/* In-game UI elements */
#ui-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.5s ease-in-out, visibility 0s 0.5s;
}

#score, #combo {
    padding: 20px;
    font-size: 2em;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.7);
    display: none; /* Hide HUD elements by default */
}

#core-status {
    position: absolute;
    bottom: 20px;
    text-align: center;
    width: 100%;
    font-size: 1.5em;
    display: none; /* Hide HUD elements by default */
    text-shadow: 2px 2px 4px rgba(0,0,0,0.7);
}

#level-text {
    display: none; 
    font-size: 3em; 
    text-align: center; 
    position: absolute; 
    top: 40%; 
    left: 50%; 
    transform: translate(-50%, -50%);
}

#level-text.flash {
    animation: flash 0.5s 3;
}

/* Debug info */
#debug-info {
    position: absolute;
    top: 10px;
    left: 10px;
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 10px;
    border-radius: 5px;
    font-family: monospace;
    font-size: 12px;
    z-index: 150;
    display: none;
}

/* Mobile pause button */
#mobile-pause-button {
    position: absolute;
    bottom: 20px;
    left: 20px;
    background-color: rgba(20, 20, 40, 0.8);
    border: 2px solid #4a4a8a;
    border-radius: 15px;
    width: 50px;
    height: 50px;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    z-index: 160;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0s 0.3s;
    backdrop-filter: blur(5px);
}

#mobile-pause-button:hover {
    background-color: rgba(40, 40, 60, 0.9);
    border-color: #6a6aff;
}

#pause-icon {
    width: 20px;
    height: 20px;
    position: relative;
}

#pause-icon::before, 
#pause-icon::after {
    content: '';
    position: absolute;
    background-color: #c58aff;
    width: 4px;
    height: 16px;
    border-radius: 2px;
}

#pause-icon::before {
    left: 4px;
}

#pause-icon::after {
    right: 4px;
}

/* Virtual joystick */
#joystick-container {
    position: absolute;
    bottom: 80px;
    left: 30px;
    width: 150px;
    height: 150px;
    z-index: 150;
    opacity: 0.5;
    display: none; /* Hidden by default */
}

#joystick-base, #joystick-handle { 
    border-radius: 50%; 
}

#joystick-base { 
    position: relative; 
    width: 100%; 
    height: 100%; 
    background: rgba(80, 80, 120, 0.4); 
    border: 2px solid rgba(150, 150, 200, 0.3); 
}

#joystick-handle { 
    position: absolute; 
    top: 50%; 
    left: 50%; 
    width: 60px; 
    height: 60px; 
    background: rgba(150, 150, 200, 0.6); 
    transform: translate(-50%, -50%); 
    border: 2px solid rgba(200, 200, 255, 0.5);
}