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

html {
    height: 100%;
    overflow: hidden; /* Lock the html */
}

body {
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden; /* Body shouldn't scroll */
    display: flex;
    flex-direction: column;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: #333;
    background-image: url('cab.png');
    background-size: 100% auto;
    background-repeat: repeat-y;
    background-position: center top;
    background-attachment: fixed;
}

@font-face {
    font-family: "Graffiti";
    src:
        local("graffiti"),
        url("fonts/graffiti.otf")
}

@font-face {
    font-family: "Graffiti2";
    src:
        local("graffiti2"),
        url("fonts/graffiti2.otf")
}

/* Navigation Wrapper */
.nav-wrapper {
    background: none;
}

/* Collapsible Gap with Logo */
.nav-gap {
    height: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: transform 0.3s ease, opacity 0.3s ease;
    transform-origin: top;
    will-change: transform, opacity;
}

.nav-gap.collapsed {
    transform: translateY(-100%) scaleY(0);
    opacity: 0;
    pointer-events: none;
}

.logo {
    width: auto;
    height: 100%;
    object-fit: contain;
    padding: 0 2rem;
}

/* Navigation Buttons Container */
.nav-buttons {
    display: flex;
    width: 100%;
    column-gap: 5%;
    padding-left: 5%;
    padding-right: 5%;
    position: sticky;
    top: 0;
    z-index: 999;
    
    height: 100px;
    transition: transform 0.3s ease, opacity 0.3s ease;
    transform-origin: top;
    will-change: transform, opacity;
}

.nav-buttons.collapsed {
    transform: translateY(-100%) scaleY(0);
    opacity: 0;
    pointer-events: none;
}

.nav-btn {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    font-size: 2.0rem;
    color: rgb(255, 255, 255);
    background: linear-gradient(135deg, rgba(37, 37, 37, 0.644) 0%, rgb(123, 124, 124) 100%);
    border: none;
    cursor: pointer;
    transition: font-size 0.2s ease, background 0.2s ease; /* Faster, specific transitions */
    text-transform: uppercase;
    letter-spacing: 1px;
    text-decoration: none;
    text-align: center;
    font-family: 'Graffiti2', sans-serif;
    font-weight: lighter;
}

.nav-btn:hover {
    font-size: 2.3rem;
    font-weight: bolder;
    color: #3f3f3f;
}

.nav-btn:active,
.nav-btn.active {
    background: #e9ecef;
    border-bottom-color: #667eea;
    color: #667eea;
}

/* Individual Nav Button Styles */
/* Button 1 - Domov */

.nav-btn-1:hover {
    background: linear-gradient(135deg, rgba(247, 36, 36, 0.397) 0%, rgba(199, 13, 13, 1) 100%);
    /* Custom hover for Domov */
}

.nav-btn-2:hover {
    background: linear-gradient(135deg, rgba(52, 101, 238, 0.45) 0%, rgb(0, 165, 241) 100%);
}

.nav-btn-3:hover {
    background: linear-gradient(135deg, rgba(238, 255, 0, 0.45) 0%, rgba(251, 255, 0, 0.918) 100%);
}

.nav-btn-4:hover {
    background: linear-gradient(135deg, rgba(28, 241, 57, 0.45) 0%, rgb(0, 255, 34) 100%);
}

.nav-btn-5:hover {
    background: linear-gradient(135deg, rgba(52, 101, 238, 0.45) 0%, rgb(0, 165, 241) 100%);
}

.nav-btn-6:hover {
    background: linear-gradient(135deg, rgba(247, 36, 36, 0.397) 0%, rgba(199, 13, 13, 0.212) 100%);
}

/* Main Content */
/* Main Content - THIS is your scroll container */
.main-content {
    flex: 1;
    overflow-y: scroll;
    overflow-x: hidden;
    background: none;
    
    /* Scroll performance optimizations */
    transform: translateZ(0);
    -webkit-transform: translateZ(0);
    overscroll-behavior: none;
    scroll-behavior: auto;
    
    /* Force hardware acceleration */
    will-change: scroll-position;
}