/* ============================================
   RESET & BASE
   ============================================ */

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

:root {
    --color-black: #1d1d1f;
    --color-gray-900: #2c2c2e;
    --color-gray-700: #48484a;
    --color-gray-500: #86868b;
    --color-gray-300: #d1d1d6;
    --color-gray-100: #f5f5f7;
    --color-white: #ffffff;
    --color-accent: #0071e3;
    --color-accent-hover: #0077ed;

    --font-system: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'SF Pro Text', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    --font-mono: 'SF Mono', SFMono-Regular, 'Consolas', 'Liberation Mono', Menlo, monospace;

    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 3rem;
    --space-xl: 5rem;
    --space-2xl: 8rem;

    --max-width: 1200px;
    --max-width-narrow: 900px;

    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.6s ease;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-system);
    font-size: 17px;
    line-height: 1.65;
    color: var(--color-black);
    background-color: var(--color-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: inherit;
    text-decoration: none;
}

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

/* ============================================
   LAYOUT
   ============================================ */

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
}

.container--narrow {
    max-width: var(--max-width-narrow);
}

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

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.04);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
    height: 52px;
}

.nav-left, .nav-right {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-name {
    font-size: 14px;
    font-weight: 600;
    color: var(--color-black);
    letter-spacing: -0.02em;
    margin-right: 1rem;
}

.nav-link {
    font-size: 14px;
    font-weight: 400;
    color: var(--color-gray-700);
    transition: color var(--transition-fast);
    letter-spacing: -0.01em;
}

.nav-link:hover,
.nav-link:focus-visible {
    color: var(--color-black);
}

.nav-link:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 4px;
    border-radius: 2px;
}

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

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 52px;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: 4rem;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
    width: 100%;
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 600;
    line-height: 1.1;
    letter-spacing: -0.03em;
    color: var(--color-black);
}

.hero-line {
    display: block;
}

.hero-subtitle {
    margin-top: 1.5rem;
    font-size: 1.125rem;
    line-height: 1.6;
    color: var(--color-gray-500);
    max-width: 520px;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    margin-top: 2.5rem;
}

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

.hero-svg {
    width: 100%;
    max-width: 380px;
    height: auto;
    opacity: 0.7;
}

/* ============================================
   BUTTONS
   ============================================ */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 15px;
    font-weight: 400;
    border-radius: 980px;
    padding: 0.75rem 1.75rem;
    transition: all var(--transition-fast);
    cursor: pointer;
    border: none;
    letter-spacing: -0.01em;
}

.btn:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 3px;
}

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

.btn-primary:hover {
    background-color: var(--color-gray-900);
}

.btn-secondary {
    background-color: transparent;
    color: var(--color-black);
    border: 1px solid var(--color-gray-300);
}

.btn-secondary:hover {
    background-color: var(--color-gray-100);
}

.btn-tertiary {
    padding: 0;
    font-size: 15px;
    color: var(--color-accent);
    background: none;
    border-radius: 0;
}

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

/* ============================================
   SECTIONS
   ============================================ */

.section-title {
    font-size: 2.5rem;
    font-weight: 600;
    letter-spacing: -0.025em;
    margin-bottom: var(--space-lg);
    color: var(--color-black);
}

.featured,
.about,
.skills,
.projects,
.contact {
    padding: var(--space-2xl) 0;
}

.featured {
    background-color: var(--color-gray-100);
}

/* ============================================
   FEATURED PROJECTS
   ============================================ */

.featured-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.featured-cta {
    text-align: center;
    margin-top: var(--space-lg);
}

/* ============================================
   PROJECT CARDS
   ============================================ */

.project-card {
    background: var(--color-white);
    border-radius: 16px;
    overflow: hidden;
    transition: transform var(--transition-base), box-shadow var(--transition-base);
    border: 1px solid rgba(0, 0, 0, 0.04);
}

.project-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.06);
}

.project-card-content {
    padding: 2rem;
}

.project-card-meta {
    font-size: 13px;
    color: var(--color-gray-500);
    margin-bottom: 0.75rem;
}

.project-card-title {
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 0.75rem;
    color: var(--color-black);
}

.project-card-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.tech-tag {
    font-size: 12px;
    font-weight: 500;
    padding: 0.25rem 0.625rem;
    background-color: var(--color-gray-100);
    color: var(--color-gray-700);
    border-radius: 4px;
    letter-spacing: -0.01em;
}

.featured .tech-tag {
    background-color: var(--color-gray-100);
}

.project-card-desc {
    font-size: 15px;
    line-height: 1.6;
    color: var(--color-gray-500);
    margin-bottom: 1.25rem;
}

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

.about-content::after {
    content: '';
    display: table;
    clear: both;
}

.about-photo {
    float: left;
    width: 180px;
    height: 180px;
    aspect-ratio: 1 / 1;
    object-fit: cover;
    border-radius: 8px;
    margin-right: var(--space-md);
    margin-bottom: var(--space-sm);
}

.about-content p {
    font-size: 1.0625rem;
    line-height: 1.7;
    color: var(--color-gray-700);
    margin-bottom: 1.25rem;
}

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

@media (max-width: 640px) {
    .about-photo {
        float: none;
        display: block;
        margin: 0 auto var(--space-md);
        width: 140px;
        height: 140px;
    }
}

/* ============================================
   SKILLS
   ============================================ */

.skills {
    background-color: var(--color-gray-100);
}

.skills-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    justify-content: center;
}

.skill-badge {
    font-size: 15px;
    font-weight: 500;
    padding: 0.625rem 1.25rem;
    background-color: var(--color-white);
    color: var(--color-gray-700);
    border-radius: 980px;
    border: 1px solid rgba(0, 0, 0, 0.06);
    letter-spacing: -0.01em;
    transition: border-color var(--transition-fast), color var(--transition-fast);
}

.skill-badge:hover {
    border-color: var(--color-gray-300);
    color: var(--color-black);
}

/* ============================================
   ALL PROJECTS GRID
   ============================================ */

.projects-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.projects .project-card {
    border: 1px solid rgba(0, 0, 0, 0.06);
}

/* ============================================
   PROJECTS PAGE
   ============================================ */

.projects-page {
    padding-top: calc(52px + 5rem);
    padding-bottom: var(--space-2xl);
}

.projects-page-title {
    margin-bottom: var(--space-lg);
}

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

.contact {
    text-align: center;
}

.contact-text {
    font-size: 1.0625rem;
    color: var(--color-gray-500);
    margin-bottom: 2rem;
    line-height: 1.6;
}

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

.footer {
    padding: var(--space-lg) 0;
    border-top: 1px solid rgba(0, 0, 0, 0.06);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 2rem;
}

.footer-name {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.footer-email a {
    font-size: 14px;
    color: var(--color-gray-500);
    transition: color var(--transition-fast);
}

.footer-email a:hover {
    color: var(--color-black);
}

.footer-links {
    display: flex;
    gap: 1.5rem;
}

.footer-links a {
    font-size: 14px;
    color: var(--color-gray-500);
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--color-black);
}

.footer-bottom {
    padding-top: 1.5rem;
    border-top: 1px solid rgba(0, 0, 0, 0.04);
}

.footer-bottom p {
    font-size: 13px;
    color: var(--color-gray-500);
}

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

.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity var(--transition-slow), transform var(--transition-slow);
}

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

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

@media (max-width: 1024px) {
    .featured-grid {
        grid-template-columns: 1fr;
        gap: 1.25rem;
    }

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

@media (max-width: 768px) {
    body {
        font-size: 16px;
    }

    .nav {
        padding: 0 1.25rem;
    }

    .nav-left, .nav-right {
        gap: 1.25rem;
    }

    .nav-link {
        font-size: 13px;
    }

    .hero-content {
        grid-template-columns: 1fr;
        padding: 0 1.25rem;
        gap: 3rem;
    }

    .hero-visual {
        display: none;
    }

    .hero-title {
        font-size: 2.25rem;
    }

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

    .container {
        padding: 0 1.25rem;
    }

    .featured,
    .about,
    .skills,
    .projects,
    .contact {
        padding: var(--space-xl) 0;
    }

    .footer-content {
        flex-direction: column;
        gap: 1.5rem;
    }
}

@media (max-width: 480px) {
    .nav-right {
        gap: 1rem;
    }

    .hero-title {
        font-size: 1.875rem;
    }

    .hero-actions {
        flex-direction: column;
    }

    .hero-actions .btn {
        width: 100%;
    }
}

/* ============================================
   REDUCED MOTION
   ============================================ */

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    .fade-in {
        opacity: 1;
        transform: none;
        transition: none;
    }

    .project-card:hover {
        transform: none;
    }
}