/* Base & CSS Variables */
:root {
    /* Light Mode Premium Palette */
    --primary: #4F46E5;
    --primary-light: #6366F1;
    --secondary: #10B981;
    --dark: #111827;
    --text-main: #1F2937;
    --text-muted: #6B7280;
    --bg-main: #FFFFFF;
    --bg-alt: #F9FAFB;
    --border: #E5E7EB;
    
    /* Typography */
    --font-sans: 'Inter', sans-serif;
    --font-heading: 'Outfit', sans-serif;
    
    /* Shadows for depth */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-hover: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    /* Transitions */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    color: var(--text-main);
    background-color: var(--bg-main);
    line-height: 1.6;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    color: var(--dark);
    line-height: 1.2;
}

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

ul {
    list-style: none;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.section {
    padding: 6rem 0;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    text-align: center;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--primary);
    border-radius: 2px;
}

.text-center {
    text-align: center;
}

.bg-light {
    background-color: var(--bg-alt);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
}

.btn-primary {
    background-color: var(--primary);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background-color: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    color: white;
}

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

.btn-secondary:hover {
    border-color: var(--primary);
    background-color: rgba(79, 70, 229, 0.05);
    transform: translateY(-2px);
}

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

.btn-outline:hover {
    background-color: var(--dark);
    color: white;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

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

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

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

.hamburger {
    display: none;
    cursor: pointer;
    font-size: 1.5rem;
    color: var(--dark);
}

/* Hero Section */
.hero {
    min-height: 100vh;
    position: relative;
    overflow: hidden;
}

.hero-container {
    display: flex;
    align-items: center;
    padding: 0 2rem;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
    min-height: 100vh;
}

.hero-video-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: -2;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(10, 15, 25, 0.65); /* Dark frosty overlay for contrast */
    backdrop-filter: blur(5px);
    -webkit-backdrop-filter: blur(5px);
    z-index: -1;
}

.hero-content {
    flex: 1;
    z-index: 2;
    padding-top: 5rem;
}

.greeting {
    font-size: 1.25rem;
    color: #60a5fa; /* Vibrant bright blue */
    font-weight: 600;
    margin-bottom: 0.5rem;
    text-shadow: 0 2px 4px rgba(0,0,0,0.5);
}

.name {
    font-size: 4rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: #ffffff;
    text-shadow: 0 2px 8px rgba(0,0,0,0.7);
}

.title {
    font-size: 2rem;
    color: #f3f4f6;
    font-weight: 400;
    margin-bottom: 1.5rem;
    text-shadow: 0 2px 4px rgba(0,0,0,0.6);
}

.bio {
    font-size: 1.125rem;
    color: #d1d5db;
    max-width: 600px;
    margin-bottom: 2rem;
    line-height: 1.6;
    text-shadow: 0 2px 4px rgba(0,0,0,0.6);
}

.cta-group {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

/* Skills & Tools Section */
.skills-section {
    padding: 6rem 0;
    background: #ffffff;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.skill-category-card {
    background: #ffffff;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 1px solid var(--border);
}

.skill-category-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    border-color: var(--primary);
}

.skill-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.skill-header i {
    font-size: 1.5rem;
    color: var(--primary);
}

.skill-header h3 {
    margin: 0;
    font-size: 1.25rem;
    color: var(--dark);
}

.tools-container {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tool-tag {
    background: #f1f5f9;
    color: var(--text);
    padding: 0.4rem 0.8rem;
    border-radius: 2rem;
    font-size: 0.875rem;
    font-weight: 500;
    border: 1px solid #e2e8f0;
    transition: all 0.2s ease;
    cursor: help;
    position: relative;
}

.tool-tag:hover {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.tool-tag[data-tooltip]:hover::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    background: #1e293b;
    color: white;
    padding: 0.4rem 0.75rem;
    border-radius: 6px;
    font-size: 0.75rem;
    white-space: normal;
    width: max-content;
    max-width: 250px;
    text-align: center;
    margin-bottom: 8px;
    z-index: 1000;
    pointer-events: none;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    line-height: 1.4;
    font-weight: 400;
    letter-spacing: 0.3px;
}

.tool-tag[data-tooltip]:hover::before {
    content: '';
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    border-width: 6px;
    border-style: solid;
    border-color: #1e293b transparent transparent transparent;
    margin-bottom: -4px;
    z-index: 1000;
    pointer-events: none;
}

/* Abstract Visuals */
.hero-visual {
    flex: 1;
    position: relative;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2;
}

.abstract-shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(60px);
    z-index: 1;
    opacity: 0.6;
}

.shape-1 {
    width: 300px;
    height: 300px;
    background: rgba(79, 70, 229, 0.4);
    top: 20%;
    right: 10%;
    animation: float 8s ease-in-out infinite;
}

.shape-2 {
    width: 250px;
    height: 250px;
    background: rgba(16, 185, 129, 0.3);
    bottom: 20%;
    left: 10%;
    animation: float 10s ease-in-out infinite reverse;
}

@keyframes float {
    0% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-30px) rotate(10deg); }
    100% { transform: translateY(0px) rotate(0deg); }
}

/* Projects Section */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.project-card {
    background: var(--bg-main);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    border: 1px solid var(--border);
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-hover);
}

.project-img-placeholder {
    height: 200px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.project-video {
    width: 100%;
    height: 200px;
    object-fit: contain;
    background-color: transparent;
    -webkit-mask-image: radial-gradient(closest-side, black 85%, transparent 100%);
    mask-image: radial-gradient(closest-side, black 85%, transparent 100%);
    display: block;
}

.project-img {
    width: 100%;
    height: 200px;
    object-fit: contain;
    background-color: transparent;
    -webkit-mask-image: radial-gradient(closest-side, black 85%, transparent 100%);
    mask-image: radial-gradient(closest-side, black 85%, transparent 100%);
    display: block;
}

.project-info {
    padding: 1.5rem;
}

.project-info h3 {
    margin-bottom: 0.5rem;
    font-size: 1.25rem;
}

.project-info p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 1.25rem;
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary);
    font-weight: 600;
    font-size: 0.95rem;
}

.project-link:hover {
    gap: 0.75rem;
}

/* CV Section */
.cv-section {
    background: var(--bg-main);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 3rem;
}

.section-header .section-title {
    margin-bottom: 0;
}

.section-header .section-title::after {
    left: 0;
    transform: none;
}

.timeline {
    position: relative;
    max-width: 100%;
    margin: 0 auto;
}

.timeline::after {
    content: '';
    position: absolute;
    width: 2px;
    background-color: var(--border);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -1px;
}

.timeline-item {
    padding: 10px 15px;
    position: relative;
    background-color: inherit;
    width: 50%;
}

.timeline-item:nth-child(odd) {
    left: 0;
}

.timeline-item:nth-child(even) {
    left: 50%;
}

.timeline-dot {
    position: absolute;
    width: 20px;
    height: 20px;
    right: -10px;
    background-color: var(--primary);
    border: 4px solid var(--bg-main);
    border-radius: 50%;
    top: 15px;
    z-index: 1;
}

.timeline-item:nth-child(even) .timeline-dot {
    left: -10px;
}

.timeline-content {
    padding: 20px 20px;
    background-color: var(--bg-alt);
    position: relative;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.timeline-item:hover .timeline-content {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.timeline-date {
    display: block;
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.timeline-content h3 {
    margin-bottom: 0.25rem;
}

.timeline-content h4 {
    color: var(--text-muted);
    font-weight: 500;
    margin-bottom: 1rem;
    font-size: 0.95rem;
}

/* Tabs */
.tabs-container {
    display: flex;
    justify-content: center;
    margin-bottom: 3rem;
}

.tabs {
    display: flex;
    background: var(--bg-alt);
    border-radius: 50px;
    padding: 0.5rem;
    box-shadow: var(--shadow-sm);
}

.tab-btn {
    background: transparent;
    border: none;
    padding: 0.75rem 2rem;
    border-radius: 50px;
    font-family: var(--font-sans);
    font-weight: 600;
    font-size: 1rem;
    color: var(--text-muted);
    cursor: pointer;
    transition: var(--transition);
}

.tab-btn:hover {
    color: var(--primary);
}

.tab-btn.active {
    background: var(--primary);
    color: white;
    box-shadow: var(--shadow-sm);
}

.tab-content {
    display: none;
    animation: fadeIn 0.5s ease;
}

.tab-content.active {
    display: block;
}

/* Profiles Section */
.profiles-grid {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.profile-card {
    background: var(--bg-main);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2rem;
    width: 250px;
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.profile-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary-light);
}

.profile-icon {
    width: 70px;
    height: 70px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 0 auto 1.5rem;
    font-size: 2rem;
    color: white;
    transition: var(--transition);
}

.profile-card:hover .profile-icon {
    transform: scale(1.1);
}

.linkedin { background: #0077b5; }
.scholar { background: #4285F4; }
.github { background: #333; }
.email { background: #e74c3c; }

.profile-card h3 {
    margin-bottom: 0.5rem;
}

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

/* Footer */
.footer {
    background: var(--dark);
    color: rgba(255, 255, 255, 0.7);
    padding: 2rem 0;
}

/* Animations */
.fade-in {
    opacity: 0;
    animation: fadeIn 1s forwards;
}

.slide-up {
    transform: translateY(30px);
    animation: slideUp 1s forwards;
}

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

@keyframes slideUp {
    to { transform: translateY(0); }
}

.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s ease-out;
}

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

/* Responsive */
@media (max-width: 992px) {
    .hero {
        flex-direction: column;
        text-align: center;
        justify-content: center;
    }
    
    .cta-group {
        justify-content: center;
    }
    
    .hero-visual {
        display: none;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .hamburger {
        display: block;
    }
    
    .name {
        font-size: 3rem;
    }
    
    .title {
        font-size: 1.5rem;
    }
    
    .timeline::after {
        left: 31px;
    }
    
    .timeline-item {
        width: 100%;
        padding-left: 70px;
        padding-right: 25px;
    }
    
    .timeline-item:nth-child(even) {
        left: 0%;
    }
    
    .timeline-dot {
        left: 21px;
    }
    
    .timeline-item:nth-child(even) .timeline-dot {
        left: 21px;
    }
    
    .section-header {
        flex-direction: column;
        gap: 1.5rem;
    }
}