/* 1. PROMĚNNÉ A ZÁKLAD */
:root {
    /* --- SVĚTLÝ REŽIM (LIGHT MODE) --- */
    --bg-body: #ffffff;
    --bg-alt: #f0f4f8; 
    --bg-card: #ffffff;
    --bg-footer: #e2e8f0;
    
    --bg-glass: rgba(255, 255, 255, 0.8);
    --bg-icon: #f1f5f9;
    
    --text-main: #0f172a;
    --text-muted: #64748b;
    
    --accent: #5e81ac;
    --accent-hover: #4c6a8f;
    --accent-light: #88c0d0;
    
    --shadow-card: 0 25px 50px -12px rgba(0, 0, 0, 0.08);
    --shadow-nav: 0 10px 30px rgba(0, 0, 0, 0.05);
    
    --border-color: rgba(0,0,0,0.05);
    --transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

/* --- TMAVÝ REŽIM (DARK MODE) --- */
[data-theme="dark"] {
    --bg-body: #0f172a;
    --bg-alt: #162032; 
    --bg-card: #1e293b;
    --bg-footer: #020617;
    
    --bg-glass: rgba(15, 23, 42, 0.85);
    --bg-icon: #334155;
    
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    
    --accent: #88c0d0;
    --accent-hover: #81a1c1;
    
    --shadow-card: 0 20px 40px rgba(0, 0, 0, 0.4);
    --shadow-nav: 0 10px 30px rgba(0, 0, 0, 0.2);
    
    --border-color: rgba(255,255,255,0.05);
}

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

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', sans-serif;
    background: var(--bg-body);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
    transition: background 0.5s ease, color 0.5s ease;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.text-accent { color: var(--accent); }

.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

/* 2. NAV-MENU */
.nav-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 5%;
    height: 85px;
    position: fixed;
    width: 100%;
    top: 0;
    background: var(--bg-glass);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
    transition: background 0.5s ease;
}

.nav-bar__logo {
    font-weight: 800;
    letter-spacing: 3px;
    font-size: 1.3rem;
    text-decoration: none;
    color: var(--text-main);
}

.nav-bar__logo span {
    color: var(--accent);
    font-weight: 300;
}

.nav-bar__links {
    display: flex;
    align-items: center;
}

@media (min-width: 769px) {
    .nav-bar__links {
        position: absolute;
        left: 50%;
        transform: translateX(-50%);
        white-space: nowrap; 
    }
}

.nav-bar__links a {
    text-decoration: none;
    color: var(--text-main);
    margin-left: 35px;
    font-weight: 600;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    position: relative;
    padding: 8px 0;
    transition: var(--transition);
}

.nav-bar__links a:not(.btn-nav)::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: 0;
    left: 50%;
    background: var(--accent);
    transition: var(--transition);
    transform: translateX(-50%);
}

.nav-bar__links a:not(.btn-nav):hover { color: var(--accent); }
.nav-bar__links a:not(.btn-nav):hover::after { width: 100%; }

.btn-nav {
    background: var(--text-main);
    color: var(--bg-body) !important;
    padding: 12px 25px !important;
    border-radius: 50px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    
    display: inline-flex; 
    align-items: center;
    justify-content: center;
    white-space: nowrap; 
    
    transition: var(--transition);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.btn-nav:hover {
    background: var(--accent) !important;
    color: white !important;
    transform: translateY(-2px);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 15px;
    z-index: 1100;
}

.theme-btn {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.3rem;
    color: var(--text-main);
    padding: 8px;
    border-radius: 50%;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-btn:hover {
    background: var(--bg-icon);
    color: var(--accent);
    transform: rotate(15deg);
}

.mobile-menu-icon {
    display: none;
    font-size: 1.8rem;
    cursor: pointer;
    color: var(--text-main);
    background: none;
    border: none;
    padding: 0;
}

/* 3. INTRO */
.intro {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
    overflow: hidden;
    color: #ffffff;
}

.intro__video {
    position: absolute;
    top: 50%;
    left: 50%;
    min-width: 100%;
    min-height: 100%;
    width: auto;
    height: auto;
    z-index: 1;
    transform: translate(-50%, -50%);
    object-fit: cover;
}

.intro__overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(15, 23, 42, 0.5) 0%, rgba(15, 23, 42, 0.85) 100%);
    z-index: 2;
}

.intro__content {
    max-width: 900px;
    position: relative;
    z-index: 3;
    padding: 0 20px;
}

.intro__tagline {
    display: inline-block;
    color: var(--accent-light);
    font-weight: 700;
    letter-spacing: 4px;
    font-size: 1.1rem; 
    text-transform: uppercase;
    margin-bottom: 20px;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.6);
}

.intro__title {
    font-size: clamp(3rem, 9vw, 6rem);
    line-height: 1.05;
    margin-bottom: 25px;
    font-weight: 800;
    text-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
}

.intro__description {
    font-size: 1.4rem;
    color: rgba(255, 255, 255, 0.95);
    margin-bottom: 40px;
    max-width: 700px;
    margin: 0 auto 40px;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.5);
}

/* 4. CARDS */
.section { padding: 120px 0; }
.section--alt { background: var(--bg-alt); }

.grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 30px;
}

.feature-card {
    background: var(--bg-card);
    padding: 60px 40px;
    border-radius: 24px;
    transition: var(--transition);
    border: 1px solid var(--border-color);
    text-align: center;
    flex: 1 1 320px;
    max-width: 400px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.02);
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-card);
    border-color: var(--accent);
}

.feature-card__icon-wrapper {
    width: 80px;
    height: 80px;
    background: var(--bg-icon);
    border-radius: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 30px;
    color: var(--accent);
    font-size: 2rem;
    transition: var(--transition);
}

.feature-card:hover .feature-card__icon-wrapper {
    background: var(--accent);
    color: white;
    transform: rotate(10deg) scale(1.05);
}

.feature-card h3 { color: var(--text-main); margin-bottom: 15px;}
.feature-card p { color: var(--text-muted); }

.gallery-wrapper {
    max-width: 900px;
    margin: 0 auto;
}

.main-image-container {
    position: relative;
    width: 100%;
    aspect-ratio: 16/9;
    border-radius: 24px;
    overflow: hidden;
    box-shadow: var(--shadow-card);
    margin-bottom: 20px;
}

.main-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: opacity 0.4s ease-in-out;
}

.main-image.fade-out {
    opacity: 0.5;
}

.gallery-arrow {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(15, 23, 42, 0.4);
    color: white;
    border: none;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    cursor: pointer;
    backdrop-filter: blur(5px);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    z-index: 10;
}

.gallery-arrow:hover {
    background: var(--accent);
}

.gallery-arrow.prev { left: 20px; }
.gallery-arrow.next { right: 20px; }

.thumbnails-row {
    display: flex;
    gap: 15px;
    justify-content: center;
}

.thumbnail {
    width: calc(25% - 12px); 
    aspect-ratio: 16/9;
    object-fit: cover;
    border-radius: 12px;
    cursor: pointer;
    opacity: 0.6;
    transition: var(--transition);
    border: 2px solid transparent;
}

.thumbnail:hover {
    opacity: 1;
    transform: translateY(-5px);
}

.thumbnail.active {
    opacity: 1;
    border-color: var(--accent);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

/* 5. RECENZE */
.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 60px;
    font-weight: 800;
    color: var(--text-main);
}

.testimonials {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.testimonial-item {
    background: var(--bg-card);
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.02);
    border-left: 4px solid var(--accent);
    transition: var(--transition);
}

.testimonial-item:hover { transform: translateX(5px); box-shadow: var(--shadow-card);}

.testimonial-quote {
    font-size: 1.1rem;
    margin-bottom: 20px;
    color: var(--text-main);
    font-style: italic;
}

.testimonial-author {
    font-weight: 700;
    color: var(--text-muted);
}

/* 6. PRODEJNÍ KARTA */
.price-card {
    background: var(--bg-card);
    padding: 80px 40px;
    border-radius: 40px;
    box-shadow: var(--shadow-card);
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
    border: 1px solid var(--border-color);
}

.price-card__title { margin: 15px 0; color: var(--text-main); }

.price-tag {
    font-size: 4rem;
    font-weight: 800;
    margin: 20px 0 30px;
    color: var(--text-main);
}

.specs-list {
    list-style: none;
    margin-bottom: 40px;
    text-align: left;
    display: inline-block;
}

.specs-list li {
    margin-bottom: 12px;
    color: var(--text-muted);
    font-size: 1.1rem;
}

.specs-list i {
    color: var(--accent);
    margin-right: 15px;
}

/* 7. TLAČÍTKA */
.btn-main {
    background: var(--accent);
    color: white;
    padding: 20px 45px;
    text-decoration: none;
    font-weight: 700;
    border-radius: 12px;
    display: inline-block;
    transition: var(--transition);
    text-transform: uppercase;
    letter-spacing: 2px;
    font-size: 0.9rem;
    border: none;
    cursor: pointer;
}

.btn-main:hover {
    background: var(--accent-hover);
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(94, 129, 172, 0.25);
}

@keyframes pulse-glow {
    0% { box-shadow: 0 0 0 0 rgba(94, 129, 172, 0.4); }
    70% { box-shadow: 0 0 0 20px rgba(94, 129, 172, 0); }
    100% { box-shadow: 0 0 0 0 rgba(94, 129, 172, 0); }
}

.btn-glow { animation: pulse-glow 2.5s infinite; }

/* 8. FOOTER */
footer {
    padding: 80px 0 40px;
    text-align: center;
    background: var(--bg-footer);
    border-top: 1px solid var(--border-color);
    transition: background 0.5s ease;
}

.social-icons { margin-bottom: 25px; }

.social-icons a {
    color: var(--text-muted);
    margin: 0 15px;
    font-size: 1.5rem;
    transition: var(--transition);
}

.social-icons a:hover{ 
    color: var(--accent); 
    transform: scale(1.1); 
    display: inline-block;
}

.stock-tag {
    color: #e63946;
    font-weight: 700;
    margin-top: 25px;
    font-size: 0.95rem;
}

/* 9. RESPONZIVITA */
@media (max-width: 768px) {
    .mobile-menu-icon { display: block; }

    .nav-bar__links {
        flex-direction: column;
        justify-content: center;
        position: fixed;
        top: 0;
        right: 0;
        width: 100%;
        height: 100vh;
        background: var(--bg-body);
        transform: translateX(100%);
        transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
        z-index: 1050;
    }
    
    .nav-bar__links.active { transform: translateX(0); }
    
    .btn-nav {
        white-space: normal;
        text-align: center;
    }

    .nav-bar__links a { margin: 20px 0; font-size: 1.5rem; }

    .theme-btn {
        margin-left: 0;
    }

    .intro__title { font-size: 3rem; }
    .section { padding: 80px 20px; }
    .price-tag { font-size: 3rem; }
    .price-card { padding: 50px 20px; }
    
    .main-image-container {
        aspect-ratio: 4/3;
    }
    
    .gallery-arrow {
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }
}