/* ============================================
   ROOT VARIABLES & THEME DEFINITIONS
   ============================================ */

:root {
    /* Light Theme Colors */
    --primary-color: #6366f1;
    --secondary-color: #ec4899;
    --background-color: #ffffff;
    --surface-color: #f8fafc;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --accent-color: #0ea5e9;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;

    /* Transitions */
    --transition-fast: 200ms ease-in-out;
    --transition-normal: 300ms ease-in-out;
    --transition-slow: 500ms ease-in-out;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.15);
}

/* Dark Theme */
body.dark-theme {
    --background-color: #0f172a;
    --surface-color: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --border-color: #334155;
}

/* Ocean Theme */
body.ocean-theme {
    --primary-color: #0369a1;
    --secondary-color: #06b6d4;
    --accent-color: #0284c7;
    --background-color: #ecf0f1;
    --surface-color: #f8fbfc;
    --text-primary: #0c3a4e;
    --text-secondary: #475569;
    --border-color: #cbd5e1;
}

body.ocean-theme.dark-theme {
    --background-color: #0f4a5a;
    --surface-color: #164056;
    --text-primary: #e0f2fe;
    --text-secondary: #94c5d4;
    --border-color: #334155;
}

/* Forest Theme */
body.forest-theme {
    --primary-color: #059669;
    --secondary-color: #10b981;
    --accent-color: #14b8a6;
    --background-color: #f0fdf4;
    --surface-color: #f0fdf4;
    --text-primary: #065f46;
    --text-secondary: #4b5563;
    --border-color: #d1fae5;
}

body.forest-theme.dark-theme {
    --background-color: #1b4332;
    --surface-color: #2d6a4f;
    --text-primary: #e0f2e9;
    --text-secondary: #a8d5ba;
    --border-color: #40916c;
}

/* ============================================
   GLOBAL STYLES
   ============================================ */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-primary);
    transition: background-color var(--transition-normal), color var(--transition-normal);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* ============================================
   NAVIGATION BAR
   ============================================ */

.navbar {
    background-color: var(--surface-color);
    backdrop-filter: blur(10px);
    background-color: rgba(255, 255, 255, 0.8);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: all var(--transition-fast);
}

body.dark-theme .navbar {
    background-color: rgba(15, 23, 42, 0.8);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-md) var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    transition: transform var(--transition-fast);
}

.nav-logo:hover {
    transform: scale(1.05);
}

.nav-logo i {
    font-size: 1.75rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-xl);
    margin: 0;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width var(--transition-fast);
}

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

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

.theme-toggle {
    background: none;
    border: none;
    font-size: 1.25rem;
    color: var(--text-primary);
    cursor: pointer;
    transition: transform var(--transition-fast), color var(--transition-fast);
    margin-left: var(--spacing-lg);
}

.theme-toggle:hover {
    transform: rotate(20deg);
    color: var(--primary-color);
}

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

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    margin: 5px 0;
    transition: all var(--transition-fast);
    border-radius: 2px;
}

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
    min-height: calc(100vh - 70px);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-2xl) var(--spacing-lg);
    gap: var(--spacing-2xl);
}

.hero-content {
    flex: 1;
    max-width: 600px;
    animation: slideInLeft 0.8s ease-out;
}

.hero-title {
    font-size: clamp(2.5rem, 8vw, 4rem);
    font-weight: 800;
    margin-bottom: var(--spacing-md);
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.hero-description {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-lg);
    text-decoration: none;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: inline-block;
    font-size: 1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    box-shadow: var(--shadow-lg);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

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

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    animation: slideInRight 0.8s ease-out;
}

.code-animation {
    width: 100%;
    max-width: 400px;
    aspect-ratio: 1;
    background: linear-gradient(135deg, var(--surface-color), var(--primary-color));
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    box-shadow: var(--shadow-xl);
    border: 1px solid var(--border-color);
}

.code-line {
    height: 12px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    border-radius: var(--radius-sm);
    animation: pulse 2s ease-in-out infinite;
}

.code-line:nth-child(1) {
    width: 100%;
    animation-delay: 0s;
}

.code-line:nth-child(2) {
    width: 90%;
    animation-delay: 0.2s;
}

.code-line:nth-child(3) {
    width: 95%;
    animation-delay: 0.4s;
}

.code-line:nth-child(4) {
    width: 85%;
    animation-delay: 0.6s;
}

/* ============================================
   ABOUT SECTION
   ============================================ */

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    margin-bottom: var(--spacing-2xl);
    text-align: center;
    position: relative;
    padding-bottom: var(--spacing-xl);
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.about {
    padding: var(--spacing-2xl) var(--spacing-lg);
    background-color: var(--surface-color);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-2xl);
    align-items: start;
}

.about-text p {
    margin-bottom: var(--spacing-lg);
    color: var(--text-secondary);
    line-height: 1.8;
    font-size: 1.1rem;
}

.about-text h3 {
    margin: var(--spacing-xl) 0 var(--spacing-lg) 0;
    color: var(--text-primary);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: var(--spacing-md);
}

.skill-tag {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    text-align: center;
    font-weight: 600;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.skill-tag:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.about-stats {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
}

.stat-card {
    background-color: var(--background-color);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    transition: all var(--transition-normal);
    text-align: center;
}

.stat-card:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.stat-card h4 {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

.stat-card p {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
}

/* ============================================
   PROJECTS SECTION
   ============================================ */

.projects {
    padding: var(--spacing-2xl) var(--spacing-lg);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xl);
}

.project-card {
    background-color: var(--surface-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    border: 1px solid var(--border-color);
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

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

.project-card-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.project-card-icon {
    font-size: 2rem;
    color: var(--primary-color);
}

.project-card-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
}

.project-card-description {
    color: var(--text-secondary);
    line-height: 1.6;
}

.project-card-stats {
    display: flex;
    gap: var(--spacing-lg);
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.project-card-stat {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.project-card-footer {
    margin-top: auto;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
    display: flex;
    gap: var(--spacing-md);
}

.project-card-link {
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9rem;
    transition: all var(--transition-fast);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    flex: 1;
    justify-content: center;
}

.project-card-link-primary {
    background-color: var(--primary-color);
    color: white;
}

.project-card-link-primary:hover {
    background-color: var(--secondary-color);
}

.project-skeleton {
    background-color: var(--surface-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    animation: skeleton-loading 1.5s infinite;
}

.skeleton-header {
    width: 100%;
    height: 30px;
    margin-bottom: var(--spacing-lg);
    background: linear-gradient(90deg, var(--border-color) 25%, var(--surface-color) 50%, var(--border-color) 75%);
    background-size: 200% 100%;
    animation: shimmer 2s infinite;
    border-radius: var(--radius-md);
}

.skeleton-text {
    width: 100%;
    height: 20px;
    background: linear-gradient(90deg, var(--border-color) 25%, var(--surface-color) 50%, var(--border-color) 75%);
    background-size: 200% 100%;
    animation: shimmer 2s infinite;
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
}

/* ============================================
   PORTFOLIO SECTION
   ============================================ */

.portfolio {
    padding: var(--spacing-2xl) var(--spacing-lg);
    background-color: var(--surface-color);
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--spacing-xl);
    margin-top: var(--spacing-xl);
}

.portfolio-item {
    background-color: var(--background-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
}

.portfolio-item:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

.portfolio-image {
    width: 100%;
    height: 200px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: white;
}

.portfolio-content {
    padding: var(--spacing-xl);
    display: flex;
    flex-direction: column;
    flex: 1;
    gap: var(--spacing-md);
}

.portfolio-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
}

.portfolio-description {
    color: var(--text-secondary);
    flex: 1;
}

.portfolio-link {
    display: inline-block;
    padding: var(--spacing-md) var(--spacing-lg);
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    text-decoration: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    transition: all var(--transition-fast);
    text-align: center;
    margin-top: var(--spacing-md);
}

.portfolio-link:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* ============================================
   CONTACT SECTION
   ============================================ */

.contact {
    padding: var(--spacing-2xl) var(--spacing-lg);
}

.contact-description {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: var(--spacing-2xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.contact-links {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
    max-width: 1000px;
    margin: 0 auto;
}

.contact-card {
    background-color: var(--surface-color);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    border: 2px solid var(--border-color);
    text-decoration: none;
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    color: inherit;
}

.contact-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    background-color: var(--background-color);
}

.contact-card i {
    font-size: 2.5rem;
    color: var(--primary-color);
}

.contact-card h3 {
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.contact-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
    background-color: var(--surface-color);
    padding: var(--spacing-xl) var(--spacing-lg);
    text-align: center;
    color: var(--text-secondary);
    border-top: 1px solid var(--border-color);
}

.footer p {
    margin: 0;
}

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes pulse {
    0%, 100% {
        opacity: 0.5;
    }
    50% {
        opacity: 1;
    }
}

@keyframes shimmer {
    0% {
        background-position: -1000px 0;
    }
    100% {
        background-position: 1000px 0;
    }
}

@keyframes skeleton-loading {
    0%, 100% {
        opacity: 0.7;
    }
    50% {
        opacity: 1;
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */

@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .nav-menu {
        display: none;
    }

    .hero {
        flex-direction: column;
        padding: var(--spacing-xl) var(--spacing-lg);
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .about-content {
        grid-template-columns: 1fr;
    }

    .skills-grid {
        grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }

    .portfolio-grid {
        grid-template-columns: 1fr;
    }

    .contact-links {
        grid-template-columns: 1fr;
    }

    .contact-card {
        flex-direction: column;
        text-align: center;
    }

    .hero-image {
        margin-top: var(--spacing-xl);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-md);
    }

    .nav-container {
        padding: var(--spacing-md);
    }

    .hero {
        padding: var(--spacing-lg) var(--spacing-md);
    }

    .hero-title {
        font-size: 1.5rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .btn {
        padding: var(--spacing-md) var(--spacing-lg);
        font-size: 0.9rem;
    }

    .hero-buttons {
        gap: var(--spacing-sm);
    }
}

/* ============================================
   UTILITIES
   ============================================ */

.loading {
    display: inline-block;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}