/* ============================================
   Open Deller - Main Stylesheet
   Modern, Clean, Professional Design
   ============================================ */

/* ============================================
   1. CSS Variables & Reset
   ============================================ */

:root {
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --primary-light: #3b82f6;
    --secondary-color: #0ea5e9;
    --accent-color: #8b5cf6;
    --dark-bg: #0f172a;
    --dark-bg-light: #1e293b;
    --light-bg: #f8fafc;
    --text-dark: #0f172a;
    --text-light: #64748b;
    --text-white: #ffffff;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --max-width: 1360px;
    --header-height: 80px;
}

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

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background: var(--text-white);
    overflow-x: hidden;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: inherit;
    text-decoration: none;
    transition: var(--transition-fast);
}

ul {
    list-style: none;
}

/* ============================================
   2. Typography
   ============================================ */

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
}

h2 {
    font-size: clamp(2rem, 4vw, 3rem);
}

h3 {
    font-size: clamp(1.5rem, 3vw, 2rem);
}

p {
    margin-bottom: 1rem;
}

.lead {
    font-size: 1.25rem;
    color: var(--text-light);
    line-height: 1.8;
}

/* ============================================
   3. Layout Utilities
   ============================================ */

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 3vw;
}

.section-padding {
    padding: 6rem 0;
}

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

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

.section-header {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 4rem;
}

.section-title {
    color: inherit;
    margin-bottom: 1rem;
}

.section-subtitle {
    font-size: 1.25rem;
    color: var(--text-light);
}

.bg-dark .section-subtitle {
    color: rgba(255, 255, 255, 0.7);
}

.label {
    display: inline-block;
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

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

/* ============================================
   4. Buttons
   ============================================ */

.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    text-align: center;
    border-radius: 50px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-normal);
    white-space: nowrap;
}

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

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

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

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

.btn-large {
    padding: 1.125rem 2.5rem;
    font-size: 1.125rem;
}

.btn-full {
    width: 100%;
}

/* ============================================
   5. Header
   ============================================ */

.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: var(--transition-normal);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--header-height);
}

.logo-img {
    height: 40px;
    width: auto;
}

.main-nav ul {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.main-nav a {
    font-weight: 500;
    position: relative;
}

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width var(--transition-fast);
}

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

.header-actions {
    display: flex;
    gap: 1rem;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 2px;
    background: var(--text-dark);
    transition: var(--transition-fast);
}

/* ============================================
   6. Hero Section
   ============================================ */

.hero-section {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding-top: var(--header-height);
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    opacity: 0.05;
    z-index: -1;
}

.hero-background::before {
    content: '';
    position: absolute;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, var(--primary-color) 0%, transparent 70%);
    top: -300px;
    right: -300px;
    opacity: 0.1;
    animation: float 20s ease-in-out infinite;
}

.hero-background::after {
    content: '';
    position: absolute;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, var(--accent-color) 0%, transparent 70%);
    bottom: -200px;
    left: -200px;
    opacity: 0.1;
    animation: float 15s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% {
        transform: translate(0, 0);
    }
    50% {
        transform: translate(50px, 50px);
    }
}

.hero-content {
    text-align: center;
    max-width: 900px;
    margin: 0 auto;
    animation: fadeInUp 1s ease;
}

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

.hero-title {
    margin-bottom: 1.5rem;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-light);
    max-width: 700px;
    margin: 0 auto 2.5rem;
    line-height: 1.8;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-light);
    font-size: 0.875rem;
    animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
    0%, 100% {
        transform: translate(-50%, 0);
    }
    50% {
        transform: translate(-50%, 10px);
    }
}

/* ============================================
   7. Platform Section
   ============================================ */

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

.platform-card {
    padding: 2rem;
    background: var(--text-white);
    border-radius: 16px;
    border: 1px solid var(--border-color);
    transition: all var(--transition-normal);
}

.platform-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.card-icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-light), var(--secondary-color));
    border-radius: 12px;
    margin-bottom: 1.5rem;
    color: var(--text-white);
}

.platform-card h3 {
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.platform-card p {
    color: var(--text-light);
    margin-bottom: 0;
}

/* ============================================
   8. Solutions Section
   ============================================ */

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 3rem;
}

.solution-item {
    position: relative;
    padding: 2.5rem 2rem;
    background: var(--dark-bg-light);
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all var(--transition-normal);
}

.solution-item:hover {
    transform: translateY(-8px);
    border-color: var(--primary-color);
    box-shadow: 0 10px 40px rgba(37, 99, 235, 0.2);
}

.solution-number {
    font-size: 3rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.solution-item h3 {
    margin-bottom: 1rem;
    color: var(--text-white);
}

.solution-item p {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 1.5rem;
}

.feature-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.feature-list li {
    color: rgba(255, 255, 255, 0.6);
    padding-left: 1.5rem;
    position: relative;
}

.feature-list li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: 700;
}

/* ============================================
   9. Technology Section
   ============================================ */

.tech-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.tech-text h2 {
    margin-bottom: 1.5rem;
}

.tech-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
    margin: 2rem 0;
}

.stat-item {
    text-align: center;
    padding: 1.5rem;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.1), rgba(139, 92, 246, 0.1));
    border-radius: 12px;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-light);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.tech-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.tech-list li {
    padding-left: 1.5rem;
    position: relative;
    color: var(--text-light);
}

.tech-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: 700;
}

.tech-visual {
    position: relative;
}

.tech-diagram {
    background: var(--light-bg);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
}

.tech-diagram img {
    width: 100%;
    height: auto;
    border-radius: 8px;
}

/* ============================================
   10. About Section
   ============================================ */

.about-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-text h2 {
    margin-bottom: 1.5rem;
}

.about-text p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 3rem;
}

.stat-box {
    text-align: center;
    padding: 2rem 1rem;
    background: var(--text-white);
    border-radius: 12px;
    box-shadow: var(--shadow-md);
}

.stat-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-desc {
    font-size: 0.875rem;
    color: var(--text-light);
}

.about-image {
    position: relative;
}

.about-image img {
    width: 100%;
    height: auto;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
}

/* ============================================
   11. Contact Section
   ============================================ */

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact-info h2 {
    margin-bottom: 1rem;
}

.info-items {
    margin-top: 3rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.info-item {
    display: flex;
    gap: 1.5rem;
}

.info-item svg {
    flex-shrink: 0;
    color: var(--primary-color);
}

.info-item h4 {
    margin-bottom: 0.5rem;
    font-size: 1rem;
}

.info-item p {
    color: var(--text-light);
    margin-bottom: 0;
}

.contact-form {
    background: var(--light-bg);
    padding: 3rem;
    border-radius: 16px;
}

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

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group textarea {
    resize: vertical;
}

/* ============================================
   12. Footer
   ============================================ */

.site-footer {
    background: var(--dark-bg);
    color: var(--text-white);
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr repeat(4, 1fr);
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-logo {
    margin-bottom: 1rem;
}

.footer-logo img {
    height: 36px;
    width: auto;
}

.footer-column p {
    color: rgba(255, 255, 255, 0.6);
    margin-bottom: 1.5rem;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    transition: var(--transition-fast);
}

.social-links a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-column h4 {
    margin-bottom: 1rem;
    font-size: 1rem;
}

.footer-column ul {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.footer-column a {
    color: rgba(255, 255, 255, 0.6);
    transition: var(--transition-fast);
}

.footer-column a:hover {
    color: var(--text-white);
    padding-left: 5px;
}

.footer-bottom {
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
    color: rgba(255, 255, 255, 0.4);
}

/* ============================================
   13. Responsive Design
   ============================================ */

@media (max-width: 1024px) {
    .tech-content,
    .about-content,
    .contact-wrapper {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
    
    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 70px;
    }
    
    .main-nav {
        position: fixed;
        top: var(--header-height);
        left: -100%;
        width: 100%;
        height: calc(100vh - var(--header-height));
        background: var(--text-white);
        transition: left var(--transition-normal);
        padding: 2rem;
        box-shadow: var(--shadow-lg);
    }
    
    .main-nav.active {
        left: 0;
    }
    
    .main-nav ul {
        flex-direction: column;
        gap: 1.5rem;
        align-items: flex-start;
    }
    
    .header-actions {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(7px, 7px);
    }
    
    .mobile-menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -7px);
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .hero-actions .btn {
        width: 100%;
        max-width: 300px;
    }
    
    .platform-grid,
    .solutions-grid {
        grid-template-columns: 1fr;
    }
    
    .tech-stats,
    .about-stats {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .section-padding {
        padding: 4rem 0;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 14px;
    }
    
    .container {
        padding: 0 5vw;
    }
    
    .btn {
        padding: 0.75rem 1.5rem;
    }
    
    .platform-card,
    .solution-item {
        padding: 1.5rem;
    }
    
    .contact-form {
        padding: 2rem;
    }
}

/* ============================================
   14. Animations & Effects
   ============================================ */

.fade-in {
    opacity: 0;
    animation: fadeIn 0.6s ease forwards;
}

@keyframes fadeIn {
    to {
        opacity: 1;
    }
}

.slide-up {
    opacity: 0;
    transform: translateY(30px);
    animation: slideUp 0.6s ease forwards;
}

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

/* Smooth scroll offset for fixed header */
section {
    scroll-margin-top: var(--header-height);
}

/* Loading state */
.loading {
    pointer-events: none;
    opacity: 0.6;
}