:root {
    --bg-color: #05050A; /* Deep dark blue/black */
    --surface-color: rgba(255, 255, 255, 0.03);
    --border-color: rgba(255, 255, 255, 0.08);
    --text-primary: #F3F4F6;
    --text-secondary: #9CA3AF;
    --accent-primary: #8B5CF6; /* Vibrant violet */
    --accent-secondary: #3B82F6; /* Bright blue */
    --gradient-text: linear-gradient(135deg, #A78BFA, #60A5FA);
    --font-main: 'Outfit', sans-serif;
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

/* Light Theme Variables */
body.light-theme {
    --bg-color: #F1F5F9; /* Daha zengin açık gri arka plan */
    --surface-color: #FFFFFF; /* Daha net beyaz kartlar */
    --border-color: #CBD5E1; /* Kart sınırlarını daha belirgin yapan çerçeveler */
    --text-primary: #020617; /* Gece siyahı yüksek kontrastlı metin */
    --text-secondary: #334155; /* Koyu gri okunaklı alt metin */
    --accent-primary: #5B21B6; /* Vurgular için daha koyu ve okunaklı mor */
    --gradient-text: linear-gradient(135deg, #6D28D9, #1D4ED8); /* Metin gradyanı için koyu geçişler */
}

/* Particles in light theme should be visible */
body.light-theme #particles-js {
    background-color: var(--bg-color);
}

/* Gündüz teması kart gölgelendirmeleri */
body.light-theme .glass-card {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(15px);
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.1), 0 0 10px rgba(0, 0, 0, 0.03);
    border: 1px solid rgba(0, 0, 0, 0.08); /* Kartların dış hatlarını belirginleştirir */
}

body.light-theme .service-card:hover {
    box-shadow: 0 25px 50px -12px rgba(109, 40, 217, 0.25);
    transform: translateY(-10px);
}

body.light-theme .portfolio-item {
    box-shadow: 0 15px 35px -5px rgba(0, 0, 0, 0.12);
    border: 1px solid rgba(0, 0, 0, 0.06);
}

body.light-theme .navbar.scrolled {
    background: rgba(248, 250, 252, 0.9);
    border-bottom: 1px solid var(--border-color);
}

body.light-theme .mobile-menu-btn span {
    background: var(--text-primary);
}

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

html {
    scroll-behavior: smooth;
    font-family: var(--font-main);
}

body {
    overflow-x: hidden;
    background-color: var(--bg-color);
    color: var(--text-primary);
    transition: background-color 0.4s ease, color 0.4s ease;
}

::selection {
    background: var(--accent-primary);
    color: #fff;
}

/* Typography */
h1, h2, h3, h4 {
    font-weight: 800;
    line-height: 1.2;
}

h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

h2 span, .text-gradient, .about-stats strong {
    background: var(--gradient-text);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text; 
}

p {
    color: var(--text-secondary);
    line-height: 1.6;
    font-size: 1.1rem;
    transition: color 0.4s ease;
}

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

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}

.section-padding {
    padding: 100px 0;
}

.section-heading {
    text-align: center;
    margin-bottom: 60px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 14px 28px;
    border-radius: 50px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    font-family: inherit;
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: #fff;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
}

.btn-primary:hover {
    box-shadow: 0 6px 25px rgba(139, 92, 246, 0.6);
    transform: translateY(-2px);
}

.btn-secondary {
    background: rgba(139, 92, 246, 0.1);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background: rgba(139, 92, 246, 0.2);
    transform: translateY(-2px);
}

.btn-outline {
    border: 1px solid var(--border-color);
    padding: 10px 24px;
    background: transparent;
    color: var(--text-primary);
    border-radius: 50px;
    cursor: pointer;
    transition: var(--transition);
}

.btn-outline:hover {
    border-color: var(--accent-primary);
    background: rgba(139, 92, 246, 0.1);
}

#theme-toggle {
    font-size: 1.3rem;
    padding: 6px 14px;
    margin-left: 10px;
    border-radius: 50px;
}

.w-100 {
    width: 100%;
}

/* Particles Background */
#particles-js {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -2;
    background-color: var(--bg-color);
    transition: background-color 0.4s ease;
}

/* Background Blobs */
.background-blobs {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    overflow: hidden;
    pointer-events: none;
}

.blob {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.5;
    animation: float 20s infinite ease-in-out alternate;
}

.blob-1 {
    top: -10%;
    right: -5%;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, var(--accent-primary), transparent 70%);
}

.blob-2 {
    bottom: -20%;
    left: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, var(--accent-secondary), transparent 70%);
    animation-delay: -5s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(-50px, 50px) scale(1.1); }
}

/* Glassmorphism */
.glass-card {
    background: var(--surface-color);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 2rem;
    transition: var(--transition);
}

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    padding: 20px 0;
    z-index: 1000;
    transition: var(--transition);
}

.navbar.scrolled {
    background: rgba(5, 5, 10, 0.8);
    backdrop-filter: blur(10px);
    padding: 15px 0;
    border-bottom: 1px solid var(--border-color);
}

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

.nav-actions {
    display: flex;
    align-items: center;
    gap: 15px;
}

.logo {
    font-size: 1.8rem;
    font-weight: 800;
    letter-spacing: 1px;
}

.logo span {
    color: var(--accent-primary);
}

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

.nav-links a {
    font-weight: 600;
    font-size: 0.95rem;
    position: relative;
    color: var(--text-primary);
}

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

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

.mobile-menu-btn {
    display: none;
    background: transparent;
    border: none;
    cursor: pointer;
    flex-direction: column;
    gap: 5px;
}

.mobile-menu-btn span {
    width: 25px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

/* Hero */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding-top: 80px;
}

.hero h1 {
    font-size: 4.5rem;
    margin-bottom: 20px;
}

.hero p {
    font-size: 1.3rem;
    max-width: 600px;
    margin: 0 auto 40px;
}

.hero-btns {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

/* Services */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.service-card {
    transition: var(--transition);
}

.service-card:hover {
    transform: translateY(-10px);
    border-color: rgba(139, 92, 246, 0.4);
}

.service-card .icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.service-card h3 {
    margin-bottom: 15px;
    font-size: 1.4rem;
}

/* Portfolio */
.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.portfolio-item {
    border-radius: 20px;
    overflow: hidden;
    position: relative;
    cursor: pointer;
    border: 1px solid var(--border-color);
    aspect-ratio: 4 / 3;
}

.portfolio-img {
    height: 100%;
    width: 100%;
    transition: var(--transition);
    background-size: cover;
    background-position: center;
}

body.light-theme .portfolio-info {
    background: linear-gradient(to top, rgba(255,255,255,1) 30%, rgba(255,255,255,0.85) 70%, transparent);
    color: #020617;
    text-shadow: 0 1px 2px rgba(255,255,255,0.9);
}

.portfolio-info {
    position: absolute;
    bottom: -100px;
    left: 0;
    width: 100%;
    padding: 30px 20px 20px;
    background: linear-gradient(to top, rgba(0,0,0,0.9), transparent);
    transition: var(--transition);
}

.portfolio-info h3 {
    font-size: 1.4rem;
    margin-bottom: 5px;
}

.portfolio-info span {
    color: var(--accent-primary);
    font-size: 0.9rem;
    font-weight: 600;
}

.portfolio-item:hover .portfolio-img {
    transform: scale(1.05);
}

.portfolio-item:hover .portfolio-info {
    bottom: 0;
}

/* About */
.about-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-stats {
    display: flex;
    gap: 30px;
    list-style: none;
    margin-top: 30px;
}

.about-stats li {
    display: flex;
    flex-direction: column;
}

.about-stats span {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.about-image {
    height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(139, 92, 246, 0.1), rgba(59, 130, 246, 0.1));
    border-radius: 20px;
}

/* Contact */
.contact-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.contact-details p {
    margin-bottom: 15px;
    font-size: 1.1rem;
    color: var(--text-primary);
}

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

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 15px;
    border: 1px solid var(--border-color);
    background: rgba(0, 0, 0, 0.2);
    border-radius: 10px;
    color: var(--text-primary);
    font-family: inherit;
    transition: var(--transition);
}

body.light-theme .form-group input,
body.light-theme .form-group select,
body.light-theme .form-group textarea {
    background: rgba(255,255,255,0.8);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
    background: rgba(255, 255, 255, 0.05);
}

body.light-theme .form-group input:focus,
body.light-theme .form-group textarea:focus {
    background: #fff;
}

/* Footer */
footer {
    border-top: 1px solid var(--border-color);
    padding: 30px 0;
    background: rgba(0,0,0,0.5);
    transition: background-color 0.4s ease;
}

body.light-theme footer {
    background: rgba(255, 255, 255, 0.5);
}

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

.footer-logo {
    font-weight: 800;
    font-size: 1.2rem;
}

.footer-logo span {
    color: var(--accent-primary);
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-links a {
    width: 35px;
    height: 35px;
    border-radius: 50%;
    background: var(--surface-color);
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.social-links a:hover {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
    color: #fff;
}

/* Animations */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

.delay-1 { transition-delay: 0.1s; }
.delay-2 { transition-delay: 0.2s; }
.delay-3 { transition-delay: 0.3s; }

/* Responsive */
@media (max-width: 900px) {
    .about-container, .contact-container {
        grid-template-columns: 1fr;
    }
    .hero h1 { font-size: 3rem; }
}

@media (max-width: 768px) {
    .nav-links, .navbar .contact-btn {
        display: none;
    }
    .mobile-menu-btn {
        display: flex;
    }
    .footer-content {
        flex-direction: column;
        gap: 20px;
        text-align: center;
    }
    .nav-actions {
        gap: 8px; /* Closer buttons on mobile */
    }
}

/* Nav Circle Buttons (Theme & Lang) */
.nav-circle-btn {
    width: 40px;
    height: 40px;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    border-radius: 50%;
    margin: 0;
}

/* Language Dropdown */
.lang-dropdown {
    position: relative;
    display: inline-block;
}

.lang-dropdown-content {
    display: none;
    position: absolute;
    right: 0;
    top: 50px;
    min-width: 120px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
    border-radius: 12px;
    overflow: hidden;
    z-index: 1001;
    padding: 0;
}

.lang-dropdown-content a {
    color: var(--text-primary);
    padding: 12px 16px;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 600;
    transition: var(--transition);
}

.lang-dropdown-content a:hover {
    background-color: rgba(139, 92, 246, 0.2);
    color: #fff;
}

/* Hover vs Click */
@media (min-width: 769px) {
    .lang-dropdown:hover .lang-dropdown-content {
        display: block;
    }
}
.lang-dropdown.active .lang-dropdown-content {
    display: block;
}

/* Modal Overlay (First Time Visitor) */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 1;
    transition: opacity 0.5s ease;
}

.lang-modal-box {
    text-align: center;
    max-width: 400px;
    width: 90%;
    padding: 40px;
}

.lang-modal-box h2 {
    color: var(--accent-primary);
    margin-bottom: 10px;
}

.lang-modal-box p {
    margin-bottom: 30px;
    font-size: 1.05rem;
}

.lang-options {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.btn-lang {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 15px;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    transition: var(--transition);
    font-family: inherit;
}

body.light-theme .btn-lang {
    background: rgba(255, 255, 255, 0.8);
    color: #020617;
}

.btn-lang:hover {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(139, 92, 246, 0.4);
}

.btn-lang .flag {
    font-size: 1.5rem;
}