/* ===================================
   AD ENGINEERING - CSS STYLESHEET
   Distinctive aerospace design
   =================================== */

/* CSS Variables */
:root {
    /* Colors */
    --navy-primary: #1a2332;
    --navy-dark: #0f1419;
    --navy-light: #2a3544;
    --crimson: #c41e3a;
    --crimson-dark: #9a1629;
    --steel-gray: #64748b;
    --steel-light: #94a3b8;
    --steel-dark: #475569;
    --white: #ffffff;
    --off-white: #f8fafc;
    --accent-blue: #3b82f6;
    
    /* Typography */
    --font-primary: 'Rajdhani', sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    /* Spacing */
    --section-padding: 120px;
    --container-max: 1400px;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-smooth: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    color: var(--navy-primary);
    background: var(--off-white);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 40px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Navigation */
.main-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(26, 35, 50, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
}

.logo {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.logo-text {
    font-size: 64px;
    font-weight: 700;
    color: var(--white);
    letter-spacing: 2px;
}

.logo-subtitle {
    font-size: 12px;
    color: var(--crimson);
    font-weight: 600;
    letter-spacing: 4px;
}

.nav-links {
    display: flex;
    gap: 40px;
    list-style: none;
}

.nav-links a {
    color: var(--white);
    font-size: 16px;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: var(--transition-fast);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--crimson);
    transition: var(--transition-smooth);
}

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

.cta-nav {
    padding: 8px 20px;
    background: var(--crimson);
    border-radius: 4px;
}

.cta-nav::after {
    display: none;
}

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

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

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    padding-top: 80px;
    background: linear-gradient(135deg, var(--navy-dark) 0%, var(--navy-primary) 100%);
    overflow: hidden;
}

.hero-background {
    position: absolute;
    inset: 0;
    opacity: 0.4;
}

.grid-overlay {
    position: absolute;
    inset: 0;
    background-image: 
        linear-gradient(rgba(59, 130, 246, 0.1) 1px, transparent 1px),
        linear-gradient(90deg, rgba(59, 130, 246, 0.1) 1px, transparent 1px);
    background-size: 50px 50px;
    animation: gridMove 20s linear infinite;
}

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

.aerospace-lines {
    position: absolute;
    inset: 0;
    background: 
        linear-gradient(45deg, transparent 48%, var(--crimson) 48%, var(--crimson) 52%, transparent 52%),
        linear-gradient(-45deg, transparent 48%, rgba(59, 130, 246, 0.3) 48%, rgba(59, 130, 246, 0.3) 52%, transparent 52%);
    background-size: 400px 400px;
    opacity: 0.1;
    animation: diagonalMove 30s linear infinite;
}

@keyframes diagonalMove {
    0% { background-position: 0 0; }
    100% { background-position: 400px 400px; }
}

.hero-content {
    position: relative;
    z-index: 2;
    animation: fadeInUp 1s ease-out;
}

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

.badge-group {
    display: flex;
    gap: 15px;
    margin-bottom: 30px;
}

.badge {
    padding: 8px 16px;
    background: rgba(196, 30, 58, 0.2);
    border: 1px solid var(--crimson);
    border-radius: 4px;
    color: var(--white);
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 2px;
    font-family: var(--font-mono);
}

.hero-title {
    font-size: clamp(36px, 5vw, 64px);
    color: var(--white);
    margin-bottom: 30px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.title-line-1 {
    animation: fadeInUp 1s ease-out 0.2s both;
}

.title-line-2 {
    color: var(--steel-light);
    animation: fadeInUp 1s ease-out 0.4s both;
}

.hero-subtitle {
    font-size: 22px;
    color: var(--steel-light);
    max-width: 700px;
    margin-bottom: 50px;
    animation: fadeInUp 1s ease-out 0.6s both;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    max-width: 900px;
    margin-bottom: 50px;
    animation: fadeInUp 1s ease-out 0.8s both;
}

.stat {
    display: flex;
    flex-direction: column;
    gap: 8px;
    padding: 20px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    transition: var(--transition-smooth);
}

.stat:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--crimson);
    transform: translateY(-5px);
}

.stat-number {
    font-size: 36px;
    font-weight: 700;
    color: var(--crimson);
    font-family: var(--font-mono);
}

.stat-label {
    font-size: 14px;
    color: var(--steel-light);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.hero-cta {
    display: flex;
    gap: 20px;
    animation: fadeInUp 1s ease-out 1s both;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 16px 32px;
    font-size: 16px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    border-radius: 4px;
    transition: var(--transition-smooth);
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover {
    background: var(--crimson-dark);
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(196, 30, 58, 0.3);
}

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

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

/* Scroll Indicator */
.scroll-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    color: var(--steel-light);
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 2px;
    animation: bounce 2s infinite;
}

.scroll-line {
    width: 1px;
    height: 40px;
    background: linear-gradient(to bottom, var(--crimson), transparent);
}

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

/* Profile Bar */
.profile-bar {
    background: var(--white);
    border-bottom: 2px solid var(--crimson);
    padding: 30px 0;
}

.profile-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 30px;
}

.profile-item {
    display: flex;
    flex-direction: column;
    gap: 8px;
    text-align: center;
}

.profile-label {
    font-size: 12px;
    color: var(--steel-gray);
    text-transform: uppercase;
    letter-spacing: 2px;
    font-weight: 600;
}

.profile-value {
    font-size: 16px;
    color: var(--navy-primary);
    font-weight: 700;
    font-family: var(--font-mono);
}

/* Section Titles */
.section-title {
    font-size: clamp(36px, 5vw, 56px);
    color: var(--navy-primary);
    margin-bottom: 20px;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 80px;
    height: 4px;
    background: var(--crimson);
}

.section-subtitle {
    font-size: 20px;
    color: var(--steel-gray);
    max-width: 800px;
}

.section-header {
    margin-bottom: 60px;
}

/* Differentiators Section */
.differentiators {
    padding: var(--section-padding) 0;
    background: var(--white);
}

.diff-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
    margin-top: 60px;
}

.diff-card {
    padding: 40px;
    background: var(--off-white);
    border: 2px solid transparent;
    border-radius: 8px;
    transition: var(--transition-smooth);
}

.diff-card:hover {
    border-color: var(--crimson);
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(26, 35, 50, 0.1);
}

.diff-icon {
    width: 64px;
    height: 64px;
    margin-bottom: 20px;
    color: var(--crimson);
}

.diff-card h3 {
    font-size: 24px;
    color: var(--navy-primary);
    margin-bottom: 15px;
}

.diff-card p {
    color: var(--steel-gray);
    font-size: 16px;
    line-height: 1.8;
}

/* Capabilities Section */
.capabilities {
    padding: var(--section-padding) 0;
    background: linear-gradient(135deg, var(--navy-dark) 0%, var(--navy-primary) 100%);
    color: var(--white);
}

.capabilities .section-title {
    color: var(--white);
}

.capabilities .section-subtitle {
    color: var(--steel-light);
}

.capabilities-content {
    display: grid;
    gap: 60px;
    margin-top: 60px;
}

.capability-category {
    background: rgba(255, 255, 255, 0.05);
    padding: 40px;
    border-radius: 8px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.category-title {
    font-size: 28px;
    color: var(--crimson);
    margin-bottom: 30px;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.capability-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.capability-list li {
    display: flex;
    flex-direction: column;
    gap: 8px;
    padding-left: 30px;
    position: relative;
}

.capability-list li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--crimson);
    font-size: 20px;
}

.capability-list strong {
    font-size: 18px;
    color: var(--white);
}

.capability-list span {
    font-size: 16px;
    color: var(--steel-light);
    line-height: 1.6;
}

.tools-section {
    margin-top: 60px;
    padding: 40px;
    background: rgba(196, 30, 58, 0.1);
    border-radius: 8px;
    border: 1px solid var(--crimson);
}

.tools-section h4 {
    font-size: 24px;
    margin-bottom: 20px;
    color: var(--white);
}

.tools-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
}

.tool-badge {
    padding: 10px 20px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    font-size: 14px;
    font-weight: 600;
    font-family: var(--font-mono);
}

/* Projects Section */
.projects {
    padding: var(--section-padding) 0;
    background: var(--off-white);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 60px;
}

.project-card {
    padding: 40px;
    background: var(--white);
    border: 2px solid var(--steel-light);
    border-radius: 8px;
    transition: var(--transition-smooth);
    position: relative;
}

.project-card:hover {
    border-color: var(--crimson);
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(26, 35, 50, 0.15);
}

.project-number {
    position: absolute;
    top: -20px;
    right: 30px;
    font-size: 72px;
    font-weight: 700;
    color: rgba(196, 30, 58, 0.1);
    font-family: var(--font-mono);
}

.project-card h3 {
    font-size: 22px;
    color: var(--navy-primary);
    margin-bottom: 15px;
}

.project-card p {
    color: var(--steel-gray);
    margin-bottom: 20px;
    line-height: 1.7;
}

.project-tag {
    display: inline-block;
    padding: 6px 12px;
    background: var(--crimson);
    color: var(--white);
    font-size: 12px;
    font-weight: 600;
    border-radius: 4px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Publications Section */
.publications {
    padding: var(--section-padding) 0;
    background: var(--white);
}

.publications-featured {
    display: grid;
    gap: 30px;
    margin-top: 60px;
}

.pub-card {
    padding: 30px;
    background: var(--off-white);
    border-left: 4px solid var(--steel-gray);
    border-radius: 4px;
    transition: var(--transition-smooth);
}

.pub-card:hover {
    border-left-color: var(--crimson);
    transform: translateX(10px);
    box-shadow: 0 10px 30px rgba(26, 35, 50, 0.1);
}

.pub-card.featured {
    background: linear-gradient(135deg, var(--navy-dark) 0%, var(--navy-primary) 100%);
    color: var(--white);
    border-left-color: var(--crimson);
    padding: 40px;
}

.pub-type {
    display: inline-block;
    padding: 6px 12px;
    background: var(--crimson);
    color: var(--white);
    font-size: 11px;
    font-weight: 600;
    border-radius: 4px;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 15px;
}

.pub-card h3 {
    font-size: 22px;
    color: var(--navy-primary);
    margin-bottom: 10px;
}

.pub-card.featured h3 {
    color: var(--white);
    font-size: 28px;
}

.pub-authors {
    font-size: 14px;
    color: var(--steel-gray);
    font-style: italic;
    margin-bottom: 5px;
}

.pub-card.featured .pub-authors {
    color: var(--steel-light);
}

.pub-venue {
    font-size: 15px;
    color: var(--steel-gray);
    font-weight: 600;
    margin-bottom: 15px;
}

.pub-card.featured .pub-venue {
    color: var(--crimson);
}

.pub-description {
    font-size: 16px;
    color: var(--steel-gray);
    line-height: 1.7;
    margin-bottom: 15px;
}

.pub-card.featured .pub-description {
    color: var(--steel-light);
}

.pub-link {
    color: var(--crimson);
    font-weight: 600;
    transition: var(--transition-fast);
}

.pub-link:hover {
    color: var(--crimson-dark);
    text-decoration: underline;
}

.pub-card.featured .pub-link {
    color: var(--white);
    border-bottom: 2px solid var(--crimson);
    padding-bottom: 2px;
}

.publications-full {
    margin-top: 40px;
    padding: 30px;
    background: var(--off-white);
    border-radius: 8px;
}

.publications-full summary {
    font-size: 18px;
    font-weight: 600;
    color: var(--navy-primary);
    cursor: pointer;
    list-style: none;
    display: flex;
    align-items: center;
    gap: 10px;
}

.publications-full summary::before {
    content: '▸';
    color: var(--crimson);
    transition: var(--transition-fast);
}

.publications-full[open] summary::before {
    transform: rotate(90deg);
}

.pub-list-full {
    margin-top: 30px;
}

.pub-list-full ol {
    padding-left: 25px;
}

.pub-list-full li {
    margin-bottom: 15px;
    color: var(--steel-gray);
    line-height: 1.7;
}

/* About Section */
.about {
    padding: var(--section-padding) 0;
    background: var(--off-white);
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 80px;
    margin-top: 60px;
}

.about-text p {
    font-size: 18px;
    color: var(--steel-gray);
    margin-bottom: 25px;
    line-height: 1.8;
}

.credentials {
    margin-top: 50px;
}

.credentials h3 {
    font-size: 28px;
    color: var(--navy-primary);
    margin-bottom: 20px;
}

.leader-card {
    background: var(--white);
    padding: 30px;
    border-radius: 8px;
    border: 2px solid var(--crimson);
}

.leader-card h4 {
    font-size: 24px;
    color: var(--navy-primary);
    margin-bottom: 5px;
}

.leader-title {
    font-size: 16px;
    color: var(--crimson);
    font-weight: 600;
    margin-bottom: 20px;
}

.leader-quals {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.leader-quals li {
    padding-left: 25px;
    position: relative;
    color: var(--steel-gray);
    font-size: 16px;
}

.leader-quals li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--crimson);
    font-weight: 700;
}

.certifications {
    margin-top: 50px;
}

.certifications h3 {
    font-size: 28px;
    color: var(--navy-primary);
    margin-bottom: 20px;
}

.certifications ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.certifications li {
    padding-left: 25px;
    position: relative;
    color: var(--steel-gray);
    font-size: 16px;
    line-height: 1.7;
}

.certifications li::before {
    content: '●';
    position: absolute;
    left: 0;
    color: var(--crimson);
}

.about-sidebar {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.info-box {
    background: var(--white);
    padding: 30px;
    border-radius: 8px;
    border: 1px solid var(--steel-light);
}

.info-box h3 {
    font-size: 20px;
    color: var(--navy-primary);
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 2px solid var(--crimson);
}

.info-box ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.info-box li {
    color: var(--steel-gray);
    font-size: 15px;
    padding-left: 20px;
    position: relative;
}

.info-box li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--crimson);
}

/* Contact Section */
.contact {
    padding: var(--section-padding) 0;
    background: linear-gradient(135deg, var(--navy-dark) 0%, var(--navy-primary) 100%);
    color: var(--white);
}

.contact .section-title {
    color: var(--white);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    margin-top: 60px;
}

.contact-info p {
    font-size: 18px;
    color: var(--steel-light);
    margin-bottom: 40px;
    line-height: 1.7;
}

.contact-details {
    display: flex;
    flex-direction: column;
    gap: 25px;
    margin-bottom: 50px;
}

.contact-item {
    display: flex;
    gap: 20px;
    padding: 20px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.contact-item svg {
    flex-shrink: 0;
    color: var(--crimson);
}

.contact-item .label {
    display: block;
    font-size: 12px;
    color: var(--steel-light);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 5px;
}

.contact-item a,
.contact-item span {
    font-size: 18px;
    color: var(--white);
    font-weight: 600;
}

.contact-item a:hover {
    color: var(--crimson);
}

.cta-section {
    padding: 30px;
    background: rgba(196, 30, 58, 0.1);
    border: 2px solid var(--crimson);
    border-radius: 8px;
}

.cta-section h3 {
    font-size: 24px;
    color: var(--white);
    margin-bottom: 10px;
}

.cta-section p {
    font-size: 16px;
    color: var(--steel-light);
    margin-bottom: 20px;
}

.contact-form-wrapper {
    background: rgba(255, 255, 255, 0.05);
    padding: 40px;
    border-radius: 8px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.contact-form h3 {
    font-size: 28px;
    color: var(--white);
    margin-bottom: 30px;
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    font-size: 14px;
    color: var(--steel-light);
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 15px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    color: var(--white);
    font-family: var(--font-primary);
    font-size: 16px;
    transition: var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--crimson);
    background: rgba(255, 255, 255, 0.1);
}

.form-group textarea {
    resize: vertical;
}

/* Footer */
.footer {
    background: var(--navy-dark);
    color: var(--steel-light);
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h4 {
    color: var(--white);
    font-size: 18px;
    margin-bottom: 20px;
}

.footer-col p,
.footer-col li {
    font-size: 14px;
    line-height: 1.8;
}

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

.footer-col li {
    margin-bottom: 10px;
}

.footer-col a {
    transition: var(--transition-fast);
}

.footer-col a:hover {
    color: var(--crimson);
}

.footer-bottom {
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-bottom p {
    font-size: 14px;
}

/* Responsive Design */
@media (max-width: 1024px) {
    :root {
        --section-padding: 80px;
    }
    
    .container {
        padding: 0 30px;
    }
    
    .profile-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .about-content {
        grid-template-columns: 1fr;
        gap: 50px;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 50px;
    }
    
    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .hero-stats {
        grid-template-columns: 1fr;
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .profile-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }
    
    .diff-grid {
        grid-template-columns: 1fr;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: 10px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 20px;
    }
    
    .badge-group {
        flex-direction: column;
    }
    
    .profile-grid {
        grid-template-columns: 1fr;
    }
}