:root {
    --bg-gradient: linear-gradient(135deg, #000000 0%, #1a1a2e 100%);
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.6);
    --accent: #39ff14; /* Neon Green */
    --piece-1x1: #ffff00; /* Neon Yellow */
    --piece-1x2: #00ffff; /* Neon Cyan */
    --piece-2x2: #ff0000; /* Neon Red */
    --cell-size: 70px;
    --gap: 10px;
}

@media (max-width: 400px) {
    :root {
        --cell-size: 18vw;
        --gap: 6px;
    }
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: 'Outfit', sans-serif;
    background: #000000;
    background-image: 
        radial-gradient(at 0% 0%, rgba(57, 255, 20, 0.1) 0px, transparent 50%),
        radial-gradient(at 100% 0%, rgba(255, 0, 0, 0.1) 0px, transparent 50%),
        radial-gradient(at 100% 100%, rgba(0, 255, 255, 0.1) 0px, transparent 50%),
        radial-gradient(at 0% 100%, rgba(255, 255, 0, 0.1) 0px, transparent 50%);
    color: var(--text-primary);
    height: 100vh;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
}

.app-container {
    width: 100%;
    max-width: 450px;
    height: 100vh;
    display: flex;
    flex-direction: column;
    padding: 20px;
    gap: 20px;
}

.glass {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    box-shadow: var(--glass-shadow);
}

header .header-content {
    padding: 12px 20px;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.header-main {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

h1 {
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: 1px;
    margin: 0;
}

.logo-group {
    display: flex;
    align-items: center;
    gap: 12px;
}

.header-logo {
    width: 32px;
    height: 32px;
    border-radius: 8px;
    object-fit: cover;
    box-shadow: 0 0 10px rgba(74, 222, 128, 0.3);
}

.accent {
    color: var(--accent);
}

.stats {
    display: flex;
    gap: 16px;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.label {
    font-size: 0.7rem;
    text-transform: uppercase;
    color: var(--text-secondary);
    font-weight: 600;
}

.value {
    font-size: 1.2rem;
    font-weight: 800;
}

.btn-icon-small {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid var(--glass-border);
    color: white;
    width: 54px;
    height: 54px;
    border-radius: 16px;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-icon-small:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

main {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
}

#game-board-container {
    padding: 16px;
    position: relative;
    border-radius: 24px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.board-grid {
    position: relative;
    width: calc(var(--cell-size) * 4 + var(--gap) * 3);
    height: calc(var(--cell-size) * 5 + var(--gap) * 4);
    background: rgba(0, 0, 0, 0.3);
    border-radius: 16px;
    /* Removed overflow: hidden to prevent piece clipping during transitions */
}

.exit-gate {
    position: absolute;
    bottom: 8px; /* Adjusted to align with the bottom of the grid */
    left: 50%;
    transform: translateX(-50%);
    width: calc(var(--cell-size) * 2 + var(--gap));
    height: 4px;
    background: var(--accent);
    box-shadow: 0 0 15px var(--accent);
    border-radius: 10px;
    z-index: 1;
}

.win-message {
    color: var(--accent);
    text-shadow: 0 0 20px rgba(74, 222, 128, 0.5);
    margin-bottom: 30px;
}

/* Pieces */
.piece {
    position: absolute;
    border-radius: 14px;
    cursor: grab;
    transition: transform 0.2s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.2s ease;
    display: flex;
    justify-content: center;
    align-items: center;
    user-select: none;
    touch-action: none;
    border: 2px solid rgba(255, 255, 255, 0.8);
    will-change: transform;
    
    /* Responsive positioning using variables */
    left: calc(var(--x) * (var(--cell-size) + var(--gap)));
    top: calc(var(--y) * (var(--cell-size) + var(--gap)));
}

.piece.no-transition {
    transition: none !important;
}

.piece:active {
    cursor: grabbing;
    transform: scale(0.98);
    box-shadow: inset 0 0 30px rgba(255, 255, 255, 0.2);
}

.piece-2x2 {
    width: calc(var(--cell-size) * 2 + var(--gap));
    height: calc(var(--cell-size) * 2 + var(--gap));
    background: var(--piece-2x2);
    box-shadow: 0 0 30px rgba(255, 0, 0, 0.8), inset 0 0 15px rgba(255, 255, 255, 0.5);
    z-index: 5;
}

.piece-2x2::after {
    content: '★';
    font-size: 2rem;
    color: rgba(255, 255, 255, 0.5);
}

.piece-1x2 {
    width: var(--cell-size);
    height: calc(var(--cell-size) * 2 + var(--gap));
    background: var(--piece-1x2);
    box-shadow: 0 0 20px rgba(0, 255, 255, 0.7), inset 0 0 10px rgba(255, 255, 255, 0.5);
}

.piece-2x1 {
    width: calc(var(--cell-size) * 2 + var(--gap));
    height: var(--cell-size);
    background: var(--piece-1x2);
    box-shadow: 0 0 20px rgba(0, 255, 255, 0.7), inset 0 0 10px rgba(255, 255, 255, 0.5);
}

.piece-1x1 {
    width: var(--cell-size);
    height: var(--cell-size);
    background: var(--piece-1x1);
    box-shadow: 0 0 20px rgba(255, 255, 0, 0.7), inset 0 0 10px rgba(255, 255, 255, 0.5);
}

footer {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 20px;
}

.btn-primary {
    background: var(--accent);
    color: #064e3b; /* Dark green text for contrast */
    border: none;
    padding: 12px 32px;
    border-radius: 16px;
    font-weight: 800;
    font-size: 1rem;
    cursor: pointer;
    transition: transform 0.2s, background 0.2s;
    box-shadow: 0 4px 15px rgba(74, 222, 128, 0.3);
}

.btn-primary:hover {
    background: #22c55e;
    transform: translateY(-2px);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    border: 1px solid var(--glass-border);
    padding: 10px 24px;
    border-radius: 12px;
    font-weight: 600;
    cursor: pointer;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
}

.selector-footer {
    padding-top: 10px;
    display: flex;
    justify-content: center;
}

.btn-icon {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: white;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-icon:hover {
    background: rgba(255, 255, 255, 0.2);
}

.level-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 8px;
}

.badge {
    background: rgba(255, 255, 255, 0.1);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.best {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-secondary);
}

/* Overlays */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    opacity: 1;
    transition: opacity 0.3s ease;
    padding: 20px;
}

.overlay.hidden {
    display: none;
    opacity: 0;
}

.overlay-content h2 {
    font-size: 1.5rem;
    color: var(--text-primary);
    text-align: center;
    margin-bottom: 5px;
    font-weight: 800;
    letter-spacing: 1px;
}

.overlay-content.wide {
    max-width: 90%;
    width: 420px;
    height: 80vh;
    display: flex;
    flex-direction: column;
    padding: 40px 24px 24px 24px; /* More padding at top for title */
}

.level-grid-container {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    margin: 15px 0;
    padding: 15px 20px 15px 15px; /* More padding on the right for scrollbar */
    border-radius: 16px;
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--glass-border);
}

.level-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
}

.level-item {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    color: white;
    padding: 12px 8px;
    border-radius: 12px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s;
    text-align: center;
}

.level-item:hover {
    background: var(--accent);
    transform: scale(1.05);
}

.level-item.completed {
    border-color: #22c55e;
    color: #22c55e;
}

/* Custom Scrollbar for level grid */
.level-grid-container::-webkit-scrollbar {
    width: 4px;
}

.level-grid-container::-webkit-scrollbar-track {
    background: transparent;
}

.level-grid-container::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 10px;
}

.level-grid-container::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
}