/* EmbeddedOS.org - Main Stylesheet */

:root {
    --primary-color: #1a237e;
    --secondary-color: #3949ab;
    --accent-color: #00bcd4;
    --dark-bg: #0d1421;
    --light-bg: #f5f7fa;
    --text-dark: #2c3e50;
    --text-light: #ffffff;
    --gradient-primary: linear-gradient(135deg, #1a237e 0%, #3949ab 50%, #00bcd4 100%);
    --gradient-dark: linear-gradient(180deg, #0d1421 0%, #1a237e 100%);
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--light-bg);
}

/* Navigation */
.navbar {
    background: var(--gradient-dark);
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 2rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo img {
    height: 45px;
}

.logo-text {
    color: var(--text-light);
    font-size: 1.8rem;
    font-weight: 700;
    letter-spacing: 1px;
}

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

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    color: var(--text-light);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-color);
    transition: width 0.3s ease;
}

.nav-links a:hover::after {
    width: 100%;
}

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

/* Hero Section */
.hero {
    background: var(--gradient-primary);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 120px 2rem 60px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="50" cy="50" r="1" fill="rgba(255,255,255,0.1)"/></svg>');
    background-size: 50px 50px;
    animation: moveBackground 20s linear infinite;
}

@keyframes moveBackground {
    0% { transform: translateY(0); }
    100% { transform: translateY(-50px); }
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
}

.hero h1 {
    color: var(--text-light);
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.hero p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.4rem;
    margin-bottom: 2rem;
}

.hero-buttons {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    padding: 15px 35px;
    border-radius: 50px;
    font-size: 1.1rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    display: inline-block;
}

.btn-primary {
    background: var(--accent-color);
    color: var(--text-light);
    border: 2px solid var(--accent-color);
}

.btn-primary:hover {
    background: transparent;
    color: var(--accent-color);
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(0, 188, 212, 0.3);
}

.btn-secondary {
    background: transparent;
    color: var(--text-light);
    border: 2px solid var(--text-light);
}

.btn-secondary:hover {
    background: var(--text-light);
    color: var(--primary-color);
    transform: translateY(-3px);
}

/* Page Header */
.page-header {
    background: var(--gradient-primary);
    padding: 150px 2rem 80px;
    text-align: center;
}

.page-header h1 {
    color: var(--text-light);
    font-size: 3rem;
    margin-bottom: 1rem;
}

.page-header p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.3rem;
    max-width: 700px;
    margin: 0 auto;
}

/* Sections */
.section {
    padding: 80px 2rem;
}

.section-dark {
    background: var(--dark-bg);
    color: var(--text-light);
}

.section-light {
    background: var(--light-bg);
}

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

.section-title {
    text-align: center;
    margin-bottom: 3rem;
}

.section-title h2 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.section-dark .section-title h2 {
    color: var(--text-light);
}

.section-title p {
    color: #666;
    font-size: 1.2rem;
    max-width: 600px;
    margin: 0 auto;
}

.section-dark .section-title p {
    color: rgba(255, 255, 255, 0.7);
}

/* Cards Grid */
.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
}

.card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
}

.card-image {
    height: 200px;
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.card-image-placeholder {
    width: 80px;
    height: 80px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    color: white;
}

.card-content {
    padding: 2rem;
}

.card-content h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.4rem;
}

.card-content p {
    color: #666;
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.card-content a {
    color: var(--accent-color);
    text-decoration: none;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.card-content a:hover {
    text-decoration: underline;
}

/* Features Section */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.feature-item {
    text-align: center;
    padding: 2rem;
}

.feature-icon {
    width: 80px;
    height: 80px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 2rem;
    color: white;
}

.feature-item h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.feature-item p {
    color: #666;
}

/* Research Content */
.research-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.research-text h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.8rem;
}

.research-text p {
    color: #555;
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.research-text ul {
    list-style: none;
    margin-bottom: 1.5rem;
}

.research-text ul li {
    padding: 0.5rem 0;
    padding-left: 30px;
    position: relative;
    color: #555;
}

.research-text ul li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--accent-color);
    font-weight: bold;
}

.research-image {
    background: var(--gradient-primary);
    border-radius: 15px;
    height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.research-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.placeholder-img {
    color: white;
    font-size: 1.2rem;
    text-align: center;
    padding: 2rem;
}

/* Architecture Diagram */
.architecture-diagram {
    background: white;
    border-radius: 15px;
    padding: 3rem;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    margin: 3rem 0;
}

.diagram-layers {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.layer {
    background: var(--gradient-primary);
    color: white;
    padding: 1.5rem 2rem;
    border-radius: 10px;
    text-align: center;
    font-weight: 600;
    transition: transform 0.3s ease;
}

.layer:hover {
    transform: scale(1.02);
}

.layer-hardware { background: #1a237e; }
.layer-rtos { background: #283593; }
.layer-middleware { background: #3949ab; }
.layer-ai { background: #5c6bc0; }
.layer-security { background: #00bcd4; }
.layer-application { background: #26c6da; }

/* Positions/Jobs Section */
.positions-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.position-card {
    background: white;
    border-radius: 15px;
    padding: 2rem;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    border-left: 5px solid var(--accent-color);
    transition: transform 0.3s ease;
}

.position-card:hover {
    transform: translateX(10px);
}

.position-card h3 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.position-card .type {
    color: var(--accent-color);
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.position-card p {
    color: #666;
    margin-bottom: 1rem;
}

/* Table Styles */
.comparison-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.comparison-table th,
.comparison-table td {
    padding: 1.5rem;
    text-align: left;
    border-bottom: 1px solid #eee;
}

.comparison-table th {
    background: var(--primary-color);
    color: white;
    font-weight: 600;
}

.comparison-table tr:hover {
    background: #f8f9fa;
}

.comparison-table td:first-child {
    font-weight: 600;
    color: var(--primary-color);
}

/* Contact Form */
.contact-form {
    max-width: 600px;
    margin: 0 auto;
    background: white;
    padding: 3rem;
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
    font-weight: 500;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--accent-color);
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

/* Footer */
.footer {
    background: var(--dark-bg);
    color: var(--text-light);
    padding: 60px 2rem 30px;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
}

.footer-section h4 {
    color: var(--accent-color);
    margin-bottom: 1.5rem;
    font-size: 1.2rem;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 1rem;
}

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

.footer-section ul li {
    margin-bottom: 0.8rem;
}

.footer-section ul a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul a:hover {
    color: var(--accent-color);
}

.footer-bottom {
    max-width: 1200px;
    margin: 40px auto 0;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
    color: rgba(255, 255, 255, 0.5);
}

/* Responsive Design */
@media (max-width: 992px) {
    .research-content {
        grid-template-columns: 1fr;
    }

    .hero h1 {
        font-size: 2.5rem;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--dark-bg);
        flex-direction: column;
        padding: 2rem;
        gap: 1rem;
    }

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

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

    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1.1rem;
    }

    .section {
        padding: 60px 1rem;
    }

    .page-header {
        padding: 120px 1rem 60px;
    }

    .page-header h1 {
        font-size: 2rem;
    }

    .comparison-table {
        display: block;
        overflow-x: auto;
    }
}

/* Utility Classes */
.text-center { text-align: center; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.mb-3 { margin-bottom: 3rem; }
.mt-2 { margin-top: 2rem; }
.mt-3 { margin-top: 3rem; }

/* Animation Classes */
.fade-in {
    animation: fadeIn 0.8s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Icon placeholders */
.icon-neural::before { content: '🧠'; }
.icon-security::before { content: '🔒'; }
.icon-chip::before { content: '💻'; }
.icon-car::before { content: '🚗'; }
.icon-drone::before { content: '🚁'; }
.icon-home::before { content: '🏠'; }
.icon-industry::before { content: '🏭'; }
.icon-ai::before { content: '🤖'; }
.icon-doc::before { content: '📄'; }
.icon-education::before { content: '🎓'; }
.icon-research::before { content: '🔬'; }
.icon-patent::before { content: '📜'; }
.icon-career::before { content: '💼'; }