/* --- CSS VARIABLES & RESET --- */
:root {
    --bg-color: #0f172a; /* Dark Slate */
    --bg-secondary: #1e293b; /* Lighter Slate */
    --text-main: #f1f5f9; /* Off-white */
    --text-muted: #94a3b8; /* Slate 400 */
    --accent-color: #34d399; /* Emerald 400 */
    --accent-hover: #10b981;
    --border-color: #334155;
    --max-width: 1100px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* --- UTILITIES --- */
.container {
    width: 90%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 1rem;
}

h1, h2, h3, h4 {
    color: var(--text-main);
    font-weight: 700;
    line-height: 1.2;
}

p {
    color: var(--text-muted);
    margin-bottom: 1rem;
}

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

.section-padding {
    padding: 5rem 0;
}

/* --- BUTTONS --- */
.btn {
    display: inline-block;
    padding: 0.875rem 1.5rem;
    border-radius: 6px;
    font-weight: 500;
    font-size: 0.95rem;
    cursor: pointer;
    transition: var(--transition);
    border: 1px solid transparent;
}

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

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
}

.btn-outline {
    background-color: transparent;
    border-color: var(--text-main);
    color: var(--text-main);
}

.btn-outline:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
    background-color: rgba(5, 150, 105, 0.05);
}

/* --- NAVIGATION --- */
nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(15, 23, 42, 0.9);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 700;
    font-size: 1.1rem;
    letter-spacing: -0.02em;
    color: var(--text-main);
}

.logo img {
    height: 32px;
    width: auto;
    border-radius: 6px;
}

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

.nav-links a {
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-muted);
}

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

/* --- HERO SECTION --- */
.hero {
    min-height: 90vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
    padding-top: 70px; /* Offset for fixed nav */
}

.hero .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 3rem;
}

/* Subtle Network Background Pattern */
.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background-image: 
        radial-gradient(circle at 70% 30%, rgba(52, 211, 153, 0.15) 0%, transparent 40%),
        radial-gradient(var(--border-color) 1px, transparent 1px);
    background-size: 100% 100%, 40px 40px;
    opacity: 0.8;
    mask-image: linear-gradient(to bottom, black 80%, transparent 100%);
    -webkit-mask-image: linear-gradient(to bottom, black 80%, transparent 100%);
}

.hero-content {
    max-width: 700px;
}

.hero h1 {
    font-size: 3.5rem;
    letter-spacing: -0.03em;
    margin-bottom: 1rem;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--accent-color);
    font-weight: 600;
    margin-bottom: 1.5rem;
    display: block;
}

.hero-intro {
    font-size: 1.125rem;
    margin-bottom: 2.5rem;
    max-width: 600px;
}

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

.hero-image-wrapper {
    flex: 1;
    display: flex;
    justify-content: center;
    position: relative;
}

.profile-img {
    width: 100%;
    max-width: 380px;
    border-radius: 24px;
    border: 1px solid var(--border-color);
    box-shadow: 0 0 40px rgba(52, 211, 153, 0.1);
}

/* --- GRID LAYOUTS --- */
.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2.5rem;
}

.grid-4 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 2rem;
}

/* --- WHAT I WORK ON --- */
.feature-card {
    padding: 2rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    transition: var(--transition);
}

.feature-card:hover {
    border-color: var(--accent-color);
    box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.05);
}

.icon-box {
    width: 48px;
    height: 48px;
    background: rgba(5, 150, 105, 0.1);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    color: var(--accent-color);
}

.feature-card h3 {
    margin-bottom: 0.75rem;
    font-size: 1.25rem;
}

/* --- BACKGROUND SECTION --- */
.bg-section {
    background-color: var(--bg-secondary);
}

.split-layout {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 4rem;
    align-items: center;
}

.timeline-list {
    list-style: none;
    border-left: 2px solid var(--border-color);
    padding-left: 2rem;
}

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

.timeline-item::before {
    content: '';
    position: absolute;
    left: -2.4rem; /* Adjust based on border width and padding */
    top: 6px;
    width: 12px;
    height: 12px;
    background: var(--bg-color);
    border: 2px solid var(--accent-color);
    border-radius: 50%;
}

.timeline-item h4 {
    font-size: 1.1rem;
    margin-bottom: 0.25rem;
}

.timeline-item span {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* --- HOW I WORK (CARDS) --- */
.service-card {
    background: var(--bg-secondary);
    padding: 2.5rem;
    border-radius: 12px;
    text-align: center;
    transition: var(--transition);
}

.service-card:hover {
    transform: translateY(-5px);
    background: #334155;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

.service-card h3 {
    margin-bottom: 1rem;
    color: var(--text-main);
}

/* --- CONTACT --- */
.contact-section {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.contact-section h2 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
}

.contact-section p {
    font-size: 1.125rem;
    margin-bottom: 2.5rem;
}

/* --- FOOTER --- */
footer {
    padding: 2rem 0;
    border-top: 1px solid var(--border-color);
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* --- RECOGNITION SECTION --- */
.recognition-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.recognition-card {
    background: var(--bg-secondary);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.recognition-card:hover {
    border-color: var(--accent-color);
    transform: translateY(-3px);
}

.recognition-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.recognition-type {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--accent-color);
    background: rgba(52, 211, 153, 0.1);
    padding: 0.25rem 0.75rem;
    border-radius: 999px;
    font-weight: 600;
}

.recognition-year {
    font-size: 0.9rem;
    color: var(--text-muted);
    font-family: monospace;
}

/* --- TALKS SECTION --- */
.talk-card {
    display: block;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    overflow: hidden;
    transition: var(--transition);
    height: 100%;
}

.talk-card:hover {
    transform: translateY(-5px);
    border-color: var(--accent-color);
    box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.2);
}

.talk-thumbnail {
    position: relative;
    padding-top: 56.25%; /* 16:9 aspect ratio */
    background-color: var(--bg-color);
    overflow: hidden;
}

.talk-thumbnail img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.talk-thumbnail iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 0;
}

.talk-card:hover .talk-thumbnail img {
    transform: scale(1.05);
}

.talk-content {
    padding: 1.5rem;
}

/* --- ANIMATIONS --- */
.fade-in-section {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
    will-change: opacity, visibility;
}

.fade-in-section.is-visible {
    opacity: 1;
    transform: none;
}

/* --- RESPONSIVE --- */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .split-layout {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .nav-links {
        display: none; /* Simple hide for mobile MVP */
    }
    
    .hero-actions {
        flex-direction: column;
    }

    .hero .container {
        flex-direction: column-reverse;
        text-align: center;
    }
    
    .btn {
        width: 100%;
        text-align: center;
    }
}