/* ===== CSS Variables ===== */
:root {
    --primary: #0066FF;
    --primary-dark: #0052CC;
    --primary-light: #E6F0FF;
    --secondary: #1E293B;
    --accent: #00D4AA;
    --accent-light: #E6FFF9;
    --text-primary: #1E293B;
    --text-secondary: #64748B;
    --text-light: #94A3B8;
    --bg-white: #FFFFFF;
    --bg-light: #F8FAFC;
    --bg-dark: #0F172A;
    --border: #E2E8F0;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --radius: 12px;
    --radius-lg: 20px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, sans-serif;
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-primary);
    background: var(--bg-white);
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.3;
    color: var(--text-primary);
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.5rem); }

p {
    color: var(--text-secondary);
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: var(--radius);
    border: none;
    cursor: pointer;
    transition: var(--transition);
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: var(--bg-light);
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background: var(--bg-white);
    border-color: var(--primary);
    color: var(--primary);
}

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

.btn-light:hover {
    background: var(--primary-light);
    transform: translateY(-2px);
}

.btn-outline-light {
    background: transparent;
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
}

.btn-outline-light:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: white;
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text-primary);
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.25rem;
}

.logo-text {
    font-size: 1.1rem;
    font-weight: 400;
    color: var(--text-secondary);
}

.logo-text strong {
    color: var(--text-primary);
    font-weight: 700;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
    list-style: none;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.95rem;
    transition: var(--transition);
}

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

.nav-cta {
    background: var(--primary);
    color: white !important;
    padding: 10px 20px;
    border-radius: var(--radius);
}

.nav-cta:hover {
    background: var(--primary-dark);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-primary);
    cursor: pointer;
}

/* ===== Hero Section ===== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 0 80px;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, var(--bg-light) 0%, var(--bg-white) 100%);
    z-index: -1;
}

.hero-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(0, 102, 255, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 102, 255, 0.03) 1px, transparent 1px);
    background-size: 60px 60px;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--accent-light);
    color: #00A080;
    padding: 8px 16px;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 24px;
}

.hero-badge i {
    font-size: 1rem;
}

.hero h1 {
    margin-bottom: 24px;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
    line-height: 1.8;
}

.hero-stats {
    display: flex;
    gap: 40px;
    margin-bottom: 40px;
}

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

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary);
    line-height: 1;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: 4px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

/* Dashboard Preview */
.hero-visual {
    position: relative;
}

.dashboard-preview {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    overflow: hidden;
    border: 1px solid var(--border);
}

.dashboard-header {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: var(--bg-light);
    border-bottom: 1px solid var(--border);
}

.dashboard-dots {
    display: flex;
    gap: 6px;
}

.dashboard-dots span {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--border);
}

.dashboard-dots span:first-child { background: #FF5F56; }
.dashboard-dots span:nth-child(2) { background: #FFBD2E; }
.dashboard-dots span:last-child { background: #27CA40; }

.dashboard-title {
    font-size: 0.8rem;
    color: var(--text-secondary);
    flex: 1;
    text-align: center;
}

.dashboard-content {
    display: flex;
    min-height: 300px;
}

.dashboard-sidebar {
    width: 60px;
    background: var(--secondary);
    padding: 16px 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.sidebar-item {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: var(--transition);
}

.sidebar-item:hover,
.sidebar-item.active {
    background: var(--primary);
    color: white;
}

.dashboard-main {
    flex: 1;
    padding: 20px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

.dashboard-card {
    background: var(--bg-light);
    padding: 16px;
    border-radius: var(--radius);
}

.card-header {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.card-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary);
}

.card-value span {
    font-size: 1rem;
    color: var(--text-secondary);
}

.dashboard-timeline {
    grid-column: span 2;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.timeline-bar {
    height: 24px;
    background: linear-gradient(90deg, var(--primary) 30%, var(--accent) 30% 60%, var(--primary-light) 60%);
    border-radius: 6px;
    opacity: 0.8;
}

.timeline-bar:nth-child(2) {
    background: linear-gradient(90deg, var(--accent) 20%, var(--primary) 20% 70%, var(--primary-light) 70%);
}

.timeline-bar:nth-child(3) {
    background: linear-gradient(90deg, var(--primary-light) 40%, var(--primary) 40% 80%, var(--accent) 80%);
}

/* ===== Section Header ===== */
.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 60px;
}

.section-header.light h2,
.section-header.light p {
    color: white;
}

.section-badge {
    display: inline-block;
    background: var(--primary-light);
    color: var(--primary);
    padding: 6px 16px;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 16px;
}

.section-header.light .section-badge {
    background: rgba(255, 255, 255, 0.1);
    color: white;
}

/* ===== Problems Section ===== */
.problems {
    padding: 100px 0;
    background: var(--bg-light);
}

.problems-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.problem-card {
    background: var(--bg-white);
    padding: 32px 24px;
    border-radius: var(--radius);
    text-align: center;
    border: 1px solid var(--border);
    transition: var(--transition);
}

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

.problem-icon {
    width: 64px;
    height: 64px;
    background: #FEE2E2;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    font-size: 1.5rem;
    color: #DC2626;
}

.problem-card h3 {
    font-size: 1.125rem;
    margin-bottom: 12px;
}

.problem-card p {
    font-size: 0.9rem;
    line-height: 1.6;
}

/* ===== Features Section ===== */
.features {
    padding: 100px 0;
}

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

.feature-card {
    background: var(--bg-white);
    padding: 32px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    transition: var(--transition);
}

.feature-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
}

.feature-card.featured {
    grid-row: span 2;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    border: none;
}

.feature-card.featured h3,
.feature-card.featured p,
.feature-card.featured li {
    color: white;
}

.feature-card.featured .feature-icon {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

.feature-icon {
    width: 56px;
    height: 56px;
    background: var(--primary-light);
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--primary);
    margin-bottom: 20px;
}

.feature-card h3 {
    margin-bottom: 12px;
}

.feature-card p {
    font-size: 0.95rem;
    line-height: 1.7;
}

.feature-list {
    list-style: none;
    margin-top: 20px;
}

.feature-list li {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
    font-size: 0.95rem;
}

.feature-list i {
    color: var(--accent);
    font-size: 1.1rem;
}

.feature-card.featured .feature-list i {
    color: white;
}

/* Schedule Preview */
.schedule-preview {
    margin-top: 20px;
    background: var(--bg-light);
    border-radius: var(--radius);
    padding: 16px;
}

.schedule-row {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 8px;
}

.schedule-row:last-child {
    margin-bottom: 0;
}

.schedule-row .time {
    font-size: 0.75rem;
    color: var(--text-secondary);
    width: 40px;
}

.schedule-block {
    flex: 1;
    padding: 8px 12px;
    border-radius: 6px;
    font-size: 0.8rem;
    font-weight: 600;
    color: white;
}

.schedule-block.morning { background: var(--primary); }
.schedule-block.promo { background: var(--accent); }
.schedule-block.event { background: #8B5CF6; }

/* Platform Icons */
.platform-icons {
    display: flex;
    gap: 12px;
    margin-top: 16px;
    flex-wrap: wrap;
}

.platform-icons span {
    display: flex;
    align-items: center;
    gap: 6px;
    background: var(--bg-light);
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.platform-icons i {
    color: var(--primary);
}

/* ===== Architecture Section ===== */
.architecture {
    padding: 100px 0;
    background: var(--bg-dark);
}

.architecture-diagram {
    max-width: 900px;
    margin: 0 auto;
}

.arch-layer {
    display: flex;
    justify-content: center;
    gap: 40px;
}

.server-layer {
    margin-bottom: 60px;
}

.arch-node {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-lg);
    padding: 24px;
    text-align: center;
    transition: var(--transition);
}

.arch-node:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-4px);
}

.arch-node.central {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    border: none;
    padding: 40px;
}

.node-icon {
    width: 60px;
    height: 60px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    font-size: 1.75rem;
    color: white;
}

.arch-node.central .node-icon {
    width: 80px;
    height: 80px;
    font-size: 2rem;
    background: rgba(255, 255, 255, 0.2);
}

.node-info h4 {
    color: white;
    margin-bottom: 4px;
}

.node-info p {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.875rem;
}

.node-info ul {
    list-style: none;
    margin-top: 16px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
}

.node-info ul li {
    background: rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.8);
    padding: 4px 12px;
    border-radius: 50px;
    font-size: 0.75rem;
}

.arch-connections {
    display: flex;
    justify-content: center;
    gap: 120px;
    margin-bottom: 40px;
}

.connection-line {
    width: 2px;
    height: 40px;
    background: linear-gradient(to bottom, var(--primary), transparent);
}

.client-layer {
    gap: 24px;
}

.client-layer .arch-node {
    flex: 1;
    max-width: 200px;
}

/* ===== Specs Section ===== */
.specs {
    padding: 100px 0;
}

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

.spec-card {
    background: var(--bg-white);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.spec-header {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 20px 24px;
    background: var(--bg-light);
    border-bottom: 1px solid var(--border);
}

.spec-header i {
    font-size: 1.5rem;
    color: var(--primary);
}

.spec-header h3 {
    font-size: 1.125rem;
}

.spec-table {
    width: 100%;
    border-collapse: collapse;
}

.spec-table tr {
    border-bottom: 1px solid var(--border);
}

.spec-table tr:last-child {
    border-bottom: none;
}

.spec-table td {
    padding: 14px 24px;
    font-size: 0.9rem;
}

.spec-table td:first-child {
    color: var(--text-secondary);
    width: 40%;
}

.spec-table td:last-child {
    font-weight: 600;
    color: var(--text-primary);
}

/* ===== Benefits Section ===== */
.benefits {
    padding: 100px 0;
    background: var(--bg-light);
}

.benefits-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.benefit-card {
    background: var(--bg-white);
    padding: 40px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    position: relative;
    transition: var(--transition);
}

.benefit-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
}

.benefit-number {
    font-size: 3rem;
    font-weight: 800;
    color: var(--primary-light);
    position: absolute;
    top: 20px;
    right: 30px;
}

.benefit-card h3 {
    font-size: 1.25rem;
    margin-bottom: 12px;
}

.benefit-card p {
    margin-bottom: 20px;
}

.benefit-metric {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px;
    background: var(--bg-light);
    border-radius: var(--radius);
}

.benefit-metric .before {
    color: var(--text-secondary);
    text-decoration: line-through;
    font-size: 0.9rem;
}

.benefit-metric i {
    color: var(--primary);
}

.benefit-metric .after {
    color: var(--primary);
    font-weight: 700;
}

/* ===== Use Cases Section ===== */
.usecases {
    padding: 100px 0;
}

.usecases-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 20px;
}

.usecase-card {
    background: var(--bg-white);
    padding: 32px 20px;
    border-radius: var(--radius);
    text-align: center;
    border: 1px solid var(--border);
    transition: var(--transition);
}

.usecase-card:hover {
    border-color: var(--primary);
    transform: translateY(-4px);
    box-shadow: var(--shadow);
}

.usecase-card i {
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: 16px;
}

.usecase-card h3 {
    font-size: 1rem;
    margin-bottom: 8px;
}

.usecase-card p {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

/* ===== CTA Section ===== */
.cta {
    padding: 100px 0;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    text-align: center;
}

.cta h2 {
    color: white;
    margin-bottom: 16px;
}

.cta p {
    color: rgba(255, 255, 255, 0.8);
    font-size: 1.125rem;
    margin-bottom: 40px;
}

.cta-actions {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.cta-info {
    display: flex;
    justify-content: center;
    gap: 40px;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 8px;
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.9rem;
}

.info-item i {
    color: white;
}

/* ===== Footer ===== */
.footer {
    background: var(--bg-dark);
    padding: 60px 0 30px;
    color: rgba(255, 255, 255, 0.6);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    gap: 60px;
    margin-bottom: 40px;
}

.footer-brand {
    max-width: 300px;
}

.footer-brand .logo {
    margin-bottom: 16px;
}

.footer-brand .logo-icon {
    background: rgba(255, 255, 255, 0.1);
}

.footer-brand .logo-text {
    color: rgba(255, 255, 255, 0.6);
}

.footer-brand .logo-text strong {
    color: white;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.9rem;
    line-height: 1.7;
}

.footer-links {
    display: flex;
    gap: 80px;
}

.footer-col h4 {
    color: white;
    font-size: 1rem;
    margin-bottom: 20px;
}

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

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

.footer-col a {
    color: rgba(255, 255, 255, 0.5);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

.footer-col a:hover {
    color: white;
}

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

.footer-bottom p {
    color: rgba(255, 255, 255, 0.4);
    font-size: 0.875rem;
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-stats {
        justify-content: center;
    }

    .hero-actions {
        justify-content: center;
    }

    .hero-visual {
        display: none;
    }

    .problems-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .feature-card.featured {
        grid-column: span 2;
        grid-row: auto;
    }

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

    .arch-layer {
        flex-direction: column;
        align-items: center;
    }

    .arch-connections {
        flex-direction: column;
        gap: 0;
        align-items: center;
    }

    .connection-line {
        height: 30px;
    }

    .client-layer .arch-node {
        max-width: 300px;
        width: 100%;
    }

    .usecases-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 24px;
        gap: 16px;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow-lg);
    }

    .nav-links.active {
        display: flex;
    }

    .mobile-menu-btn {
        display: block;
    }

    .hero {
        padding: 100px 0 60px;
        min-height: auto;
    }

    .hero-subtitle br {
        display: none;
    }

    .hero-stats {
        gap: 24px;
    }

    .stat-number {
        font-size: 2rem;
    }

    .problems-grid,
    .features-grid,
    .benefits-grid {
        grid-template-columns: 1fr;
    }

    .feature-card.featured {
        grid-column: auto;
    }

    .usecases-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-content {
        flex-direction: column;
        gap: 40px;
    }

    .footer-links {
        gap: 40px;
    }

    .cta h2 br {
        display: none;
    }

    .cta-info {
        flex-direction: column;
        gap: 16px;
    }
}

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

.animate-in {
    animation: fadeInUp 0.6s ease forwards;
}