/* ========================================
   IoT Center Model - Corporate Website
   Clean, Modern, Professional Design
   ======================================== */

/* CSS Custom Properties */
:root {
    /* Colors - Neutral with blue accents */
    --color-white: #ffffff;
    --color-gray-50: #f9fafb;
    --color-gray-100: #f3f4f6;
    --color-gray-200: #e5e7eb;
    --color-gray-300: #d1d5db;
    --color-gray-400: #9ca3af;
    --color-gray-500: #6b7280;
    --color-gray-600: #4b5563;
    --color-gray-700: #374151;
    --color-gray-800: #1f2937;
    --color-gray-900: #111827;

    /* Primary Blue Accent */
    --color-primary-50: #eff6ff;
    --color-primary-100: #dbeafe;
    --color-primary-200: #bfdbfe;
    --color-primary-300: #93c5fd;
    --color-primary-400: #60a5fa;
    --color-primary-500: #3b82f6;
    --color-primary-600: #2563eb;
    --color-primary-700: #1d4ed8;

    /* Center-specific colors (subtle) */
    --color-innovation: #6366f1;
    --color-innovation-light: #eef2ff;
    --color-control: #0891b2;
    --color-control-light: #ecfeff;
    --color-design: #059669;
    --color-design-light: #ecfdf5;

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

    /* Spacing */
    --section-padding: 100px 0;
    --container-max-width: 1200px;

    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-base: 0.3s ease;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 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);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-gray-700);
    background-color: var(--color-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    color: var(--color-gray-900);
    font-weight: 600;
    line-height: 1.3;
}

/* ========================================
   Navigation
   ======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-gray-100);
    transition: var(--transition-base);
}

.nav-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.nav-logo {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--color-gray-900);
    text-decoration: none;
    letter-spacing: -0.025em;
}

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

.nav-menu a {
    color: var(--color-gray-600);
    text-decoration: none;
    font-size: 0.9375rem;
    font-weight: 500;
    transition: var(--transition-fast);
}

.nav-menu a:hover {
    color: var(--color-gray-900);
}

.nav-cta {
    background: var(--color-gray-900);
    color: var(--color-white) !important;
    padding: 10px 20px;
    border-radius: 6px;
    transition: var(--transition-base) !important;
}

.nav-cta:hover {
    background: var(--color-gray-700);
    color: var(--color-white) !important;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-gray-700);
    transition: var(--transition-base);
}

/* ========================================
   Buttons
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 28px;
    font-size: 0.9375rem;
    font-weight: 500;
    text-decoration: none;
    border-radius: 8px;
    transition: var(--transition-base);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--color-gray-900);
    color: var(--color-white);
}

.btn-primary:hover {
    background: var(--color-gray-700);
    transform: translateY(-1px);
}

.btn-secondary {
    background: var(--color-white);
    color: var(--color-gray-900);
    box-shadow: var(--shadow-md);
}

.btn-secondary:hover {
    background: var(--color-gray-50);
    transform: translateY(-1px);
    box-shadow: var(--shadow-lg);
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
    padding: 160px 0 100px;
    background: linear-gradient(180deg, var(--color-gray-50) 0%, var(--color-white) 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
}

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

.hero-content {
    max-width: 560px;
}

.hero-title {
    font-size: 3.25rem;
    font-weight: 700;
    line-height: 1.15;
    margin-bottom: 20px;
    letter-spacing: -0.03em;
    color: var(--color-gray-900);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-gray-600);
    margin-bottom: 32px;
    line-height: 1.6;
}

.hero-highlights {
    list-style: none;
    margin-bottom: 40px;
}

.hero-highlights li {
    position: relative;
    padding-left: 28px;
    margin-bottom: 12px;
    color: var(--color-gray-700);
    font-size: 1.0625rem;
}

.hero-highlights li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 10px;
    width: 8px;
    height: 8px;
    background: var(--color-primary-500);
    border-radius: 50%;
}

/* Hero Visual - Diagram */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.center-diagram {
    position: relative;
    width: 400px;
    height: 400px;
}

.diagram-center {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100px;
    height: 100px;
    background: var(--color-gray-900);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-white);
    font-weight: 700;
    font-size: 1.25rem;
    z-index: 10;
}

.diagram-orbit {
    position: absolute;
    top: 50%;
    left: 50%;
    border: 1px dashed var(--color-gray-200);
    border-radius: 50%;
}

.orbit-1 {
    width: 220px;
    height: 220px;
    margin-left: -110px;
    margin-top: -110px;
}

.orbit-2 {
    width: 300px;
    height: 300px;
    margin-left: -150px;
    margin-top: -150px;
}

.orbit-3 {
    width: 380px;
    height: 380px;
    margin-left: -190px;
    margin-top: -190px;
}

.orbit-item {
    position: absolute;
    padding: 10px 18px;
    background: var(--color-white);
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    box-shadow: var(--shadow-md);
    white-space: nowrap;
}

.orbit-item.innovation {
    top: 0;
    left: 50%;
    transform: translate(-50%, -50%);
    color: var(--color-innovation);
    border: 1px solid var(--color-innovation-light);
}

.orbit-item.control {
    bottom: 20%;
    right: 0;
    transform: translate(50%, 0);
    color: var(--color-control);
    border: 1px solid var(--color-control-light);
}

.orbit-item.design {
    bottom: 20%;
    left: 0;
    transform: translate(-50%, 0);
    color: var(--color-design);
    border: 1px solid var(--color-design-light);
}

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

.section-title {
    font-size: 2.25rem;
    font-weight: 600;
    margin-bottom: 20px;
    letter-spacing: -0.02em;
}

.section-description {
    font-size: 1.125rem;
    color: var(--color-gray-600);
    line-height: 1.7;
}

/* ========================================
   Overview Section
   ======================================== */
.overview {
    padding: var(--section-padding);
    background: var(--color-white);
}

.overview-visual {
    margin-top: 40px;
}

.lifecycle-flow {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 24px;
    flex-wrap: wrap;
}

.lifecycle-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
}

.lifecycle-icon {
    width: 80px;
    height: 80px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-base);
}

.lifecycle-icon svg {
    width: 36px;
    height: 36px;
}

.lifecycle-icon.innovation-icon {
    background: var(--color-innovation-light);
    color: var(--color-innovation);
}

.lifecycle-icon.control-icon {
    background: var(--color-control-light);
    color: var(--color-control);
}

.lifecycle-icon.design-icon {
    background: var(--color-design-light);
    color: var(--color-design);
}

.lifecycle-item span {
    font-weight: 500;
    color: var(--color-gray-700);
}

.lifecycle-arrow {
    color: var(--color-gray-300);
}

.lifecycle-arrow svg {
    width: 24px;
    height: 24px;
}

/* ========================================
   Centers Section
   ======================================== */
.centers {
    padding: var(--section-padding);
    background: var(--color-gray-50);
}

.center-card {
    display: grid;
    grid-template-columns: 1fr 400px;
    gap: 60px;
    align-items: center;
    background: var(--color-white);
    border-radius: 16px;
    padding: 60px;
    margin-bottom: 40px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-gray-100);
}

.center-card:last-child {
    margin-bottom: 0;
}

.center-card.reverse {
    grid-template-columns: 400px 1fr;
}

.center-card.reverse .center-card-visual {
    order: -1;
}

.center-badge {
    display: inline-block;
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 0.8125rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 16px;
}

.innovation-badge {
    background: var(--color-innovation-light);
    color: var(--color-innovation);
}

.control-badge {
    background: var(--color-control-light);
    color: var(--color-control);
}

.design-badge {
    background: var(--color-design-light);
    color: var(--color-design);
}

.center-title {
    font-size: 1.75rem;
    margin-bottom: 12px;
}

.center-tagline {
    font-size: 1.125rem;
    color: var(--color-gray-500);
    font-style: italic;
    margin-bottom: 20px;
}

.center-description {
    color: var(--color-gray-600);
    line-height: 1.7;
    margin-bottom: 28px;
}

.center-capabilities h4 {
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--color-gray-800);
    margin-bottom: 16px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.center-capabilities ul {
    list-style: none;
}

.center-capabilities li {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 10px 0;
    color: var(--color-gray-700);
    border-bottom: 1px solid var(--color-gray-100);
}

.center-capabilities li:last-child {
    border-bottom: none;
}

.center-capabilities li svg {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
    color: var(--color-primary-500);
    margin-top: 2px;
}

/* Center Card Visuals */
.center-card-visual {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 280px;
    border-radius: 12px;
}

.visual-icon {
    width: 160px;
    height: 160px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.visual-icon svg {
    width: 100%;
    height: 100%;
}

.innovation-visual {
    background: var(--color-innovation-light);
    color: var(--color-innovation);
}

.control-visual {
    background: var(--color-control-light);
    color: var(--color-control);
}

.design-visual {
    background: var(--color-design-light);
    color: var(--color-design);
}

/* ========================================
   Differentiators Section
   ======================================== */
.differentiators {
    padding: var(--section-padding);
    background: var(--color-white);
}

.diff-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
}

.diff-item {
    padding: 32px;
    background: var(--color-gray-50);
    border-radius: 12px;
    border: 1px solid var(--color-gray-100);
    transition: var(--transition-base);
}

.diff-item:hover {
    border-color: var(--color-gray-200);
    box-shadow: var(--shadow-md);
}

.diff-icon {
    width: 48px;
    height: 48px;
    background: var(--color-primary-50);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.diff-icon svg {
    width: 24px;
    height: 24px;
    color: var(--color-primary-600);
}

.diff-item h3 {
    font-size: 1.125rem;
    margin-bottom: 12px;
}

.diff-item p {
    color: var(--color-gray-600);
    font-size: 0.9375rem;
    line-height: 1.6;
}

/* ========================================
   Applications Section
   ======================================== */
.applications {
    padding: var(--section-padding);
    background: var(--color-gray-50);
}

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

.app-item {
    text-align: center;
    padding: 40px 24px;
    background: var(--color-white);
    border-radius: 12px;
    border: 1px solid var(--color-gray-100);
    transition: var(--transition-base);
}

.app-item:hover {
    border-color: var(--color-gray-200);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.app-icon {
    width: 56px;
    height: 56px;
    background: var(--color-gray-100);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    transition: var(--transition-base);
}

.app-item:hover .app-icon {
    background: var(--color-primary-50);
}

.app-icon svg {
    width: 28px;
    height: 28px;
    color: var(--color-gray-600);
    transition: var(--transition-base);
}

.app-item:hover .app-icon svg {
    color: var(--color-primary-600);
}

.app-item h3 {
    font-size: 1rem;
    font-weight: 500;
    line-height: 1.4;
}

/* ========================================
   CTA Section
   ======================================== */
.cta {
    padding: var(--section-padding);
    background: var(--color-gray-900);
}

.cta-content {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.cta-title {
    font-size: 2rem;
    color: var(--color-white);
    margin-bottom: 16px;
}

.cta-description {
    color: var(--color-gray-400);
    font-size: 1.125rem;
    margin-bottom: 32px;
    line-height: 1.7;
}

/* ========================================
   Footer
   ======================================== */
.footer {
    background: var(--color-gray-900);
    padding: 60px 0 30px;
    border-top: 1px solid var(--color-gray-800);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    padding-bottom: 40px;
    border-bottom: 1px solid var(--color-gray-800);
}

.footer-logo {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--color-white);
}

.footer-brand p {
    color: var(--color-gray-500);
    margin-top: 8px;
    font-size: 0.9375rem;
}

.footer-links {
    display: flex;
    gap: 32px;
}

.footer-links a {
    color: var(--color-gray-400);
    text-decoration: none;
    font-size: 0.9375rem;
    transition: var(--transition-fast);
}

.footer-links a:hover {
    color: var(--color-white);
}

.footer-bottom {
    padding-top: 30px;
    text-align: center;
}

.footer-bottom p {
    color: var(--color-gray-500);
    font-size: 0.875rem;
}

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

    .hero-content {
        max-width: 100%;
    }

    .hero-highlights {
        display: inline-block;
        text-align: left;
    }

    .hero-visual {
        order: -1;
        margin-bottom: 40px;
    }

    .center-diagram {
        width: 320px;
        height: 320px;
    }

    .diagram-center {
        width: 80px;
        height: 80px;
        font-size: 1rem;
    }

    .orbit-1 {
        width: 180px;
        height: 180px;
        margin-left: -90px;
        margin-top: -90px;
    }

    .orbit-2 {
        width: 240px;
        height: 240px;
        margin-left: -120px;
        margin-top: -120px;
    }

    .orbit-3 {
        width: 300px;
        height: 300px;
        margin-left: -150px;
        margin-top: -150px;
    }

    .center-card,
    .center-card.reverse {
        grid-template-columns: 1fr;
        padding: 40px;
    }

    .center-card.reverse .center-card-visual {
        order: 0;
    }

    .center-card-visual {
        min-height: 200px;
    }

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

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

@media (max-width: 768px) {
    :root {
        --section-padding: 70px 0;
    }

    .nav-menu {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: var(--color-white);
        flex-direction: column;
        padding: 20px 24px;
        gap: 16px;
        border-bottom: 1px solid var(--color-gray-100);
        box-shadow: var(--shadow-lg);
    }

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

    .nav-toggle {
        display: flex;
    }

    .nav-cta {
        width: 100%;
        text-align: center;
    }

    .hero {
        padding: 120px 0 60px;
        min-height: auto;
    }

    .hero-title {
        font-size: 2.25rem;
    }

    .hero-subtitle {
        font-size: 1.125rem;
    }

    .center-diagram {
        width: 280px;
        height: 280px;
    }

    .orbit-1 {
        width: 160px;
        height: 160px;
        margin-left: -80px;
        margin-top: -80px;
    }

    .orbit-2 {
        width: 210px;
        height: 210px;
        margin-left: -105px;
        margin-top: -105px;
    }

    .orbit-3 {
        width: 260px;
        height: 260px;
        margin-left: -130px;
        margin-top: -130px;
    }

    .orbit-item {
        padding: 8px 12px;
        font-size: 0.75rem;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .lifecycle-flow {
        gap: 16px;
    }

    .lifecycle-arrow {
        display: none;
    }

    .center-card {
        padding: 30px;
    }

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

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

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

    .footer-content {
        flex-direction: column;
        gap: 30px;
    }

    .footer-links {
        flex-wrap: wrap;
        gap: 20px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.875rem;
    }

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

    .center-diagram {
        width: 240px;
        height: 240px;
    }

    .diagram-center {
        width: 60px;
        height: 60px;
        font-size: 0.875rem;
    }

    .orbit-1 {
        width: 130px;
        height: 130px;
        margin-left: -65px;
        margin-top: -65px;
    }

    .orbit-2 {
        width: 180px;
        height: 180px;
        margin-left: -90px;
        margin-top: -90px;
    }

    .orbit-3 {
        width: 220px;
        height: 220px;
        margin-left: -110px;
        margin-top: -110px;
    }
}