/* ========================================
   CSS Reset & Base Styles
   ======================================== */

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

/* Common variables (non-color) */
:root {
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;

    /* Typography */
    --font-sans: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'Courier New', monospace;

    /* Transitions */
    --transition-base: all 0.3s ease;
    --transition-fast: all 0.15s ease;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.6);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    letter-spacing: 0.02em;
    font-size: 20px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ========================================
   Header & Navigation
   ======================================== */

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(10, 10, 10, 0.9);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-md) 0;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
}

.logo-link {
    text-decoration: none;
    color: inherit;
}

.logo-text {
    color: var(--text-primary);
    font-weight: 700;
    font-size: 2rem;
    letter-spacing: 0.02em;
}

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

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: 1.25rem;
    transition: var(--transition-base);
    position: relative;
    letter-spacing: 0.03em;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-gradient);
    transition: width 0.3s ease;
}

.nav-link:hover {
    color: var(--text-primary);
}

.nav-link:hover::after {
    width: 100%;
}

.lang-switcher {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 0.9rem;
    transition: var(--transition-base);
}

.lang-active {
    color: var(--accent-primary);
    font-weight: bold;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 3px;
    transition: var(--transition-base);
}

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

.hero {
    padding: calc(var(--spacing-3xl) + 60px) 0 var(--spacing-3xl);
    background: linear-gradient(135deg, #0a0a0a 0%, #1a1a1a 50%, #0a0a0a 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--hero-gradient);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.hero-title {
    font-size: clamp(3rem, 7vw, 4.5rem);
    font-weight: 900;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    letter-spacing: -0.01em;
}

.highlight {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1.25rem, 2.5vw, 1.5rem);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
    line-height: 1.8;
}

.hero-social {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    margin-bottom: var(--spacing-lg);
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    color: var(--text-secondary);
    transition: var(--transition-base);
    cursor: pointer;
}

.social-link:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.social-icon {
    width: 28px;
    height: 28px;
}

.hero-features {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    flex-wrap: wrap;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--success-color);
    font-weight: 500;
}

.feature-icon {
    width: 24px;
    height: 24px;
}

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

.btn {
    display: inline-block;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition-base);
    cursor: pointer;
    border: 2px solid transparent;
}

.btn-primary {
    background: var(--accent-gradient);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: transparent;
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.btn-secondary:hover {
    background: var(--accent-primary);
    color: white;
}

/* ========================================
   About Section
   ======================================== */

.about {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-primary);
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-text {
    font-size: 1.2rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

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

.services {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-secondary);
}

.section-title {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-xl);
    letter-spacing: -0.01em;
}

.section-subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.3rem;
    margin-bottom: var(--spacing-xl);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.service-card {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-xl);
    transition: var(--transition-base);
}

.service-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
    border-color: var(--accent-primary);
}

.service-icon {
    width: 48px;
    height: 48px;
    color: var(--accent-primary);
    margin-bottom: var(--spacing-md);
}

.service-title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.service-description {
    color: var(--text-secondary);
    line-height: 1.8;
    font-size: 1.1rem;
}

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

.projects {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-secondary);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.project-card {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-xl);
    transition: var(--transition-base);
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
    border-color: var(--accent-primary);
}

.project-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--accent-primary);
}

.project-description {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-md);
}

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

.project-stat {
    display: flex;
    flex-direction: column;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-primary);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* ========================================
   Skills Section
   ======================================== */

.skills {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-primary);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

.skill-category {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-lg);
}

.skill-category-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    color: var(--accent-primary);
}

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

.skill-tag {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: 6px;
    font-size: 0.9rem;
    transition: var(--transition-fast);
}

.skill-tag:hover {
    background: var(--accent-primary);
    color: white;
    transform: scale(1.05);
}

/* ========================================
   References Section
   ======================================== */

.references {
    padding: var(--spacing-3xl) 0;
    background: var(--bg-secondary);
}

.references-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
    max-width: 900px;
    margin: 0 auto;
}

.reference-logo {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-base);
    min-height: 120px;
}

.reference-logo:hover {
    transform: scale(1.05);
    border-color: var(--accent-primary);
}

.reference-logo img {
    max-width: 100%;
    height: auto;
    max-height: 80px;
    object-fit: contain;
}

.grayscale-logo {
    filter: grayscale(100%);
    opacity: 0.7;
    transition: var(--transition-base);
}

.reference-logo:hover .grayscale-logo {
    filter: grayscale(0%);
    opacity: 1;
}

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

.contact {
    padding: var(--spacing-3xl) 0;
    background: linear-gradient(135deg, #0a0a0a 0%, #1a1a1a 100%);
}

.contact-content {
    max-width: 700px;
    margin: 0 auto;
    text-align: center;
}

.contact-title {
    font-size: clamp(2.25rem, 5vw, 3rem);
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.contact-description {
    color: var(--text-secondary);
    font-size: 1.2rem;
    margin-bottom: var(--spacing-xl);
    line-height: 1.8;
}

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

.contact-social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    color: var(--text-secondary);
    transition: var(--transition-base);
    cursor: pointer;
    text-decoration: none;
}

.contact-social-link:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.contact-social-icon {
    width: 40px;
    height: 40px;
}

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

.footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-xl) 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

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

.footer-link {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition-base);
}

.footer-link:hover {
    color: var(--accent-primary);
}

/* ========================================
   Theme Switcher
   ======================================== */

.theme-switcher {
    position: fixed;
    bottom: var(--spacing-lg);
    right: var(--spacing-lg);
    z-index: 999;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-md);
    box-shadow: var(--shadow-xl);
    display: none; /* Skrytá paleta barev */
}

.theme-switcher-title {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-secondary);
    text-align: center;
}

.theme-options {
    display: flex;
    gap: var(--spacing-xs);
    flex-wrap: wrap;
    justify-content: center;
}

.theme-option {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 3px solid transparent;
    cursor: pointer;
    transition: var(--transition-fast);
    position: relative;
}

.theme-option:hover {
    transform: scale(1.1);
}

.theme-option.active {
    border-color: var(--text-primary);
    box-shadow: 0 0 0 2px var(--bg-secondary);
}

.theme-option[data-theme="orange"] {
    background: linear-gradient(135deg, #ff8c42 0%, #ffa560 100%);
}

.theme-option[data-theme="blue"] {
    background: linear-gradient(135deg, #3b82f6 0%, #60a5fa 100%);
}

.theme-option[data-theme="green"] {
    background: linear-gradient(135deg, #10b981 0%, #34d399 100%);
}

.theme-option[data-theme="purple"] {
    background: linear-gradient(135deg, #8b5cf6 0%, #a78bfa 100%);
}

.theme-option[data-theme="red"] {
    background: linear-gradient(135deg, #ef4444 0%, #f87171 100%);
}

.theme-option[data-theme="cyan"] {
    background: linear-gradient(135deg, #06b6d4 0%, #22d3ee 100%);
}

.theme-option[data-theme="teal"] {
    background: linear-gradient(135deg, #14b8a6 0%, #2dd4bf 100%);
}

/* ========================================
   Cookie Consent Banner
   ======================================== */

.cookie-consent {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    border-top: 2px solid var(--accent-primary);
    padding: var(--spacing-lg);
    z-index: 9999;
    transform: translateY(100%);
    transition: transform 0.3s ease-out;
    box-shadow: 0 -4px 12px rgba(0, 0, 0, 0.5);
}

.cookie-consent.show {
    transform: translateY(0);
}

.cookie-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--spacing-lg);
}

.cookie-text {
    flex: 1;
}

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

.cookie-description {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin: 0;
}

.cookie-buttons {
    display: flex;
    gap: var(--spacing-sm);
    flex-shrink: 0;
}

.cookie-btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    transition: var(--transition-base);
    border: 2px solid transparent;
    white-space: nowrap;
}

.cookie-accept {
    background: var(--accent-gradient);
    color: white;
    border: none;
}

.cookie-accept:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.cookie-decline {
    background: transparent;
    border-color: var(--border-color);
    color: var(--text-secondary);
}

.cookie-decline:hover {
    border-color: var(--text-secondary);
    color: var(--text-primary);
}

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

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--bg-secondary);
        flex-direction: column;
        padding: var(--spacing-lg);
        border-bottom: 1px solid var(--border-color);
        transform: translateY(-100%);
        opacity: 0;
        transition: var(--transition-base);
        pointer-events: none;
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        pointer-events: all;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .mobile-menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -7px);
    }

    .hero {
        padding: calc(var(--spacing-2xl) + 60px) 0 var(--spacing-2xl);
    }

    .hero-features {
        flex-direction: column;
        align-items: center;
    }

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

    .btn {
        width: 100%;
        text-align: center;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }

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

    .references-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .theme-switcher {
        bottom: var(--spacing-sm);
        right: var(--spacing-sm);
        padding: var(--spacing-sm);
    }

    .theme-option {
        width: 35px;
        height: 35px;
    }
}

@media (max-width: 480px) {
    :root {
        --spacing-xl: 2rem;
        --spacing-2xl: 3rem;
        --spacing-3xl: 4rem;
    }

    .service-card,
    .skill-category,
    .project-card,
    .reference-logo {
        padding: var(--spacing-md);
    }
}

/* Cookie consent responsive */
@media (max-width: 768px) {
    .cookie-consent {
        padding: var(--spacing-md);
    }

    .cookie-content {
        flex-direction: column;
        text-align: center;
    }

    .cookie-buttons {
        width: 100%;
        flex-direction: column;
    }

    .cookie-btn {
        width: 100%;
    }
}

/* ========================================
   Animations
   ======================================== */

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

.hero-content,
.service-card,
.skill-category,
.project-card,
.reference-logo {
    animation: fadeInUp 0.6s ease-out;
}

.service-card:nth-child(1) { animation-delay: 0.1s; }
.service-card:nth-child(2) { animation-delay: 0.2s; }
.service-card:nth-child(3) { animation-delay: 0.3s; }
.service-card:nth-child(4) { animation-delay: 0.4s; }

/* Smooth scroll offset for fixed header */
section {
    scroll-margin-top: 80px;
}

@keyframes slideUp {
    from {
        transform: translateY(100%);
    }
    to {
        transform: translateY(0);
    }
}

/* ========================================
   Copy Notification
   ======================================== */

.copy-notification {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: var(--primary-600);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 8px;
    box-shadow: var(--shadow-lg);
    font-size: 0.9rem;
    font-weight: 500;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.3s ease;
    z-index: 9999;
    pointer-events: none;
}

.copy-notification.show {
    opacity: 1;
    transform: translateY(0);
}

@media (max-width: 768px) {
    .copy-notification {
        bottom: 1rem;
        right: 1rem;
        left: 1rem;
        text-align: center;
    }
}