:root {
    --holo-blue: #00f2ff;
    --holo-glow: rgba(0, 242, 255, 0.4);
    --stone: #0a0a0a;
}

body {
    background-color: var(--stone);
    background-image: url('https://www.transparenttextures.com/patterns/dark-matter.png');
    color: var(--holo-blue);
    font-family: 'Courier New', Courier, monospace;
    margin: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
}

/* LEFT SIDE BANNER */
.side-nav {
    position: fixed;
    left: -210px;
    top: 0;
    width: 250px;
    height: 100%;
    background: rgba(0, 242, 255, 0.05);
    backdrop-filter: blur(8px);
    border-right: 2px solid var(--holo-blue);
    transition: 0.4s ease;
    z-index: 100;
    display: flex;
    flex-direction: column;
    padding-top: 50px;
}

.side-nav:hover {
    left: 0;
    background: rgba(0, 15, 20, 0.95);
}

.nav-item {
    padding: 20px;
    color: var(--holo-blue);
    text-decoration: none;
    text-transform: uppercase;
    font-size: 0.9rem;
    border-bottom: 1px solid rgba(0, 242, 255, 0.1);
}

.nav-item:hover {
    background: var(--holo-blue);
    color: #000;
}

.nav-label {
    position: absolute;
    right: -35px;
    top: 50%;
    transform: rotate(90deg);
    letter-spacing: 5px;
}

header {
    text-align: center;
    padding: 80px 20px 40px;
}

.container {
    max-width: 800px;
    padding: 20px;
}

.artifact-card {
    border: 1px solid var(--holo-blue);
    padding: 20px;
    box-shadow: 0 0 20px var(--holo-glow);
}

.artifact-img {
    width: 100%;
    filter: sepia(100%) hue-rotate(150deg) brightness(1.2);
}

.flicker {
    animation: flicker 3s infinite;
}

@keyframes flicker {
    0% { opacity: 1; }
    50% { opacity: 0.8; }
    52% { opacity: 1; }
    100% { opacity: 1; }
}

#start-btn {
    background: transparent;
    color: var(--holo-blue);
    border: 1px solid var(--holo-blue);
    padding: 10px 20px;
    cursor: pointer;
    margin-top: 20px;
}

label {
    display: block;
    margin-bottom: 10px;
    font-size: 0.8rem;
    letter-spacing: 1px;
}