    .hero-stats {
        gap: 15px;
        flex-wrap: wrap;
        margin-bottom: 30px;
    }

    .hero-stat {
        min-width: calc(50% - 7.5px);
    }

    .stat-number {
        font-size: 1.6rem;
    }

    .stat-label {
        font-size: 0.75rem;
    }

    .hero-btn {
        padding: 16px 36px;
        font-size: 0.85rem;
        width: 100%;
        max-width: 280px;
        text-align: center;
    }

    /* 섹션 타이틀 */
    .section-title {
        font-size: 1.6rem;
        margin-bottom: 40px;
    }

    .section-title::before {
        width: 40px;
        height: 3px;
        top: -15px;
    }

    .section-title-simple {
        font-size: 1.5rem;
        margin-bottom: 30px;
    }

    /* 회사소개 */
    .about-text h3 {
        font-size: 1.4rem;
    }

    .about-text p {
        font-size: 1rem;
        line-height: 1.7;
    }

    .stat-item {
        padding: 25px 15px;
    }

    .stat-item h4 {
        font-size: 2.2rem;
    }

    .stat-item p {
        font-size: 0.85rem;
    }

    /* 프로젝트 필터 */
    .project-filters {
        gap: 8px;
        justify-content: flex-start;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: none;
        -ms-overflow-style: none;
        padding-bottom: 4px;
    }

    .project-filters::-webkit-scrollbar {
        display: none;
    }

    .filter-btn {
        padding: 10px 18px;
        font-size: 0.8rem;
        flex: 0 0 auto;
        min-width: auto;
        white-space: nowrap;
    }

    .project-card {
        height: 320px;
        border-radius: 8px;
    }

    .project-info {
        padding: 20px;
    }

    .project-info h3 {
        font-size: 1.2rem;
    }

    .project-info p {
        font-size: 0.85rem;
    }

    /* 적용 분야 */
    .applications-grid {
        gap: 20px;
    }

    .application-item {
        padding: 30px 20px;
    }

    .application-number {
        font-size: 3rem;
        top: 20px;
        right: 20px;
    }

    .application-content h3 {
        font-size: 1.3rem;
        padding-right: 0;
    }

    .application-list li {
        font-size: 0.9rem;
        padding: 8px 0;
    }

    /* 인증서 필터 */
    .cert-filters {
        gap: 6px;
    }

    .cert-filter-btn {
        padding: 10px 16px;
        font-size: 0.75rem;
        flex: 0 1 auto;
    }

    /* 인증서 카드 */
    .certifications-grid {
        gap: 20px;
    }

    .cert-card {
        border-radius: 12px;
    }

    .cert-header {
        padding: 25px 20px 20px;
    }

    .cert-icon {
        width: 50px;
        height: 50px;
        font-size: 1.5rem;
        top: 20px;
        right: 20px;
    }

    .cert-header h3 {
        font-size: 1.2rem;
        padding-right: 60px;
    }

    .cert-status {
        padding: 6px 14px;
        font-size: 0.7rem;
    }

    .cert-issuer {
        font-size: 0.85rem;
        padding: 8px 12px;
    }

    .cert-body {
        padding: 20px;
    }

    .cert-description {
        font-size: 0.9rem;
        line-height: 1.65;
    }

    .cert-meta {
        padding: 18px;
        gap: 15px;
    }

    .cert-meta-label {
        font-size: 0.65rem;
    }

    .cert-meta-value {
        font-size: 0.9rem;
    }

    .cert-footer {
        padding: 18px 20px;
    }

    /* 뉴스 */
    .news-grid {
        gap: 20px;
    }

    .news-card {
        border-radius: 8px;
    }

    .news-image {
        height: 180px;
    }

    .news-content {
        padding: 20px;
    }

    .news-content h3 {
        font-size: 1.2rem;
    }

    .news-content p {
        font-size: 0.9rem;
        line-height: 1.6;
    }

    .news-card-more {
        min-height: 280px;
    }

    .news-more-icon {
        font-size: 4rem;
    }

    .news-more-content h3 {
        font-size: 1.3rem;
    }

    .news-more-content p {
        font-size: 0.9rem;
    }

    /* 문의 */
    .contact-form {
        padding: 25px 20px;
    }

    .contact-info {
        padding: 35px 25px;
    }

    .contact-info h3 {
        font-size: 1.4rem;
    }

    .form-group {
        margin-bottom: 20px;
    }

    .form-group label {
        font-size: 0.85rem;
        margin-bottom: 8px;
    }

    .form-group input,
    .form-group textarea {
        padding: 12px 16px;
        font-size: 1rem;
    }

    .submit-btn {
        padding: 14px;
        font-size: 0.95rem;
    }

    /* 푸터 */
    .footer {
        padding: 50px 0 20px;
    }

    .footer-content {
        gap: 30px;
        margin-bottom: 30px;
    }

    .footer-section h4 {
        font-size: 1.2rem;
    }

    .footer-section p,
    .footer-section ul li a {
        font-size: 0.9rem;
    }

    /* 스크롤 탑 버튼 */
    .scroll-top {
        width: 48px;
        height: 48px;
        bottom: 20px;
        right: 20px;
        font-size: 1.2rem;
    }
}

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

.fade-in-up {
    animation: fadeInUp 0.8s ease-out;
}

/* 모바일 터치 최적화 */
@media (max-width: 768px) {
    /* 터치 타겟 크기 최소 44px */
    button,
    a.hero-btn,
    .nav-link,
    .filter-btn,
    .cert-filter-btn,
    .lang-btn {
        min-height: 44px;
        display: inline-flex;
        align-items: center;
        justify-content: center;
    }

    /* 스크롤 성능 최적화 */
    .hero-background,
    .project-image,
    .news-image {
        will-change: transform;
        transform: translateZ(0);
    }

    /* 이미지 최적화 */
    img {
        max-width: 100%;
        height: auto;
    }

    /* 터치 하이라이트 제거 */
    * {
        -webkit-tap-highlight-color: transparent;
    }

    /* 텍스트 선택 개선 */
    .hero-title,
    .section-title {
        -webkit-user-select: none;
        user-select: none;
    }
}

/* 작은 모바일 추가 최적화 */
@media (max-width: 360px) {
    :root {
        --section-padding: 35px;
        --header-height: 59px;
    }

    .container {
        padding: 0 16px;
    }

    .hero-title {
        font-size: 1.5rem;
    }

    .hero-btn {
        width: 100%;
        padding: 14px 24px;
    }

    .section-title {
        font-size: 1.4rem;
    }

    .filter-btn,
    .cert-filter-btn {
        padding: 8px 12px;
        font-size: 0.7rem;
    }

    .nav-logo img {
        height: 42px;
    }

    .lang-btn {
        padding: 4px 7px;
        font-size: 0.65rem;
    }

    .project-card {
        height: 280px;
    }

    .cert-header h3 {
        font-size: 1.1rem;
    }

    .news-content h3 {
        font-size: 1.1rem;
    }
}