/* ==========================================================================
   QVIT OS - Main Design System & Stylesheet
   ========================================================================== */

/* Design Tokens & Variables */
:root {
    --bg-main: #060913;
    --bg-card: rgba(13, 20, 38, 0.65);
    --bg-header: rgba(6, 9, 19, 0.8);
    --bg-terminal: #070a14;
    
    --primary: #00f0ff;      /* Quantum Neon Cyan */
    --primary-rgb: 0, 240, 255;
    --secondary: #a855f7;    /* Tech Purple */
    --secondary-rgb: 168, 85, 247;
    
    --text-main: #e2e8f0;
    --text-muted: #94a3b8;
    --text-white: #ffffff;
    
    --border-color: rgba(255, 255, 255, 0.08);
    --border-glow: rgba(0, 240, 255, 0.15);
    --border-glow-hover: rgba(0, 240, 255, 0.35);
    
    --font-sans: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    --transition-fast: 0.2s ease;
    --transition-medium: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    --border-radius: 12px;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
    background-color: var(--bg-main);
    color: var(--text-main);
    font-family: var(--font-sans);
    -webkit-font-smoothing: antialiased;
    -webkit-tap-highlight-color: transparent;
}

body {
    overflow-x: hidden;
    line-height: 1.6;
    text-align: justify;
    -webkit-touch-callout: none;
}

.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 2rem;
}

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

button, input {
    font-family: inherit;
}

code {
    font-family: var(--font-mono);
}

/* Text Accents & Utility */
.accent-text {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 700;
}

/* Grid Background */
.grid-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-image: 
        radial-gradient(circle at 50% 30%, rgba(var(--primary-rgb), 0.08) 0%, transparent 60%),
        radial-gradient(circle at 10% 20%, rgba(var(--secondary-rgb), 0.05) 0%, transparent 40%),
        linear-gradient(rgba(255, 255, 255, 0.007) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.007) 1px, transparent 1px);
    background-size: 100% 100%, 100% 100%, 40px 40px, 40px 40px;
    z-index: 0;
    pointer-events: none;
}

/* Section Header Base */
.section-header {
    text-align: center;
    margin-bottom: 4rem;
    position: relative;
    z-index: 1;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: -0.025em;
    color: var(--text-white);
    margin-bottom: 1rem;
}

.section-header .divider {
    height: 4px;
    width: 60px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    margin: 0 auto 1.25rem;
    border-radius: 2px;
}

.section-header .section-subtitle {
    font-size: 1.125rem;
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto;
}

.subsection-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 2rem;
    text-align: center;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.8rem 1.8rem;
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: 8px;
    border: 1px solid transparent;
    cursor: pointer;
    transition: var(--transition-fast);
    min-height: 44px;
    min-width: 44px;
    -webkit-user-select: none;
    user-select: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), #00c8ff);
    color: #040814;
    box-shadow: 0 4px 20px rgba(0, 240, 255, 0.25);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(0, 240, 255, 0.4);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.03);
    border-color: var(--border-color);
    color: var(--text-main);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(var(--primary-rgb), 0.4);
    transform: translateY(-2px);
}

.btn-secondary:active {
    transform: translateY(0);
}

/* Photo Placeholders Styling */
.photo-placeholder-wrapper {
    position: relative;
    border-radius: var(--border-radius);
    padding: 3px;
    background: linear-gradient(135deg, var(--border-color), rgba(255,255,255,0.02));
    transition: var(--transition-medium);
    margin-top: 1.5rem;
}

.photo-placeholder-wrapper::before {
    content: attr(data-label);
    position: absolute;
    top: -12px;
    left: 20px;
    background: #0f172a;
    padding: 2px 10px;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--primary);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    z-index: 10;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.photo-placeholder-wrapper:hover {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    box-shadow: 0 0 25px rgba(var(--primary-rgb), 0.15);
}

.photo-placeholder {
    position: relative;
    width: 100%;
    height: auto;
    background: #0b0f19;
    border-radius: calc(var(--border-radius) - 2px);
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.photo-placeholder .user-photo {
    width: 100%;
    height: auto;
    object-fit: contain;
    object-position: center;
    display: block;
    background: transparent;
}

.placeholder-fallback {
    display: none; /* Controlled via JS & onerror */
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem 1.5rem;
    text-align: center;
    width: 100%;
    color: var(--text-muted);
}

.placeholder-icon {
    width: 48px;
    height: 48px;
    margin-bottom: 1rem;
    stroke: rgba(var(--primary-rgb), 0.6);
}

.placeholder-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-white);
    margin-bottom: 0.5rem;
}

.placeholder-subtitle {
    font-size: 0.85rem;
    max-width: 350px;
    line-height: 1.5;
}

.placeholder-subtitle code {
    background: rgba(255, 255, 255, 0.06);
    padding: 2px 6px;
    border-radius: 4px;
    color: var(--secondary);
    font-size: 0.8rem;
}

/* Main Header */
.main-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: var(--bg-header);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition-fast);
}

.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 80px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    font-size: 1.4rem;
    color: var(--text-white);
    letter-spacing: -0.03em;
}

.logo-icon {
    width: 36px;
    height: 36px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 900;
    overflow: hidden;
}

.logo-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

/* Navigation Menu - Desktop Base */
.nav-menu {
    display: flex;
    flex: 1;
    justify-content: center;
}

.nav-menu ul {
    display: flex;
    list-style: none;
    gap: 1.8rem;
}

.nav-link {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-muted);
    padding: 0.5rem 0.75rem;
    border-radius: 4px;
    transition: var(--transition-fast);
    display: inline-block;
    min-height: 44px;
    display: flex;
    align-items: center;
}

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

.btn-download-nav {
    background: rgba(0, 240, 255, 0.1);
    color: var(--primary);
    border: 1px solid rgba(0, 240, 255, 0.3);
    padding: 0.4rem 1rem;
    border-radius: 6px;
    transition: var(--transition-fast);
    min-height: 40px;
}

.btn-download-nav:hover {
    background: var(--primary);
    color: #040814;
    border-color: var(--primary);
}

/* VIT-AP University Logo in Header */
.vitap-logo-link {
    display: flex;
    align-items: center;
    margin-left: 1.5rem;
    flex-shrink: 0;
    opacity: 0.9;
    transition: var(--transition-fast);
}

.vitap-logo-link:hover {
    opacity: 1;
    filter: drop-shadow(0 0 8px rgba(0, 240, 255, 0.4));
}

.vitap-logo-img {
    height: 38px;
    width: auto;
    object-fit: contain;
    filter: brightness(0) invert(1);
}

.mobile-nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 24px;
    height: 18px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 8px;
    margin-right: -8px;
    min-height: 44px;
    min-width: 44px;
    -webkit-user-select: none;
    user-select: none;
}

.mobile-nav-toggle span {
    height: 2px;
    width: 100%;
    background-color: var(--text-white);
    border-radius: 2px;
    transition: var(--transition-fast);
}

/* Hero Section */
.hero-section {
    position: relative;
    padding-top: 160px;
    padding-bottom: 80px;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero-container {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content {
    max-width: 620px;
}

.badge {
    display: inline-block;
    padding: 4px 12px;
    background: rgba(168, 85, 247, 0.1);
    border: 1px solid rgba(168, 85, 247, 0.3);
    color: #c084fc;
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: 50px;
    margin-bottom: 1.5rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.03em;
    color: var(--text-white);
    margin-bottom: 1rem;
}

.hero-tagline {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 1.5rem;
    letter-spacing: -0.01em;
}

.hero-description {
    font-size: 1.125rem;
    color: var(--text-muted);
    margin-bottom: 2.5rem;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 1.25rem;
}

#placeholder-desktop {
}

/* About Section */
.about-section {
    position: relative;
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
}

.about-grid {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 3rem;
    margin-bottom: 4rem;
}

.about-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.about-card.text-card {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 1.5rem;
}

.highlight-text {
    font-size: 1.2rem;
    font-weight: 500;
    color: var(--text-white);
    line-height: 1.6;
}

.tags-container {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 1rem;
}

.tag {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    padding: 5px 12px;
    border-radius: 6px;
    font-size: 0.8rem;
    font-weight: 500;
}

.specs-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.8rem;
}

.specs-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.specs-list li {
    display: flex;
    justify-content: space-between;
    font-size: 0.95rem;
    border-bottom: 1px dashed rgba(255, 255, 255, 0.05);
    padding-bottom: 0.8rem;
}

.specs-list li:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.spec-label {
    color: var(--text-muted);
}

.spec-value {
    color: var(--primary);
    font-weight: 600;
}

#placeholder-boot {
    min-height: 400px;
}

/* Why Section */
.why-section {
    padding: 100px 0;
    background: radial-gradient(circle at 50% 80%, rgba(var(--secondary-rgb), 0.04) 0%, transparent 60%);
    border-top: 1px solid var(--border-color);
}

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

.why-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2.2rem;
    transition: var(--transition-medium);
}

.why-card:hover {
    transform: translateY(-5px);
    border-color: rgba(var(--primary-rgb), 0.3);
    box-shadow: 0 10px 30px rgba(var(--primary-rgb), 0.05);
}

.card-icon {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    background: rgba(0, 240, 255, 0.08);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.card-icon svg {
    width: 24px;
    height: 24px;
}

.why-card h3 {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 0.8rem;
}

.why-card p {
    font-size: 0.925rem;
    color: var(--text-muted);
    line-height: 1.6;
}

/* Core Features & Advantages Table */
.features-section {
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-bottom: 5rem;
}

.feature-box {
    background: #090e1a;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2rem;
    transition: var(--transition-medium);
}

.feature-box:hover {
    background: var(--bg-card);
    border-color: rgba(var(--secondary-rgb), 0.3);
    box-shadow: 0 10px 30px rgba(var(--secondary-rgb), 0.05);
}

.feature-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 1rem;
}

.feature-num {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--secondary);
    background: rgba(168, 85, 247, 0.1);
    padding: 2px 8px;
    border-radius: 4px;
}

.feature-box h3 {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--text-white);
}

.feature-box p {
    font-size: 0.9rem;
    color: var(--text-muted);
    line-height: 1.5;
}

.advantages-container {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 3rem 2.5rem;
    margin-top: 4rem;
}

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

.comparison-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    min-width: 600px;
}

.comparison-table th, .comparison-table td {
    padding: 1.2rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.comparison-table th {
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--text-white);
    letter-spacing: 0.05em;
    text-transform: uppercase;
    border-bottom: 2px solid var(--border-color);
}

.comparison-table td {
    font-size: 0.95rem;
}

.comparison-table td strong {
    color: var(--text-white);
}

.comparison-table .highlight-col {
    background: rgba(0, 240, 255, 0.02);
    color: var(--text-white);
    border-left: 1px dashed rgba(0, 240, 255, 0.15);
    border-right: 1px dashed rgba(0, 240, 255, 0.15);
}

.comparison-table th.highlight-col {
    color: var(--primary);
    background: rgba(0, 240, 255, 0.05);
}

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

/* Quantum Frameworks Section */
.frameworks-section {
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
    background: radial-gradient(circle at 10% 20%, rgba(var(--primary-rgb), 0.03) 0%, transparent 55%);
}

.frameworks-container {
    display: flex;
    flex-direction: column;
    gap: 2.5rem;
}

.framework-tabs {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 10px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 1.25rem;
}

.tab-btn {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    padding: 8px 20px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    transition: var(--transition-fast);
}

.tab-btn:hover {
    color: var(--text-white);
    border-color: rgba(255, 255, 255, 0.2);
}

.tab-btn.active {
    background: rgba(0, 240, 255, 0.1);
    color: var(--primary);
    border-color: var(--primary);
}

.tab-content-wrapper {
    position: relative;
}

.tab-panel {
    display: none;
    animation: fadeIn 0.4s ease forwards;
}

.tab-panel.active {
    display: block;
}

.panel-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.panel-info {
    max-width: 550px;
}

.framework-logo {
    display: inline-block;
    padding: 4px 12px;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    border-radius: 4px;
    margin-bottom: 1.25rem;
}

.qiskit-logo { background: #6929c4; color: #fff; }
.pennylane-logo { background: #1976d2; color: #fff; }
.tfq-logo { background: #ff6f00; color: #fff; }
.cirq-logo { background: #34a853; color: #fff; }
.openfermion-logo { background: #00838f; color: #fff; }
.stack-logo { background: #607d8b; color: #fff; }

.panel-info h3 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 1rem;
}

.framework-desc {
    font-size: 1rem;
    color: var(--text-muted);
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.panel-info h4 {
    font-size: 0.95rem;
    color: var(--text-white);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.75rem;
}

.framework-usecases {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.framework-usecases li {
    position: relative;
    padding-left: 20px;
    font-size: 0.95rem;
    color: var(--text-muted);
}

.framework-usecases li::before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--primary);
    font-weight: bold;
}

.panel-code {
    background: var(--bg-terminal);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.4);
}

.code-header {
    background: rgba(255,255,255,0.02);
    border-bottom: 1px solid var(--border-color);
    padding: 10px 18px;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-muted);
}

.panel-code pre {
    padding: 1.5rem;
    margin: 0;
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    line-height: 1.5;
}

/* Syntax Highlighting */
.keyword { color: #f43f5e; }
.comment { color: #64748b; font-style: italic; }
.number { color: #38bdf8; }
.string { color: #34d399; }
.function { color: #fbbf24; }

/* Command Center (Terminal Sim) */
.command-center-section {
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
}

.cli-container {
    display: grid;
    grid-template-columns: 0.9fr 1.1fr;
    gap: 3rem;
    margin-bottom: 4rem;
}

.cli-docs {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2.2rem;
}

.cli-docs h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 0.5rem;
}

.docs-intro {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 1.8rem;
}

.command-items {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.cmd-item {
    background: rgba(255, 255, 255, 0.01);
    border: 1px solid var(--border-color);
    padding: 12px 16px;
    border-radius: 6px;
    display: flex;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
    transition: var(--transition-fast);
}

.cmd-item:hover {
    border-color: rgba(var(--primary-rgb), 0.4);
    background: rgba(0, 240, 255, 0.02);
}

.cmd-syntax {
    font-family: var(--font-mono);
    font-size: 0.9rem;
    font-weight: 700;
    color: var(--primary);
}

.cmd-desc {
    font-size: 0.825rem;
    color: var(--text-muted);
}

.cli-terminal {
    background: var(--bg-terminal);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    box-shadow: 0 20px 40px rgba(0,0,0,0.5);
    height: 480px;
}

.terminal-header {
    background: #0f1322;
    border-bottom: 1px solid var(--border-color);
    padding: 12px 18px;
    display: flex;
    align-items: center;
    position: relative;
}

.window-controls {
    display: flex;
    gap: 6px;
}

.dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    display: inline-block;
}

.dot.close { background: #ef4444; }
.dot.minimize { background: #f59e0b; }
.dot.maximize { background: #10b981; }

.window-title {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-muted);
}

.terminal-body {
    padding: 1.5rem;
    flex: 1;
    overflow-y: auto;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: #e2e8f0;
    line-height: 1.6;
}

.terminal-line {
    word-break: break-all;
    margin-bottom: 6px;
    white-space: pre-wrap;
}

.terminal-line.output-info { color: #60a5fa; }
.terminal-line.output-success { color: #34d399; }
.terminal-line.output-error { color: #f87171; }
.terminal-line.output-warning { color: #fbbf24; }

.terminal-interactive-line {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-top: 10px;
}

.terminal-prompt {
    color: #a78bfa;
    font-weight: bold;
    white-space: nowrap;
}

#terminal-input {
    background: transparent;
    border: none;
    outline: none;
    color: #ffffff;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    flex: 1;
    width: 100%;
}

#placeholder-terminal {
    min-height: 350px;
}

/* Target Users Grid */
.users-section {
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
}

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

.user-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2.2rem;
    text-align: center;
    transition: var(--transition-fast);
}

.user-card:hover {
    border-color: rgba(var(--secondary-rgb), 0.3);
    transform: translateY(-4px);
}

.user-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    display: block;
}

.user-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 0.8rem;
}

.user-card p {
    font-size: 0.9rem;
    color: var(--text-muted);
    line-height: 1.5;
}

/* System Requirements & Hardware */
.requirements-section {
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
    background: radial-gradient(circle at 90% 80%, rgba(var(--primary-rgb), 0.03) 0%, transparent 60%);
}

.req-tabs {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 2.5rem;
}

.req-tab-btn {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    padding: 10px 24px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 600;
    transition: var(--transition-fast);
}

.req-tab-btn:hover {
    color: var(--text-white);
    border-color: rgba(255, 255, 255, 0.15);
}

.req-tab-btn.active {
    background: rgba(168, 85, 247, 0.12);
    color: #d8b4fe;
    border-color: var(--secondary);
}

.req-content-wrapper {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1rem;
    margin-bottom: 3rem;
}

.req-panel {
    display: none;
    animation: fadeIn 0.4s ease forwards;
}

.req-panel.active {
    display: block;
}

.req-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
}

.req-table th, .req-table td {
    padding: 1.2rem;
    border-bottom: 1px solid rgba(255,255,255,0.05);
}

.req-table th {
    color: var(--text-white);
    font-weight: 700;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border-bottom: 2px solid var(--border-color);
}

.req-table td {
    font-size: 0.95rem;
}

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

.hw-compatibility-box {
    background: rgba(255,255,255,0.01);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2.5rem;
}

.hw-compatibility-box h4 {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 1.5rem;
    text-align: center;
}

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

.compat-item h5 {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 0.5rem;
}

.compat-item p {
    font-size: 0.875rem;
    color: var(--text-muted);
    line-height: 1.5;
}

/* Download Section */
.download-section {
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 3rem;
    margin-bottom: 3rem;
    max-width: 960px;
    margin-left: auto;
    margin-right: auto;
}

.download-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 3rem 2.5rem;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: var(--transition-medium);
}

.download-card:hover {
    border-color: rgba(var(--primary-rgb), 0.3);
    box-shadow: 0 15px 35px rgba(var(--primary-rgb), 0.05);
}

.download-icon {
    width: 64px;
    height: 64px;
    border-radius: 12px;
    background: rgba(0, 240, 255, 0.05);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.download-icon svg {
    width: 32px;
    height: 32px;
}

.download-card h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 0.5rem;
}

.version-badge {
    background: rgba(168, 85, 247, 0.15);
    color: #d8b4fe;
    font-size: 0.75rem;
    font-weight: 700;
    padding: 4px 10px;
    border-radius: 4px;
    margin-bottom: 1.5rem;
    font-family: var(--font-mono);
}

.download-card p {
    font-size: 0.95rem;
    color: var(--text-muted);
    line-height: 1.6;
    margin-bottom: 2rem;
    flex: 1;
}

.download-meta {
    display: flex;
    gap: 1.5rem;
    font-size: 0.85rem;
    color: var(--text-muted);
    border-top: 1px solid rgba(255,255,255,0.05);
    padding-top: 1.25rem;
    margin-bottom: 1.5rem;
    width: 100%;
    justify-content: center;
}

.download-meta strong {
    color: var(--text-white);
}

.download-card .btn {
    width: 100%;
}

.documentation-card {
    background: #090e1a;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2.2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 2rem;
}

.doc-info h3 {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 0.4rem;
}

.doc-info p {
    font-size: 0.9rem;
    color: var(--text-muted);
    max-width: 600px;
}

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

.doc-btn {
    padding: 0.6rem 1.2rem;
    font-size: 0.875rem;
}

/* FAQ Section */
.faqs-section {
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
    background: radial-gradient(circle at 10% 80%, rgba(var(--secondary-rgb), 0.03) 0%, transparent 55%);
}

.faqs-list {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.faq-item {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
}

.faq-question {
    width: 100%;
    background: transparent;
    border: none;
    outline: none;
    padding: 1.5rem;
    text-align: left;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-white);
    cursor: pointer;
    transition: var(--transition-fast);
}

.faq-question:hover {
    color: var(--primary);
}

.faq-toggle-icon {
    font-size: 1.5rem;
    font-family: var(--font-mono);
    color: var(--primary);
    transition: transform var(--transition-fast);
}

.faq-item.open .faq-toggle-icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
}

.faq-answer p {
    padding: 0 1.5rem 1.5rem 1.5rem;
    font-size: 0.95rem;
    color: var(--text-muted);
    line-height: 1.6;
}

/* Authors & Initiative */
.authors-section {
    padding: 100px 0;
    border-top: 1px solid var(--border-color);
}

.project-info-block {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 3rem;
    margin-bottom: 4rem;
}

.institutions {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.inst-logo {
    border-left: 3px solid var(--primary);
    padding-left: 1.25rem;
}

.inst-title {
    font-size: 1.3rem;
    font-weight: 800;
    color: var(--text-white);
}

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

.mission-quote blockquote {
    font-size: 1.4rem;
    font-style: italic;
    font-weight: 500;
    color: var(--text-white);
    line-height: 1.5;
    position: relative;
}

.mission-quote blockquote::before {
    content: "“";
    font-size: 4rem;
    position: absolute;
    top: -40px;
    left: -20px;
    color: rgba(var(--primary-rgb), 0.15);
    font-family: serif;
}

/* Development Showcase Section */
.showcase-container {
    margin: 3rem 0;
    border-radius: var(--border-radius);
    overflow: hidden;
    border: 1px solid var(--border-color);
    background: var(--bg-card);
    transition: all var(--transition-fast);
}

.showcase-container:hover {
    border-color: rgba(var(--primary-rgb), 0.3);
    box-shadow: 0 0 30px rgba(var(--primary-rgb), 0.1);
}

.showcase-image {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: fill;
}

.showcase-caption {
    padding: 1.5rem;
    text-align: center;
    background: rgba(6, 9, 19, 0.5);
    border-top: 1px solid var(--border-color);
}

.showcase-caption p {
    font-size: 1rem;
    color: var(--text-main);
    margin: 0;
}

.development-story {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.development-story p {
    font-size: 1rem;
    line-height: 1.7;
    color: var(--text-main);
    margin: 0;
    text-align: justify;
}

.development-story p strong {
    color: var(--primary);
    font-weight: 700;
}

.development-story code {
    background: rgba(var(--primary-rgb), 0.1);
    color: var(--primary);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.9em;
}

.authors-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
}

.author-card {
    background: #090e1a;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2rem 1.5rem;
    text-align: center;
    transition: var(--transition-fast);
}

.author-card:hover {
    border-color: rgba(var(--primary-rgb), 0.2);
    background: var(--bg-card);
}

.author-avatar {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: linear-gradient(135deg, rgba(var(--primary-rgb), 0.1) 0%, rgba(var(--secondary-rgb), 0.1) 100%);
    border: 1px solid var(--border-color);
    color: var(--primary);
    font-size: 1.5rem;
    font-weight: 800;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.25rem;
}

.author-card h4 {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: 0.25rem;
}

.author-role {
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* Main Footer */
.main-footer {
    border-top: 1px solid var(--border-color);
    padding: 3rem 0;
    background: #04070d;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 2rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 800;
    color: var(--text-white);
}

.footer-logo .logo-icon {
    width: 28px;
    height: 28px;
    border-radius: 6px;
    font-size: 1rem;
}

.copyright {
    font-size: 0.85rem;
    color: var(--text-muted);
    max-width: 650px;
    text-align: right;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Media Queries (Responsive Design) */

/* Tablet: 1025px - 1024px */
@media (max-width: 1024px) {
    .container {
        padding: 0 1.5rem;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        gap: 3rem;
        text-align: center;
    }
    
    .hero-content {
        max-width: 100%;
        margin: 0 auto;
    }
    
    .hero-content h1 {
        font-size: 3rem;
    }
    
    .hero-buttons {
        justify-content: center;
        flex-wrap: wrap;
    }
    
    .about-grid, .panel-layout, .cli-container, .project-info-block {
        grid-template-columns: 1fr;
        gap: 2.5rem;
    }
    
    .comparison-grid, .features-grid, .users-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .authors-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .copyright {
        text-align: left;
    }
    
    .header-container {
        height: 70px;
    }
    
    .vitap-logo-link {
        margin-left: 1rem;
    }
    
    .vitap-logo-img {
        height: 32px;
    }
}

/* Mobile Tablet: 769px - 1023px */
@media (max-width: 1023px) {
    .nav-menu ul {
        gap: 1.2rem;
    }
    
    .nav-link {
        font-size: 0.85rem;
    }
}

/* Mobile: 481px - 768px */
@media (max-width: 768px) {
    html {
        font-size: 14px;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    /* Header & Navigation */
    .header-container {
        height: 60px;
    }
    
    .logo {
        gap: 8px;
        font-size: 1rem;
    }
    
    .logo-icon {
        width: 32px;
        height: 32px;
    }
    
    .mobile-nav-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 60px;
        left: 0;
        width: 100%;
        height: calc(100vh - 60px);
        background: var(--bg-main);
        padding: 2.5rem 1.5rem;
        border-top: 1px solid var(--border-color);
        transform: translateX(-100%);
        transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
        overflow-y: auto;
        z-index: 999;
        display: block;
    }
    
    .nav-menu.open {
        transform: translateX(0);
    }
    
    .nav-menu ul {
        flex-direction: column;
        gap: 1.5rem;
        align-items: center;
    }
    
    .nav-link {
        font-size: 0.95rem;
        text-align: center;
    }
    
    .vitap-logo-link {
        display: none;
    }
    
    /* Hero Section */
    .hero-section {
        padding-top: 100px;
        padding-bottom: 50px;
        min-height: auto;
    }
    
    .hero-content h1 {
        font-size: 1.8rem;
        line-height: 1.2;
    }
    
    .hero-tagline {
        font-size: 1rem;
        margin-bottom: 1rem;
    }
    
    .hero-description {
        font-size: 0.9rem;
        margin-bottom: 1.5rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        gap: 1rem;
    }
    
    .btn {
        width: 100%;
        padding: 1rem;
        font-size: 0.9rem;
    }
    
    /* Section Headers */
    .section-header h2 {
        font-size: 2rem;
    }
    
    .section-header .section-subtitle {
        font-size: 1rem;
    }
    
    /* Cards & Grids */
    .about-grid, .panel-layout, .cli-container, .project-info-block {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .about-card, .why-card, .feature-box {
        padding: 1.5rem;
    }
    
    .about-card h3, .why-card h3 {
        font-size: 1.1rem;
    }
    
    .comparison-grid, .features-grid, .users-grid, .authors-grid, .compat-grid {
        grid-template-columns: 1fr;
    }
    
    .showcase-container {
        margin: 2rem 0;
    }
    
    .showcase-image {
        max-height: 300px;
    }
    
    .showcase-caption p {
        font-size: 0.9rem;
    }
    
    .download-grid {
        grid-template-columns: 1fr;
    }
    
    .documentation-card {
        flex-direction: column;
        align-items: stretch;
    }
    
    .doc-links {
        flex-direction: column;
    }
    
    /* Photo Placeholders */
    #placeholder-boot {
        min-height: 300px;
    }
    
    /* Table Responsive */
    .comparison-table th, .comparison-table td {
        padding: 1rem 0.75rem;
        font-size: 0.85rem;
    }
    
    .comparison-table th {
        font-size: 0.8rem;
    }
    
    /* Sections Padding */
    .about-section, .why-section, .features-section, 
    .frameworks-section, .command-center-section {
        padding: 60px 0;
    }
    
    .section-header {
        margin-bottom: 2rem;
    }
    
    .section-header h2 {
        font-size: 1.6rem;
    }
    
    /* Badge */
    .badge {
        font-size: 0.65rem;
        padding: 3px 10px;
    }
    
    /* Tag Container */
    .tags-container {
        gap: 6px;
    }
    
    .tag {
        font-size: 0.7rem;
        padding: 4px 10px;
    }
    
    .btn {
        padding: 0.7rem 1.4rem;
        font-size: 0.9rem;
    }
}

/* Small Mobile: 320px - 480px */
@media (max-width: 480px) {
    html {
        font-size: 14px;
    }
    
    .container {
        padding: 0 0.75rem;
    }
    
    /* Header & Navigation */
    .header-container {
        height: 55px;
    }
    
    .logo {
        gap: 6px;
        font-size: 1rem;
    }
    
    .logo-icon {
        width: 28px;
        height: 28px;
    }
    
    .nav-menu {
        top: 55px;
        height: calc(100vh - 55px);
        padding: 2rem 1rem;
    }
    
    .nav-link {
        font-size: 0.95rem;
    }
    
    /* Hero Section */
    .hero-section {
        padding-top: 100px;
        padding-bottom: 40px;
    }
    
    .hero-content h1 {
        font-size: 1.75rem;
        line-height: 1.2;
        margin-bottom: 0.75rem;
    }
    
    .hero-tagline {
        font-size: 1rem;
        margin-bottom: 0.75rem;
    }
    
    .hero-description {
        font-size: 0.95rem;
        margin-bottom: 1.5rem;
        text-align: left;
    }
    
    .badge {
        font-size: 0.65rem;
        padding: 3px 8px;
    }
    
    .btn {
        width: 100%;
        padding: 0.9rem;
        font-size: 0.85rem;
        border-radius: 6px;
    }
    
    /* Section Headers */
    .section-header h2 {
        font-size: 1.5rem;
        margin-bottom: 0.75rem;
    }
    
    .section-header .divider {
        width: 40px;
        height: 3px;
        margin-bottom: 1rem;
    }
    
    .section-header .section-subtitle {
        font-size: 0.9rem;
    }
    
    .subsection-title {
        font-size: 1.3rem;
        margin-bottom: 1.5rem;
    }
    
    /* Cards */
    .about-card, .why-card, .feature-box {
        padding: 1.25rem;
        border-radius: 8px;
    }
    
    .about-card h3, .why-card h3 {
        font-size: 1rem;
        margin-bottom: 0.75rem;
    }
    
    .about-card p, .why-card p {
        font-size: 0.9rem;
        line-height: 1.5;
    }
    
    .highlight-text {
        font-size: 1rem;
        line-height: 1.5;
    }
    
    .tags-container {
        gap: 5px;
        margin-top: 0.75rem;
    }
    
    .tag {
        font-size: 0.7rem;
        padding: 3px 8px;
    }
    
    .card-icon {
        width: 40px;
        height: 40px;
        margin-bottom: 1rem;
    }
    
    .card-icon svg {
        width: 20px;
        height: 20px;
    }
    
    /* Photo Placeholders */
    #placeholder-boot {
        min-height: 220px;
    }
    
    .photo-placeholder-wrapper::before {
        top: -10px;
        left: 12px;
        font-size: 0.65rem;
    }
    
    /* Sections Padding */
    .about-section, .why-section, .features-section, 
    .frameworks-section, .command-center-section {
        padding: 40px 0;
    }
    
    .section-header {
        margin-bottom: 2rem;
    }
    
    /* Specs List */
    .specs-card h3 {
        font-size: 1.05rem;
        margin-bottom: 1.25rem;
    }
    
    .specs-list li {
        font-size: 0.85rem;
        flex-direction: column;
        gap: 0.25rem;
    }
    
    .spec-label {
        font-size: 0.8rem;
    }
    
    .spec-value {
        font-size: 0.85rem;
    }
    
    /* Table Responsive */
    .comparison-table th, .comparison-table td {
        padding: 0.75rem 0.5rem;
        font-size: 0.8rem;
    }
    
    .comparison-table th {
        font-size: 0.75rem;
    }
    
    /* Advantages Container */
    .advantages-container {
        padding: 2rem 1.5rem;
    }
    
    /* Framework Tabs */
    .framework-tabs {
        gap: 8px;
        padding-bottom: 1rem;
    }
    
    .tab-btn {
        padding: 6px 12px;
        font-size: 0.8rem;
    }
    
    /* Panel Layout */
    .panel-layout {
        gap: 2rem;
    }
    
    .panel-info {
        max-width: 100%;
    }
    
    .framework-logo {
        font-size: 0.7rem;
        padding: 3px 10px;
    }
    
    /* CLI Container */
    .cli-container {
        gap: 2rem;
    }
    
    /* Text Alignment */
    body {
        text-align: left;
    }
}

/* Extra Small Mobile: below 320px */
@media (max-width: 319px) {
    html {
        font-size: 13px;
    }
    
    .container {
        padding: 0 0.5rem;
    }
    
    .hero-content h1 {
        font-size: 1.5rem;
    }
    
    .section-header h2 {
        font-size: 1.3rem;
    }
}

/* Landscape Orientation - Mobile Devices */
@media (max-height: 600px) and (max-width: 1024px) {
    .hero-section {
        padding-top: 80px;
        padding-bottom: 40px;
        min-height: auto;
    }
    
    .hero-content h1 {
        font-size: 1.75rem;
        margin-bottom: 0.5rem;
    }
    
    .hero-tagline {
        font-size: 1rem;
        margin-bottom: 0.75rem;
    }
    
    .hero-buttons {
        gap: 0.75rem;
    }
    
    .btn {
        padding: 0.7rem 1.5rem;
        font-size: 0.85rem;
    }
    
    #placeholder-desktop {
        min-height: 250px;
    }
    
    .about-section, .why-section, .features-section, 
    .frameworks-section, .command-center-section {
        padding: 40px 0;
    }
    
    .section-header h2 {
        font-size: 1.75rem;
    }
    
    .section-header {
        margin-bottom: 2rem;
    }
}

/* Accessibility & Print */
@media print {
    .main-header, .mobile-nav-toggle, .btn {
        display: none;
    }
    
    body {
        background: white;
        color: black;
    }
}

/* Focus Visibility for Accessibility */
a:focus, button:focus, input:focus, select:focus, textarea:focus {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* ────────────────────────────────────────────────────────────────────────────
   Contact Section Styles
   ──────────────────────────────────────────────────────────────────────────── */

.contact-section {
    padding: 100px 0;
    background: linear-gradient(135deg, rgba(168, 85, 247, 0.05) 0%, rgba(0, 240, 255, 0.03) 100%);
    border-top: 1px solid var(--border-color);
}

.contact-container {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 60px;
    margin-top: 3rem;
    align-items: start;
}

.contact-info h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-white);
}

.contact-info > p {
    color: var(--text-muted);
    margin-bottom: 2rem;
    line-height: 1.8;
    text-align: left;
}

.contact-details {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.contact-item {
    display: flex;
    gap: 1.5rem;
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background: rgba(13, 20, 38, 0.4);
    transition: all var(--transition-medium);
}

.contact-item:hover {
    border-color: var(--border-glow-hover);
    background: rgba(13, 20, 38, 0.6);
    transform: translateX(5px);
}

.contact-icon {
    width: 32px;
    height: 32px;
    min-width: 32px;
    color: var(--primary);
    stroke-width: 2;
}

.contact-item h4 {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 0.35rem;
    color: var(--text-white);
}

.contact-item p {
    font-size: 0.9rem;
    color: var(--text-muted);
    text-align: left;
}

/* Contact Form Styles */
.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.contact-form label {
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--text-white);
}

.contact-form input,
.contact-form textarea {
    padding: 0.875rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background: rgba(13, 20, 38, 0.5);
    color: var(--text-main);
    font-family: inherit;
    font-size: 0.95rem;
    transition: all var(--transition-fast);
}

.contact-form input:focus,
.contact-form textarea:focus {
    background: rgba(13, 20, 38, 0.8);
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(var(--primary-rgb), 0.1);
    outline: none;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
    color: rgba(148, 163, 184, 0.5);
}

.error-message {
    font-size: 0.8rem;
    color: #ef4444;
    display: none;
    margin-top: -0.5rem;
}

.error-message.show {
    display: block;
}

.form-group.error input,
.form-group.error textarea {
    border-color: #ef4444;
    background: rgba(239, 68, 68, 0.05);
}

.btn-submit {
    margin-top: 0.5rem;
    padding: 1rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-medium);
}

.btn-submit:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 24px rgba(0, 240, 255, 0.2);
}

.btn-submit:active {
    transform: translateY(0);
}

.btn-submit:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.form-status {
    font-size: 0.9rem;
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
    display: none;
}

.form-status.show {
    display: block;
}

.form-status.success {
    color: #10b981;
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.form-status.error {
    color: #ef4444;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
}

/* Responsive: Tablet */
@media (max-width: 768px) {
    .contact-section {
        padding: 60px 0;
    }
    
    .contact-container {
        grid-template-columns: 1fr;
        gap: 40px;
    }
}

/* Responsive: Mobile */
@media (max-width: 640px) {
    .contact-section {
        padding: 40px 0;
    }
    
    .contact-info h3,
    .section-header h2 {
        font-size: 1.3rem;
    }
    
    .contact-details {
        gap: 1rem;
    }
    
    .contact-item {
        padding: 1rem;
        gap: 1rem;
    }
    
    .contact-form {
        gap: 1rem;
    }
    
    .form-group {
        gap: 0.5rem;
    }
    
    .contact-form input,
    .contact-form textarea {
        padding: 0.75rem 0.875rem;
        font-size: 0.9rem;
    }
    
    .btn-submit {
        padding: 0.875rem 1.5rem;
        font-size: 0.95rem;
    }
}
}

/* Reduce Motion for Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ============================================================
   FINAL MOBILE RESPONSIVE OVERRIDES - TESTED & VERIFIED
   ============================================================ */

/* CRITICAL: Mobile Hamburger Menu - Must Show on Mobile */
@media screen and (max-width: 768px) {
    .mobile-nav-toggle {
        display: flex !important;
    }
    
    .nav-menu {
        position: fixed !important;
        left: 0 !important;
        top: 60px !important;
        width: 100% !important;
        height: calc(100vh - 60px) !important;
        background: var(--bg-main) !important;
        padding: 2rem !important;
        border-top: 1px solid var(--border-color) !important;
        transform: translateX(-100%) !important;
        transition: transform 0.3s ease !important;
        z-index: 999 !important;
        overflow-y: auto !important;
        display: block !important;
    }
    
    .nav-menu.open {
        transform: translateX(0) !important;
    }
    
    .nav-menu ul {
        flex-direction: column !important;
        gap: 1.5rem !important;
        align-items: center !important;
    }
    
    .nav-link {
        font-size: 1rem !important;
        text-align: center !important;
    }
}

/* Mobile: 320px - 480px */
@media screen and (max-width: 480px) {
    html {
        font-size: 14px;
    }
    
    .container {
        padding: 0 0.75rem;
    }
    
    .header-container {
        height: 50px;
    }
    
    .logo {
        font-size: 1rem;
        gap: 6px;
    }
    
    .logo-icon {
        width: 28px;
        height: 28px;
    }
    
    .vitap-logo-link {
        display: none;
    }
    
    .hero-section {
        padding-top: 80px;
        padding-bottom: 40px;
    }
    
    .hero-container {
        grid-template-columns: 1fr !important;
    }
    
    .hero-content h1 {
        font-size: 1.5rem;
        line-height: 1.1;
        margin-bottom: 0.5rem;
    }
    
    .hero-tagline {
        font-size: 0.95rem;
        margin-bottom: 0.75rem;
    }
    
    .hero-description {
        font-size: 0.9rem;
        margin-bottom: 1.5rem;
        text-align: left;
    }
    
    .hero-buttons {
        flex-direction: column;
        gap: 0.75rem;
    }
    
    .btn {
        width: 100%;
        padding: 0.8rem 1rem;
    }
    
    .section-header h2 {
        font-size: 1.3rem;
    }
    
    .section-header .divider {
        width: 30px;
    }
    
    .about-grid,
    .comparison-grid,
    .features-grid,
    .why-section .comparison-grid {
        grid-template-columns: 1fr !important;
    }
    
    .about-card,
    .why-card,
    .feature-box {
        padding: 1rem;
    }
    
    #placeholder-desktop,
    #placeholder-boot {
        min-height: 180px;
    }
    
    .tag {
        font-size: 0.65rem;
    }
}

/* Tablet: 481px - 768px */
@media screen and (min-width: 481px) and (max-width: 768px) {
    html {
        font-size: 15px;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .header-container {
        height: 60px;
    }
    
    .logo {
        font-size: 1.1rem;
        gap: 8px;
    }
    
    .logo-icon {
        width: 32px;
        height: 32px;
    }
    
    .vitap-logo-link {
        display: none;
    }
    
    .hero-section {
        padding-top: 100px;
        padding-bottom: 50px;
    }
    
    .hero-container {
        grid-template-columns: 1fr !important;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        gap: 1rem;
    }
    
    .btn {
        width: 100%;
    }
    
    .section-header h2 {
        font-size: 1.75rem;
    }
    
    .comparison-grid,
    .features-grid {
        grid-template-columns: 1fr !important;
    }
}

/* Desktop: 769px+ */
@media screen and (min-width: 769px) {
    .mobile-nav-toggle {
        display: none !important;
    }
    
    .nav-menu {
        display: flex !important;
        position: static !important;
        width: auto !important;
        height: auto !important;
        background: none !important;
        padding: 0 !important;
        border: none !important;
        transform: none !important;
        flex: 1;
        justify-content: center;
    }
    
    .nav-menu ul {
        flex-direction: row !important;
        align-items: center !important;
        gap: 1.8rem !important;
    }
    
    .nav-link {
        font-size: 0.9rem !important;
        text-align: left !important;
    }
}

/* ============================================================
   IMPROVED MOBILE IMAGE RESPONSIVENESS
   ============================================================ */

/* Mobile: Photo Placeholders - Optimized for Small Screens */
@media screen and (max-width: 640px) {
    .photo-placeholder {
        aspect-ratio: 16 / 9;
        min-height: 220px;
        background: #0b0f19;
    }
    
    .photo-placeholder .user-photo {
        object-fit: contain;
        object-position: center;
    }
    
    .placeholder-fallback {
        padding: 2rem 1rem;
    }
    
    .placeholder-icon {
        width: 40px;
        height: 40px;
    }
    
    .placeholder-title {
        font-size: 1rem;
    }
    
    .placeholder-subtitle {
        font-size: 0.8rem;
        max-width: 280px;
    }
}

/* Extra Small Mobile: 320px - 480px */
@media screen and (max-width: 480px) {
    .photo-placeholder {
        aspect-ratio: 16 / 9;
        min-height: 200px;
        background: #0b0f19;
    }
    
    .photo-placeholder .user-photo {
        object-fit: contain;
        object-position: center;
    }
    
    .placeholder-fallback {
        padding: 1.5rem 0.75rem;
    }
    
    .placeholder-icon {
        width: 36px;
        height: 36px;
        margin-bottom: 0.75rem;
    }
    
    .placeholder-title {
        font-size: 0.95rem;
        margin-bottom: 0.4rem;
    }
    
    .placeholder-subtitle {
        font-size: 0.75rem;
        max-width: 240px;
        line-height: 1.4;
    }
    
    /* Terminal Interface Mobile Improvements */
    #placeholder-terminal {
        min-height: 250px;
        aspect-ratio: 3 / 2;
    }
    
    .cli-terminal {
        height: 320px;
    }
    
    .terminal-body {
        font-size: 0.75rem;
        padding: 1rem;
    }
    
    .terminal-line {
        margin-bottom: 4px;
    }
    
    .terminal-header {
        padding: 8px 12px;
    }
    
    .window-title {
        font-size: 0.65rem;
    }
}