/* ==========================================================================
   CSS Variables - Light & Dark Theme
   ========================================================================== */

:root {
    --font-main: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2rem;
    --space-xl: 3rem;
    --space-2xl: 4rem;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --transition: 200ms ease;
    --accent: #0066ff;
    --accent-light: #3385ff;
    --accent-bg: rgba(0, 102, 255, 0.1);
    --accent-secondary: #8b5cf6;
    --gradient-primary: linear-gradient(135deg, #0066ff 0%, #8b5cf6 100%);
    --gradient-accent: linear-gradient(135deg, rgba(0, 102, 255, 0.1) 0%, rgba(139, 92, 246, 0.1) 100%);
}

[data-theme="dark"] {
    --bg-primary: #0a0a0b;
    --bg-secondary: #111113;
    --bg-card: #161618;
    --bg-hover: #1c1c1f;
    --text-primary: #ffffff;
    --text-secondary: #a1a1aa;
    --text-muted: #71717a;
    --border: #27272a;
    --border-hover: #3f3f46;
    --shadow: 0 1px 3px rgba(0,0,0,0.4);
}

[data-theme="light"] {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-card: #ffffff;
    --bg-hover: #f1f3f4;
    --text-primary: #111113;
    --text-secondary: #52525b;
    --text-muted: #71717a;
    --border: #e4e4e7;
    --border-hover: #d4d4d8;
    --shadow: 0 1px 3px rgba(0,0,0,0.08);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font-main);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background var(--transition), color var(--transition);
    -webkit-font-smoothing: antialiased;
    position: relative;
    overflow-x: hidden;
}
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image:
        linear-gradient(rgba(0, 102, 255, 0.06) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 102, 255, 0.06) 1px, transparent 1px);
    background-size: 40px 40px;
    pointer-events: none;
    z-index: 0;
    opacity: 0.5;
    mask-image: radial-gradient(ellipse 100% 80% at 50% 30%, black 30%, transparent 100%);
}
body::after {
    content: '';
    position: fixed;
    bottom: -30%;
    left: -10%;
    width: 60%;
    height: 60%;
    background: radial-gradient(circle, rgba(139, 92, 246, 0.04) 0%, transparent 70%);
    pointer-events: none;
    z-index: 0;
}
main, .top-nav, .footer {
    position: relative;
    z-index: 1;
}

/* ==========================================================================
   Top Navigation
   ========================================================================== */

.top-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-sm) var(--space-lg);
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
}

.nav-logo {
    font-weight: 700;
    font-size: 1.25rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    cursor: default;
    user-select: none;
}
.nav-right { display: flex; align-items: center; gap: var(--space-md); }

.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    cursor: pointer;
    color: var(--text-secondary);
    transition: var(--transition);
}
.theme-toggle:hover { background: var(--bg-hover); color: var(--text-primary); }
.theme-toggle svg { width: 18px; height: 18px; }
[data-theme="dark"] .theme-icon-dark { display: none; }
[data-theme="dark"] .theme-icon-light { display: block; }
[data-theme="light"] .theme-icon-dark { display: block; }
[data-theme="light"] .theme-icon-light { display: none; }

.lang-switcher {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    padding: var(--space-xs) var(--space-sm);
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
}
.lang-btn {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-muted);
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    transition: var(--transition);
}
.lang-btn:hover { color: var(--text-secondary); }
.lang-btn.active { color: var(--accent); background: var(--accent-bg); }
.lang-divider { color: var(--text-muted); font-size: 0.75rem; }

/* ==========================================================================
   Main Layout
   ========================================================================== */

main {
    max-width: 900px;
    margin: 0 auto;
    padding: calc(80px + var(--space-xl)) var(--space-lg) var(--space-xl);
}
.section { margin-bottom: var(--space-2xl); }
.section-title {
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-muted);
    margin-bottom: var(--space-lg);
}
.section-text {
    font-size: 1.1rem;
    color: var(--text-secondary);
    line-height: 1.7;
    max-width: 700px;
}

/* ==========================================================================
   Hero Section
   ========================================================================== */

.hero {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: var(--space-xl);
    align-items: center;
    padding: var(--space-xl) 0;
    margin-bottom: var(--space-xl);
}
.hero-content { display: flex; flex-direction: column; gap: var(--space-sm); }
.status { display: inline-flex; align-items: center; gap: var(--space-xs); font-size: 0.85rem; color: var(--text-secondary); }
.status-dot { width: 8px; height: 8px; background: #22c55e; border-radius: 50%; animation: pulse 2s ease-in-out infinite; }
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
.name {
    font-size: clamp(2.5rem, 6vw, 3.5rem);
    font-weight: 700;
    line-height: 1.1;
    letter-spacing: -0.02em;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    background-size: 200% 200%;
    animation: gradient-shift 5s ease infinite;
}
@keyframes gradient-shift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}
.tagline { font-size: 1.25rem; color: var(--text-secondary); }
.location { display: flex; align-items: center; gap: var(--space-xs); color: var(--text-muted); font-size: 0.9rem; }
.location svg { width: 16px; height: 16px; }
.hero-links { display: flex; gap: var(--space-sm); margin-top: var(--space-sm); }

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    padding: 0.75rem 1.25rem;
    font-size: 0.9rem;
    font-weight: 500;
    text-decoration: none;
    border-radius: var(--radius-md);
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}
.btn svg { width: 16px; height: 16px; position: relative; z-index: 1; }
.btn span { position: relative; z-index: 1; }
.btn-primary {
    background: var(--gradient-primary);
    color: #fff;
    border: none;
    background-size: 200% 200%;
}
.btn-primary::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient-primary);
    opacity: 0;
    transition: opacity 0.3s ease;
    filter: brightness(1.2);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0, 102, 255, 0.3);
}
.btn-primary:hover::before {
    opacity: 1;
}
.btn-secondary {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border);
}
.btn-secondary:hover {
    background: var(--bg-hover);
    border-color: var(--accent);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 102, 255, 0.1);
}

.profile-photo-container {
    width: 180px;
    height: 180px;
    flex-shrink: 0;
    position: relative;
}
.profile-photo-container::before {
    content: '';
    position: absolute;
    inset: -3px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    opacity: 0.6;
    z-index: -1;
}
.profile-photo {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: var(--radius-lg);
    border: 3px solid var(--bg-primary);
    position: relative;
    z-index: 1;
    transition: transform var(--transition);
}
.profile-photo:hover { transform: scale(1.02); }

/* ==========================================================================
   Freelance Projects
   ========================================================================== */

.freelance-grid { display: grid; gap: var(--space-md); }
.freelance-card {
    padding: var(--space-lg);
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}
.freelance-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient-accent);
    opacity: 0;
    transition: opacity 0.3s ease;
    z-index: 0;
}
.freelance-card:hover {
    border-color: var(--accent);
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(0, 102, 255, 0.18);
}
.freelance-card:hover::before {
    opacity: 1;
}
.freelance-card > * { position: relative; z-index: 1; }
.freelance-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: var(--space-sm); }
.freelance-meta { display: flex; align-items: center; gap: var(--space-sm); }
.freelance-year { font-family: var(--font-mono); font-size: 0.75rem; color: var(--accent); background: var(--accent-bg); padding: 0.2rem 0.5rem; border-radius: 4px; }
.freelance-client { font-size: 0.85rem; color: var(--text-muted); }
.freelance-link { display: flex; align-items: center; justify-content: center; width: 32px; height: 32px; color: var(--text-muted); transition: var(--transition); }
.freelance-link:hover { color: var(--accent); }
.freelance-link svg { width: 16px; height: 16px; }
.freelance-card h3 { font-size: 1.1rem; font-weight: 600; margin-bottom: var(--space-xs); }
.freelance-card p { font-size: 0.9rem; color: var(--text-secondary); line-height: 1.6; margin-bottom: var(--space-md); }
.freelance-tech { display: flex; flex-wrap: wrap; gap: var(--space-xs); }
.freelance-tech span { font-family: var(--font-mono); font-size: 0.7rem; padding: 0.25rem 0.5rem; background: var(--bg-secondary); border: 1px solid var(--border); border-radius: 4px; color: var(--text-secondary); }

/* ==========================================================================
   Services
   ========================================================================== */

.services-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-md); }
.service-card {
    padding: var(--space-lg);
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}
.service-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient-accent);
    opacity: 0;
    transition: opacity 0.3s ease;
    z-index: 0;
}
.service-card:hover {
    border-color: var(--accent);
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(0, 102, 255, 0.18);
}
.service-card:hover::before {
    opacity: 1;
}
.service-card > * { position: relative; z-index: 1; }
.service-icon { width: 24px; height: 24px; color: var(--accent); margin-bottom: var(--space-md); }
.service-card h3 { font-size: 1rem; font-weight: 600; margin-bottom: var(--space-xs); }
.service-card p { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.5; }

/* ==========================================================================
   Timeline
   ========================================================================== */

.timeline { display: flex; flex-direction: column; gap: var(--space-md); position: relative; }
.timeline::before {
    content: '';
    position: absolute;
    left: 6px;
    top: 18px;
    bottom: 18px;
    width: 2px;
    background: var(--border);
}
.timeline-item { display: grid; grid-template-columns: 12px 1fr; gap: var(--space-md); position: relative; }
.timeline-marker { width: 12px; height: 12px; background: var(--bg-primary); border: 2px solid var(--accent); border-radius: 50%; margin-top: 6px; position: relative; z-index: 1; }
.timeline-marker.edu { border-color: #8b5cf6; }
.timeline-content { padding-bottom: var(--space-md); border-bottom: 1px solid var(--border); }
.timeline-item:last-child .timeline-content { border-bottom: none; padding-bottom: 0; }
.timeline-date { font-family: var(--font-mono); font-size: 0.75rem; color: var(--text-muted); }
.timeline-content h3 { font-size: 1rem; font-weight: 600; margin: var(--space-xs) 0; }
.timeline-company { font-size: 0.9rem; color: var(--accent); margin-bottom: var(--space-xs); }
.timeline-desc { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.5; }

/* ==========================================================================
   Tech Stack
   ========================================================================== */

.tech-grid { display: flex; flex-direction: column; gap: var(--space-lg); }
.tech-category h3 { font-size: 0.75rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.05em; color: var(--text-muted); margin-bottom: var(--space-sm); }
.tech-tags { display: flex; flex-wrap: wrap; gap: var(--space-xs); }
.tech-tags span { font-family: var(--font-mono); font-size: 0.8rem; padding: 0.4rem 0.75rem; background: var(--bg-secondary); border: 1px solid var(--border); border-radius: var(--radius-sm); color: var(--text-secondary); transition: var(--transition); }
.tech-tags span:hover { border-color: var(--accent); color: var(--accent); }

/* ==========================================================================
   Projects
   ========================================================================== */

.projects-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--space-md); margin-bottom: var(--space-lg); }
.project-card {
    display: flex;
    flex-direction: column;
    padding: var(--space-md);
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    text-decoration: none;
    color: inherit;
    transition: all var(--transition);
    position: relative;
    overflow: hidden;
}
.project-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient-accent);
    opacity: 0;
    transition: opacity 0.3s ease;
    z-index: 0;
}
.project-card:hover {
    border-color: var(--accent);
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(0, 102, 255, 0.18);
}
.project-card:hover::before {
    opacity: 1;
}
.project-card > * { position: relative; z-index: 1; }
.project-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: var(--space-sm); }
.project-icon { width: 20px; height: 20px; color: var(--text-muted); }
.project-lang { font-family: var(--font-mono); font-size: 0.65rem; padding: 0.2rem 0.4rem; background: var(--bg-secondary); border-radius: 4px; color: var(--text-muted); }
.project-card h3 { font-size: 1rem; font-weight: 600; margin-bottom: var(--space-xs); }
.project-card p { font-size: 0.85rem; color: var(--text-secondary); flex-grow: 1; }
.project-stars { display: flex; align-items: center; gap: 4px; font-family: var(--font-mono); font-size: 0.75rem; color: var(--text-muted); margin-top: var(--space-sm); }
.project-stars svg { width: 14px; height: 14px; }

.link-more { display: inline-flex; align-items: center; gap: var(--space-xs); font-size: 0.9rem; color: var(--accent); text-decoration: none; transition: var(--transition); }
.link-more:hover { gap: var(--space-sm); }
.link-more svg { width: 16px; height: 16px; }

/* ==========================================================================
   Contact
   ========================================================================== */

.contact-links { display: flex; flex-wrap: wrap; gap: var(--space-sm); margin-top: var(--space-md); }
.contact-link { display: inline-flex; align-items: center; gap: var(--space-sm); padding: var(--space-sm) var(--space-md); background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-md); color: var(--text-secondary); text-decoration: none; transition: var(--transition); }
.contact-link:hover { color: var(--text-primary); border-color: var(--border-hover); background: var(--bg-hover); }
.contact-link svg { width: 18px; height: 18px; }

/* ==========================================================================
   Footer
   ========================================================================== */

.footer { padding: var(--space-xl) var(--space-lg); text-align: center; border-top: 1px solid var(--border); margin-top: var(--space-xl); }
.footer-main p { font-size: 0.85rem; color: var(--text-muted); }
.footer-vat { font-family: var(--font-mono); font-size: 0.75rem !important; margin-top: var(--space-xs); }
.footer-links { display: flex; justify-content: center; gap: var(--space-sm); margin-top: var(--space-md); }
.footer-links a { font-size: 0.8rem; color: var(--text-muted); text-decoration: none; transition: var(--transition); }
.footer-links a:hover { color: var(--accent); }
.footer-links span { color: var(--text-muted); }

/* ==========================================================================
   Modal
   ========================================================================== */

.modal { display: none; position: fixed; inset: 0; z-index: 200; background: rgba(0,0,0,0.6); backdrop-filter: blur(4px); align-items: center; justify-content: center; padding: var(--space-lg); }
.modal.active { display: flex; }
.modal-content { position: relative; max-width: 600px; max-height: 80vh; overflow-y: auto; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: var(--space-xl); }
.modal-close { position: absolute; top: var(--space-md); right: var(--space-md); width: 32px; height: 32px; display: flex; align-items: center; justify-content: center; background: var(--bg-secondary); border: 1px solid var(--border); border-radius: var(--radius-sm); cursor: pointer; color: var(--text-secondary); transition: var(--transition); }
.modal-close:hover { color: var(--text-primary); }
.modal-close svg { width: 18px; height: 18px; }
.modal-content h2 { font-size: 1.5rem; margin-bottom: var(--space-lg); padding-right: 40px; }
.modal-body h3 { font-size: 1rem; font-weight: 600; margin: var(--space-lg) 0 var(--space-sm); }
.modal-body p { font-size: 0.9rem; color: var(--text-secondary); line-height: 1.6; margin-bottom: var(--space-sm); }
.modal-body ul { margin-left: var(--space-lg); color: var(--text-secondary); font-size: 0.9rem; }
.modal-body li { margin-bottom: var(--space-xs); }

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 768px) {
    .hero { grid-template-columns: 1fr; text-align: center; }
    .hero-content { align-items: center; }
    .hero-visual {
        order: -1;
        display: flex;
        justify-content: center;
        width: 100%;
    }
    .profile-photo-container { width: 140px; height: 140px; margin: 0 auto; }
    .status { justify-content: center; }
    .hero-links { justify-content: center; }
    .services-grid, .projects-grid { grid-template-columns: 1fr; }
    .top-nav { padding: var(--space-sm); }
    main { padding-left: var(--space-sm); padding-right: var(--space-sm); }
}

@media (max-width: 480px) {
    .name { font-size: 2rem; }
    .contact-links { flex-direction: column; }
    .contact-link { justify-content: center; }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
::selection { background: var(--accent); color: #fff; }