/* ==========================================
   CSS Custom Properties (Variables)
   ========================================== */
:root {
    --color-primary: #0a0a0a;
    --color-secondary: #1a1a1a;
    --color-accent: #3b82f6;
    --color-accent-hover: #2563eb;
    --color-text: #ffffff;
    --color-text-muted: #a3a3a3;
    --color-border: #262626;
    --color-card-bg: #141414;
    
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 5rem;
    
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;
    
    --border-radius-sm: 0.375rem;
    --border-radius-md: 0.5rem;
    --border-radius-lg: 1rem;
    --border-radius-full: 9999px;
    
    --max-width: 1200px;
    --navbar-height: 80px;
}

/* ==========================================
   Reset & Base Styles
   ========================================== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-family);
    background-color: var(--color-primary);
    color: var(--color-text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

ul {
    list-style: none;
}

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

/* ==========================================
   Navigation
   ========================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background-color: rgba(10, 10, 10, 0.9);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--color-text);
}

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

.nav-links {
    display: flex;
    gap: var(--spacing-lg);
}

.nav-links a {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-muted);
    transition: color var(--transition-fast);
}

.nav-links a:hover {
    color: var(--color-text);
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.hamburger span {
    width: 24px;
    height: 2px;
    background-color: var(--color-text);
    transition: all var(--transition-normal);
}

/* ==========================================
   Hero Section
   ========================================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-2xl) var(--spacing-lg);
    position: relative;
    overflow: hidden;
}

.hero-content {
    max-width: 800px;
    text-align: center;
    z-index: 1;
}

.hero-greeting {
    font-size: 1.125rem;
    color: var(--color-accent);
    font-weight: 500;
    margin-bottom: var(--spacing-sm);
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.hero-name {
    font-size: clamp(2.5rem, 8vw, 5rem);
    font-weight: 700;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: var(--spacing-sm);
}

.hero-title {
    font-size: clamp(1.25rem, 4vw, 2rem);
    font-weight: 400;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-md);
}

.hero-description {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    max-width: 600px;
    margin: 0 auto var(--spacing-xl);
    line-height: 1.7;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-sm);
    justify-content: center;
    flex-wrap: wrap;
}

.hero-visual {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 600px;
    height: 600px;
    pointer-events: none;
}

.hero-shape {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.1) 0%, transparent 70%);
    animation: pulse 8s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
        opacity: 0.5;
    }
    50% {
        transform: scale(1.1);
        opacity: 0.8;
    }
}

/* ==========================================
   Buttons
   ========================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.875rem 2rem;
    font-size: 0.9375rem;
    font-weight: 500;
    border-radius: var(--border-radius-full);
    transition: all var(--transition-normal);
    cursor: pointer;
    border: none;
}

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

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

.btn-secondary {
    background-color: transparent;
    color: var(--color-text);
    border: 1px solid var(--color-border);
}

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

/* ==========================================
   Section Styles
   ========================================== */
section {
    padding: var(--spacing-2xl) var(--spacing-lg);
}

.section-container {
    max-width: var(--max-width);
    margin: 0 auto;
}

.section-title {
    font-size: clamp(2rem, 5vw, 2.5rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: var(--spacing-xl);
    text-align: center;
}

.subsection-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-accent);
    margin-bottom: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.subsection-title:first-of-type {
    margin-top: 0;
}

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

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

.about-text p {
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-md);
    font-size: 1.0625rem;
    line-height: 1.8;
}

.about-text p:last-child {
    margin-bottom: 0;
}

.about-highlights {
    display: grid;
    gap: var(--spacing-md);
}

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

.highlight-card:hover {
    border-color: var(--color-accent);
    transform: translateY(-4px);
}

.highlight-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-accent);
    margin-bottom: var(--spacing-xs);
}

.highlight-label {
    font-size: 0.875rem;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

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

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

.timeline-item {
    position: relative;
    padding-left: var(--spacing-xl);
    padding-bottom: var(--spacing-xl);
}

.timeline-item:last-child {
    padding-bottom: 0;
}

.timeline-marker {
    position: absolute;
    left: -6px;
    top: 0;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background-color: var(--color-accent);
    border: 3px solid var(--color-primary);
}

.timeline-content {
    background-color: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-lg);
    transition: all var(--transition-normal);
}

.timeline-content:hover {
    border-color: var(--color-accent);
}

.timeline-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.timeline-company {
    font-size: 1rem;
    color: var(--color-accent);
    margin-bottom: var(--spacing-xs);
}

.timeline-period {
    font-size: 0.875rem;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-sm);
}

.timeline-description {
    color: var(--color-text-muted);
    line-height: 1.7;
}

/* ==========================================
   Skills Section
   ========================================== */
.skills {
    background-color: var(--color-secondary);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.skill-category {
    background-color: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-lg);
    transition: all var(--transition-normal);
}

.skill-category:hover {
    border-color: var(--color-accent);
}

.skill-category-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--color-text);
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

.skill-tag {
    display: inline-block;
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    background-color: var(--color-secondary);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-full);
    color: var(--color-text-muted);
    transition: all var(--transition-fast);
}

.skill-tag:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

/* ==========================================
   Contact Section
   ========================================== */
.contact-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.contact-intro {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-xl);
    line-height: 1.7;
}

.contact-links {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.contact-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 1rem 1.5rem;
    background-color: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-full);
    color: var(--color-text);
    font-weight: 500;
    transition: all var(--transition-normal);
}

.contact-link:hover {
    background-color: var(--color-accent);
    border-color: var(--color-accent);
    color: var(--color-text);
    transform: translateY(-2px);
}

.contact-icon {
    width: 20px;
    height: 20px;
}

/* ==========================================
   Footer
   ========================================== */
.footer {
    border-top: 1px solid var(--color-border);
    padding: var(--spacing-lg);
    text-align: center;
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
}

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

.footer-location {
    margin-top: var(--spacing-xs);
}

/* ==========================================
   Responsive Design
   ========================================== */
@media (max-width: 968px) {
    .about-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-xl);
    }
    
    .about-highlights {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--color-primary);
        border-bottom: 1px solid var(--color-border);
        flex-direction: column;
        padding: var(--spacing-md);
        gap: var(--spacing-md);
    }
    
    .nav-links.active {
        display: flex;
    }
    
    .nav-links a {
        padding: var(--spacing-sm) 0;
    }
    
    .hamburger {
        display: flex;
    }
    
    .hamburger.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }
    
    .hamburger.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }
    
    .hero {
        padding-top: var(--navbar-height);
    }
    
    .about-highlights {
        grid-template-columns: 1fr;
    }
    
    .timeline::before {
        left: 7px;
    }
    
    .timeline-marker {
        left: 0;
    }
    
    .timeline-item {
        padding-left: var(--spacing-xl);
    }
    
    .contact-links {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    :root {
        --spacing-lg: 1.5rem;
        --spacing-xl: 2rem;
        --spacing-2xl: 3rem;
    }
    
    .hero-cta {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 280px;
    }
}

/* ==========================================
   Animations
   ========================================== */
/* Default styles - elements are visible by default */
.hero-content,
.timeline-item,
.skill-category {
    opacity: 1;
    transform: none;
}

/* Only apply animations for users who haven't requested reduced motion */
@media (prefers-reduced-motion: no-preference) {
    .hero-content {
        animation: fadeInUp 0.8s ease-out;
    }
    
    .timeline-item {
        animation: fadeInLeft 0.6s ease-out;
        animation-fill-mode: both;
    }
    
    .timeline-item:nth-child(1) { animation-delay: 0.1s; }
    .timeline-item:nth-child(2) { animation-delay: 0.2s; }
    .timeline-item:nth-child(3) { animation-delay: 0.3s; }
    
    .skill-category {
        animation: fadeInUp 0.5s ease-out;
        animation-fill-mode: both;
    }
    
    .skill-category:nth-child(1) { animation-delay: 0.1s; }
    .skill-category:nth-child(2) { animation-delay: 0.2s; }
    .skill-category:nth-child(3) { animation-delay: 0.3s; }
    .skill-category:nth-child(4) { animation-delay: 0.4s; }
}

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

@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}