/* Modern Engineering Theme - Inspired by Vercel/Linear */
:root {
    --bg-primary: #000000;
    --bg-secondary: #0a0a0a;
    --border-color: #222222;
    --border-hover: #444444;
    
    --text-primary: #ededed;
    --text-secondary: #888888;
    --text-muted: #666666;
    
    --accent: #ffffff;
    --accent-bg: #111111;
    
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;
    
    --transition: all 0.25s ease;
}

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

html {
    scroll-behavior: smooth;
    background-color: var(--bg-primary);
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

/* Typography */
h1, h2, h3, h4 {
    font-weight: 600;
    line-height: 1.2;
    letter-spacing: -0.03em;
    color: var(--text-primary);
}

.section-header {
    margin-bottom: 3rem;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.section-desc {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.text-center { text-align: center; }
.mt-4 { margin-top: 2rem; }

/* Layout Components */
.section {
    padding: 6rem 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.section-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 2rem;
    width: 100%;
}

/* Cards (Bento Box Style) */
.card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    transition: var(--transition);
}

.card:hover {
    border-color: var(--border-hover);
    background-color: var(--accent-bg);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    font-weight: 500;
    font-size: 0.95rem;
    cursor: pointer;
    transition: var(--transition);
    gap: 0.5rem;
}

.btn-primary {
    background-color: var(--accent);
    color: var(--bg-primary);
    border: 1px solid var(--accent);
}

.btn-primary:hover {
    background-color: transparent;
    color: var(--accent);
}

.btn-secondary {
    background-color: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

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

/* Tags (Tech Stack) */
.tag {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background-color: #1a1a1a;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: #a1a1a6;
    margin: 0.25rem 0.5rem 0.25rem 0;
    transition: var(--transition);
}

.card:hover .tag {
    border-color: #333;
    color: #ccc;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0; left: 0; width: 100%;
    z-index: 1000;
    background: transparent;
    transition: var(--transition);
    border-bottom: 1px solid transparent;
}

.navbar.scrolled {
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
}

.nav-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 1.25rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.05em;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

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

.menu-toggle {
    display: none;
    font-size: 1.25rem;
    cursor: pointer;
}

/* Hero Section */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 0;
}

.hero-content {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 2rem;
    text-align: left; /* Aligned left for a more technical feel */
    width: 100%;
}

.hero-title {
    font-size: 5.5rem;
    font-weight: 700;
    letter-spacing: -0.05em;
    margin-bottom: 1.5rem;
}

.line-wrap {
    overflow: hidden;
    padding-bottom: 5px;
}

.hero-title .anim-text {
    display: inline-block;
    color: var(--text-primary);
    animation: revealUp 1s cubic-bezier(0.16, 1, 0.3, 1) forwards;
    transform: translateY(120%);
    opacity: 0;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 400;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 3rem;
    max-width: 700px;
}

.hero-subtitle .anim-text {
    display: inline-block;
    animation: revealUp 1s cubic-bezier(0.16, 1, 0.3, 1) forwards;
    transform: translateY(120%);
    opacity: 0;
}

.delay-1 { animation-delay: 0.15s !important; }
.delay-2 { animation-delay: 0.3s !important; }
.delay-3 { animation-delay: 0.5s !important; }

@keyframes revealUp {
    0% { transform: translateY(120%); opacity: 0; }
    100% { transform: translateY(0); opacity: 1; }
}

.anim-fade {
    opacity: 0;
    animation: fadeIn 1.2s ease forwards;
}

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

.hero-cta {
    display: flex;
    gap: 1rem;
}

/* Featured Project */
.featured-project {
    margin-bottom: 3rem;
    padding: 3rem;
    border: 1px solid var(--border-color);
    background: linear-gradient(145deg, #0a0a0a 0%, #050505 100%);
    position: relative;
    overflow: hidden;
}

.featured-project:hover {
    border-color: rgba(255, 255, 255, 0.15);
}

.featured-project::after {
    content: '';
    position: absolute;
    top: -50%;
    right: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(255,255,255,0.02) 0%, transparent 60%);
    pointer-events: none;
}

.featured-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1.5rem;
    position: relative;
    z-index: 2;
}

.featured-title {
    font-size: 2.2rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    background: linear-gradient(135deg, #ffffff 0%, #888888 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.5rem;
}

.featured-description {
    font-size: 1.1rem;
    color: var(--text-primary);
    line-height: 1.6;
    margin-bottom: 2.5rem;
    max-width: 900px;
    position: relative;
    z-index: 2;
}

.feature-highlights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-bottom: 1.5rem;
    position: relative;
    z-index: 2;
}

.feature-item h4 {
    font-size: 1.05rem;
    color: #fff;
    margin-bottom: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.feature-item h4 i {
    color: var(--text-secondary);
}

.feature-item p {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.other-projects-title {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
    font-weight: 600;
}

/* Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 1.5rem;
}

.project-card {
    display: flex;
    flex-direction: column;
}

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.75rem;
}

.project-header h3 {
    font-size: 1.25rem;
}

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

.project-links a {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.project-links a:hover {
    color: var(--text-primary);
}

.project-subtitle {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 1.25rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.project-description {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

/* Skills Grid */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.skill-category h3 {
    margin-bottom: 1.25rem;
    font-size: 1.1rem;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.25rem;
}

/* Achievements Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}

.stat-card {
    text-align: left;
}

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

.stat-label {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.profile-links {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-top: 1.5rem;
}

.profile-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.2rem;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 0.9rem;
}

.profile-btn:hover {
    background: var(--accent-bg);
    border-color: var(--border-hover);
}

/* Background (Timeline) Section */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.about-grid h3 {
    font-size: 1.2rem;
    margin-bottom: 1.5rem;
}

.timeline {
    position: relative;
    padding-left: 1.25rem;
    border-left: 1px solid var(--border-color);
}

.timeline-item {
    position: relative;
    margin-bottom: 2rem;
}

.timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-item::before {
    content: '';
    position: absolute;
    left: -1.5rem; /* Adjust based on padding + border */
    top: 0.4rem;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--text-muted);
    border: 2px solid var(--bg-secondary);
}

.timeline-item h4 {
    font-size: 1rem;
    margin-bottom: 0.25rem;
}

.timeline-item .institution {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 0.25rem;
}

.timeline-item .duration {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* Contact Section */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    max-width: 900px;
    margin: 0 auto;
}

.contact-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 2.5rem;
}

.contact-card i {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.icon-svg {
    width: 32px;
    height: 32px;
    margin-bottom: 1rem;
    fill: var(--text-primary);
}

.contact-card h3 {
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.contact-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Footer */
footer {
    padding: 2rem;
    text-align: center;
    border-top: 1px solid var(--border-color);
}

footer p {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* Animations (Scroll Reveal) */
.reveal {
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.8s ease;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive */
@media (max-width: 992px) {
    .hero-title { font-size: 4.5rem; }
    .about-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .nav-links {
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: var(--bg-primary);
        border-bottom: 1px solid var(--border-color);
        flex-direction: column;
        padding: 2rem;
        gap: 1.5rem;
        clip-path: polygon(0 0, 100% 0, 100% 0, 0 0);
        transition: clip-path 0.3s ease;
    }
    .nav-links.active {
        clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%);
    }
    .menu-toggle { display: block; }
    
    .hero-title { font-size: 3.2rem; }
    .hero-subtitle { font-size: 1.1rem; }
    
    .section-title { font-size: 2rem; }
    .section { padding: 4rem 0; }
    
    .hero-cta { flex-direction: column; width: 100%; max-width: 250px; }
}