/* CSS Variables for Theme Switching */
:root {
    --bg-color: #ffffff;
    --bg-alt: #f8f9fa;
    --text-color: #2d3436;
    --text-light: #636e72;
    --primary: #2980b9;
    --primary-hover: #3498db;
    --accent: #e17055;
    --border: #e0e0e0;
    --card-bg: #ffffff;
    --shadow: 0 4px 6px rgba(0,0,0,0.05);
    --nav-bg: rgba(255, 255, 255, 0.95);
}

[data-theme="dark"] {
    --bg-color: #0a192f;
    --bg-alt: #112240;
    --text-color: #ccd6f6;
    --text-light: #8892b0;
    --primary: #64ffda;
    --primary-hover: #4adbc0;
    --accent: #64ffda;
    --border: #233554;
    --card-bg: #112240;
    --shadow: 0 4px 15px rgba(0,0,0,0.3);
    --nav-bg: rgba(10, 25, 47, 0.95);
}

/* Global Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s ease, color 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

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

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    display: block;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Buttons */
.btn-primary {
    background-color: transparent;
    color: var(--primary);
    border: 1px solid var(--primary);
    padding: 0.75rem 1.5rem;
    border-radius: 4px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-primary:hover {
    background-color: rgba(41, 128, 185, 0.1);
}

[data-theme="dark"] .btn-primary:hover {
    background-color: rgba(100, 255, 218, 0.1);
}

.btn-secondary {
    color: var(--text-light);
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    transition: color 0.3s ease;
}

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

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    height: 80px;
    background-color: var(--nav-bg);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--border);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

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

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

.nav-links a {
    font-size: 0.9rem;
    font-weight: 500;
}

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

/* Dark Mode Toggle */
#theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-color);
    margin-left: 20px;
}

.sun-icon { display: none; }
.moon-icon { display: block; }

[data-theme="dark"] .sun-icon { display: block; }
[data-theme="dark"] .moon-icon { display: none; }

/* Hero Section */
.hero {
    padding-top: 150px;
    padding-bottom: 100px;
    min-height: 90vh;
    display: flex;
    align-items: center;
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-text .greeting {
    color: var(--primary);
    font-weight: 600;
    font-size: 1.1rem;
    display: block;
    margin-bottom: 1rem;
}

.hero-text h1 {
    font-size: 4rem;
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 1rem;
}

.hero-text h2 {
    font-size: 2rem;
    color: var(--text-light);
    margin-bottom: 1.5rem;
}

.hero-text p {
    color: var(--text-light);
    max-width: 500px;
    margin-bottom: 2rem;
    font-size: 1.1rem;
}

.hero-btns {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.contact-mini {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    color: var(--text-light);
    font-size: 0.9rem;
}

.hero-image {
    position: relative;
}

.hero-image img {
    border-radius: 50%;
    border: 4px solid var(--primary);
    width: 350px;
    height: 350px;
    object-fit: cover;
    margin: 0 auto;
    box-shadow: var(--shadow);
}

/* Sections */
.section {
    padding: 100px 0;
}

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

.section-title {
    font-size: 2rem;
    margin-bottom: 3rem;
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    width: 60%;
    height: 4px;
    background-color: var(--primary);
    bottom: -10px;
    left: 0;
    border-radius: 2px;
}

/* About */
.about-content {
    max-width: 800px;
}

.about-content p {
    margin-bottom: 1.5rem;
    color: var(--text-light);
}

/* Experience Timeline */
.timeline {
    position: relative;
    max-width: 800px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 2px;
    background-color: var(--border);
}

.timeline-item {
    position: relative;
    padding-left: 30px;
    margin-bottom: 3rem;
}

.timeline-dot {
    position: absolute;
    left: -4px;
    top: 5px;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--primary);
}

.job-header h3 {
    font-size: 1.5rem;
    color: var(--primary);
}

.project-header {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    margin-bottom: 0.5rem;
}

.timeline-content h3 {
    font-size: 1.2rem;
    font-weight: 600;
}

.timeline-content .date {
    font-size: 0.85rem;
    font-family: monospace;
    color: var(--text-light);
}

.timeline-content p {
    color: var(--text-light);
    margin: 0.5rem 0 1rem 0;
}

.timeline-content ul {
    list-style: disc;
    margin-left: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-light);
}

.timeline-content li {
    margin-bottom: 0.5rem;
}

.tech-stack span {
    display: inline-block;
    font-size: 0.75rem;
    background-color: var(--bg-alt);
    color: var(--primary);
    padding: 0.2rem 0.6rem;
    border-radius: 15px;
    margin-right: 5px;
    margin-bottom: 5px;
    border: 1px solid var(--border);
}

/* Skills */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.skill-category h3 {
    margin-bottom: 1rem;
    color: var(--text-color);
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem;
}

.skill-tags span {
    background-color: var(--card-bg);
    padding: 0.5rem 1rem;
    border-radius: 4px;
    box-shadow: var(--shadow);
    font-size: 0.9rem;
    border: 1px solid var(--border);
}

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

.edu-card {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
}

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

.edu-card.cert {
    border-left: 4px solid var(--primary);
}

/* Footer */
footer {
    text-align: center;
    padding: 100px 0 50px;
    background-color: var(--bg-alt);
}

.footer-content h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.footer-content p {
    color: var(--text-light);
    max-width: 500px;
    margin: 0 auto 3rem;
}

.contact-links {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
}

.copyright {
    font-size: 0.8rem;
    margin-top: 2rem;
}

/* Responsive */
.hamburger { display: none; }

@media (max-width: 768px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-btns {
        justify-content: center;
    }

    .hero-image img {
        width: 250px;
        height: 250px;
    }

    .hero-text h1 {
        font-size: 2.5rem;
    }

    .hamburger {
        display: flex;
        flex-direction: column;
        gap: 5px;
        cursor: pointer;
    }
    
    .hamburger span {
        width: 25px;
        height: 3px;
        background-color: var(--text-color);
    }

    .nav-links {
        position: absolute;
        top: 80px;
        right: 0;
        height: 0;
        width: 100%;
        background-color: var(--nav-bg);
        flex-direction: column;
        overflow: hidden;
        transition: height 0.3s ease;
        border-bottom: 1px solid var(--border);
    }

    .nav-links.active {
        height: 320px;
        padding: 20px 0;
    }
}

/* Animation Utility */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}