/* Theme: Modern — Source Sans/Serif, değişkenler, koyu üst çubuk */
@import url("https://fonts.googleapis.com/css2?family=Source+Sans+3:ital,wght@0,400;0,600;0,700;1,400&family=Source+Serif+4:ital,opsz,wght@0,8..60,600;0,8..60,700;1,8..60,400&display=swap");

:root {
    --brand: #0a2342;
    --brand-light: #123a6b;
    --accent: #0d9488;
    --accent-hover: #0f766e;
    --bg-page: #f1f5f9;
    --surface: #ffffff;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.05);
    --shadow: 0 4px 6px -1px rgba(15, 23, 42, 0.07), 0 2px 4px -2px rgba(15, 23, 42, 0.05);
    --shadow-md: 0 10px 25px -5px rgba(15, 23, 42, 0.08);
    --radius: 12px;
    --radius-sm: 8px;
    --font-sans: "Source Sans 3", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    --font-serif: "Source Serif 4", Georgia, "Times New Roman", serif;
    --container: 1120px;
    --nav-h: 64px;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: var(--font-sans);
    font-size: 1.05rem;
    line-height: 1.65;
    color: var(--text);
    background: var(--bg-page);
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 1.25rem;
}

/* ---- Navigation ---- */
.navbar {
    background: linear-gradient(180deg, var(--brand) 0%, #071a30 100%);
    color: #fff;
    padding: 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow-md);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    min-height: var(--nav-h);
}

.brand {
    font-family: var(--font-serif);
    font-size: 1.2rem;
    font-weight: 700;
    color: #fff;
    text-decoration: none;
    letter-spacing: -0.02em;
}

.brand:hover {
    color: #e2e8f0;
}

.nav-links {
    display: flex;
    gap: 0.15rem;
    list-style: none;
    margin: 0;
    padding: 0;
    align-items: center;
}

.nav-links a {
    color: rgba(255, 255, 255, 0.88);
    text-decoration: none;
    font-size: 0.92rem;
    font-weight: 500;
    padding: 0.45rem 0.65rem;
    border-radius: 6px;
    transition: background 0.2s ease, color 0.2s ease;
}

.nav-links a:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.1);
}

.hamburger {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: #fff;
    padding: 0.35rem 0.5rem;
    border-radius: 6px;
    line-height: 1;
}

.hamburger:hover {
    background: rgba(255, 255, 255, 0.1);
}

.hamburger i {
    font-size: 1.25rem;
    color: inherit;
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        padding: 0.75rem 1rem 1rem;
        background: linear-gradient(180deg, var(--brand) 0%, #071a30 100%);
        box-shadow: var(--shadow-md);
        gap: 0.25rem;
        align-items: stretch;
    }

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

    .nav-links a {
        padding: 0.65rem 0.75rem;
    }

    .hamburger {
        display: block;
    }
}

/* ---- Hero (home) ---- */
.hero {
    background: linear-gradient(165deg, #f8fafc 0%, #e2e8f0 48%, #f1f5f9 100%);
    padding: 3.5rem 0 4rem;
    text-align: center;
    border-bottom: 1px solid var(--border);
}

.hero h1 {
    font-family: var(--font-serif);
    font-size: clamp(1.85rem, 4vw, 2.5rem);
    font-weight: 700;
    margin: 0 0 0.75rem;
    color: var(--brand);
    letter-spacing: -0.03em;
}

.hero .container > p {
    margin: 0.35rem 0;
    color: var(--text-muted);
    font-size: 1.05rem;
}

.hero .container > p:first-of-type {
    color: var(--text);
    font-weight: 600;
    font-size: 1.1rem;
}

.profile-photo {
    text-align: center;
    margin-bottom: 1.5rem;
}

.profile-photo img {
    width: 188px;
    height: 188px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid #fff;
    box-shadow:
        0 0 0 1px var(--border),
        0 12px 40px -8px rgba(15, 23, 42, 0.25);
}

/* ---- Journal logos strip ---- */
.journal-logos {
    text-align: center;
    padding: 2.25rem 0;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
}

.journal-logos .logos {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    flex-wrap: wrap;
}

.journal-logos .logos a {
    display: block;
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.journal-logos .logos a:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

.journal-logos .logos img {
    max-width: 220px;
    height: auto;
    vertical-align: middle;
}

/* ---- Highlights ---- */
.highlights {
    padding: 3rem 0 3.5rem;
}

.highlights .container {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 1.25rem;
}

.highlight-card {
    background: var(--surface);
    padding: 1.75rem 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    text-align: center;
    flex: 1;
    min-width: 200px;
    max-width: 280px;
    position: relative;
    overflow: hidden;
}

.highlight-card::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--brand), var(--accent));
}

.highlight-card h3 {
    font-family: var(--font-serif);
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--brand);
    margin: 0 0 0.35rem;
    letter-spacing: -0.03em;
}

.highlight-card p {
    margin: 0;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

/* ---- Page sections: shared title ---- */
.publications h1,
.conferences h1,
.projects h1,
.journals h1,
.research-interests h1,
.contact h1,
.cv-section h1,
.photos .gallery-title {
    font-family: var(--font-serif);
    font-size: clamp(1.65rem, 3vw, 2rem);
    font-weight: 700;
    color: var(--brand);
    margin: 0 0 1.5rem;
    letter-spacing: -0.02em;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--border);
}

/* ---- Publications ---- */
.publications,
.conferences {
    padding: 3rem 0 4rem;
}

.publication-list,
.conference-list {
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
}

.publication-item,
.conference-item {
    background: var(--surface);
    padding: 1.25rem 1.35rem;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    border-left: 4px solid var(--brand);
    box-shadow: var(--shadow-sm);
    font-size: 1rem;
    line-height: 1.65;
    margin-bottom: 0;
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    transition: box-shadow 0.2s ease;
}

.publication-item:hover,
.conference-item:hover {
    box-shadow: var(--shadow);
}

.pub-number,
.conf-number {
    color: var(--brand);
    font-weight: 700;
    font-size: 1.05rem;
    min-width: 2.25rem;
    flex-shrink: 0;
}

.pub-content,
.conf-content {
    flex: 1;
    font-size: 0.98rem;
    color: var(--text);
}

.pub-content strong,
.conf-content strong {
    font-weight: 600;
    color: var(--brand);
}

.pub-content em,
.conf-content em {
    font-style: italic;
    color: var(--text-muted);
}

/* ---- Footer ---- */
footer {
    background: linear-gradient(180deg, var(--brand) 0%, #051018 100%);
    color: rgba(255, 255, 255, 0.85);
    padding: 2rem 0;
    text-align: center;
    margin-top: 0;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

footer p {
    margin: 0.35rem 0;
    font-size: 0.9rem;
}

footer p:last-child {
    font-size: 0.8rem;
    opacity: 0.65;
}

/* ---- Research ---- */
.research-interests {
    padding: 3rem 0 4rem;
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.25rem;
    margin-top: 1rem;
}

.research-card {
    background: var(--surface);
    padding: 1.75rem;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    border-left: 4px solid var(--accent);
    box-shadow: var(--shadow-sm);
}

.research-card h2,
.research-card h3 {
    font-family: var(--font-serif);
    color: var(--brand);
    margin-top: 0;
}

/* ---- CV ---- */
.cv-section {
    padding: 3rem 1.25rem 4rem;
    text-align: center;
}

.cv-info {
    max-width: 640px;
    margin: 0 auto;
    text-align: left;
}

.cv-table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
    background: var(--surface);
    border-radius: var(--radius-sm);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border);
}

.cv-table td {
    padding: 0.85rem 1rem;
    border-bottom: 1px solid var(--border);
}

.cv-table tr:last-child td {
    border-bottom: none;
}

.cv-list {
    list-style: none;
    padding: 0;
    margin: 1.5rem 0 0;
}

.cv-list li {
    padding: 0.85rem 1rem;
    border-left: 4px solid var(--accent);
    margin-bottom: 0.65rem;
    background: var(--surface);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border);
    border-left-width: 4px;
}

.cv-download-container {
    text-align: center;
    margin-top: 2rem;
}

.cv-download-btn {
    display: inline-block;
    padding: 0.85rem 1.75rem;
    background: var(--brand);
    color: #fff;
    text-decoration: none;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: 1rem;
    transition: background 0.2s ease, transform 0.15s ease;
    box-shadow: var(--shadow);
}

.cv-download-btn:hover {
    background: var(--brand-light);
    transform: translateY(-1px);
}

/* ---- Journals ---- */
.journals {
    padding: 3rem 0 4rem;
    text-align: center;
}

.journals-list {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.journal-card {
    background: var(--surface);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    overflow: hidden;
    width: 220px;
    text-align: center;
    transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.journal-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-md);
}

.journal-cover {
    width: 100%;
    height: auto;
    display: block;
}

.journal-info {
    padding: 1.25rem 1rem 1.5rem;
}

.journal-title {
    font-family: var(--font-serif);
    font-size: 1.05rem;
    color: var(--brand);
    font-weight: 700;
    margin: 0 0 0.5rem;
    line-height: 1.35;
}

.journal-info p {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.journal-link {
    display: inline-block;
    margin-top: 0.75rem;
    padding: 0.55rem 1.15rem;
    background: var(--brand);
    color: #fff;
    text-decoration: none;
    border-radius: var(--radius-sm);
    font-size: 0.88rem;
    font-weight: 600;
    transition: background 0.2s ease;
}

.journal-link:hover {
    background: var(--accent);
    color: #fff;
}

@media (max-width: 768px) {
    .journals-list {
        flex-direction: column;
        align-items: center;
    }

    .journal-card {
        width: 100%;
        max-width: 300px;
    }
}

/* ---- Projects ---- */
.projects {
    padding: 3rem 0 4rem;
}

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

.project-card {
    display: flex;
    align-items: flex-start;
    padding: 1.35rem 1.4rem;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    background: var(--surface);
    box-shadow: var(--shadow-sm);
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.project-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.project-number {
    font-family: var(--font-serif);
    font-size: 1.35rem;
    font-weight: 700;
    color: var(--brand);
    margin-right: 1rem;
    min-width: 2rem;
}

.project-info h3 {
    font-size: 1.15rem;
    margin: 0 0 0.5rem;
    font-weight: 700;
    color: var(--brand);
    font-family: var(--font-serif);
}

.project-info .author {
    font-size: 0.95rem;
    color: var(--text-muted);
    font-weight: 600;
    margin-bottom: 0.65rem;
}

.badge {
    display: inline-block;
    padding: 0.35rem 0.75rem;
    border-radius: 999px;
    font-size: 0.78rem;
    font-weight: 600;
    color: #fff;
    margin-right: 0.4rem;
    margin-bottom: 0.35rem;
}

.badge.type {
    background: #1d4ed8;
}

.badge.status {
    background: #059669;
}

.badge.date {
    background: #d97706;
}

.amount {
    display: block;
    margin-top: 0.5rem;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text);
}

@media (max-width: 768px) {
    .project-card {
        flex-direction: column;
        align-items: flex-start;
    }
}

/* ---- Contact ---- */
.contact {
    padding: 3rem 0 4rem;
    text-align: center;
}

.contact-info,
.contact-form {
    flex: 1;
    background: var(--surface);
    padding: 1.75rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
}

.contact-info h2,
.contact-form h2 {
    font-family: var(--font-serif);
    font-size: 1.35rem;
    margin: 0 0 1rem;
    color: var(--brand);
}

.contact-info p {
    font-size: 0.95rem;
    color: var(--text);
    margin-bottom: 0.65rem;
    text-align: left;
}

.contact-info p i {
    color: var(--accent);
    margin-right: 0.5rem;
    width: 1.1rem;
}

.contact-info a {
    color: var(--brand-light);
    text-decoration: none;
    font-weight: 600;
}

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

.contact-info .social-icons {
    margin-top: 1.25rem;
}

.contact-info .social-icons a {
    display: inline-block;
    font-size: 1.4rem;
    color: var(--brand);
    margin-right: 0.85rem;
    transition: color 0.2s ease, transform 0.15s ease;
}

.contact-info .social-icons a:hover {
    color: var(--accent);
    transform: scale(1.08);
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 0.75rem 0.9rem;
    margin-bottom: 0.85rem;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: var(--brand);
    box-shadow: 0 0 0 3px rgba(10, 35, 66, 0.12);
}

.contact-form button {
    width: 100%;
    padding: 0.85rem;
    background: var(--brand);
    color: #fff;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 1.05rem;
    font-weight: 600;
    cursor: pointer;
    font-family: inherit;
    transition: background 0.2s ease;
}

.contact-form button:hover {
    background: var(--brand-light);
}

.contact-map {
    margin-top: 2.5rem;
    text-align: center;
}

.contact-map h2 {
    font-family: var(--font-serif);
    font-size: 1.35rem;
    margin-bottom: 1rem;
    color: var(--brand);
}

.contact-content {
    display: flex;
    align-items: stretch;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
    min-height: auto;
}

.contact-info,
.contact-form {
    max-width: 440px;
    width: 100%;
}

.contact-form .success-message {
    background: #059669;
    color: #fff;
    padding: 0.85rem;
    text-align: center;
    border-radius: var(--radius-sm);
    display: none;
    margin-bottom: 1rem;
    font-weight: 600;
}

@media (max-width: 768px) {
    .contact-content {
        flex-direction: column;
        align-items: center;
    }

    .publication-item,
    .conference-item {
        font-size: 0.92rem;
        flex-direction: column;
    }
}

/* ---- Photos gallery ---- */
.photos {
    padding: 3rem 0 4rem;
}

.gallery-title {
    text-align: center;
    margin: 0 0 2rem;
    color: var(--brand);
    font-family: var(--font-serif);
    font-size: clamp(1.65rem, 3vw, 2rem);
    font-weight: 700;
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    max-width: var(--container);
    margin: 0 auto;
}

.photo-card {
    background: var(--surface);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.photo-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.photo img {
    width: 100%;
    height: 250px;
    object-fit: cover;
    object-position: center center;
    border-bottom: 1px solid var(--border);
}

.caption {
    padding: 1rem 1.1rem 1.15rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.92rem;
    line-height: 1.5;
}

.photo.vertical img {
    object-position: top center;
}

@media (max-width: 768px) {
    .gallery-grid {
        gap: 1rem;
    }

    .gallery-title {
        font-size: 1.65rem;
    }
}

/* ---- Lightbox ---- */
.lightbox {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(15, 23, 42, 0.92);
    z-index: 2000;
    cursor: zoom-out;
    backdrop-filter: blur(4px);
}

.lightbox.active {
    display: flex;
    justify-content: center;
    align-items: center;
}

.lightbox img {
    max-width: 90%;
    max-height: 90%;
    border: 3px solid #fff;
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-md);
}

.close-btn {
    position: absolute;
    top: 1.25rem;
    right: 1.25rem;
    color: #fff;
    font-size: 2rem;
    cursor: pointer;
    background: rgba(0, 0, 0, 0.35);
    border: none;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    line-height: 1;
    transition: background 0.2s ease;
}

.close-btn:hover {
    background: rgba(0, 0, 0, 0.55);
}

/* ---- Focus visibility (keyboard) ---- */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }

    html {
        scroll-behavior: auto;
    }
}