/* CSS Custom Properties for Theming - Apple-inspired */
:root {
    /* Colors - Apple-inspired palette */
    --primary-color: #0071e3;
    --secondary-color: #86868b;
    --accent-color: #06c;
    --text-primary: #1d1d1f;
    --text-secondary: #6e6e73;
    --text-light: #86868b;
    --background-primary: #ffffff;
    --background-secondary: #fbfbfd;
    --background-accent: #f5f5f7;
    --border-color: #d2d2d7;
    
    /* Typography - Apple-inspired */
    --font-family-primary: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'SF Pro Text', 'Helvetica Neue', sans-serif;
    --font-family-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, monospace;
    
    /* Font Sizes - Apple scale */
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1.0625rem;
    --font-size-lg: 1.1875rem;
    --font-size-xl: 1.5rem;
    --font-size-2xl: 2rem;
    --font-size-3xl: 2.5rem;
    --font-size-4xl: 3.5rem;
    --font-size-5xl: 4.5rem;
    
    /* Spacing - Apple-inspired generous spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;
    --spacing-4xl: 8rem;
    
    /* Layout */
    --container-max-width: 980px;
    --container-wide: 1400px;
    --border-radius: 18px;
    --border-radius-lg: 24px;
    
    /* Transitions - Apple smooth */
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.6, 1);
    --transition-normal: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Shadows - Subtle Apple-style */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
}

/* Reset and 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-primary);
    font-size: var(--font-size-base);
    line-height: 1.47059;
    letter-spacing: -0.022em;
    color: var(--text-primary);
    background-color: var(--background-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Typography - Apple style */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.0834933333;
    letter-spacing: -0.003em;
    margin-bottom: var(--spacing-md);
}

h1 {
    font-size: var(--font-size-5xl);
    font-weight: 700;
    letter-spacing: -0.015em;
}

h2 {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    letter-spacing: -0.01em;
}

h3 {
    font-size: var(--font-size-3xl);
    font-weight: 600;
}

h4 {
    font-size: var(--font-size-2xl);
    font-weight: 600;
}

h5 {
    font-size: var(--font-size-xl);
    font-weight: 600;
}

h6 {
    font-size: var(--font-size-lg);
    font-weight: 600;
}

p {
    margin-bottom: var(--spacing-md);
    color: var(--text-secondary);
    line-height: 1.47059;
}

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

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

a:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 4px;
    border-radius: 4px;
}

/* Layout Utilities */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

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

.section-title {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    color: var(--text-primary);
    font-size: var(--font-size-4xl);
    font-weight: 700;
}

/* Header Styles - Apple-inspired */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: rgba(255, 255, 255, 0.8);
    backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    z-index: 1000;
    transition: background-color var(--transition-fast);
}

.navigation {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-sm) var(--spacing-lg);
    max-width: var(--container-wide);
    margin: 0 auto;
    height: 44px;
}

.nav-brand .nav-logo {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
    letter-spacing: -0.01em;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-xl);
    align-items: center;
}

.nav-link {
    font-size: var(--font-size-sm);
    font-weight: 400;
    color: var(--text-primary);
    transition: color var(--transition-fast);
    opacity: 0.8;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
    opacity: 1;
    text-decoration: none;
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    flex-direction: column;
    gap: 5px;
    padding: var(--spacing-xs);
}

.hamburger-line {
    width: 18px;
    height: 1px;
    background-color: var(--text-primary);
    transition: all var(--transition-fast);
}

/* Main Content */
.main-content {
    margin-top: 44px;
}

/* Hero Section - Apple-inspired */
.hero {
    padding: var(--spacing-4xl) 0;
    background: linear-gradient(180deg, var(--background-secondary) 0%, var(--background-primary) 100%);
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
    max-width: var(--container-wide);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.hero-text {
    max-width: 600px;
    text-align: left;
}

.hero-title {
    font-size: var(--font-size-5xl);
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    font-weight: 700;
    letter-spacing: -0.015em;
    line-height: 1.05;
}

.hero-description {
    font-size: var(--font-size-xl);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.381;
    letter-spacing: -0.01em;
}

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

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

.profile-image {
    width: 280px;
    height: 280px;
    border-radius: 50%;
    object-fit: cover;
    box-shadow: var(--shadow-lg);
    border: 4px solid var(--background-primary);
}

/* Section Styles */
section {
    padding: var(--spacing-4xl) 0;
}

.about {
    background-color: var(--background-primary);
}

.projects {
    background-color: var(--background-accent);
}

.contact {
    background-color: var(--background-primary);
}

/* About Section - Apple-inspired */
.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-summary {
    font-size: var(--font-size-2xl);
    line-height: 1.381;
    text-align: center;
    margin-bottom: var(--spacing-3xl);
    color: var(--text-primary);
    font-weight: 600;
    letter-spacing: -0.01em;
}

.skills, .achievements {
    margin-bottom: var(--spacing-3xl);
}

.skills-title, .achievements-title {
    color: var(--text-primary);
    font-size: var(--font-size-2xl);
    margin-bottom: var(--spacing-xl);
    text-align: center;
    font-weight: 700;
    letter-spacing: -0.01em;
}

.skills-list, .achievements-list {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.skill-item, .achievement-item {
    padding: var(--spacing-lg);
    background-color: var(--background-primary);
    border-radius: var(--border-radius);
    color: var(--text-secondary);
    font-size: var(--font-size-base);
    line-height: 1.47059;
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-sm);
}

.skill-item:hover, .achievement-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* Projects Section - Apple-inspired carousel */
.projects-grid {
    display: flex;
    gap: var(--spacing-lg);
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    scroll-behavior: smooth;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    padding: var(--spacing-md) 0 var(--spacing-xl);
    margin: 0 calc(-1 * var(--spacing-lg));
    padding-left: var(--spacing-lg);
    padding-right: var(--spacing-lg);
}

.projects-grid::-webkit-scrollbar {
    display: none;
}

.project-card {
    background-color: var(--background-primary);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    border: 1px solid rgba(0, 0, 0, 0.04);
    flex: 0 0 auto;
    width: 420px;
    scroll-snap-align: start;
    display: flex;
    flex-direction: column;
}

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

.project-content {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.project-title {
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    font-size: var(--font-size-xl);
    font-weight: 600;
}

.project-description {
    margin-bottom: var(--spacing-lg);
    line-height: 1.47059;
    color: var(--text-secondary);
    flex-grow: 1;
}

.project-technologies {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-lg);
}

.tech-tag {
    padding: var(--spacing-xs) var(--spacing-sm);
    background-color: var(--background-accent);
    color: var(--text-secondary);
    border-radius: 12px;
    font-size: var(--font-size-xs);
    font-weight: 500;
}

.project-links {
    display: flex;
    gap: var(--spacing-md);
    margin-top: auto;
}

.project-link {
    font-weight: 400;
    font-size: var(--font-size-sm);
    color: var(--primary-color);
}

.project-link:hover {
    text-decoration: underline;
}

/* Contact Section - Apple-inspired */
.contact-content {
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}

.contact-text {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-2xl);
    color: var(--text-secondary);
    line-height: 1.381;
}

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

.social-link {
    font-size: var(--font-size-base);
    font-weight: 400;
    padding: var(--spacing-md) var(--spacing-xl);
    border: 1px solid var(--border-color);
    border-radius: 980px;
    transition: all var(--transition-fast);
    color: var(--text-primary);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.social-link:hover {
    background-color: var(--text-primary);
    color: var(--background-primary);
    border-color: var(--text-primary);
    text-decoration: none;
    transform: scale(1.02);
}

/* Footer - Apple-inspired */
.footer {
    background-color: var(--background-accent);
    padding: var(--spacing-xl) 0;
    border-top: 1px solid var(--border-color);
}

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

.footer-text {
    color: var(--text-secondary);
    margin: 0;
    font-size: var(--font-size-sm);
}

.back-to-top {
    background: none;
    border: none;
    color: var(--primary-color);
    cursor: pointer;
    font-size: var(--font-size-sm);
    font-weight: 400;
    transition: color var(--transition-fast);
    padding: var(--spacing-xs) var(--spacing-sm);
}

.back-to-top:hover {
    color: var(--accent-color);
    text-decoration: underline;
}

.back-to-top:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 4px;
    border-radius: 4px;
}