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

.skip-to-content {
    position: absolute;
    top: -40px;
    left: 0;
    background: #000;
    color: #fff;
    padding: 8px 16px;
    text-decoration: none;
    z-index: 10000;
    border-radius: 0 0 8px 0;
}

.skip-to-content:focus {
    top: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    background-image: 
        radial-gradient(circle at 25% 25%, var(--pattern-color) 1px, transparent 1px),
        radial-gradient(circle at 75% 75%, var(--pattern-color) 1px, transparent 1px),
        linear-gradient(45deg, transparent 40%, var(--pattern-color) 50%, transparent 60%);
    background-size: 40px 40px, 40px 40px, 80px 80px;
    background-position: 0 0, 20px 20px, 0 0;
    overflow-x: hidden;
    transition: background-color 0.3s ease, color 0.3s ease;
}

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

.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: var(--navbar-bg);
    background-image: 
        linear-gradient(90deg, transparent 0%, var(--pattern-color) 50%, transparent 100%);
    background-size: 200px 100%;
    animation: navbarShimmer 8s ease-in-out infinite;
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: all 0.3s ease;
}

@keyframes navbarShimmer {
    0%, 100% { background-position: -200px 0; }
    50% { background-position: calc(100% + 200px) 0; }
}

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

.nav-logo .logo-text {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-color);
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 40px;
}

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

.nav-link:hover {
    opacity: 0.7;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--text-color);
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.theme-toggle {
    display: flex;
    align-items: center;
    margin-right: 20px;
}

.theme-toggle-btn {
    background: none;
    border: 2px solid var(--text-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 16px;
    color: var(--text-color);
}

.theme-toggle-btn:hover {
    background: var(--text-color);
    color: var(--bg-color);
    transform: scale(1.1);
}

.bar {
    width: 25px;
    height: 3px;
    background: var(--text-color);
    margin: 3px 0;
    transition: 0.3s;
}

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 100px 0 50px;
    background: linear-gradient(135deg, var(--bg-color) 0%, var(--secondary-bg) 100%);
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.2;
}

.python-keyword {
    font-family: 'Courier New', monospace;
    color: #0969da;
    font-weight: 700;
}

.python-string {
    font-family: 'Courier New', monospace;
    color: #22863a;
    font-weight: 500;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: #666;
    margin-bottom: 40px;
    font-weight: 400;
}

.hero-buttons {
    display: flex;
    gap: 20px;
}

.btn {
    padding: 15px 30px;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-block;
}

.btn-primary {
    background: #000;
    color: #fff;
}

.btn-primary:hover {
    background: #333;
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: #000;
    border: 2px solid #000;
}

.btn-secondary:hover {
    background: #000;
    color: #fff;
    transform: translateY(-2px);
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.profile-circle {
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background: linear-gradient(135deg, #000 0%, #333 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 80px;
    color: #fff;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-20px); }
}

section {
    padding: 100px 0;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 60px;
    position: relative;
}

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

.about {
    background: var(--secondary-bg);
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-description {
    font-size: 1.1rem;
    color: #666;
    margin-bottom: 30px;
    line-height: 1.8;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    margin-top: 60px;
}

.stat {
    text-align: center;
}

.stat h3 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #000;
    margin-bottom: 10px;
}

.stat p {
    color: #666;
    font-weight: 500;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 60px;
}

.skill-card {
    background: var(--card-bg);
    padding: 40px 30px;
    border-radius: 12px;
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
    cursor: pointer;
}

.skill-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px var(--shadow-color);
}

.skill-icon {
    font-size: 3rem;
    color: var(--text-color);
    margin-bottom: 20px;
}

.skill-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: var(--text-color);
}

.skill-card p {
    opacity: 0.7;
    margin-bottom: 25px;
    line-height: 1.6;
}

.skill-level {
    width: 100%;
    height: 8px;
    background: var(--border-color);
    border-radius: 4px;
    overflow: hidden;
}

.skill-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--text-color) 0%, var(--text-color) 100%);
    border-radius: 4px;
    width: 0;
    transition: width 2s ease;
}

.skill-card.animate .skill-bar[data-level="90"] { width: 90%; }
.skill-card.animate .skill-bar[data-level="85"] { width: 85%; }
.skill-card.animate .skill-bar[data-level="80"] { width: 80%; }
.skill-card.animate .skill-bar[data-level="88"] { width: 88%; }
.skill-card.animate .skill-bar[data-level="75"] { width: 75%; }
.skill-card.animate .skill-bar[data-level="70"] { width: 70%; }

.projects {
    background: var(--secondary-bg);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
    margin-top: 60px;
}

.project-card {
    background: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px var(--shadow-color);
}

.project-image {
    height: 200px;
    background: linear-gradient(135deg, var(--text-color) 0%, var(--text-color) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: var(--bg-color);
    overflow: hidden;
    position: relative;
}

.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
}

.loading-spinner {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-color);
    grid-column: 1 / -1;
}

.loading-spinner i {
    font-size: 3rem;
    margin-bottom: 20px;
    opacity: 0.5;
}

.loading-spinner p {
    font-size: 1.1rem;
    opacity: 0.7;
}

.project-content {
    padding: 30px;
}

.project-content h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: var(--text-color);
}

.project-content p {
    opacity: 0.7;
    margin-bottom: 20px;
    line-height: 1.6;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.tag {
    background: var(--text-color);
    color: var(--bg-color);
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}

.contact-info h3 {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: #000;
}

.contact-info p {
    color: #666;
    margin-bottom: 40px;
    line-height: 1.8;
}

.contact-methods {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.contact-method {
    display: flex;
    align-items: center;
    gap: 15px;
    color: #666;
    text-decoration: none;
    transition: all 0.3s ease;
    padding: 10px;
    border-radius: 8px;
}

.contact-method:hover {
    background: var(--secondary-bg);
    color: var(--text-color);
    transform: translateX(5px);
}

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

.contact-form {
    background: #f8f9fa;
    padding: 40px;
    border-radius: 12px;
}

.form-group {
    margin-bottom: 25px;
}

.form-label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-color);
    font-size: 14px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 15px;
    border: 1px solid #e5e5e5;
    border-radius: 8px;
    font-size: 16px;
    font-family: inherit;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #000;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.footer {
    background: #000;
    color: #fff;
    padding: 40px 0;
    text-align: center;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.social-links {
    display: flex;
    gap: 20px;
}

.social-link {
    color: #fff;
    font-size: 1.5rem;
    transition: color 0.3s ease;
}

.social-link:hover {
    color: #ccc;
}

.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: var(--text-color);
    color: var(--bg-color);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    box-shadow: 0 4px 12px var(--shadow-color);
    transition: all 0.3s ease;
    opacity: 0;
    visibility: hidden;
    z-index: 999;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 20px var(--shadow-color);
}

@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    .theme-toggle {
        margin-right: 10px;
    }
    
    .theme-toggle-btn {
        width: 35px;
        height: 35px;
        font-size: 14px;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--bg-color);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px var(--shadow-color);
        padding: 20px 0;
        border: 1px solid var(--border-color);
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-menu li {
        margin: 15px 0;
    }
    
    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }
    
    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }
    
    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .profile-circle {
        width: 200px;
        height: 200px;
        font-size: 60px;
    }
    
    .about-stats {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 20px;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 200px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .skill-card,
    .contact-form {
        padding: 25px 20px;
    }
    
    .profile-circle {
        width: 150px;
        height: 150px;
        font-size: 40px;
    }
}

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

.fade-in-up {
    animation: fadeInUp 0.6s ease forwards;
}

.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.animate-on-scroll.animated {
    opacity: 1;
    transform: translateY(0);
}

:root {
    --bg-color: #fff;
    --text-color: #000;
    --secondary-bg: #f8f9fa;
    --border-color: #e5e5e5;
    --card-bg: #fff;
    --navbar-bg: rgba(255, 255, 255, 0.95);
    --shadow-color: rgba(0, 0, 0, 0.1);
    --pattern-color: rgba(0, 0, 0, 0.02);
    --accent-color: #007acc;
}

[data-theme="dark"] {
    --bg-color: #0d1117;
    --text-color: #f0f6fc;
    --secondary-bg: #161b22;
    --border-color: #30363d;
    --card-bg: #21262d;
    --navbar-bg: rgba(13, 17, 23, 0.95);
    --shadow-color: rgba(0, 0, 0, 0.3);
    --pattern-color: rgba(255, 255, 255, 0.03);
    --accent-color: #79c0ff;
}


.hero {
    background: 
        linear-gradient(135deg, var(--bg-color) 0%, var(--secondary-bg) 100%),
        radial-gradient(circle at 20% 80%, rgba(0, 122, 204, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(0, 122, 204, 0.10) 0%, transparent 50%);
    background-size: 100% 100%, 600px 600px, 400px 400px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        repeating-linear-gradient(
            45deg,
            transparent,
            transparent 2px,
            var(--pattern-color) 2px,
            var(--pattern-color) 4px
        );
    opacity: 0.3;
    pointer-events: none;
}

.about {
    background: var(--secondary-bg);
    background-image: 
        repeating-conic-gradient(from 0deg at 50% 50%, transparent 0deg, var(--pattern-color) 2deg, transparent 4deg),
        radial-gradient(circle at 30% 70%, var(--pattern-color) 1px, transparent 1px);
    background-size: 60px 60px, 30px 30px;
    position: relative;
}

.skills {
    background: var(--bg-color);
    background-image: 
        linear-gradient(90deg, var(--pattern-color) 1px, transparent 1px),
        linear-gradient(var(--pattern-color) 1px, transparent 1px);
    background-size: 20px 20px;
    position: relative;
}

.projects {
    background: var(--secondary-bg);
    background-image: 
        radial-gradient(circle at 25% 25%, var(--pattern-color) 2px, transparent 2px),
        radial-gradient(circle at 75% 75%, var(--pattern-color) 1px, transparent 1px);
    background-size: 50px 50px, 25px 25px;
    background-position: 0 0, 25px 25px;
}

.skill-card, .project-card, .contact-form {
    background: var(--card-bg);
    background-image: 
        linear-gradient(45deg, transparent 25%, var(--pattern-color) 25%, var(--pattern-color) 50%, transparent 50%, transparent 75%, var(--pattern-color) 75%);
    background-size: 8px 8px;
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.skill-card::before, .project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: left 0.5s ease;
}

.skill-card:hover::before, .project-card:hover::before {
    left: 100%;
}

.skill-card:hover, .project-card:hover {
    box-shadow: 0 20px 40px var(--shadow-color);
    transform: translateY(-5px);
    transition: all 0.3s ease;
}

.section-title::after {
    background: var(--text-color);
}

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

.btn-primary:hover {
    background: var(--text-color);
    opacity: 0.8;
}

.btn-secondary {
    border-color: var(--text-color);
    color: var(--text-color);
}

.btn-secondary:hover {
    background: var(--text-color);
    color: var(--bg-color);
}

.tag {
    background: var(--text-color);
    color: var(--bg-color);
}

.form-group input, .form-group textarea {
    background: var(--card-bg);
    border-color: var(--border-color);
    color: var(--text-color);
}

.form-group input:focus, .form-group textarea:focus {
    border-color: var(--text-color);
}

.footer {
    background: var(--text-color);
    color: var(--bg-color);
}

.social-link {
    color: var(--bg-color);
}

.social-link:hover {
    opacity: 0.7;
}

[data-theme="dark"] .profile-circle {
    background: linear-gradient(135deg, #f0f6fc 0%, #c9d1d9 100%);
    color: #0d1117;
}

[data-theme="dark"] .python-keyword {
    color: #79c0ff;
}

[data-theme="dark"] .python-string {
    color: #a5d6ff;
}

/* Dark Mode spezielle Effekte */
[data-theme="dark"] .hero {
    background: 
        linear-gradient(135deg, var(--bg-color) 0%, var(--secondary-bg) 100%),
        radial-gradient(circle at 20% 80%, rgba(121, 192, 255, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(121, 192, 255, 0.10) 0%, transparent 50%);
}

[data-theme="dark"] .skill-card::before, 
[data-theme="dark"] .project-card::before {
    background: linear-gradient(90deg, transparent, rgba(121, 192, 255, 0.1), transparent);
}

/* Floating particles effect für Dark Mode */
[data-theme="dark"] body::after {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(2px 2px at 20px 30px, rgba(121, 192, 255, 0.3), transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(121, 192, 255, 0.2), transparent),
        radial-gradient(1px 1px at 90px 40px, rgba(121, 192, 255, 0.4), transparent),
        radial-gradient(1px 1px at 130px 80px, rgba(121, 192, 255, 0.3), transparent);
    background-repeat: repeat;
    background-size: 200px 100px;
    animation: floatingParticles 20s linear infinite;
    pointer-events: none;
    z-index: -1;
}

@keyframes floatingParticles {
    0% { transform: translateY(0px) translateX(0px); }
    33% { transform: translateY(-100px) translateX(100px); }
    66% { transform: translateY(-200px) translateX(-100px); }
    100% { transform: translateY(-300px) translateX(0px); }
}