/* --- Global Styles & Variables --- */
:root {
    --bg-color: #0f172a;
    --primary-text: #e2e8f0;
    --secondary-text: #94a3b8;
    --highlight-color: #22d3ee;
    --card-bg: rgba(30, 41, 59, 0.5); /* Slightly more opaque for better readability */
    --card-border: rgba(51, 65, 85, 0.7);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    background-color: var(--bg-color);
    color: var(--primary-text);
    background-image: radial-gradient(circle at top right, rgba(14, 165, 233, 0.2), transparent 45%);
    line-height: 1.6;
}

/* --- Utility & Global Classes --- */
.content-section {
    padding: 6rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
    opacity: 0; /* For scroll animation */
    transform: translateY(20px); /* For scroll animation */
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.content-section.visible {
    opacity: 1;
    transform: translateY(0);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 4rem;
    font-weight: 600;
    color: var(--primary-text);
    position: relative;
    display: inline-block;
    left: 50%;
    transform: translateX(-50%);
}

.section-title::after {
    content: '';
    position: absolute;
    width: 60%;
    height: 3px;
    background: var(--highlight-color);
    border-radius: 5px;
    bottom: -10px;
    left: 20%;
}

/* --- Header & Navigation --- */
header {
    position: fixed;
    width: 100%;
    top: 0;
    left: 0;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--card-border);
}

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

nav .logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-text);
    text-decoration: none;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 2rem;
}

nav a {
    color: var(--primary-text);
    text-decoration: none;
    font-size: 1rem;
    transition: color 0.3s ease;
    padding: 0.5rem 0;
    position: relative;
}

nav a:hover {
    color: var(--highlight-color);
}

nav a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: 0;
    left: 0;
    background-color: var(--highlight-color);
    transition: width 0.3s ease;
}

nav a:hover::after {
    width: 100%;
}


/* --- Hero Section --- */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    padding: 6rem 2rem 2rem; /* Added padding top for header */
    gap: 2rem;
}

.hero-text {
    max-width: 600px;
}

.hero-text p {
    font-size: 1.5rem;
}

.hero-text h1 {
    font-size: clamp(2.5rem, 5vw, 4rem); /* Responsive font size */
    margin: 0.5rem 0;
}

.hero-text h1 span {
    color: var(--highlight-color);
}

.hero-text h2 {
    font-size: clamp(1.2rem, 3vw, 1.5rem); /* Responsive font size */
    font-weight: 400;
    color: var(--secondary-text);
}

.hero-image {
    width: 300px;
    height: 300px;
    min-width: 250px;
    border-radius: 50%;
    overflow: hidden;
    border: 5px solid transparent;
    background: linear-gradient(var(--bg-color), var(--bg-color)) padding-box,
                linear-gradient(45deg, #38bdf8, #6366f1) border-box;
    animation: pulse-border 5s infinite;
}

@keyframes pulse-border {
    0% { box-shadow: 0 0 0 0 rgba(34, 211, 238, 0.7); }
    70% { box-shadow: 0 0 0 15px rgba(34, 211, 238, 0); }
    100% { box-shadow: 0 0 0 0 rgba(34, 211, 238, 0); }
}

.hero-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* --- About Section --- */
.about-container {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 15px;
    padding: 2.5rem;
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
    font-size: 1.1rem;
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
}

/* --- Education Timeline (NEW) --- */
.timeline {
    position: relative;
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem 0;
}

.timeline::after {
    content: '';
    position: absolute;
    width: 3px;
    background-color: var(--card-border);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -1.5px;
    z-index: -1;
}

.timeline-item {
    padding: 10px 0;
    position: relative;
    width: 50%;
    display: flex;
    align-items: center;
}

.timeline-item:nth-child(odd) {
    left: 0;
    justify-content: flex-end;
    padding-right: 80px;
}

.timeline-item:nth-child(even) {
    left: 50%;
    justify-content: flex-start;
    padding-left: 80px;
}

.timeline-node {
    width: 80px;
    height: 80px;
    background-color: var(--bg-color);
    border: 3px solid var(--highlight-color);
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    border-radius: 50%;
    z-index: 1;
    display: grid;
    place-items: center;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.timeline-node:hover {
    transform: translateY(-50%) scale(1.1);
    box-shadow: 0 0 20px var(--highlight-color);
}

.timeline-node img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.timeline-item:nth-child(odd) .timeline-node {
    right: -40px;
}

.timeline-item:nth-child(even) .timeline-node {
    left: -40px;
}

.timeline-content {
    padding: 20px 30px;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    position: relative;
    border-radius: 10px;
    width: 100%;
    max-width: 350px;
}

.timeline-item:nth-child(odd) .timeline-content {
    text-align: right;
}

.timeline-content::before {
    content: ' ';
    height: 2px;
    width: 50px;
    background-color: var(--card-border);
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    z-index: -1;
}

.timeline-item:nth-child(odd) .timeline-content::before {
    right: -50px;
}

.timeline-item:nth-child(even) .timeline-content::before {
    left: -50px;
}


/* --- Skills Section --- */
.skills-container {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.skill-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    color: var(--primary-text);
    padding: 2rem;
    border-radius: 10px;
    min-width: 300px;
    border-left: 4px solid var(--highlight-color);
}

.skill-card h3 {
    margin-bottom: 1rem;
    font-size: 1.5rem;
    color: var(--highlight-color);
}

.skill-card ul {
    list-style-type: '✓  ';
    padding-left: 1.5rem;
}

.skill-card li {
    margin-bottom: 0.5rem;
}

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

.project-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 10px;
    overflow: hidden;
    text-align: center;
    text-decoration: none;
    color: var(--primary-text);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 20px rgba(34, 211, 238, 0.2);
}

.project-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-bottom: 1px solid var(--card-border);
}

.project-card p {
    padding: 1.5rem 1rem;
    font-weight: 500;
    font-size: 1.1rem;
}

/* --- Contact Section --- */
.contact-container {
    display: flex;
    justify-content: center;
    gap: 4rem;
    text-align: center;
    flex-wrap: wrap;
}

.contact-item .icon-circle {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: linear-gradient(45deg, #38bdf8, #6366f1);
    display: grid;
    place-items: center;
    font-size: 1.8rem;
    margin: 0 auto 1rem;
}

.contact-item h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.contact-item a {
    color: var(--secondary-text);
    text-decoration: none;
    transition: color 0.3s ease;
}
.contact-item a:hover {
    color: var(--highlight-color);
}

/* --- Footer --- */
footer {
    padding: 4rem 2rem 2rem;
    text-align: center;
    background: rgba(0,0,0,0.2);
    border-top: 1px solid var(--card-border);
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.social-item a {
    text-decoration: none;
    color: var(--primary-text);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    transition: color 0.3s ease;
}

.social-item a:hover {
    color: var(--highlight-color);
}

.social-icon {
    width: 30px;
    height: 30px;
    filter: invert(0.85); /* Makes PNG icons light gray */
    transition: filter 0.3s ease;
}

.social-item a:hover .social-icon {
    filter: invert(0.6) sepia(1) saturate(5) hue-rotate(150deg);
}

.social-item a span {
    color: var(--secondary-text);
    font-size: 0.9rem;
}

.copyright {
    margin-top: 2rem;
    font-size: 0.9rem;
    color: var(--secondary-text);
}


/* --- Responsive Design --- */

/* For Tablets */
@media (max-width: 900px) {
    .timeline::after {
        left: 40px; /* Move vertical line to the left */
    }
    .timeline-item {
        width: 100%;
        padding-left: 100px;
        padding-right: 25px;
    }
    .timeline-item:nth-child(even), .timeline-item:nth-child(odd) {
        left: 0;
        justify-content: flex-start;
    }
    .timeline-node {
        left: 0;
    }
    .timeline-content {
        text-align: left !important;
    }
    .timeline-content::before {
        left: -50px;
    }
}


/* For Mobile Phones */
@media (max-width: 768px) {
    nav ul {
        display: none; /* In a real project, you'd add a hamburger menu here */
    }
    .hero {
        flex-direction: column;
        text-align: center;
        padding-top: 8rem;
    }
    .hero-text {
        order: 2;
    }
    .hero-image {
        order: 1;
        width: 200px;
        height: 200px;
        margin-bottom: 2rem;
    }

    .skills-container {
        flex-direction: column;
        align-items: center;
    }
}