:root {
    /* Color Palette */
    --color-navy-dark: #000D1A;
    --color-navy-bg: #001F3F;
    --color-navy-light: #003366;
    --color-silver: #C0C0C0;
    --color-white: #FFFFFF;
    --color-accent: #E63946;
    /* Safety/Disaster Alert Accent */

    /* Effects */
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-blur: blur(15px);
    --shadow-premium: 0 10px 30px rgba(0, 0, 0, 0.5);

    /* Typography */
    --font-major: 'Noto Sans KR', sans-serif;
    --font-minor: 'Inter', sans-serif;
}

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

body {
    background-color: var(--color-navy-bg);
    color: var(--color-white);
    font-family: var(--font-major);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Utility Classes */
.container {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 40px;
}

.en-sub {
    font-family: var(--font-minor);
    font-size: 0.85em;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    opacity: 0.7;
    display: block;
    margin-top: 4px;
}

/* Shared Components */
.section-title {
    text-align: center;
    margin-bottom: 60px;
}

.section-title h2 {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

/* Header & Nav */
header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur);
    border-bottom: 1px solid var(--glass-border);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 90px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 900;
    letter-spacing: -0.05em;
}

.nav-links {
    display: flex;
    gap: 40px;
    list-style: none;
}

.nav-links a {
    text-decoration: none;
    color: var(--color-white);
    font-weight: 600;
    font-size: 1rem;
    transition: opacity 0.3s;
    text-align: center;
}

.nav-links a:hover {
    opacity: 0.7;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    padding-top: 150px;
    background: linear-gradient(rgba(0, 13, 26, 0.7), rgba(0, 13, 26, 0.7)),
        url('https://images.unsplash.com/photo-1551818255-e6e10975bc17?auto=format&fit=crop&q=80&w=1920') center/cover no-repeat;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 70% 30%, rgba(230, 57, 70, 0.05) 0%, transparent 40%);
    pointer-events: none;
}

.hero-content h1 {
    font-size: 4.5rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
    letter-spacing: -0.03em;
}

.hero-content p {
    font-size: 1.25rem;
    max-width: 700px;
    margin-bottom: 40px;
    opacity: 0.9;
}

.badge {
    display: inline-block;
    padding: 6px 16px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 100px;
    font-weight: 600;
    margin-bottom: 20px;
}

.hero-actions {
    display: flex;
    gap: 20px;
}

.btn {
    padding: 16px 32px;
    border-radius: 12px;
    font-weight: 700;
    text-decoration: none;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: inline-block;
}

.btn-primary {
    background: var(--color-white);
    color: var(--color-navy-bg);
}

.btn-primary:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.3);
}

.btn-secondary {
    background: var(--glass-bg);
    color: var(--color-white);
    border: 1px solid var(--glass-border);
    backdrop-filter: var(--glass-blur);
}

.btn-secondary:hover {
    background: var(--glass-border);
}

.signal-pattern {
    position: absolute;
    top: 50%;
    right: -10%;
    width: 60%;
    height: 60%;
    background: repeating-radial-gradient(circle, transparent 0, transparent 40px, var(--glass-border) 41px, transparent 42px);
    opacity: 0.3;
    pointer-events: none;
    transform: translateY(-50%);
    animation: pulseSignal 8s ease-in-out infinite;
}

@keyframes pulseSignal {

    0%,
    100% {
        transform: translateY(-50%) scale(1);
        opacity: 0.2;
    }

    50% {
        transform: translateY(-50%) scale(1.1);
        opacity: 0.5;
    }
}

/* Services Section - Bento Grid */
.bento-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: repeat(2, minmax(250px, auto));
    gap: 24px;
}

.bento-item {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 32px;
    padding: 40px;
    position: relative;
    overflow: hidden;
    transition: all 0.4s ease;
    backdrop-filter: var(--glass-blur);
}

.bento-item:hover {
    transform: scale(1.02);
    border-color: rgba(255, 255, 255, 0.3);
    box-shadow: var(--shadow-premium);
}

.bento-item .icon {
    font-size: 2.5rem;
    margin-bottom: 20px;
}

.bento-item h3 {
    font-size: 1.75rem;
    margin-bottom: 8px;
}

.bento-item p {
    font-size: 1rem;
    opacity: 0.7;
}

.bento-item.disaster {
    /* Aligned with other services for balance */
    grid-column: span 1;
}

.trust-badge {
    position: absolute;
    top: 30px;
    right: 30px;
    background: var(--color-accent);
    color: white;
    padding: 4px 12px;
    border-radius: 6px;
    font-weight: 800;
    font-size: 0.75rem;
    letter-spacing: 0.1em;
}

@media (max-width: 1024px) {
    .bento-grid {
        grid-template-columns: 1fr 1fr;
    }

    .bento-item.disaster {
        grid-column: span 2;
    }
}

@media (max-width: 768px) {
    .hero-content h1 {
        font-size: 3rem;
    }

    .bento-grid {
        grid-template-columns: 1fr;
    }

    .bento-item.disaster {
        grid-column: span 1;
    }
}

/* Shared Layout */
section {
    padding: 120px 0;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fade-in {
    animation: fadeIn 1s forwards;
}

/* Disaster Management Showcase */
.disaster-showcase {
    background: #000D1A;
    position: relative;
    overflow: hidden;
}

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

.showcase-text h2 {
    font-size: 3rem;
    margin-bottom: 24px;
    line-height: 1.2;
}

.showcase-text p {
    font-size: 1.1rem;
    opacity: 0.8;
    margin-bottom: 40px;
}

.feature-list {
    list-style: none;
}

.feature-list li {
    margin-bottom: 24px;
    padding-left: 20px;
    border-left: 3px solid var(--color-accent);
}

.feature-list li strong {
    display: block;
    font-size: 1.2rem;
    color: var(--color-white);
}

.showcase-visual {
    position: relative;
    height: 400px;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* Radar Animation */
.radar {
    width: 300px;
    height: 300px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    position: relative;
    background: radial-gradient(circle, rgba(230, 57, 70, 0.05) 0%, transparent 70%);
}

.radar::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 150px;
    height: 150px;
    background: linear-gradient(90deg, transparent 50%, rgba(230, 57, 70, 0.4) 100%);
    border-radius: 100% 0 0 0;
    transform-origin: top left;
    animation: rotate 4s linear infinite;
}

@keyframes rotate {
    from {
        transform: rotate(0deg);
    }

    to {
        transform: rotate(360deg);
    }
}

/* Knowledge & Insights - Book Cards */
.book-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 40px;
}

.book-card {
    display: flex;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    overflow: hidden;
    transition: transform 0.3s;
}

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

.book-cover {
    width: 180px;
    min-height: 240px;
    background: linear-gradient(135deg, #2c3e50 0%, #000000 100%);
    padding: 20px;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    border-right: 1px solid var(--glass-border);
}

.book-cover.modern {
    background: linear-gradient(135deg, #003366 0%, #001F3F 100%);
}

.book-cover .year {
    font-size: 0.8rem;
    opacity: 0.6;
    margin-bottom: 10px;
}

.book-cover h4 {
    font-size: 1.1rem;
    line-height: 1.3;
}

.book-info {
    padding: 30px;
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.book-info h5 {
    font-size: 1.4rem;
    margin-bottom: 12px;
}

.book-info p {
    font-size: 0.95rem;
    opacity: 0.7;
    margin-bottom: 24px;
}

.btn-text {
    color: var(--color-white);
    text-decoration: none;
    font-weight: 700;
    font-size: 0.9rem;
}

/* Footer & Partner Marquee */
footer {
    background: var(--color-navy-dark);
    padding: 100px 0 40px;
    border-top: 1px solid var(--glass-border);
}

.partner-marquee {
    overflow: hidden;
    margin-bottom: 80px;
    padding: 20px 0;
    border-top: 1px solid var(--glass-border);
    border-bottom: 1px solid var(--glass-border);
}

.marquee-content {
    display: flex;
    align-items: center;
    gap: 150px;
    animation: scroll 30s linear infinite;
    width: max-content;
}

.partner-text {
    color: #FFFFFF;
    font-size: 1.8rem;
    font-weight: 900;
    letter-spacing: 0.15em;
    opacity: 0.9;
    transition: opacity 0.3s;
}

.partner-text:hover {
    opacity: 1;
}

@keyframes scroll {
    from {
        transform: translateX(0);
    }

    to {
        transform: translateX(-50%);
    }
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1.5fr;
    gap: 80px;
    margin-bottom: 60px;
}

.footer-col h4 {
    margin-bottom: 24px;
    font-size: 1.1rem;
    letter-spacing: 0.1em;
}

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

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

.footer-col ul a {
    text-decoration: none;
    color: var(--color-white);
    opacity: 0.6;
    transition: opacity 0.3s;
}

.footer-col ul a:hover {
    opacity: 1;
}

.footer-bottom {
    text-align: center;
    padding-top: 40px;
    border-top: 1px solid var(--glass-border);
    font-size: 0.85rem;
    opacity: 0.5;
}

@media (max-width: 1024px) {
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .book-card {
        flex-direction: column;
    }

    .book-cover {
        width: 100%;
        height: 200px;
    }
}