:root {
    --bg-color: #121212;
    --text-color: #f0f0f0;
    --accent-color: #555;
    --primary-color: #aaa;
}

html {
    scroll-behavior: smooth;
}

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

body {
    font-family: 'Lexend Deca', sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    background-color: var(--bg-color);
    overflow-x: hidden;
    position: relative;
}

::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-color);
}

::-webkit-scrollbar-thumb {
    background: #333;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-color);
}

.animovane-pozadi {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: linear-gradient(-45deg, #0a0a0f, #1a1a24, #121212, #0d1117);
    background-size: 400% 400%;
    z-index: -1;
    animation: stabilniGradient 15s ease infinite;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;
    transform: translateZ(0);
}

@keyframes stabilniGradient {
    0% {
        background-position: 0% 50%;
    }

    50% {
        background-position: 100% 50%;
    }

    100% {
        background-position: 0% 50%;
    }
}

.profilova-fotka {
    width: 160px;
    height: 160px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.5);
    margin-bottom: 25px;
    transition: transform 0.4s ease, border-color 0.4s ease;
}

.profilova-fotka:hover {
    transform: scale(1.02);
    border-color: #888;
}

.linkedin-odkaz {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-top: 15px;
    text-decoration: none;
    transition: transform 0.3s ease;
}

.linkedin-odkaz:hover {
    transform: translateY(-3px);
}

.linkedin-logo {
    width: 32px;
    height: 32px;
    fill: #aaa;
    transition: fill 0.3s ease;
}

.linkedin-odkaz:hover .linkedin-logo {
    fill: #0077b5;
}

.hlavni-navigace {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(18, 18, 18, 0.85);
    backdrop-filter: blur(12px);
    z-index: 100;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    min-height: 65px;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0 25px;
}

.nav-odkazy {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
}

.nav-odkazy a {
    color: var(--text-color);
    text-decoration: none;
    margin: 0 8px;
    font-size: 0.8rem; 
    text-transform: uppercase;
    letter-spacing: 1px; 
    transition: color 0.3s ease, border-bottom 0.3s ease;
    border-bottom: 2px solid transparent;
    padding-bottom: 5px;
}

.nav-odkazy a:hover,
.nav-odkazy a.aktivni {
    color: var(--primary-color);
    border-bottom: 2px solid var(--primary-color);
}

.lang-btn {
    position: absolute;
    right: 25px;
    margin: 0;
    background: transparent;
    color: var(--text-color);
    border: 1px solid var(--text-color);
    padding: 4px 10px;
    font-size: 0.85rem;
    cursor: pointer;
    border-radius: 4px;
    text-transform: uppercase;
    transition: all 0.3s ease;
    transform: translateY(-3px);
}

.lang-btn:hover {
    background: var(--text-color);
    color: var(--bg-color);
}

.hamburger {
    display: none;
    cursor: pointer;
    position: absolute;
    right: 25px;
    top: 50%;
    transform: translateY(-50%);
    z-index: 101;
}

.hamburger .bar {
    display: block;
    width: 25px;
    height: 2px;
    margin: 5px auto;
    background-color: var(--text-color);
    transition: all 0.3s ease-in-out;
}

header {
    text-align: center;
    padding: 150px 20px 60px;
    max-width: 800px;
    margin: 0 auto;
}

header h1 {
    font-size: 3.5rem;
    font-weight: 400;
    letter-spacing: 1px;
    margin-bottom: 10px;
    transition: font-family 0.5s ease;
}

header p {
    font-size: 1.2rem;
    color: #aaa;
}

.o-mne-sekce {
    max-width: 1400px;
    margin: 0 auto 80px;
    padding: 40px 30px;
    text-align: center;
    background-color: rgba(30, 30, 30, 0.4);
    border-radius: 8px;
    border: 1px solid rgba(255, 255, 255, 0.05);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(4px);
}

.o-mne-sekce h2 {
    margin-bottom: 20px;
    font-weight: 300;
    font-size: 2.2rem;
    color: var(--text-color);
    letter-spacing: 1px;
}

.o-mne-sekce p {
    color: #ccc;
    font-size: 1.15rem;
    line-height: 1.8;
    margin-bottom: 15px;
}

.kategorie-nadpis {
    text-align: center;
    font-weight: 300;
    font-size: 2.2rem;
    margin: 60px 0 30px;
    color: var(--text-color);
    letter-spacing: 1px;
}

.gallery-container {
    max-width: 1400px;
    margin: 0 auto 40px;
    padding: 0 20px;
    column-count: 3;
    column-gap: 20px;
}

.gallery-item {
    break-inside: avoid;
    margin-bottom: 20px;
    border-radius: 8px;
    overflow: hidden;
    cursor: pointer;
    position: relative;
    background-color: rgba(30, 30, 30, 0.6);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.gallery-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 35px rgba(0, 0, 0, 0.5);
}

.gallery-item img,
.gallery-item video {
    width: 100%;
    height: auto;
    display: block;
}

.dvoji-video-kontejner {
    column-span: all;
    display: flex;
    gap: 20px;
    margin-bottom: 20px;
    align-items: flex-start;
}

.rovnocenne-video {
    flex: 1;
    margin-bottom: 0;
}

.rovnocenne-video video {
    width: 100%;
    height: auto;
    border-radius: 8px;
    display: block;
}

.manual-sekce {
    max-width: 700px;
    margin: 80px auto;
    padding: 0 20px;
    text-align: center;
}

.manual-sekce h2 {
    margin-bottom: 20px;
    font-weight: 300;
    font-size: 2rem;
}

.manual-sekce p {
    color: #aaa;
    margin-bottom: 30px;
    font-size: 1.1rem;
}

.manual-odkaz {
    display: inline-block;
    width: 100%;
    text-decoration: none;
}

.manual-nahled-kontejner {
    position: relative;
    width: 100%;
    border-radius: 8px;
    overflow: hidden;
    background-color: #1e1e1e;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    transition: transform 0.3s ease;
}

.manual-nahled-kontejner img {
    width: 100%;
    height: auto;
    display: block;
}

.manual-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.manual-overlay span {
    color: var(--text-color);
    border: 1px solid var(--text-color);
    padding: 12px 25px;
    border-radius: 4px;
    text-transform: uppercase;
    letter-spacing: 2px;
    font-size: 0.85rem;
    font-weight: bold;
}

.manual-odkaz:hover .manual-nahled-kontejner {
    transform: translateY(-5px);
}

.manual-odkaz:hover .manual-overlay {
    opacity: 1;
}

.contact-section {
    max-width: 600px;
    margin: 80px auto;
    padding: 0 20px;
    text-align: center;
}

.contact-section h2 {
    margin-bottom: 30px;
    font-weight: 300;
}

form {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

input,
textarea {
    width: 100%;
    padding: 15px;
    background-color: rgba(30, 30, 30, 0.7);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-color);
    border-radius: 4px;
    font-family: inherit;
    transition: border-color 0.3s ease, background-color 0.3s ease, box-shadow 0.3s ease;
}

input:focus,
textarea:focus {
    outline: none;
    border-color: #888;
    background-color: rgba(40, 40, 40, 0.9);
    box-shadow: 0 0 12px rgba(136, 136, 136, 0.25);
}

textarea {
    resize: vertical;
    min-height: 150px;
}

button {
    padding: 15px;
    background-color: transparent;
    color: var(--text-color);
    border: 1px solid var(--text-color);
    border-radius: 4px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 1px;
}

button:hover {
    background-color: var(--text-color);
    color: var(--bg-color);
}

.formular-zprava {
    display: none;
    padding: 15px;
    background-color: rgba(76, 175, 80, 0.15);
    border: 1px solid #4CAF50;
    color: #4CAF50;
    border-radius: 4px;
    margin-top: 15px;
    font-weight: 300;
    transition: opacity 0.3s ease;
}

.formular-zprava.zobrazit {
    display: block;
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

footer {
    text-align: center;
    padding: 40px 20px;
    color: #777;
    font-size: 0.9rem;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.lightbox {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.95);
    z-index: 1000;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.lightbox.active {
    display: flex;
}

.lightbox-content {
    max-width: 90%;
    max-height: 90vh;
    border-radius: 4px;
}

.close-btn {
    position: absolute;
    top: 20px;
    right: 30px;
    color: white;
    font-size: 40px;
    cursor: pointer;
    font-weight: 300;
}


.timeline-sekce {
    max-width: 900px;
    margin: 0 auto 80px;
    padding: 0 20px;
}

.timeline-container {
    position: relative;
    padding-left: 40px;
}

/* Vertikální linie */
.timeline-container::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 2px;
    background: rgba(255, 255, 255, 0.1);
}

.timeline-item {
    position: relative;
    margin-bottom: 40px;
}

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


.timeline-dot {
    position: absolute;
    left: -45px;
    top: 5px;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background-color: var(--primary-color);
    box-shadow: 0 0 10px rgba(170, 170, 170, 0.5);
}


.timeline-content {
    background-color: rgba(30, 30, 30, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    padding: 25px;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(4px);
    transition: transform 0.3s ease, border-color 0.3s ease;
}

.timeline-content:hover {
    transform: translateX(8px);
    border-color: #888;
}

.timeline-date {
    color: #aaa;
    font-size: 0.9rem;
    margin-bottom: 8px;
    display: inline-block;
    letter-spacing: 1px;
}

.timeline-content h3 {
    font-size: 1.5rem;
    font-weight: 400;
    margin-bottom: 5px;
    color: var(--text-color);
}

.timeline-content h4 {
    font-size: 1.1rem;
    color: #888;
    font-weight: 300;
    margin-bottom: 12px;
}

.timeline-content p {
    color: #ccc;
    font-size: 1.05rem;
    line-height: 1.6;
}


#back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 45px;
    height: 45px;
    background-color: rgba(30, 30, 30, 0.7);
    color: var(--text-color);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease, transform 0.3s ease, background-color 0.3s ease;
    z-index: 999;
    backdrop-filter: blur(5px);
}

#back-to-top.zobrazit {
    opacity: 1;
    visibility: visible;
}

#back-to-top:hover {
    background-color: var(--text-color);
    color: var(--bg-color);
    transform: translateY(-5px);
}

#back-to-top svg {
    width: 22px;
    height: 22px;
}


.certifikaty-sekce {
    max-width: 1200px;
    margin: 0 auto 80px;
    padding: 0 20px;
}

.certifikaty-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    margin-top: 40px;
}

.cert-item {
    background-color: rgba(30, 30, 30, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 8px;
    padding: 25px;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(4px);
    transition: transform 0.3s ease, border-color 0.3s ease;
    text-align: center;
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: 120px;
}

.cert-item:hover {
    transform: translateY(-5px);
    border-color: #888;
}

.cert-item h3 {
    font-size: 1.15rem;
    font-weight: 400;
    color: var(--text-color);
    margin-bottom: 8px;
    line-height: 1.4;
}

.cert-item p {
    color: #aaa;
    font-size: 0.85rem;
    letter-spacing: 1.5px;
    text-transform: uppercase;
}

@media (max-width: 600px) {
    #back-to-top {
        bottom: 20px;
        right: 20px;
        width: 40px;
        height: 40px;
    }
}


@media (max-width: 600px) {
    .timeline-container {
        padding-left: 25px;
    }

    .timeline-dot {
        left: -30px;
        width: 10px;
        height: 10px;
    }

    .timeline-content {
        padding: 20px 15px;
    }
}

@media (prefers-reduced-motion: reduce) {

    body,
    .animovane-pozadi {
        animation: none;
    }

    html {
        scroll-behavior: auto;
    }

    .profilova-fotka,
    .gallery-item,
    .linkedin-odkaz,
    .manual-nahled-kontejner,
    .nav-odkazy a {
        transition: none;
    }

    .gallery-item:hover,
    .manual-odkaz:hover .manual-nahled-kontejner {
        transform: none;
    }
}

@media (max-width: 1100px) {
    .hamburger {
        display: block;
    }

    .nav-odkazy {
        position: fixed;
        top: 65px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 65px);
        background-color: rgba(18, 18, 18, 0.98);
        backdrop-filter: blur(15px);
        flex-direction: column;
        justify-content: flex-start;
        padding-top: 40px;
        transition: left 0.4s ease;
        z-index: 99;
        flex-wrap: nowrap;
        overflow-y: auto;
    }

    .nav-odkazy.active {
        left: 0;
    }

    .nav-odkazy a {
        margin: 15px 0;
        font-size: 1.2rem;
    }

    .hamburger.active .bar:nth-child(1) {
        transform: translateY(7px) rotate(45deg);
    }

    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-7px) rotate(-45deg);
    }

    .lang-btn {
        position: absolute;
        top: 50%;
        right: 75px;
        transform: translateY(-50%);
    }
}

@media (max-width: 900px) {
    .gallery-container {
        column-count: 2;
    }
}

@media (max-width: 600px) {
    .gallery-container {
        column-count: 1;
    }

    header h1 {
        font-size: 2.5rem;
    }

    .o-mne-sekce {
        padding: 30px 15px;
    }
}