/* ===================================
   CSS Variables & Theme
   =================================== */
:root {
    /* Light Theme Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    --text-primary: #1a1a1a;
    --text-secondary: #4a5568;
    --text-tertiary: #718096;
    --accent-primary: #3b82f6;
    --accent-secondary: #06b6d4;
    --accent-hover: #2563eb;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);

    /* Spacing */
    --container-max-width: 1200px;
    --section-padding: 5rem 1.5rem;

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-base: 16px;

    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 250ms ease-in-out;
    --transition-slow: 350ms ease-in-out;
}

.dark-theme {
    --bg-primary: #0a0a0a;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #2d2d2d;
    --text-primary: #f8f9fa;
    --text-secondary: #cbd5e0;
    --text-tertiary: #a0aec0;
    --accent-primary: #3b82f6;
    --accent-secondary: #06b6d4;
    --accent-tertiary: #8b5cf6;
    --accent-hover: #60a5fa;
    --border-color: #2d3748;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
    --glow-primary: 0 0 20px rgba(59, 130, 246, 0.3);
    --glow-secondary: 0 0 30px rgba(6, 182, 212, 0.2);
}

/* ===================================
   Base Styles
   =================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: var(--font-size-base);
}

body {
    font-family: var(--font-family);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    transition: background-color var(--transition-base), color var(--transition-base);
}

.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: var(--section-padding);
}

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

img {
    max-width: 100%;
    height: auto;
}

/* ===================================
   Navigation
   =================================== */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background-color: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    transition: all var(--transition-base);
}

.nav.scrolled {
    background-color: rgba(10, 10, 10, 0.95);
    box-shadow: var(--shadow-md);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.5rem;
    max-width: var(--container-max-width);
    margin: 0 auto;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--accent-primary);
    transition: color var(--transition-fast);
}

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

.nav-list {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    position: relative;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
    color: var(--accent-primary);
}

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

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

.nav-controls {
    display: flex;
    align-items: center;
    gap: 1rem;
}

/* Language Switcher */
.language-switcher {
    display: flex;
    gap: 0.5rem;
    background-color: var(--bg-secondary);
    padding: 0.25rem;
    border-radius: 0.5rem;
}

.lang-btn {
    padding: 0.35rem 0.75rem;
    font-size: 0.875rem;
    font-weight: 600;
    background: transparent;
    border: none;
    border-radius: 0.375rem;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.lang-btn.active {
    background-color: var(--accent-primary);
    color: white;
}

/* Theme Toggle */
.theme-toggle {
    position: relative;
    width: 40px;
    height: 40px;
    border: none;
    background-color: var(--bg-secondary);
    border-radius: 0.5rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.theme-toggle:hover {
    background-color: var(--bg-tertiary);
    transform: rotate(15deg);
}

.sun-icon,
.moon-icon {
    position: absolute;
    transition: all var(--transition-base);
}

.dark-theme .sun-icon {
    opacity: 0;
    transform: rotate(90deg);
}

.dark-theme .moon-icon {
    opacity: 1;
    transform: rotate(0deg);
}

body:not(.dark-theme) .sun-icon {
    opacity: 1;
    transform: rotate(0deg);
}

body:not(.dark-theme) .moon-icon {
    opacity: 0;
    transform: rotate(-90deg);
}

/* Mobile Toggle */
.mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 0.35rem;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-toggle span {
    width: 24px;
    height: 2px;
    background-color: var(--text-primary);
    transition: all var(--transition-base);
}

/* ===================================
   Hero Section
   =================================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    padding: 8rem 1.5rem 4rem;
    background: radial-gradient(ellipse at top, rgba(59, 130, 246, 0.15) 0%, transparent 50%),
                radial-gradient(ellipse at bottom, rgba(6, 182, 212, 0.1) 0%, transparent 50%),
                var(--bg-primary);
    overflow: hidden;
}

/* Hero Background Elements */
.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    filter: blur(60px);
    animation: float 20s ease-in-out infinite;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(6, 182, 212, 0.08) 0%, transparent 70%);
    border-radius: 50%;
    filter: blur(60px);
    animation: float 15s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(30px, -30px) scale(1.1); }
    66% { transform: translate(-20px, 20px) scale(0.9); }
}

.hero-content {
    text-align: center;
    max-width: 900px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

/* Glassmorphism Profile Container */
.hero-profile {
    margin-bottom: 2rem;
    display: flex;
    justify-content: center;
}

.hero-avatar {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    box-shadow: var(--glow-primary), var(--shadow-xl);
    border: 4px solid rgba(255, 255, 255, 0.1);
    animation: pulse-glow 3s ease-in-out infinite;
}

@keyframes pulse-glow {
    0%, 100% { box-shadow: var(--glow-primary), var(--shadow-xl); }
    50% { box-shadow: var(--glow-secondary), var(--shadow-lg); }
}

.hero-greeting {
    font-size: 1.1rem;
    color: var(--accent-primary);
    font-weight: 600;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.1;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}

.hero-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 2.5rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 3rem;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 3rem;
    flex-wrap: wrap;
    margin-top: 3rem;
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--accent-primary);
    line-height: 1;
    margin-bottom: 0.5rem;
}

.stat-label {
    display: block;
    font-size: 0.875rem;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    color: var(--text-tertiary);
    font-size: 0.875rem;
}

.scroll-arrow {
    width: 24px;
    height: 24px;
    margin: 0.5rem auto 0;
    border-left: 2px solid var(--accent-primary);
    border-bottom: 2px solid var(--accent-primary);
    transform: rotate(-45deg);
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateY(0) rotate(-45deg);
    }
    40% {
        transform: translateY(-10px) rotate(-45deg);
    }
    60% {
        transform: translateY(-5px) rotate(-45deg);
    }
}

/* ===================================
   Buttons
   =================================== */
.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all var(--transition-base);
    border: 2px solid transparent;
    text-align: center;
}

.btn-primary {
    background-color: var(--accent-primary);
    color: white;
}

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background-color: transparent;
    color: var(--accent-primary);
    border-color: var(--accent-primary);
}

.btn-secondary:hover {
    background-color: var(--accent-primary);
    color: white;
    transform: translateY(-2px);
}

.btn-outline {
    background-color: transparent;
    color: var(--text-primary);
    border-color: var(--border-color);
}

.btn-outline:hover {
    background-color: var(--bg-secondary);
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

/* ===================================
   Section Titles
   =================================== */
.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    text-align: center;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.section-subtitle {
    font-size: 1.125rem;
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* ===================================
   About Section
   =================================== */
.about {
    background-color: var(--bg-secondary);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    margin-top: 3rem;
}

.about-text p {
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

.about-cta {
    margin-top: 2rem;
}

.about-skills h3 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

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

.skill-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem;
    background-color: var(--bg-primary);
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
    transition: all var(--transition-base);
}

.skill-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent-primary);
}

.skill-icon {
    font-size: 1.5rem;
}

.skill-name {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-primary);
}

/* ===================================
   Services Section
   =================================== */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 3rem;
}

.service-card {
    padding: 2rem;
    background: rgba(26, 26, 26, 0.6);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-radius: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.05) 0%, rgba(6, 182, 212, 0.05) 100%);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.service-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--glow-primary), var(--shadow-xl);
    border-color: var(--accent-primary);
}

.service-card:hover::before {
    opacity: 1;
}

.service-icon {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    display: block;
}

.service-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.service-description {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

.service-features {
    list-style: none;
}

.service-features li {
    padding: 0.5rem 0;
    color: var(--text-secondary);
    position: relative;
    padding-left: 1.5rem;
}

.service-features li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--accent-primary);
    font-weight: bold;
}

/* ===================================
   Tech Stack Section
   =================================== */
.tech-stack {
    background-color: var(--bg-secondary);
}

.tech-categories {
    display: grid;
    gap: 3rem;
    margin-top: 3rem;
}

.tech-category h3 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--accent-primary);
}

.tech-items {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

.tech-badge {
    padding: 0.75rem 1.5rem;
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 2rem;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-primary);
    transition: all var(--transition-base);
}

.tech-badge:hover {
    background-color: var(--accent-primary);
    color: white;
    border-color: var(--accent-primary);
    transform: translateY(-2px);
}

/* ===================================
   Experience Section
   =================================== */
.timeline {
    position: relative;
    max-width: 900px;
    margin: 3rem auto;
    padding-left: 2rem;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 2px;
    background-color: var(--border-color);
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
    padding-left: 2rem;
}

.timeline-marker {
    position: absolute;
    left: -2rem;
    top: 0;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background-color: var(--accent-primary);
    border: 3px solid var(--bg-primary);
    box-shadow: 0 0 0 3px var(--accent-primary);
}

.timeline-date {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background-color: var(--accent-primary);
    color: white;
    border-radius: 1rem;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.timeline-content h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.timeline-content h4 {
    font-size: 1.125rem;
    color: var(--accent-primary);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.timeline-content p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.achievement {
    margin-top: 1.5rem;
    padding: 1rem;
    background-color: var(--bg-secondary);
    border-left: 3px solid var(--accent-primary);
    border-radius: 0.5rem;
}

.achievement strong {
    display: block;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.achievement p {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ===================================
   Projects Section
   =================================== */
.projects {
    background-color: var(--bg-secondary);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 3rem;
}

.project-card {
    background: rgba(26, 26, 26, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-radius: 1rem;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all var(--transition-base);
    position: relative;
}

.project-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--glow-primary), var(--shadow-xl);
    border-color: var(--accent-primary);
}

.project-image {
    height: 250px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.2), rgba(6, 182, 212, 0.2)),
                url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><rect fill="%231a1a1a" width="100" height="100"/></svg>');
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.project-card:hover .project-image img {
    transform: scale(1.05);
}

.project-placeholder {
    font-size: 4rem;
    position: relative;
    z-index: 1;
}

.project-link {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 40px;
    height: 40px;
    background: rgba(59, 130, 246, 0.9);
    backdrop-filter: blur(5px);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.2rem;
    opacity: 0;
    transition: all var(--transition-base);
    z-index: 2;
}

.project-card:hover .project-link {
    opacity: 1;
}

.project-content {
    padding: 1.5rem;
}

.project-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.project-description {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    padding: 0.375rem 0.875rem;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    font-size: 0.875rem;
    color: var(--accent-primary);
}

/* ===================================
   Contact Section
   =================================== */
.contact-content {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 4rem;
    margin-top: 3rem;
    max-width: 1000px;
    margin-left: auto;
    margin-right: auto;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 2rem;
}

.contact-icon {
    font-size: 2rem;
    flex-shrink: 0;
}

.contact-item h3 {
    font-size: 1rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.contact-item a,
.contact-item p {
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

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

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input,
.form-group textarea {
    padding: 0.875rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    font-family: var(--font-family);
    font-size: 1rem;
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-status {
    padding: 1rem;
    border-radius: 0.5rem;
    text-align: center;
    font-weight: 500;
    display: none;
}

.form-status.success {
    display: block;
    background-color: #d1fae5;
    color: #065f46;
}

.form-status.error {
    display: block;
    background-color: #fee2e2;
    color: #991b1b;
}

/* ===================================
   Footer
   =================================== */
.footer {
    padding: 2rem 1.5rem;
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.footer p {
    color: var(--text-secondary);
    margin: 0.5rem 0;
}

.footer-tagline {
    font-size: 0.875rem;
    color: var(--text-tertiary);
}