/* Design System for artur.ledwig.net */
:root {
    --font-heading: 'Outfit', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --font-body: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;

    /* Tech-oriented palette: Deep Indigo/Navy with neon Cyan/Blue accents */
    --bg-main: #060813;
    --bg-radial: radial-gradient(circle at top right, #0e1638 0%, #060813 100%);
    
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    
    --accent: #06b6d4; /* Neon Cyan */
    --accent-rgb: 6, 182, 212;
    --accent-glow: rgba(6, 182, 212, 0.4);
    
    --accent-alt: #6366f1; /* Indigo */
    --accent-alt-rgb: 99, 102, 241;
    
    --card-bg: rgba(15, 23, 42, 0.55);
    --card-border: rgba(255, 255, 255, 0.05);
    --card-border-hover: rgba(6, 182, 212, 0.25);
    
    --transition-smooth: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    width: 100%;
    min-height: 100vh;
    background-color: var(--bg-main);
    background-image: var(--bg-radial);
    color: var(--text-primary);
    font-family: var(--font-body);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Background Grid & Glow Effect */
.grid-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: 40px 40px;
    background-image: linear-gradient(to right, rgba(255, 255, 255, 0.015) 1px, transparent 1px),
                      linear-gradient(to bottom, rgba(255, 255, 255, 0.015) 1px, transparent 1px);
    z-index: 0;
    pointer-events: none;
}

.light-effect {
    position: fixed;
    top: -10%;
    right: 10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(var(--accent-rgb), 0.12) 0%, transparent 70%);
    z-index: 0;
    pointer-events: none;
    filter: blur(80px);
}

/* Page Wrapper */
.page-container {
    position: relative;
    z-index: 1;
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem 1.5rem;
}

/* Navigation bar */
.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 5rem;
}

.back-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 99px;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition-smooth);
}

.back-link:hover {
    color: var(--accent);
    border-color: rgba(var(--accent-rgb), 0.3);
    background: rgba(var(--accent-rgb), 0.05);
}

.brand {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.25rem;
    letter-spacing: -0.02em;
    color: var(--text-primary);
    position: relative;
}

.brand::after {
    content: '';
    position: absolute;
    bottom: 2px;
    right: -6px;
    width: 4px;
    height: 4px;
    background: var(--accent);
    border-radius: 50%;
}

/* Hero Section */
.hero {
    margin-bottom: 6rem;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.role-badge {
    display: inline-block;
    font-family: var(--font-heading);
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--accent);
    background: rgba(var(--accent-rgb), 0.1);
    border: 1px solid rgba(var(--accent-rgb), 0.2);
    padding: 0.4rem 1rem;
    border-radius: 99px;
    margin-bottom: 1.5rem;
}

.hero h1 {
    font-family: var(--font-heading);
    font-size: 4rem;
    font-weight: 700;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 1.5rem;
    background: linear-gradient(to right, #ffffff, #94a3b8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.tagline {
    font-size: 1.25rem;
    font-weight: 300;
    color: var(--text-secondary);
    max-width: 700px;
    line-height: 1.6;
    margin-bottom: 2.5rem;
}

.highlight {
    color: var(--text-primary);
    font-weight: 500;
    position: relative;
    display: inline-block;
}

.highlight::after {
    content: '';
    position: absolute;
    bottom: 2px;
    left: 0;
    width: 100%;
    height: 1px;
    background: rgba(var(--accent-rgb), 0.5);
}

.cta-group {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.8rem 1.8rem;
    border-radius: 12px;
    font-weight: 500;
    font-size: 0.95rem;
    text-decoration: none;
    transition: var(--transition-smooth);
}

.btn-primary {
    background: var(--accent);
    color: #000000;
    box-shadow: 0 4px 20px rgba(var(--accent-rgb), 0.2);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(var(--accent-rgb), 0.35);
    background: #0ae6ff;
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.03);
    color: var(--text-primary);
    border: 1px solid rgba(255, 255, 255, 0.08);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.15);
    transform: translateY(-2px);
}

/* Sections General */
.section {
    margin-bottom: 6rem;
}

.section h2 {
    font-family: var(--font-heading);
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: 2.5rem;
    letter-spacing: -0.02em;
    position: relative;
    display: inline-block;
}

.section h2::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 40px;
    height: 2px;
    background: var(--accent);
}

/* Timeline Layout */
.timeline {
    position: relative;
    border-left: 2px solid rgba(255, 255, 255, 0.06);
    padding-left: 2.5rem;
    margin-left: 0.5rem;
}

.timeline-item {
    position: relative;
    margin-bottom: 3.5rem;
}

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

.timeline-dot {
    position: absolute;
    left: calc(-2.5rem - 7px);
    top: 6px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 10px var(--accent);
    border: 2px solid var(--bg-main);
    transition: var(--transition-smooth);
}

.timeline-item:hover .timeline-dot {
    transform: scale(1.3);
    background: var(--text-primary);
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.8);
}

.timeline-date {
    font-family: var(--font-heading);
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--accent);
    margin-bottom: 0.5rem;
    letter-spacing: 0.02em;
}

.timeline-content {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 1.75rem;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    transition: var(--transition-smooth);
}

.timeline-content h3 {
    font-family: var(--font-heading);
    font-size: 1.35rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.timeline-content .company {
    display: inline-block;
    font-size: 0.9rem;
    color: var(--text-muted);
    font-weight: 500;
    margin-bottom: 1rem;
}

.timeline-content p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    font-weight: 300;
}

.timeline-item:hover .timeline-content {
    border-color: var(--card-border-hover);
    box-shadow: 0 15px 35px -10px rgba(0, 0, 0, 0.4),
                0 0 20px rgba(var(--accent-rgb), 0.05);
    transform: translateX(4px);
}

/* Skills Section */
.skills-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

@media (max-width: 768px) {
    .skills-grid {
        grid-template-columns: 1fr;
    }
}

.skill-category {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 20px;
    padding: 2rem;
    backdrop-filter: blur(12px);
}

.skill-category h3 {
    font-family: var(--font-heading);
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    padding-bottom: 0.75rem;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.tag {
    font-size: 0.85rem;
    font-weight: 500;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.06);
    color: var(--text-secondary);
    padding: 0.45rem 1rem;
    border-radius: 99px;
    transition: var(--transition-smooth);
}

.tag:hover {
    color: var(--accent);
    background: rgba(var(--accent-rgb), 0.08);
    border-color: rgba(var(--accent-rgb), 0.3);
    box-shadow: 0 0 12px rgba(var(--accent-rgb), 0.15);
    transform: translateY(-2px);
}

/* Contact Section */
.contact-section {
    text-align: center;
}

.contact-section p {
    color: var(--text-secondary);
    font-weight: 300;
    margin-bottom: 2rem;
}

.contact-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.contact-card {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 1.25rem 2rem;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    font-size: 0.95rem;
    transition: var(--transition-smooth);
    backdrop-filter: blur(12px);
}

.contact-icon {
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    transition: var(--transition-smooth);
}

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

.contact-card:hover {
    border-color: var(--card-border-hover);
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.4),
                0 0 15px rgba(var(--accent-rgb), 0.08);
    transform: translateY(-3px);
}

.contact-card:hover .contact-icon {
    color: var(--accent);
    transform: scale(1.1);
}

/* Footer Styling */
.footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 2rem;
    margin-top: 5rem;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    color: var(--text-muted);
    font-size: 0.85rem;
}

.home-ref a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition-smooth);
}

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

/* Responsive Rules */
@media (max-width: 768px) {
    .nav {
        margin-bottom: 3.5rem;
    }
    
    .hero {
        margin-bottom: 4rem;
    }
    
    .hero h1 {
        font-size: 2.8rem;
    }
    
    .tagline {
        font-size: 1.1rem;
    }
    
    .timeline {
        padding-left: 1.75rem;
    }
    
    .timeline-dot {
        left: calc(-1.75rem - 7px);
    }
    
    .contact-links {
        flex-direction: column;
        align-items: stretch;
    }
    
    .footer {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
}