:root {
    --bg: #050505;
    --surface: #111111;
    --surface-hover: #1a1a1a;
    --accent: #007aff;
    --accent-glow: rgba(0, 122, 255, 0.4);
    --text: #e0e0e0;
    --text-dim: #909090;
    --border: #2a2a2a;
}

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

body {
    background-color: var(--bg);
    background-image: 
        radial-gradient(circle at 15% 50%, rgba(0, 122, 255, 0.08), transparent 25%),
        radial-gradient(circle at 85% 30%, rgba(0, 122, 255, 0.05), transparent 25%);
    background-attachment: fixed;
    color: var(--text);
    font-family: 'Inter', -apple-system, sans-serif;
    line-height: 1.6;
}

/* Nav */
nav {
    position: fixed;
    top: 0; width: 100%;
    padding: 1.5rem;
    background: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(10px);
    z-index: 100;
    border-bottom: 1px solid var(--border);
}

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

.nav-links a {
    color: var(--text-dim);
    text-decoration: none;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: color 0.3s;
}

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

/* Hero */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 2rem;
}

.hero h1 { font-size: 4rem; font-weight: 700; margin-bottom: 0.5rem; }
.tagline { font-size: 1.5rem; color: var(--accent); font-weight: 500; }

.hero-description {
    color: var(--text-dim);
    font-size: 1.15rem;
    max-width: 650px;
    margin: 1.5rem auto 2.5rem auto;
    line-height: 1.7;
}

.hero-description strong {
    color: var(--text);
    font-weight: 600;
}

.hero-links { display: flex; gap: 1.5rem; justify-content: center; }
.hero-links a { 
    color: var(--text); text-decoration: none; 
    padding: 0.5rem 1rem; border: 1px solid var(--border); 
    border-radius: 4px; transition: 0.3s;
}
.hero-links a:hover { border-color: var(--accent); background: #007aff10; }

/* Sections */
.section { padding: 8rem 10%; max-width: 1400px; margin: 0 auto; }
.section-title { font-size: 2rem; margin-bottom: 4rem; text-align: center; color: var(--accent); }

/* Projects */
.project-list { display: flex; flex-direction: column; gap: 8rem; }
.project-item { display: grid; grid-template-columns: 1.2fr 1fr; gap: 4rem; align-items: center; }
.project-item.reverse-layout { grid-template-columns: 1fr 1.2fr; }
.project-item.reverse-layout .project-visual { grid-column: 2; grid-row: 1; }
.project-item.reverse-layout .project-info { grid-column: 1; grid-row: 1; }

.project-visual { 
    background: var(--surface); 
    aspect-ratio: 16/9; 
    border-radius: 8px; 
    border: 1px solid var(--border);
    display: flex; align-items: center; justify-content: center;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

.video-placeholder { color: var(--text-dim); font-style: italic; }
.project-video { width: 100%; height: 100%; object-fit: cover; }

.project-info h3 { font-size: 2rem; margin-bottom: 0.5rem; line-height: 1.2; }
.project-meta { color: var(--accent); font-family: monospace; font-size: 0.95rem; margin-bottom: 1rem; }
.description { margin-bottom: 1.5rem; color: var(--text-dim); font-size: 1.05rem; }

.highlights { 
    padding-left: 1.2rem; 
    font-size: 0.95rem; 
    margin-bottom: 2rem;
    color: var(--text-dim);
}
.highlights li { margin-bottom: 0.5rem; }

.project-links { display: flex; gap: 1.5rem; }
.github-link { color: var(--text); text-decoration: none; font-weight: 600; border-bottom: 2px solid var(--accent); padding-bottom: 2px; }
.youtube-link { color: var(--text); text-decoration: none; font-weight: 600; border-bottom: 2px solid #ff0000; padding-bottom: 2px; }
.youtube-link:hover { color: #ff0000; }

/* Subtitles */
.section-subtitle {
    margin-top: 8rem;
    margin-bottom: 3rem;
    font-size: 1.8rem;
    color: var(--text);
    text-align: center;
}

/* Engine & Simulation Grid */
.engine-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
}

/* Small Experiments Grid */
.experiments-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.experiment-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    display: flex;
    overflow: hidden;
    height: 120px;
    align-items: center;
    transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s;
    position: relative;
}

.experiment-card:hover {  
    transform: translateY(-3px); 
    border-color: var(--accent); 
    box-shadow: 0 5px 15px rgba(0,0,0,0.4);
}

.exp-video {
    width: 130px;
    height: 100%;
    object-fit: cover;
    background: #1a1a1a;
    flex-shrink: 0;
    border-right: 1px solid var(--border);
}

.exp-info {
    padding: 1rem 1.2rem;
    display: flex;
    flex-direction: column;
    justify-content: center;
    flex-grow: 1;
    position: relative;
    height: 100%;
}

.exp-info h4 { 
    font-size: 1.05rem; 
    margin-bottom: 0.2rem; 
}

.exp-info .project-meta { 
    margin-bottom: 0; 
    font-size: 0.8rem; 
}

.exp-links {
    position: absolute;
    bottom: 1rem;
    right: 1.2rem;
    display: flex;
    gap: 0.8rem;
}

.exp-links a { 
    font-size: 1.2rem; 
    border: none; 
    color: var(--text);
    opacity: 0.8;
    transition: opacity 0.2s, color 0.2s;
}

.exp-links a:hover { opacity: 1; padding-bottom: 0; }
.exp-links .github-link:hover { color: var(--accent); }
.exp-links .youtube-link:hover { color: #ff0000; }

.project-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    transition: transform 0.2s, border-color 0.2s;
}

.project-card:hover {
    transform: translateY(-5px);
    border-color: var(--accent);
}

.card-video {
    width: 100%;
    aspect-ratio: 16/9;
    border-radius: 4px;
    object-fit: cover;
    margin-bottom: 1rem;
    background: #1a1a1a; /* Placeholder bg */
}

.project-card h4 {
    font-size: 1.25rem;
    margin-bottom: 0.25rem;
}

.project-card .project-meta {
    font-size: 0.85rem;
    margin-bottom: 0.8rem;
}

.project-card .description {
    font-size: 0.95rem;
    flex-grow: 1; /* Pushes the links to the bottom */
}

/* GitHub Call to Action */
.github-cta {
    margin-top: 4rem;
    padding: 4rem 2rem;
    background: var(--surface);
    border: 1px dashed var(--border);
    border-radius: 12px;
    text-align: center;
    position: relative;
    overflow: hidden;
    transition: border-color 0.3s ease;
}
.github-cta:hover {
    border-color: var(--accent);
}
.github-cta::before {
    content: ''; position: absolute;
    top: -50%; left: -50%; width: 200%; height: 200%;
    background: radial-gradient(circle at 50% 50%, var(--accent-glow), transparent 60%);
    opacity: 0.1;
    pointer-events: none;
}
.github-cta h3 {
    font-size: 1.8rem;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.8rem;
}
.github-cta p {
    color: var(--text-dim);
    margin-bottom: 2rem;
    font-size: 1.1rem;
}
.github-btn {
    background: #24292e; /* Original GitHub dark color mixed with the tech theme */
}
.github-btn:hover {
    background: #2f363d;
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.15);
}

/* Buttons */
.btn-primary { 
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem; 
    background: var(--accent); 
    color: white; 
    text-decoration: none; 
    border-radius: 6px; 
    font-weight: 600;
    transition: all 0.3s ease;
}

.glow-btn:hover {
    box-shadow: 0 0 15px var(--accent-glow);
    transform: translateY(-2px);
}

/* Resume Section */
.resume-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 3rem;
    display: flex;
    align-items: center;
    gap: 2rem;
    max-width: 800px;
    margin: 0 auto;
    position: relative;
    overflow: hidden;
}
.resume-card::before {
    content: ''; position: absolute; top: 0; left: 0; width: 4px; height: 100%;
    background: var(--accent);
}
.resume-icon {
    font-size: 4rem;
    color: var(--accent);
    opacity: 0.8;
}
.resume-content h3 { font-size: 1.5rem; margin-bottom: 0.5rem; }
.resume-content p { color: var(--text-dim); margin-bottom: 1.5rem; }

/* Contact Section */
.contact-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 3rem;
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}
.contact-desc {
    font-size: 1.1rem;
    color: var(--text-dim);
    margin-bottom: 2.5rem;
}
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}
.contact-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.8rem;
    padding: 1.5rem;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
    text-decoration: none;
    transition: all 0.3s ease;
}
.contact-btn i { font-size: 2rem; color: var(--accent); transition: transform 0.3s; }
.contact-btn span { font-weight: 500; font-size: 0.95rem; }

.contact-btn:hover {
    border-color: var(--accent);
    background: var(--surface-hover);
    transform: translateY(-3px);
}
.contact-btn:hover i { transform: scale(1.1); }

/* Footer */
footer { text-align: center; padding: 4rem; border-top: 1px solid var(--border); color: var(--text-dim); }

@media (max-width: 900px) {
    .project-item { grid-template-columns: 1fr !important; }
    .project-item.reverse-layout .project-visual { grid-column: 1; grid-row: 1; }
    .project-item.reverse-layout .project-info { grid-column: 1; grid-row: 2; }
    .hero h1 { font-size: 2.5rem; }
    .resume-card { flex-direction: column; text-align: center; }
}