/* ==========================================================================
   The Digital Authority Hub - Engineering Safety Consulting Platform
   CSS Styling Sheet (Strict Engineering, Academic, Academic & Tech Palette)
   ========================================================================== */

:root {
    /* Color Palette */
    --primary-navy: #002A5C;        /* Deep Navy Blue - Trust, Expertise, Stability */
    --navy-dark: #001A3B;           /* Darker Navy for backgrounds */
    --navy-light: #0A3D7A;          /* Lighter Navy for borders/hover */
    
    --bg-secondary: #F9F9F9;        /* Calm Gray/White for clean readability */
    --surface-white: #FFFFFF;
    --text-main: #222222;           /* Structured Dark Gray */
    --text-muted: #666666;
    --border-color: #E2E8F0;
    
    --accent-teal: #00BCD4;         /* Electric Teal - Only for CTA & Tech Principle visuals */
    --accent-teal-glow: rgba(0, 188, 212, 0.25);
    --accent-teal-hover: #008BA3;

    /* Fonts */
    --font-main: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;

    /* Shadows & Effects */
    --shadow-sm: 0 2px 4px rgba(0, 42, 92, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 42, 92, 0.08);
    --shadow-lg: 0 12px 32px rgba(0, 42, 92, 0.12);
    --shadow-accent: 0 0 20px rgba(0, 188, 212, 0.4);

    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-main);
    background-color: var(--surface-white);
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    width: 100%;
    max-width: 1240px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Typography Rules */
h1, h2, h3, h4, h5 {
    color: var(--primary-navy);
    font-weight: 700;
    line-height: 1.3;
}

a {
    color: inherit;
    text-decoration: none;
}

/* BUTTONS & CTA (ACCENT COLOR RESERVED) */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    font-size: 0.95rem;
    font-weight: 700;
    border-radius: var(--radius-sm);
    border: 1px solid transparent;
    cursor: pointer;
    transition: all 0.25s ease;
    text-align: center;
    font-family: var(--font-main);
}

.btn-lg {
    padding: 16px 32px;
    font-size: 1.05rem;
}

/* ONLY CTA USES ELECTRIC TEAL */
.btn-accent {
    background-color: var(--accent-teal);
    color: #000000;
    font-weight: 800;
    box-shadow: var(--shadow-accent);
}

.btn-accent:hover {
    background-color: #00d8f3;
    transform: translateY(-2px);
    box-shadow: 0 0 25px rgba(0, 188, 212, 0.6);
}

.btn-outline {
    background-color: transparent;
    color: var(--primary-navy);
    border-color: var(--primary-navy);
}

.btn-outline:hover {
    background-color: var(--primary-navy);
    color: var(--surface-white);
    transform: translateY(-2px);
}

.btn-block {
    width: 100%;
}

.pulse-dot {
    width: 8px;
    height: 8px;
    background-color: #000;
    border-radius: 50%;
    display: inline-block;
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(0, 0, 0, 0.7); }
    70% { transform: scale(1); box-shadow: 0 0 0 8px rgba(0, 0, 0, 0); }
    100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(0, 0, 0, 0); }
}

/* HEADER & NAVIGATION */
.header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background-color: var(--primary-navy);
    color: var(--surface-white);
    border-bottom: 1px solid var(--navy-light);
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: 1360px;
    margin: 0 auto;
    padding: 14px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
}

.logo {
    font-weight: 900;
    font-size: 1.25rem;
    letter-spacing: -0.5px;
    display: flex;
    align-items: center;
    gap: 8px;
    white-space: nowrap;
}

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

.badge {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    background-color: var(--navy-light);
    color: var(--accent-teal);
    padding: 2px 6px;
    border-radius: 3px;
    border: 1px solid var(--accent-teal);
}

/* HEADER SEARCH BAR */
.search-bar {
    position: relative;
    flex: 1;
    max-width: 400px;
    display: flex;
    align-items: center;
}

.search-bar input {
    width: 100%;
    background-color: var(--navy-dark);
    border: 1px solid var(--navy-light);
    color: var(--surface-white);
    padding: 8px 36px 8px 36px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    outline: none;
    transition: border-color 0.2s ease;
}

.search-bar input:focus {
    border-color: var(--accent-teal);
}

.search-icon {
    position: absolute;
    left: 10px;
    color: var(--text-muted);
}

.search-shortcut {
    position: absolute;
    right: 10px;
    font-family: var(--font-mono);
    font-size: 0.7rem;
    color: var(--text-muted);
    background: rgba(255, 255, 255, 0.1);
    padding: 2px 4px;
    border-radius: 2px;
}

.nav-menu {
    display: flex;
    gap: 20px;
}

.nav-link {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9rem;
    font-weight: 500;
    transition: color 0.2s ease;
}

.nav-link:hover, .nav-link.active {
    color: var(--accent-teal);
}

.header-cta {
    white-space: nowrap;
}

/* HERO SECTION */
.hero-section {
    position: relative;
    background-color: var(--primary-navy);
    color: var(--surface-white);
    padding: 80px 0 100px;
    overflow: hidden;
}

.hero-grid-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        linear-gradient(rgba(0, 188, 212, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 188, 212, 0.05) 1px, transparent 1px);
    background-size: 40px 40px;
    pointer-events: none;
}

.hero-container {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 40px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.tech-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--accent-teal);
    background: rgba(0, 188, 212, 0.1);
    border: 1px solid var(--accent-teal);
    padding: 4px 10px;
    border-radius: 20px;
    margin-bottom: 20px;
}

.hero-title {
    font-size: 2.3rem;
    color: #FFFFFF;
    line-height: 1.35;
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.hero-title .highlight {
    color: var(--accent-teal);
    background: linear-gradient(180deg, transparent 70%, rgba(0, 188, 212, 0.2) 70%);
}

.hero-subtitle {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 32px;
    font-weight: 300;
}

.hero-cta-group {
    display: flex;
    gap: 16px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.hero-cta-group .btn-outline {
    color: var(--surface-white);
    border-color: rgba(255, 255, 255, 0.4);
}

.hero-cta-group .btn-outline:hover {
    background-color: rgba(255, 255, 255, 0.1);
    border-color: #FFFFFF;
}

/* HERO METRICS */
.hero-metrics {
    display: flex;
    align-items: center;
    gap: 24px;
    background: rgba(0, 26, 59, 0.6);
    padding: 16px 24px;
    border-radius: var(--radius-md);
    border: 1px solid var(--navy-light);
}

.metric-item {
    display: flex;
    flex-direction: column;
}

.metric-value {
    font-family: var(--font-mono);
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--accent-teal);
}

.metric-label {
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.7);
}

.metric-divider {
    width: 1px;
    height: 36px;
    background-color: var(--navy-light);
}

/* HERO ENGINEERING DIAGRAM */
.hero-diagram-card {
    background-color: var(--navy-dark);
    border: 1px solid var(--navy-light);
    border-radius: var(--radius-md);
    padding: 20px;
    box-shadow: var(--shadow-lg);
}

.diagram-header {
    display: flex;
    align-items: center;
    gap: 8px;
    border-bottom: 1px solid var(--navy-light);
    padding-bottom: 12px;
    margin-bottom: 20px;
}

.status-indicator {
    width: 8px;
    height: 8px;
    background-color: #22c55e;
    border-radius: 50%;
}

.diagram-title {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--accent-teal);
    letter-spacing: 0.5px;
}

.diagram-body {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.flow-step {
    width: 100%;
}

.step-box {
    background: rgba(255, 255, 255, 0.03);
    border: 1px dashed rgba(255, 255, 255, 0.2);
    padding: 12px;
    border-radius: var(--radius-sm);
    display: flex;
    flex-direction: column;
}

.step-box.accent-border {
    border: 1px solid var(--accent-teal);
    background: rgba(0, 188, 212, 0.08);
}

.step-code {
    font-family: var(--font-mono);
    font-size: 0.65rem;
    color: var(--accent-teal);
}

.step-box strong {
    font-size: 0.95rem;
    color: #FFFFFF;
}

.step-box small {
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.6);
}

.flow-arrow {
    text-align: center;
    color: var(--accent-teal);
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.diagram-footer {
    margin-top: 16px;
    padding-top: 12px;
    border-top: 1px solid var(--navy-light);
    font-size: 0.7rem;
    color: rgba(255, 255, 255, 0.5);
    font-family: var(--font-mono);
}

/* SECTION HEADERS */
.section-header {
    margin-bottom: 48px;
}

.section-tag {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--primary-navy);
    font-weight: 600;
    letter-spacing: 1px;
}

.section-title {
    font-size: 2rem;
    margin: 8px 0 12px;
}

.section-desc {
    color: var(--text-muted);
    font-size: 1rem;
}

.text-center {
    text-align: center;
}

/* TRUST BUILDER SECTION */
.trust-section {
    padding: 90px 0;
    background-color: var(--bg-secondary);
}

.trust-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-bottom: 60px;
}

.trust-card {
    background: var(--surface-white);
    padding: 32px 24px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
}

.trust-number {
    font-family: var(--font-mono);
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--primary-navy);
    margin-bottom: 12px;
}

.trust-card h3 {
    font-size: 1.15rem;
    margin-bottom: 8px;
}

.trust-card p {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* MATRIX TABLE UI */
.matrix-box {
    background: var(--surface-white);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px;
    box-shadow: var(--shadow-sm);
}

.matrix-title {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--primary-navy);
    margin-bottom: 16px;
    text-transform: uppercase;
}

.table-responsive {
    overflow-x: auto;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.9rem;
    text-align: left;
}

.data-table th, .data-table td {
    padding: 14px 16px;
    border-bottom: 1px solid var(--border-color);
}

.data-table th {
    background-color: var(--bg-secondary);
    color: var(--primary-navy);
    font-weight: 700;
}

.highlight-cell {
    background-color: rgba(0, 188, 212, 0.06);
    color: var(--primary-navy);
    font-weight: 600;
    border-left: 2px solid var(--accent-teal);
}

/* PAIN POINT & SOLUTION SECTION */
.pain-section {
    padding: 90px 0;
    background-color: var(--surface-white);
}

.pain-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.pain-card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 28px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.pain-badge {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 700;
    color: #dc2626;
    margin-bottom: 12px;
}

.pain-card h3 {
    font-size: 1.2rem;
    margin-bottom: 12px;
}

.pain-card p {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 20px;
}

.solution-box {
    background: var(--surface-white);
    border: 1px solid var(--primary-navy);
    border-radius: var(--radius-sm);
    padding: 16px;
    margin-top: auto;
}

.sol-tag {
    display: block;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--accent-teal-hover);
    font-weight: 700;
    margin-bottom: 4px;
}

.solution-box strong {
    display: block;
    font-size: 0.95rem;
    color: var(--primary-navy);
    margin-bottom: 4px;
}

.solution-box p {
    font-size: 0.85rem;
    margin-bottom: 0;
    color: var(--text-main);
}

/* PRICING / SOLUTIONS PACKAGES SECTION */
.pricing-section {
    padding: 90px 0;
    background-color: var(--primary-navy);
    color: var(--surface-white);
}

.pricing-section .section-tag {
    color: var(--accent-teal);
}

.pricing-section .section-title {
    color: #FFFFFF;
}

.pricing-section .section-desc {
    color: rgba(255, 255, 255, 0.7);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 28px;
    align-items: stretch;
}

.price-card {
    background-color: var(--navy-dark);
    border: 1px solid var(--navy-light);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    display: flex;
    flex-direction: column;
    position: relative;
}

.price-card.featured {
    border: 2px solid var(--accent-teal);
    box-shadow: 0 0 30px rgba(0, 188, 212, 0.2);
    transform: translateY(-8px);
}

.popular-badge {
    position: absolute;
    top: -12px;
    right: 28px;
    background-color: var(--accent-teal);
    color: #000;
    font-family: var(--font-mono);
    font-size: 0.7rem;
    font-weight: 800;
    padding: 4px 12px;
    border-radius: 12px;
}

.card-level {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--accent-teal);
    margin-bottom: 8px;
}

.card-title {
    font-size: 1.35rem;
    color: #FFFFFF;
    margin-bottom: 4px;
}

.price-sub {
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.6);
    margin-bottom: 24px;
}

.price-value {
    font-family: var(--font-mono);
    font-size: 1.4rem;
    font-weight: 700;
    color: #FFFFFF;
    border-bottom: 1px solid var(--navy-light);
    padding-bottom: 20px;
    margin-bottom: 24px;
}

.price-unit {
    font-size: 0.75rem;
    font-weight: normal;
    color: rgba(255, 255, 255, 0.6);
}

.feature-list {
    list-style: none;
    margin-bottom: 32px;
    flex: 1;
}

.feature-list li {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 12px;
    display: flex;
    align-items: flex-start;
    gap: 8px;
}

.feature-list .check {
    color: var(--accent-teal);
    font-weight: bold;
}

/* PROCESS SECTION */
.process-section {
    padding: 90px 0;
    background-color: var(--bg-secondary);
}

.process-flow {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-top: 40px;
}

.process-step {
    flex: 1;
    background: var(--surface-white);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px 20px;
    text-align: left;
    box-shadow: var(--shadow-sm);
}

.step-num {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--accent-teal);
    margin-bottom: 8px;
}

.step-content h4 {
    font-size: 1.05rem;
    margin-bottom: 6px;
}

.step-content p {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.process-connector {
    color: var(--primary-navy);
    font-size: 1.2rem;
    font-weight: bold;
}

/* ARCHIVE SECTION */
.archive-section {
    padding: 90px 0;
    background-color: var(--surface-white);
}

.archive-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.archive-card {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px;
    transition: transform 0.2s ease;
}

.archive-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.card-meta {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-bottom: 8px;
}

.archive-card h3 {
    font-size: 1.1rem;
    margin-bottom: 12px;
    line-height: 1.4;
}

.archive-card p {
    font-size: 0.88rem;
    color: var(--text-muted);
    margin-bottom: 16px;
}

.read-more {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--primary-navy);
}

.read-more:hover {
    color: var(--accent-teal-hover);
}

/* FOOTER */
.footer {
    background-color: var(--navy-dark);
    color: rgba(255, 255, 255, 0.7);
}

.footer-cta-banner {
    background-color: var(--primary-navy);
    border-bottom: 1px solid var(--navy-light);
    padding: 40px 0;
}

.footer-cta-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
}

.footer-cta-content h2 {
    color: #FFFFFF;
    font-size: 1.4rem;
}

.footer-cta-content p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.95rem;
}

.footer-body {
    padding: 60px 24px;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
}

.footer-col h4 {
    color: #FFFFFF;
    font-size: 1rem;
    margin-bottom: 16px;
}

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

.footer-col li {
    margin-bottom: 8px;
}

.footer-col a {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.88rem;
}

.footer-col a:hover {
    color: var(--accent-teal);
}

/* MODAL OVERLAY & CONTAINER */
.modal-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 26, 59, 0.8);
    backdrop-filter: blur(4px);
    z-index: 2000;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.modal-overlay.active {
    display: flex;
}

.modal-container {
    background: var(--surface-white);
    border-radius: var(--radius-lg);
    max-width: 520px;
    width: 100%;
    padding: 32px;
    position: relative;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--primary-navy);
}

.modal-close {
    position: absolute;
    top: 16px;
    right: 20px;
    background: none;
    border: none;
    font-size: 1.8rem;
    color: var(--text-muted);
    cursor: pointer;
}

.modal-header {
    margin-bottom: 24px;
}

.modal-header h3 {
    font-size: 1.4rem;
    margin: 6px 0;
}

.modal-header p {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.form-group {
    margin-bottom: 16px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.form-group label {
    display: block;
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--primary-navy);
    margin-bottom: 6px;
}

.form-group input, .form-group select, .form-group textarea {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    font-family: var(--font-main);
    outline: none;
}

.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
    border-color: var(--primary-navy);
}

/* RESPONSIVE DESIGN */
@media (max-width: 992px) {
    .hero-container {
        grid-template-columns: 1fr;
    }

    .trust-grid, .pain-grid, .pricing-grid, .archive-grid {
        grid-template-columns: 1fr;
    }

    .pricing-card.featured {
        transform: none;
    }

    .process-flow {
        flex-direction: column;
    }

    .process-connector {
        transform: rotate(90deg);
        margin: 8px 0;
    }

    .footer-body {
        grid-template-columns: 1fr;
    }

    .search-bar {
        display: none;
    }
}