:root {
    --bg-color: #000000;
    --text-color: #e0e0e0;
    --panel-bg: rgba(20, 20, 30, 0.8);
    --accent-color: #4facfe;
    --font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
}

body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    background-color: var(--bg-color);
    font-family: var(--font-family);
    color: var(--text-color);
}

#scene-container {
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 0;
}

#ui-layer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none; /* Let clicks pass through to canvas */
    display: grid;
    grid-template-areas: 
        "header header"
        "info   ."
        "controls controls";
    grid-template-rows: auto 1fr auto;
    grid-template-columns: 300px 1fr;
    padding: 20px;
    box-sizing: border-box;
    z-index: 1;
}

header {
    grid-area: header;
    text-shadow: 0 2px 4px rgba(0,0,0,0.8);
    pointer-events: auto;
}

h1 {
    margin: 0;
    font-size: 2rem;
    font-weight: 300;
    letter-spacing: 1px;
}

.subtitle {
    margin: 5px 0 0 0;
    opacity: 0.8;
    font-size: 0.9rem;
}

.info-panel {
    grid-area: info;
    margin-top: 20px;
    background: var(--panel-bg);
    backdrop-filter: blur(10px);
    padding: 20px;
    border-radius: 8px;
    border-left: 3px solid var(--accent-color);
    pointer-events: auto;
    align-self: start;
    max-width: 100%;
    transition: opacity 0.3s, transform 0.3s;
    max-height: 60vh;
    overflow-y: auto;
}

.description p {
    margin-bottom: 10px;
    line-height: 1.5;
    font-size: 0.9rem;
}

#planet-info.hidden {
    display: none;
}

#planet-info h2 {
    margin-top: 0;
    color: var(--accent-color);
}

#planet-info p {
    line-height: 1.6;
    font-size: 0.9rem;
    color: rgba(255,255,255,0.92);
}

.facts-grid {
    margin-top: 16px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 12px;
}

.fact-card {
    background: rgba(255,255,255,0.05);
    border: 1px solid rgba(255,255,255,0.08);
    border-radius: 10px;
    padding: 10px 12px;
    backdrop-filter: blur(6px);
}

.fact-label {
    font-size: 0.75rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: rgba(255,255,255,0.6);
}

.fact-value {
    margin-top: 4px;
    font-size: 0.95rem;
    font-weight: 600;
}

.controls {
    grid-area: controls;
    display: flex;
    gap: 20px;
    justify-content: center;
    align-items: center;
    background: var(--panel-bg);
    backdrop-filter: blur(10px);
    padding: 15px 30px;
    border-radius: 30px;
    pointer-events: auto;
    margin: 0 auto 20px auto;
    border: 1px solid rgba(255,255,255,0.1);
}

.control-group {
    display: flex;
    align-items: center;
    gap: 10px;
}

button {
    background: rgba(255,255,255,0.1);
    border: 1px solid rgba(255,255,255,0.2);
    color: white;
    padding: 8px 16px;
    border-radius: 4px;
    cursor: pointer;
    transition: background 0.2s;
}

button:hover {
    background: rgba(255,255,255,0.2);
}

input[type="range"] {
    cursor: pointer;
}

label {
    font-size: 0.9rem;
    opacity: 0.9;
}

/* Mobile Toggle */
.mobile-toggle {
    display: none;
    pointer-events: auto;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: var(--accent-color);
    color: #000;
    font-weight: bold;
    font-size: 1.2rem;
    border: none;
    position: absolute;
    top: 20px;
    right: 20px;
    z-index: 100;
    justify-content: center;
    align-items: center;
    padding: 0;
}

.lang-switcher {
    margin-bottom: 10px;
}

.lang-btn {
    padding: 2px 8px;
    font-size: 0.8rem;
    margin-right: 5px;
    border-radius: 4px;
    background: rgba(255,255,255,0.1);
    border: 1px solid rgba(255,255,255,0.2);
}
.lang-btn.active {
    background: var(--accent-color);
    color: #000;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    #ui-layer {
        grid-template-areas: 
            "header"
            "info"
            "controls";
        grid-template-columns: 1fr;
        padding: 15px;
    }
    
    .mobile-toggle {
        display: flex;
    }
    
    .info-panel {
        max-width: none;
        margin-top: 10px;
        position: absolute;
        bottom: 80px; /* Above controls */
        left: 15px;
        right: 15px;
        max-height: 50vh;
        z-index: 10;
        
        /* Hidden by default on mobile */
        opacity: 0;
        pointer-events: none;
        transform: translateY(20px);
    }

    .info-panel.open {
        opacity: 1;
        pointer-events: auto;
        transform: translateY(0);
    }

    .controls {
        flex-direction: column;
        width: 100%;
        border-radius: 12px;
        gap: 15px;
        position: absolute;
        bottom: 15px;
        left: 0;
        right: 0;
        margin: 0 15px;
        width: auto;
    }
    
    .control-group {
        width: 100%;
        justify-content: space-between;
    }
}

.back-to-home {
    position: fixed;
    top: 20px;
    right: 70px; /* Move left of toggle */
    padding: 8px 16px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 999px;
    color: var(--text-color);
    text-decoration: none;
    font-size: 0.9rem;
    backdrop-filter: blur(10px);
    transition: background 0.2s;
    z-index: 100;
}

.back-to-home:hover {
    background: rgba(255, 255, 255, 0.2);
}