* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
/* 1. Hide the element by default (Mobile view) */
.desktop-only {
    display: none !important; 
}

/* 2. Show the element when the screen width is 768 pixels or larger (PC/Tablet view) */
@media (min-width: 768px) {
    .desktop-only {
        display: block !important; /* Use 'flex' instead of 'block' if it's a flex container */
    }
}
:root {
    --primary-color: #1a73e8;
    --secondary-color: #34a853;
    --text-dark: #202124;
    --text-light: #5f6368;
    --bg-light: #f8f9fa;
    --bg-white: #ffffff;
    --border-color: #dadce0;
    --shadow: 0 4px 24px rgba(44, 62, 80, 0.08);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
    font-size: 18px;
}

/* Navbar */
.navbar {
    background-color: var(--bg-white);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--border-color);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    font-size: 24px;
    font-weight: 600;
    color: var(--primary-color);
    text-decoration: none;
    letter-spacing: 1px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-link {
    color: var(--text-dark);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

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

/* =========================================
   HERO & HEADER SECTIONS (UPDATED WITH DOODLES)
   ========================================= */

/* Hero Section (Home Page - General HEP Doodle) */
.hero {
    background: url('images/hep-doodle.svg'), linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    background-size: 450px, cover; 
    background-position: center;
    background-repeat: repeat, no-repeat;
    color: white;
    padding: 100px 20px;
    text-align: center;
    min-height: 500px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-content h1 {
    font-size: 56px;
    margin-bottom: 20px;
    font-weight: 700;
}

.subtitle {
    font-size: 24px;
    margin-bottom: 40px;
    opacity: 0.9;
}

.social-links {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
}

.social-links a {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background-color: rgba(255, 255, 255, 0.2);
    color: white;
    padding: 12px 24px;
    border-radius: 25px;
    text-decoration: none;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.social-links a:hover {
    background-color: white;
    color: #667eea;
    border-color: white;
}

/* Base Page Header */
.page-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    background-size: 450px, cover;
    background-position: center;
    background-repeat: repeat, no-repeat;
    color: white;
    padding: 60px 20px;
    text-align: center;
}

.page-header h1 {
    font-size: 48px;
    font-weight: 700;
}

/* Subpage Modifier Classes for Doodles */
.page-header.header-education {
    background: url('images/education-doodle.svg'), linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.page-header.header-experience {
    background: url('images/bsm-doodle.svg'), linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.page-header.header-fun {
    background: url('images/strings-doodle.svg'), linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.page-header.header-contact {
    /* Updated to use your new.svg file instead of the old neutrino one! */
    background: url('images/new.svg'), linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

/* =========================================
   REMAINING CONTENT STYLES
   ========================================= */

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Content Section */
.content-section {
    padding: 80px 20px;
    background-color: var(--bg-light);
}

/* Welcome Section */
.welcome {
    padding: 80px 20px;
    background-color: var(--bg-light);
}

.welcome h2 {
    font-size: 40px;
    margin-bottom: 30px;
    color: var(--primary-color);
    text-align: center;
}

.welcome p {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-light);
    max-width: 900px;
    margin: 0 auto 20px;
    text-align: center;
}

.quick-links {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 40px;
}

/* Random Content Section */
.random-content {
    padding: 80px 20px;
    background-color: var(--bg-white);
}

.random-content h2 {
    font-size: 40px;
    margin-bottom: 30px;
    color: var(--primary-color);
    text-align: center;
}

.random-content p {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-light);
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

/* Education Content */
.education-content h2 {
    font-size: 32px;
    color: var(--primary-color);
    margin-top: 40px;
    margin-bottom: 25px;
}

.education-content h2:first-child {
    margin-top: 0;
}

.education-item {
    background-color: var(--bg-white);
    padding: 30px;
    border-radius: 8px;
    margin-bottom: 25px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.education-item h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 22px;
}

.education-item .subtitle {
    color: var(--text-light);
    font-size: 16px;
    margin-bottom: 15px;
    opacity: 1;
}

.education-item p {
    color: var(--text-light);
    line-height: 1.8;
    margin-bottom: 10px;
}

.interest-list {
    list-style: none;
    margin-left: 0;
}

.interest-list li {
    padding: 8px 0;
    padding-left: 25px;
    position: relative;
    color: var(--text-light);
}

.interest-list li:before {
    content: "▸";
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.project-card {
    background-color: var(--bg-white);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.project-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.12);
}

.project-card h3 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 22px;
}

.project-description {
    color: var(--text-light);
    margin-bottom: 20px;
    line-height: 1.8;
}

.project-details {
    background-color: var(--bg-light);
    padding: 15px;
    border-radius: 4px;
    margin-bottom: 20px;
}

.project-details p {
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 8px;
}

.project-details p:last-child {
    margin-bottom: 0;
}

/* Fun Items - Alternating Pattern */
.fun-item {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
    margin-bottom: 60px;
    background-color: var(--bg-white);
    padding: 40px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.fun-item-left, .fun-item-right {
    grid-template-columns: 1fr 1fr;
}

.fun-item-right .fun-image {
    order: 2;
}

.fun-item-right .fun-text {
    order: 1;
}

.fun-image {
    overflow: hidden;
    border-radius: 8px;
}

.fun-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.fun-image:hover img {
    transform: scale(1.05);
}

.fun-text h3 {
    color: var(--primary-color);
    font-size: 28px;
    margin-bottom: 15px;
}

.fun-text p {
    color: var(--text-light);
    line-height: 1.8;
    font-size: 16px;
}

/* Contact Section */
.contact-info-section h2,
.cv-section h2,
.message-section h2 {
    font-size: 32px;
    color: var(--primary-color);
    margin-bottom: 30px;
    margin-top: 50px;
}

.contact-info-section h2:first-child,
.cv-section h2:first-child {
    margin-top: 0;
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.contact-item {
    background-color: var(--bg-white);
    padding: 30px;
    border-radius: 8px;
    text-align: center;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease;
}

.contact-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.12);
}

.contact-item i {
    font-size: 40px;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.contact-item h3 {
    margin-bottom: 10px;
    color: var(--text-dark);
    font-size: 20px;
}

.contact-item a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.3s ease;
    word-break: break-word;
}

.contact-item a:hover {
    color: #1557b0;
    text-decoration: underline;
}

.contact-item p {
    color: var(--text-light);
}

/* CV Box */
.cv-box {
    background-color: var(--bg-white);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.cv-box p {
    color: var(--text-light);
    margin-bottom: 20px;
    line-height: 1.8;
}

/* Contact Form */
.contact-form {
    background-color: var(--bg-white);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    max-width: 600px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-dark);
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-family: inherit;
    font-size: 16px;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.1);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 32px;
    border-radius: 4px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 16px;
}

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

.btn-primary:hover {
    background-color: #1557b0;
    box-shadow: 0 4px 12px rgba(26, 115, 232, 0.4);
}

.btn-secondary {
    background-color: var(--secondary-color);
    color: white;
}

.btn-secondary:hover {
    background-color: #2d8659;
    box-shadow: 0 4px 12px rgba(52, 168, 83, 0.4);
}

/* Footer */
.footer {
    background-color: var(--text-dark);
    color: white;
    text-align: center;
    padding: 40px 20px;
}

.footer p {
    margin-bottom: 10px;
}

.footer p:last-child {
    margin-bottom: 0;
}

.last-updated {
    font-size: 14px;
    opacity: 0.8;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        gap: 15px;
        font-size: 14px;
    }

    .hero-content h1 {
        font-size: 36px;
    }

    .subtitle {
        font-size: 18px;
    }

    .page-header h1 {
        font-size: 32px;
    }

    .welcome h2,
    .random-content h2,
    .education-content h2,
    .contact-info-section h2,
    .cv-section h2,
    .message-section h2 {
        font-size: 28px;
    }

    .social-links {
        flex-direction: column;
    }

    .social-links a {
        width: 100%;
    }

    .quick-links {
        flex-direction: column;
    }

    .quick-links .btn {
        width: 100%;
        justify-content: center;
    }

    .fun-item {
        grid-template-columns: 1fr;
        gap: 20px;
        padding: 20px;
    }

    .fun-item-right .fun-image {
        order: 0;
    }

    .fun-item-right .fun-text {
        order: 0;
    }

    .contact-form {
        padding: 20px;
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .nav-menu {
        gap: 10px;
        font-size: 12px;
    }

    .hero-content h1 {
        font-size: 28px;
    }

    .page-header h1 {
        font-size: 24px;
    }

    .btn {
        padding: 10px 20px;
        font-size: 14px;
    }

    .education-item,
    .project-card,
    .fun-item {
        padding: 20px;
    }

    .fun-text h3 {
        font-size: 22px;
    }

    .contact-item i {
        font-size: 32px;
    }
}