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

:root {
    --green-50: #f0fdf4;
    --green-100: #dcfce7;
    --green-200: #bbf7d0;
    --green-300: #86efac;
    --green-400: #4ade80;
    --green-500: #22c55e;
    --green-600: #16a34a;
    --green-700: #15803d;
    --green-800: #166534;
    --green-900: #14532d;
    --white: #ffffff;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    line-height: 1.6;
    color: var(--green-900);
    background: linear-gradient(135deg, var(--green-50) 0%, var(--white) 50%, var(--green-50) 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--green-200);
    box-shadow: 0 2px 8px rgba(22, 163, 74, 0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.nav-container {
    position: relative;
}

.nav-links {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    padding: 1rem 0;
    flex-wrap: nowrap;
    overflow-x: visible;
    -webkit-overflow-scrolling: touch;
}

.nav-toggle {
    display: none;
    background: transparent;
    border: none;
    color: var(--green-700);
    font-size: 1.25rem;
    padding: 0.5rem;
    margin-right: 0.5rem;
    cursor: pointer;
}

.nav-links.open {
    display: flex;
}

.nav-links::-webkit-scrollbar {
    height: 4px;
}

.nav-links::-webkit-scrollbar-track {
    background: var(--green-100);
}

.nav-links::-webkit-scrollbar-thumb {
    background: var(--green-600);
    border-radius: 2px;
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 0.5rem;
    background: transparent;
    color: var(--green-700);
    cursor: pointer;
    transition: all 0.3s ease;
    white-space: nowrap;
    font-size: 0.95rem;
    font-weight: 500;
}

.nav-btn:hover {
    background: var(--green-100);
}

.nav-btn.active {
    background: var(--green-600);
    color: var(--white);
    box-shadow: 0 4px 12px rgba(22, 163, 74, 0.3);
}

.nav-btn i {
    width: 18px;
    height: 18px;
}

.nav-btn span {
    display: none;
}

.hero {
    padding: 3rem 0;
    background: linear-gradient(180deg, var(--white) 0%, var(--green-50) 100%);
}

.hero-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.profile-image-wrapper {
    position: relative;
    margin-bottom: 3rem;
}

.profile-image {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    overflow: hidden;
    border: 8px solid var(--green-600);
    box-shadow: 0 10px 30px rgba(22, 163, 74, 0.3);
}

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

.profile-badge {
    position: absolute;
    bottom: -1rem;
    left: 50%;
    transform: translateX(-50%);
    background: var(--green-600);
    color: var(--white);
    padding: 0.5rem 1.5rem;
    border-radius: 2rem;
    box-shadow: 0 4px 12px rgba(22, 163, 74, 0.4);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
}

.profile-badge i {
    width: 20px;
    height: 20px;
}

.professor-name {
    font-size: 2rem;
    font-weight: 600;
    color: var(--green-900);
    margin-bottom: 0.5rem;
}

.professor-title {
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--green-700);
    margin-bottom: 0.5rem;
}

.professor-department {
    font-size: 1rem;
    color: var(--green-600);
    margin-bottom: 0.25rem;
}

.professor-institution {
    font-size: 1rem;
    color: var(--green-600);
    margin-bottom: 2rem;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background: var(--green-100);
    color: var(--green-700);
    border-radius: 50%;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px rgba(22, 163, 74, 0.2);
}

.social-btn:hover {
    background: var(--green-600);
    color: var(--white);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(22, 163, 74, 0.3);
}

.social-btn i {
    width: 20px;
    height: 20px;
}

.main-content {
    padding: 3rem 0;
}

.content-section {
    margin-bottom: 4rem;
    scroll-margin-top: 80px;
}

.section-card {
    background: var(--white);
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: 0 4px 20px rgba(22, 163, 74, 0.1);
    border: 1px solid var(--green-100);
}

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

.section-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background: var(--green-100);
    border-radius: 0.5rem;
}

.section-icon i {
    width: 24px;
    height: 24px;
    color: var(--green-600);
}

.section-header h2 {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--green-900);
}

.about-text {
    font-size: 1rem;
    line-height: 1.8;
    color: var(--green-800);
}

.education-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.education-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1rem;
    background: var(--green-50);
    border-radius: 0.75rem;
    transition: all 0.3s ease;
}

.education-item:hover {
    background: var(--green-100);
}

.bullet {
    width: 8px;
    height: 8px;
    background: var(--green-600);
    border-radius: 50%;
    margin-top: 0.5rem;
    flex-shrink: 0;
}

.education-content h3 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--green-900);
    margin-bottom: 0.25rem;
}

.education-content .institution {
    font-size: 1rem;
    color: var(--green-700);
    margin-bottom: 0.25rem;
}

.education-content .year {
    font-size: 0.95rem;
    color: var(--green-600);
}

.research-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.research-item {
    padding: 1rem;
    border-left: 4px solid var(--green-600);
    background: var(--green-50);
    border-radius: 0 0.75rem 0.75rem 0;
    transition: all 0.3s ease;
}

.research-item:hover {
    background: var(--green-100);
}

.research-item h3 {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--green-900);
    margin-bottom: 0.5rem;
}

.research-item .journal {
    font-size: 0.95rem;
    color: var(--green-700);
    margin-bottom: 0.25rem;
}

.research-item .year {
    font-size: 0.9rem;
    color: var(--green-600);
}

.courses-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
}

.course-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: linear-gradient(135deg, var(--green-50) 0%, var(--green-100) 100%);
    border: 1px solid var(--green-200);
    border-radius: 0.75rem;
    transition: all 0.3s ease;
}

.course-item:hover {
    box-shadow: 0 4px 12px rgba(22, 163, 74, 0.15);
}

.course-number {
    width: 32px;
    height: 32px;
    background: var(--green-600);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    flex-shrink: 0;
}

.course-item p {
    font-size: 1rem;
    color: var(--green-900);
}

.achievements-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.achievement-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--green-50);
    border-radius: 0.75rem;
    transition: all 0.3s ease;
}

.achievement-item:hover {
    background: var(--green-100);
}

.achievement-item i {
    width: 20px;
    height: 20px;
    color: var(--green-600);
    flex-shrink: 0;
}

.achievement-item p {
    font-size: 1rem;
    color: var(--green-900);
}

.contact-card {
    background: linear-gradient(135deg, var(--green-600) 0%, var(--green-700) 100%);
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: 0 8px 32px rgba(22, 163, 74, 0.3);
    color: var(--white);
}

.contact-card .section-header h2 {
    color: var(--white);
}

.contact-card .section-icon {
    background: rgba(255, 255, 255, 0.2);
}

.contact-card .section-icon i {
    color: var(--white);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 0.75rem;
}

.contact-item i {
    width: 24px;
    height: 24px;
    color: var(--white);
    flex-shrink: 0;
}

.contact-label {
    font-size: 0.9rem;
    color: var(--green-100);
    margin-bottom: 0.25rem;
}

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

.contact-item a:hover {
    text-decoration: underline;
}

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

.footer {
    background: linear-gradient(90deg, var(--green-800), var(--green-900));
    color: var(--white);
    padding: 2.5rem 0;
}

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

.footer-brand h3 {
    margin: 0 0 0.25rem 0;
    font-size: 1.25rem;
}

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

.footer-developer {
    text-align: right;
}

.footer p {
    margin: 0.25rem 0;
}

.footer-institution,
.muted {
    color: rgba(255, 255, 255, 0.8);
    opacity: 0.95;
    font-size: 0.95rem;
}

.footer a {
    color: var(--green-100);
    text-decoration: none;
}

.footer a:hover {
    text-decoration: underline;
}

.footer-dev-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.06);
    color: var(--white);
    transition: background 0.2s ease, transform 0.15s ease;
}

.footer-dev-link i {
    width: 22px;
    height: 22px;
    color: var(--white);
}

.footer-dev-link:hover {
    background: rgba(255, 255, 255, 0.12);
    transform: translateY(-2px);
}

@media (min-width: 640px) {
    .container {
        padding: 0 1.5rem;
    }

    .nav-btn span {
        display: inline;
    }

    .profile-image {
        width: 250px;
        height: 250px;
    }

    .professor-name {
        font-size: 2.5rem;
    }

    .courses-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .contact-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-grid {
        grid-template-columns: 1fr 1fr 240px;
        align-items: center;
    }
}

@media (max-width: 1024px) {
    .nav-toggle {
        display: inline-flex;
        align-items: center;
        justify-content: center;
    }

    .nav-toggle {
        display: inline-flex;
        align-items: center;
        justify-content: center;
    }

    /* collapse nav links into a vertical panel controlled by the toggle */
    .nav-links {
        display: none;
        flex-direction: column;
        gap: 0.25rem;
        position: absolute;
        left: 0;
        right: 0;
        top: 64px;
        background: rgba(255, 255, 255, 0.98);
        padding: 1rem;
        border-bottom: 1px solid var(--green-100);
        box-shadow: 0 8px 24px rgba(22, 163, 74, 0.08);
        z-index: 1100;
    }

    .nav-links .nav-btn {
        width: 100%;
        justify-content: flex-start;
        padding: 0.75rem 1rem;
        border-radius: 0.5rem;
    }

    .nav-links.open {
        display: flex;
    }
}

@media (min-width: 768px) {
    .hero {
        padding: 5rem 0;
    }

    .section-card {
        padding: 2.5rem;
    }

    .contact-card {
        padding: 2.5rem;
    }
}

@media (min-width: 1024px) {
    .nav-links {
        gap: 2rem;
    }

    .nav-btn {
        padding: 0.75rem 1.5rem;
        font-size: 1rem;
    }

    .container {
        padding: 0 2rem;
    }
}

/* Print Styles */
@media print {
    .navbar {
        display: none;
    }

    .social-links {
        display: none;
    }

    body {
        background: white;
    }

    .section-card,
    .contact-card {
        box-shadow: none;
        border: 1px solid #ddd;
        page-break-inside: avoid;
    }
}

/* Developer page specific styles (moved from inline) */
.developer-section {
    background: linear-gradient(135deg, #f0f4ff 0%, #ffffff 100%);
    padding: 3rem 1rem;
    margin-top: 2rem;
    border-radius: 1rem;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
}

.developer-card {
    background: #fff;
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
    max-width: 1000px;
    margin: 0 auto;
}

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

.developer-title {
    font-size: 2rem;
    font-weight: 700;
    color: #1e3a8a;
    margin-bottom: 0.25rem;
}

.developer-role {
    font-size: 1.15rem;
    color: #2563eb;
    font-weight: 500;
}

.developer-description {
    font-size: 1.05rem;
    color: #374151;
    margin-bottom: 1rem;
    line-height: 1.7;
}

.developer-skills ul,
.developer-purpose ul,
.developer-contact ul {
    margin: 0.5rem 0 1rem 1.25rem;
    color: #374151;
    font-size: 1rem;
    line-height: 1.7;
}

.developer-skills ul {
    columns: 2;
    column-gap: 2rem;
}

.developer-contact a {
    color: #2563eb;
    text-decoration: none;
    word-break: break-word;
    transition: color 0.2s;
}

.developer-contact a:hover {
    color: #1e3a8a;
}

.developer-social {
    margin-top: 1rem;
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.developer-social a {
    color: #2563eb;
    font-size: 1.35rem;
    transition: color 0.2s;
}

.developer-social a:hover {
    color: #1e3a8a;
}

.dev-back {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.25rem;
    border-radius: 9999px;
    background: #2563eb;
    color: #fff;
    text-decoration: none;
    font-weight: 600;
    transition: background 0.2s;
    box-shadow: 0 2px 8px rgba(30, 58, 138, 0.08);
}

.dev-back i {
    margin-right: 0.25rem;
}

@media (max-width: 768px) {
    .developer-card {
        padding: 1.25rem;
    }

    .developer-header {
        flex-direction: column;
        align-items: center;
        gap: 0.75rem;
    }

    .developer-skills ul {
        columns: 1;
    }
}

@media (max-width: 480px) {
    .developer-title {
        font-size: 1.6rem;
    }

    .developer-role {
        font-size: 1rem;
    }

    .developer-description {
        font-size: 1rem;
    }

    .developer-social {
        flex-wrap: wrap;
        gap: 0.5rem;
    }
}