:root {
  --color-bg: #f8fafc;
  --color-bg-alt: #e0f7fa;
  --color-text: #181a1b;
  --color-primary: #0891b2;
  --color-card: #fff;
  --color-nav: #fff;
  --color-shadow: #0891b244;
  --color-accent: #0891b2;
  --color-accent-hover: #0e7490;
  --color-secondary: #64748b;
}
[data-theme="dark"] {
  --color-bg: #10151a;
  --color-bg-alt: #18212b;
  --color-text: #e0e6ed;
  --color-primary: #06b6d4;
  --color-card: #18212b;
  --color-nav: #151d26;
  --color-shadow: #06b6d466;
  --color-accent: #06b6d4;
  --color-accent-hover: #0891b2;
  --color-secondary: #94a3b8;
}
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'JetBrains Mono', monospace;
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Navigation */
.navbar {
    position: fixed;
    width: 100%;
    background: var(--color-nav);
    box-shadow: 0 2px 8px var(--color-shadow);
    z-index: 1000;
    padding: 1rem 0;
    transition: var(--transition);
}

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

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

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

.nav-links a {
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--accent);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--accent);
    transition: var(--transition);
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

.mobile-menu {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-primary);
}

/* Hero Section */
.hero {
    position: relative;
    overflow: hidden;
    min-height: 480px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6rem 2rem 2rem;
    text-align: center;
    background: linear-gradient(135deg, var(--color-bg-alt) 0%, var(--color-bg) 100%);
}

.hero-bg-gradient {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    z-index: 0;
    background: linear-gradient(120deg, #0891b2 0%, #e0f7fa 100%);
    opacity: 0.12;
    pointer-events: none;
}

.hero-bg-wave {
    position: absolute;
    left: 0; right: 0; bottom: 0;
    z-index: 1;
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    width: 100%;
}

.hero-content h1 {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    margin-bottom: 1rem;
    background: linear-gradient(45deg, var(--accent), #64ffda);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 0.8s ease forwards;
}

.hero-content h2 {
    font-size: clamp(1.5rem, 3vw, 2rem);
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.2s;
}

.hero-location {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.3s;
}

.hero-location i {
    margin-right: 0.5rem;
    color: var(--accent);
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.4s;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 1rem;
    background: rgba(100, 255, 218, 0.05);
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.stat-item:hover {
    transform: translateY(-5px);
    background: rgba(100, 255, 218, 0.1);
}

.stat-number {
    font-size: clamp(1.8rem, 4vw, 2.5rem);
    font-weight: 700;
    color: var(--accent);
    line-height: 1;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 1px;
    text-align: center;
}

.hero-description {
    max-width: 600px;
    margin: 2rem auto;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.5s;
    font-size: 1.1rem;
    line-height: 1.6;
    color: var(--text-primary);
}

.tech-stack {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
    margin: 2rem 0;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.6s;
}

.tech-badge {
    padding: 0.5rem 1rem;
    background: rgba(100, 255, 218, 0.1);
    border: 1px solid rgba(100, 255, 218, 0.3);
    border-radius: 20px;
    color: var(--accent);
    font-size: 0.9rem;
    transition: var(--transition);
}

.tech-badge:hover {
    background: rgba(100, 255, 218, 0.2);
    transform: translateY(-2px);
}

.social-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 2rem;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 0.8s;
}

.social-button {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: rgba(100, 255, 218, 0.1);
    border: 1px solid rgba(100, 255, 218, 0.3);
    border-radius: var(--border-radius);
    color: var(--accent);
    text-decoration: none;
    transition: var(--transition);
}

.social-buttons a {
  transition: box-shadow 0.2s, transform 0.2s, background 0.2s;
}
.social-buttons a:hover {
  box-shadow: 0 4px 16px #0891b244;
  transform: translateY(-4px) scale(1.07) rotate(-2deg);
  background: #06b6d4 !important;
}

/* Sections */
.section {
    padding: 4rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.section h2 {
    font-size: clamp(2rem, 4vw, 2.5rem);
    margin-bottom: 3rem;
    text-align: center;
    position: relative;
}

.section h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: var(--color-accent);
    border-radius: 2px;
}

/* About Section */
.about-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem;
    background: rgba(255, 255, 255, 0.02);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

.about-content:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateY(-5px);
}

.about-content p {
    margin-bottom: 1rem;
    line-height: 1.8;
    color: var(--text-primary);
}

.about-content a {
    color: var(--accent);
    text-decoration: none;
    position: relative;
    transition: var(--transition);
}

.about-content a:hover {
    color: var(--accent-hover);
}

/* Experience Section */
.experience-container {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.experience-card {
    background: var(--color-card);
    color: var(--color-text);
    box-shadow: 0 2px 8px var(--color-shadow);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.1);
    padding: 2rem 2.5rem;
    transition: var(--transition);
    position: relative;
}

.experience-card:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateY(-5px) scale(1.01);
    box-shadow: 0 4px 24px 0 rgba(8,145,178,0.10);
}

.exp-header {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    margin-bottom: 1rem;
}

.exp-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--accent);
}

.exp-company {
    display: flex;
    align-items: center;
    gap: 0.5em;
}

.exp-company a {
    color: var(--text-primary);
    text-decoration: underline dotted;
    text-underline-offset: 2px;
    font-weight: 500;
    transition: color 0.2s;
}

.exp-company a:hover {
    color: var(--accent-hover);
    text-decoration: underline;
}

.exp-location {
    color: var(--text-secondary);
    font-size: 0.95em;
    margin-left: 0.5em;
}

.exp-dates {
    font-size: 0.95em;
    color: var(--text-secondary);
}

.exp-details {
    margin-left: 1.2em;
    color: var(--text-secondary);
    font-size: 1.05em;
    line-height: 1.7;
    padding-top: 0.5em;
    padding-bottom: 0.5em;
}

.exp-details li {
    margin-bottom: 0.5em;
}

/* External link icon for experience company */
.exp-link-icon {
    color: var(--accent);
    margin-right: 0.35em;
    font-size: 1em;
    vertical-align: middle;
    opacity: 0.85;
    transition: color 0.2s;
}

@media (max-width: 768px) {
    .experience-card {
        padding: 1.2rem 1rem;
    }
    .experience-container {
        gap: 1.2rem;
    }
    .exp-title {
        font-size: 1.05rem;
    }
    .exp-details {
        font-size: 0.98em;
        margin-left: 0.5em;
    }
}

@media (max-width: 480px) {
    .experience-card {
        padding: 1rem 0.5rem;
    }
    .exp-header {
        gap: 0.15rem;
    }
    .exp-title {
        font-size: 1em;
    }
    .exp-details {
        font-size: 0.93em;
        margin-left: 0.2em;
    }
}

/* Experience Timeline */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--accent);
    transform: translateX(-50%);
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
    display: flex;
    align-items: center;
}

.timeline-year {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    background: var(--accent);
    color: var(--bg-primary);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    font-weight: bold;
    z-index: 2;
}

.timeline-content {
    width: 45%;
    padding: 1.5rem;
    background: rgba(255, 255, 255, 0.02);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

.timeline-item:nth-child(odd) .timeline-content {
    margin-left: auto;
}

.timeline-content:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateY(-3px);
}

.timeline-content h3 {
    color: var(--accent);
    margin-bottom: 0.5rem;
    font-size: 1.2rem;
}

.timeline-content h4 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.timeline-content .location,
.timeline-content .date {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 0.25rem;
}

.timeline-content i {
    margin-right: 0.5rem;
    color: var(--accent);
}

/* Projects Section */
.repos-container {
    max-width: 1000px;
    margin: 0 auto;
    position: relative;
}

.repos-container.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
    padding-left: 0;
    padding-right: 0;
}

.repos-container.timeline::before {
    content: '';
    position: absolute;
    left: 32px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--accent);
    z-index: 0;
}

.repo-timeline-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: rgba(255, 255, 255, 0.02);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
    position: relative;
}

.repo-timeline-item:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateY(-3px);
}

.repo-year {
    background: var(--accent);
    color: var(--bg-primary);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    font-weight: bold;
    margin-right: 1.5rem;
    flex-shrink: 0;
}

.repo-content {
    flex: 1;
}

.repo-content h3 {
    color: var(--accent);
    margin-bottom: 0.5rem;
    font-size: 1.2rem;
}

.repo-content p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

.repo-stats {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.repo-stats span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.repo-stats i {
    color: var(--accent);
}

.repo-links {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.repo-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: rgba(100, 255, 218, 0.1);
    border: 1px solid rgba(100, 255, 218, 0.3);
    border-radius: var(--border-radius);
    color: var(--accent);
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

.repo-link:hover {
    background: rgba(100, 255, 218, 0.2);
    transform: translateY(-2px);
}

.repo-topics {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.topic {
    padding: 0.25rem 0.75rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 15px;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.repo-timeline-item.timeline {
    position: relative;
    display: flex;
    align-items: flex-start;
    margin-bottom: 2.5rem;
    padding-left: 90px;
    background: rgba(255, 255, 255, 0.02);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
    z-index: 1;
    min-height: 70px;
}

.repo-timeline-item.timeline::before {
    content: '';
    position: absolute;
    left: 32px;
    top: 32px;
    bottom: -2.5rem;
    width: 2px;
    background: var(--accent);
    z-index: 0;
}

.repo-timeline-item.timeline:last-child::before {
    display: none;
}

.repo-year.timeline {
    position: absolute;
    left: 20px;
    top: 24px;
    transform: none;
    background: var(--accent);
    color: var(--bg-primary);
    padding: 0.5rem 1rem;
    border-radius: 50%;
    font-weight: bold;
    z-index: 2;
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 0 0 4px rgba(8,145,178,0.15);
    font-size: 0.95rem;
    border: 2px solid var(--bg-primary);
}

.repo-content {
    flex: 1;
    min-height: 48px;
    margin-top: 8px;
}

/* Contact Section */
.contact-content {
    max-width: 600px;
    margin: 0 auto;
    padding: 2rem;
    background: rgba(255, 255, 255, 0.02);
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

.contact-content:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateY(-5px);
}

.contact-content p {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    transition: var(--transition);
}

.contact-content p:hover {
    color: var(--accent);
}

.contact-content i {
    color: var(--accent);
    font-size: 1.2rem;
    width: 20px;
}

.contact-content a {
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
}

.contact-content a:hover {
    color: var(--accent);
}

.contact-social {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-top: 2rem;
}

.contact-social a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background: rgba(100, 255, 218, 0.1);
    border: 1px solid rgba(100, 255, 218, 0.3);
    border-radius: 50%;
    color: var(--accent);
    font-size: 1.2rem;
    transition: var(--transition);
}

.contact-social a:hover {
    background: rgba(100, 255, 218, 0.2);
    transform: translateY(-3px);
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* Animations */
@keyframes fadeIn {
  to { opacity: 1; }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    .nav-content {
        padding: 0 1rem;
    }

    .mobile-menu {
        display: block;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--bg-primary);
        padding: 1rem;
        flex-direction: column;
        align-items: center;
        gap: 1rem;
        border-top: 1px solid rgba(255, 255, 255, 0.1);
    }

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

    .nav-links a {
        margin: 0;
        padding: 0.5rem 1rem;
    }

    .hero {
        padding: 5rem 1rem 2rem;
    }

    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: 1rem;
    }

    .stat-item {
        padding: 0.75rem;
    }

    .tech-stack {
        gap: 0.5rem;
    }

    .tech-badge {
        padding: 0.4rem 0.8rem;
        font-size: 0.8rem;
    }

    .social-buttons {
        flex-direction: column;
        align-items: center;
    }

    .social-button {
        width: 100%;
        max-width: 200px;
        justify-content: center;
    }

    .section {
        padding: 3rem 1rem;
    }

    .about-content,
    .contact-content {
        padding: 1.5rem;
    }

    .timeline::before {
        left: 20px;
    }

    .timeline-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .timeline-year {
        position: relative;
        left: 0;
        transform: none;
        margin-bottom: 1rem;
    }

    .timeline-content {
        width: 100%;
        margin-left: 0 !important;
    }

    .repo-timeline-item {
        flex-direction: column;
        gap: 1rem;
    }

    .repo-year {
        margin-right: 0;
        align-self: flex-start;
    }

    .repo-stats {
        gap: 0.75rem;
    }

    .repo-links {
        gap: 0.75rem;
    }

    .contact-content p {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
        text-align: center;
    }

    .contact-social {
        gap: 1rem;
    }

    .repos-container.timeline::before {
        left: 16px;
    }
    .repo-timeline-item.timeline {
        padding-left: 60px;
    }
    .repo-year.timeline {
        left: 0;
        width: 36px;
        height: 36px;
        font-size: 0.75rem;
        top: 18px;
    }
    .repo-content {
        margin-top: 0;
    }
}

@media (max-width: 480px) {
    .hero-stats {
        grid-template-columns: 1fr;
    }

    .tech-stack {
        justify-content: flex-start;
    }

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

    .repo-link {
        justify-content: center;
    }
    
    .filter-buttons {
        gap: 0.4rem;
    }
    
    .filter-btn {
        padding: 0.4rem 0.8rem;
        font-size: 0.8rem;
    }
    
    .filter-count {
        font-size: 0.75em;
    }
}

/* Filter Container */
.filter-container {
    margin-bottom: 2rem;
    text-align: center;
}

.filter-buttons {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.filter-btn {
    padding: 0.5rem 1rem;
    background: rgba(100, 255, 218, 0.1);
    border: 1px solid rgba(100, 255, 218, 0.3);
    border-radius: var(--border-radius);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
    font-size: 0.9rem;
}

.filter-btn:hover,
.filter-btn.active {
    background: var(--accent);
    border-color: var(--accent);
    color: var(--bg-primary);
    transform: translateY(-2px);
}

.filter-btn[aria-selected="true"] {
    background: var(--accent);
    border-color: var(--accent);
    color: var(--bg-primary);
}

.filter-count {
    font-size: 0.8em;
    opacity: 0.8;
    margin-left: 0.25rem;
}

.filter-btn:hover .filter-count,
.filter-btn.active .filter-count {
    opacity: 1;
}

.filter-buttons {
    gap: 0.5rem;
}

/* Modern gradient arka plan ve wave */
.hero {
  position: relative;
  overflow: hidden;
  min-height: 480px;
  background: linear-gradient(135deg, #e0f7fa 0%, #b2ebf2 100%);
}
.hero-bg-gradient {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  z-index: 0;
  background: linear-gradient(120deg, #0891b2 0%, #e0f7fa 100%);
  opacity: 0.12;
  pointer-events: none;
}
.hero-bg-wave {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  z-index: 1;
  pointer-events: none;
}
.hero-content {
  position: relative;
  z-index: 2;
}

/* SVG logo stil */
.logo-svg svg {
  display: block;
  transition: transform 0.3s cubic-bezier(.4,2,.6,1);
}
.logo-svg:hover svg {
  transform: scale(1.12) rotate(-6deg);
  filter: drop-shadow(0 2px 8px #0891b2aa);
}

/* Fade-in animasyonları */
.animated-fadein {
  opacity: 0;
  animation: fadeIn 1.2s ease 0.1s forwards;
}
.animated-fadein-delay {
  opacity: 0;
  animation: fadeIn 1.2s ease 0.7s forwards;
}

/* Parlayan başlık efekti */
.shine {
  background: linear-gradient(90deg, #0891b2 20%, #fff 50%, #0891b2 80%);
  background-size: 200% auto;
  color: #0891b2;
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  animation: shine-move 2.5s linear infinite;
}
@keyframes shine-move {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.repo-media {
  margin: 0.5rem 0 1rem 0;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 120px;
  background: rgba(8,145,178,0.03);
  border-radius: 8px;
  overflow: hidden;
}
.repo-media img, .repo-media video {
  max-width: 100%;
  max-height: 180px;
  border-radius: 8px;
  box-shadow: 0 2px 8px #0891b233;
  object-fit: cover;
}

/* Tema toggle ikonları için kontrast ayarı */
.theme-toggle .theme-icon-light { color: #fbbf24; }
.theme-toggle .theme-icon-dark { color: #06b6d4; }
[data-theme="dark"] .theme-toggle .theme-icon-light { color: #fbbf24; }
[data-theme="dark"] .theme-toggle .theme-icon-dark { color: #06b6d4; }

/* Tema butonu stilleri */
.theme-toggle {
  background: var(--color-card);
  border: 1.5px solid var(--color-accent);
  border-radius: 50%;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-left: 1rem;
  cursor: pointer;
  box-shadow: 0 2px 8px var(--color-shadow);
  transition: background 0.2s, border 0.2s, box-shadow 0.2s;
  position: relative;
}
.theme-toggle:hover {
  background: var(--color-accent);
  border-color: var(--color-accent-hover);
}
.theme-toggle .theme-icon {
  display: block;
  color: var(--color-accent);
  transition: opacity 0.2s;
}
.theme-toggle .theme-icon-dark {
  display: none;
}
[data-theme="dark"] .theme-toggle .theme-icon {
  display: none;
}
[data-theme="dark"] .theme-toggle .theme-icon-dark {
  display: block;
  color: var(--color-accent);
}

/* Hero section koyu tema için özel gradient */
.hero {
  background: linear-gradient(135deg, var(--color-bg-alt) 0%, var(--color-bg) 100%);
}
[data-theme="dark"] .hero {
  background: linear-gradient(135deg, #0a192f 0%, #10151a 100%);
}

/* Kartlar için border görünürlüğü artırıldı */
.repo-card {
  border: 1.5px solid #b0b6be; /* açık temada daha koyu ve belirgin gri */
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  margin-bottom: 2rem;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.repo-card:hover {
  border-color: #0891b2;
  box-shadow: 0 4px 16px #0891b244;
}
[data-theme="dark"] .repo-card {
  border: 1.5px solid #334155;
  background: #1e293b;
  box-shadow: 0 2px 8px rgba(8,145,178,0.08);
}
[data-theme="dark"] .repo-card:hover {
  border-color: #06b6d4;
  box-shadow: 0 4px 16px #06b6d444;
}

/* Açık temada .repo-timeline-item için arka planı beyaz, border'ı koyu gri (#b0b6be), hover'da ise açık maviye yakın bir arka plan ve accent border olacak şekilde güncellendi. Koyu temada mevcut kontrast korundu. */
.repo-timeline-item {
  background: #fff;
  border: 1.5px solid #b0b6be;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  margin-bottom: 2rem;
  transition: border-color 0.2s, box-shadow 0.2s, background 0.2s;
}
.repo-timeline-item:hover {
  border-color: #0891b2;
  box-shadow: 0 4px 16px #0891b244;
  background: #f0fafd;
}
[data-theme="dark"] .repo-timeline-item {
  background: #1e293b;
  border: 1.5px solid #334155;
  box-shadow: 0 2px 8px rgba(8,145,178,0.08);
}
[data-theme="dark"] .repo-timeline-item:hover {
  border-color: #06b6d4;
  box-shadow: 0 4px 16px #06b6d444;
  background: #16202a;
}