:root {
    --bg-primary: #F9F6F0; /* Alabaster Beige */
    --text-primary: #0A0A0A; /* Obsidian Black */
    --accent-gold: #C5A059; /* Metallic Gold */
    --font-heading: 'Cinzel', serif;
    --font-body: 'Inter', sans-serif;
}

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

body, html {
    width: 100%;
    height: 100%;
    overflow: hidden;
    background-color: var(--bg-primary);
    font-family: var(--font-body);
    color: var(--text-primary);
}

.viewer-container {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
}

/* Header UI */
.viewer-header {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    padding: 20px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 10;
    background: linear-gradient(to bottom, rgba(249, 246, 240, 0.9), transparent);
}

.back-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: opacity 0.3s;
}

.back-btn:hover {
    opacity: 0.7;
}

.brand {
    font-family: var(--font-heading);
    font-size: 20px;
    font-weight: 800;
    letter-spacing: 2px;
}
.brand span {
    color: var(--accent-gold);
    font-weight: 400;
}

/* Model Info Overlay */
.model-info {
    position: absolute;
    bottom: 120px;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    z-index: 10;
    pointer-events: none;
}

.model-info h1 {
    font-family: var(--font-heading);
    font-size: 32px;
    margin-bottom: 5px;
    text-shadow: 0 4px 20px rgba(249, 246, 240, 0.8);
}

.model-info p {
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 2px;
    opacity: 0.7;
}

/* model-viewer component */
model-viewer {
    width: 100%;
    height: 100%;
    background-color: var(--bg-primary);
    outline: none;
}

/* AR Button Customization */
.ar-btn {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--text-primary);
    color: var(--bg-primary);
    border: none;
    padding: 16px 32px;
    border-radius: 50px;
    font-family: var(--font-body);
    font-weight: 600;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
    transition: transform 0.2s, background 0.2s;
}

.ar-btn:active {
    transform: translateX(-50%) scale(0.95);
}

/* Loading Progress Bar */
.progress-bar {
    display: block;
    width: 33%;
    height: 4px;
    max-width: 200px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(0, 0, 0, 0.1);
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar.hide {
    visibility: hidden;
    transition: visibility 0.3s;
}

.update-bar {
    background-color: var(--accent-gold);
    width: 0%;
    height: 100%;
    transition: width 0.3s;
}

/* Error Message */
#error-message {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    background: rgba(255, 255, 255, 0.9);
    padding: 30px;
    border-radius: 12px;
    border: 1px solid rgba(0,0,0,0.1);
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    max-width: 80%;
}

#error-message.hidden {
    display: none;
}

#error-message i {
    color: #e74c3c;
    width: 40px;
    height: 40px;
    margin-bottom: 15px;
}

#error-message p {
    font-size: 14px;
    line-height: 1.5;
}

#missing-filename {
    font-weight: bold;
    color: var(--accent-gold);
}