:root {
    /* Light Theme Variables */
    --primary: #000000;
    --accent: #0ea5e9; 
    --bg: #ffffff;
    --text: #111827;
    --text-muted: #6b7280;
    --section-bg: #fafafa;
    --card-bg: #fafafa;
    --card-hover: #ffffff;
    --border: #eee;
    --nav-bg: rgba(255, 255, 255, 0.95);
    --section-padding: 25px 0;
    --max-content-width: 1200px;
}

* {
    box-sizing: border-box;
    -webkit-font-smoothing: antialiased;
    scroll-behavior: smooth;
}

/* Custom Selection Color */
::selection {
    background-color: var(--accent);
    color: white;
}

body {
    margin: 0;
    font-family: 'Inter', sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
    padding-top: 70px; 
}

/* --- GLOBAL CONTAINER --- */
.container {
    max-width: var(--max-content-width);
    margin: 0 auto;
    padding: 0 5%; 
    width: 100%;
}

/* --- NAVIGATION --- */
nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: var(--nav-bg);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--border);
    padding: 20px 0;
}

nav .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    font-weight: 900;
    font-size: 1.2rem;
    letter-spacing: -1px;
    text-decoration: none;
    color: var(--primary);
}

.nav-links {
    display: flex;
    gap: 30px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-muted);
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: color 0.3s;
}

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

/* --- HERO SECTION --- */
.hero {
    min-height: 80vh;
    display: flex;
    align-items: center;
    padding: var(--section-padding);
    background: var(--section-bg);
}

.hero-grid {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    align-items: center;
    width: 100%;
    gap: 60px;
}

.hero-content h1 {
    font-size: clamp(4rem, 10vw, 7rem);
    font-weight: 900;
    line-height: 0.85;
    margin: 0;
    letter-spacing: -4px;
    text-transform: uppercase;
    color: var(--primary);
}

.title-sub {
    font-size: 1.2rem;
    font-weight: 400;
    color: var(--text-muted);
    margin-bottom: 25px;
    letter-spacing: 6px;
    text-transform: uppercase;
}

.avatar-box {
    display: flex;
    justify-content: flex-end;
}

.profile-pic {
    width: 400px; 
    height: 400px; 
    object-fit: cover;
    border-radius: 50%;
    border: 15px solid var(--bg);
    background: linear-gradient(135deg, #0ea5e9 0%, #2563eb 100%);
    box-shadow: 0 30px 60px rgba(0,0,0,0.12);
}

/* --- BUTTONS --- */
.btn-group {
    margin-top: 50px;
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.btn {
    padding: 20px 45px;
    text-decoration: none;
    font-weight: 700;
    font-size: 0.8rem;
    letter-spacing: 2px;
    text-transform: uppercase;
    border-radius: 2px;
    transition: all 0.4s ease;
}

.btn-black { 
    background: var(--primary); 
    color: var(--bg); 
}
.btn-outline { 
    border: 2px solid var(--primary); 
    color: var(--primary); 
}
.btn:hover { 
    transform: translateY(-5px); 
    box-shadow: 0 10px 20px rgba(0,0,0,0.1); 
}

/* --- CONTENT SECTIONS --- */
section { padding: var(--section-padding); }

.section-heading h2 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 900;
    letter-spacing: -3px;
    margin-bottom: 10px;
    color: var(--primary);
}

.intro-text {
    font-size: 2rem;
    font-weight: 300;
    line-height: 1.4;
    max-width: 900px;
    color: var(--text-muted);
}

/* --- EXPERIENCE TIMELINE --- */
.timeline {
    margin-top: 20px;
    border-top: 1px solid var(--border);
}

.entry {
    display: grid;
    grid-template-columns: 280px 1fr;
    padding: 30px 0;
    border-bottom: 1px solid var(--border);
}

.entry-date {
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 2px;
}

.entry-body h3 {
    font-size: 2.2rem;
    font-weight: 900;
    margin: 0 0 10px 0;
    letter-spacing: -1px;
    color: var(--primary);
}

.company-header {
    display: flex;
    align-items: center;
    margin-bottom: 30px;
}

.company-logo {
    height: 32px;
    width: auto;
    margin-right: 15px;
    object-fit: contain;
}

.entry-company {
    font-size: 1.2rem;
    color: var(--text-muted);
    display: block;
}

.entry-list {
    list-style: none;
    padding: 0;
    max-width: 800px;
}

.entry-list li {
    position: relative;
    padding-left: 30px;
    margin-bottom: 18px;
    font-size: 1.1rem;
    color: var(--text-muted);
}

.entry-list li::before {
    content: "—";
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: bold;
}

/* --- EXPERTISE & INTERESTS GRID --- */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-top: 20px;
}

.skill-item h4 {
    font-size: 1.2rem;
    font-weight: 900;
    margin-bottom: 10px;
    text-transform: uppercase;
    color: var(--primary);
}

.skill-item p { 
    color: var(--text-muted); 
    font-size: 1rem; 
}

.skill-item ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.skill-item ul li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 8px;
    color: var(--text-muted);
    font-size: 1rem;
}

.skill-item ul li::before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: bold;
}

.lab-card {
    background: var(--card-bg);
    padding: 20px 40px; 
    border-radius: 4px;
    transition: all 0.3s ease;
    border: 1px solid transparent;
}

.lab-card:hover {
    background: var(--card-hover);
    border-color: var(--border);
    box-shadow: 0 20px 40px rgba(0,0,0,0.05);
}

footer {
    padding: 30px 0;
    background: #000;
    color: #fff;
}

.footer-main {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-logo { font-weight: 900; font-size: 1.5rem; letter-spacing: -1px; }
.footer-contact a { color: #fff; text-decoration: none; margin-left: 20px; }
.footer-contact a:hover { color: var(--accent); }

.footer-meta {
    font-size: 0.75rem;
    color: #4b5563;
    text-transform: uppercase;
    letter-spacing: 1px;
    border-top: 1px solid #1f2937;
    padding-top: 20px;
    width: 100%;
    text-align: center;
    margin-top: 20px;
}

/* --- RESPONSIVE --- */
@media (max-width: 1100px) {
    .hero-grid { grid-template-columns: 1fr; text-align: center; }
    .avatar-box { justify-content: center; margin-top: 40px; }
    .profile-pic { width: 300px; height: 300px; } 
    .entry { grid-template-columns: 1fr; padding: 30px 0; }
    .btn-group { justify-content: center; }
    .footer-main { flex-direction: column; gap: 30px; }
    .nav-links { display: none; }
}