:root {
    --bg-color: #ffffff;
    --fg-color: #24292f;
    --border-color: #d0d7de;
    --muted-color: #57606a;
    --panel-bg: #f6f8fa;
    --button-bg: #f6f8fa;
    --button-hover-bg: #f3f4f6;
    --button-border: #1b1f2426;
    --accent-color: #0969da;
    --focus-ring-color: #0969da80;
    --danger-color: #d73a49;
    --level-0-bg: #ebedf0;
    --level-1-bg: #9be9a8;
    --level-2-bg: #40c463;
    --level-3-bg: #30a14e;
    --level-4-bg: #216e39;
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
}

body.dark-mode {
    --bg-color: #0d1117;
    --fg-color: #c9d1d9;
    --border-color: #30363d;
    --muted-color: #8b949e;
    --panel-bg: #0d1117;
    --button-bg: #21262d;
    --button-hover-bg: #30363d;
    --button-border: #30363d;
    --accent-color: #58a6ff;
    --focus-ring-color: #58a6ff80;
    --danger-color: #f85149;
    --level-0-bg: #1C222C;
    --level-1-bg: #0e4429;
    --level-2-bg: #006d32;
    --level-3-bg: #26a641;
    --level-4-bg: #39d353;
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--fg-color);
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 16px;
    border-bottom: 1px solid var(--border-color);
    flex-shrink: 0;
}
header h1 { font-size: 1.2rem; }
.header-left, .header-right { display: flex; align-items: center; gap: 16px; }

main {
    display: grid;
    grid-template-columns: 280px 1fr 280px;
    gap: 16px;
    padding: 16px;
    flex-grow: 1;
    overflow: hidden;
}

aside {
    background-color: var(--panel-bg);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 12px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 16px;
}
.panel-section h3 {
    font-size: 0.9rem;
    margin-bottom: 8px;
    color: var(--muted-color);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

#main-content {
    display: flex;
    flex-direction: column;
    overflow: auto;
    gap: 24px; /* Default space between layers */
    padding-bottom: 50px;
}

/* Reduces gap between layers when Game Mode is active and seamless */
#main-content.game-seamless {
    gap: 4px; /* Should match the gap size used in JS drawing */
}

/* --- Styles for individual drawing areas (layers) --- */
.heatmap-instance {
    position: relative;
    border: 2px solid transparent;
    border-radius: 8px;
    padding: 10px;
    background-color: var(--panel-bg);
    cursor: pointer;
}

.heatmap-instance.active-layer {
    border-color: var(--accent-color);
}

.heatmap-container {
    position: relative;
    padding-left: 30px; /* Space for day labels */
    padding-top: 30px; /* Space for month labels */
    overflow-x: auto;
    width: 100%;
}

.close-layer-btn {
    position: absolute;
    top: -10px;
    right: -10px;
    width: 24px;
    height: 24px;
    padding: 0;
    border-radius: 50%;
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    color: var(--muted-color);
    font-size: 1.2rem;
    line-height: 1;
    font-weight: bold;
    z-index: 10;
    cursor: pointer;
}
.close-layer-btn:hover {
    background-color: var(--danger-color);
    color: white;
    border-color: var(--danger-color);
}

.heatmap-canvas { 
    cursor: crosshair;
    touch-action: none;
}

.heatmap-labels-left {
    position: absolute;
    left: 0;
    top: 30px;
    display: flex;
    flex-direction: column;
    gap: 4px; 
    color: var(--fg-color);
    font-size: 0.75rem;
}

.heatmap-labels-left span {
    height: 10px; 
}

.heatmap-labels-top {
    position: absolute;
    top: 12px;
    left: 30px;
    display: flex;
    color: var(--fg-color);
    font-size: 0.75rem;
}

.heatmap-month-label { position: absolute; }


/* --- UI Components --- */
button, select {
    background-color: var(--button-bg);
    color: var(--fg-color);
    border: 1px solid var(--button-border);
    border-radius: 6px;
    padding: 6px 12px;
    font-size: 0.875rem;
    cursor: pointer;
    transition: background-color 0.1s;
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

select option:disabled {
    color: var(--muted-color);
}

button:hover, select:hover { background-color: var(--button-hover-bg); }
button:focus, select:focus, input:focus {
    outline: none;
    box-shadow: 0 0 0 3px var(--focus-ring-color);
}
input[type="number"], input[type="color"] {
    background-color: var(--bg-color);
    color: var(--fg-color);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 5px;
    width: 60px;
}
input[type="range"] { vertical-align: middle; }
input[type="color"] { padding: 2px; width: 30px; height: 30px; border: 1px solid var(--border-color); vertical-align: middle; }
label { display: inline-flex; align-items: center; gap: 4px; font-size: 0.875rem; }

.toolbar { display: flex; gap: 4px; }
.tool-btn { padding: 6px; width: 36px; height: 36px; }
.tool-btn svg { width: 20px; height: 20px; fill: currentColor; }
.tool-btn[aria-pressed="true"] { background-color: var(--accent-color); color: white; }

.brush-mode-toggle { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; }

.level-selector { display: flex; gap: 4px; }
.level-btn { width: 30px; height: 30px; padding: 0; font-weight: bold; }
.level-btn[data-level="0"] { background-color: var(--level-0-bg); color: var(--fg-color); border: 1px solid var(--border-color);}
.level-btn[data-level="1"] { background-color: var(--level-1-bg); }
.level-btn[data-level="2"] { background-color: var(--level-2-bg); }
.level-btn[data-level="3"] { background-color: var(--level-3-bg); }
.level-btn[data-level="4"] { background-color: var(--level-4-bg); }

.palette-editor, .thresholds, .io-buttons, .frame-actions, .image-legend-actions, .zoom-controls, .layer-actions, .system-actions { 
    display: flex; 
    flex-wrap: wrap; 
    gap: 8px; 
}

.palette-actions {
    display: flex;
    gap: 8px;
    margin-top: 8px;
    align-items: center;
}
.palette-actions select {
    flex-grow: 1;
}

.image-legend-actions {
    flex-direction: column;
    align-items: stretch;
}

.system-actions #undo-btn,
.system-actions #redo-btn {
    flex-grow: 1; 
}

.system-actions #reset-all-settings {
    width: 100%; 
}

/* --- Timeline --- */
#frames-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
    max-height: 200px;
    overflow-y: auto;
    border: 1px solid var(--border-color);
    padding: 8px;
    border-radius: 6px;
}
.frame-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 4px;
    border-radius: 4px;
    cursor: grab;
    border: 2px solid transparent;
}
.frame-item.selected {
    border-color: var(--accent-color);
    background-color: color-mix(in srgb, var(--accent-color) 15%, transparent);
}
.frame-item:active { cursor: grabbing; }
.frame-item canvas { border: 1px solid var(--border-color); }
.frame-index { font-size: 0.8rem; color: var(--muted-color); width: 20px; }

.timeline-controls { 
    display: flex; 
    align-items: center; 
    gap: 12px; 
    flex-wrap: wrap;
}
.timeline-controls #anim-play { width: 36px; height: 36px; padding: 6px; }
.timeline-controls #anim-play svg { width: 100%; height: 100%; fill: currentColor; }
#anim-fps-display {
    font-size: 0.875rem;
    color: var(--muted-color);
    width: 2em;
    text-align: right;
    font-variant-numeric: tabular-nums;
}

.frame-move-controls {
    display: flex;
    gap: 12px;
    margin-top: 8px;
    align-items: center;
    flex-wrap: wrap;
}
.frame-move-buttons {
    display: flex;
    gap: 4px;
}
.frame-move-buttons button {
    width: 36px;
    height: 36px;
    padding: 0;
    font-size: 1.2rem;
}
.frame-shift-options {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.frame-randomize-action {
    margin-top: 12px;
    display: flex;
}
.frame-randomize-action button {
    flex-grow: 1;
}

.export-options { margin-top: 8px; }

.export-controls {
    display: flex;
    gap: 8px;
    align-items: center;
}
.export-controls select {
    flex-grow: 1;
}

/* --- Game HUD --- */
#game-hud {
    border: 1px solid var(--border-color);
    border-radius: 6px;
    margin-top: 16px;
    padding: 12px;
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
}
.game-hud-item { font-weight: bold; }
.game-controls, .game-options { display: flex; align-items: center; gap: 12px; }

/* --- Modal Styles --- */
#modal-backdrop {
    position: fixed;
    top: 0; left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 100;
}

#layer-data-modal {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 90%;
    max-width: 600px;
    max-height: 80vh;
    background-color: var(--panel-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 16px;
    z-index: 101;
    display: flex;
    flex-direction: column;
    gap: 12px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
}

#layer-data-modal p { font-size: 0.875rem; color: var(--muted-color); }

#layer-data-textarea {
    width: 100%;
    flex-grow: 1;
    resize: none;
    font-family: monospace;
    font-size: 0.8rem;
    background-color: var(--bg-color);
    color: var(--fg-color);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 8px;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 8px;
}

#help-modal {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 90%;
    max-width: 800px;
    max-height: 90vh;
    background-color: var(--panel-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 24px;
    z-index: 101;
    display: flex;
    flex-direction: column;
    gap: 16px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    overflow-y: auto;
}

#help-modal h2 {
    margin-bottom: 8px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 8px;
}

.help-section h3 {
    font-size: 1rem;
    color: var(--fg-color);
    text-transform: none;
    letter-spacing: normal;
    margin-bottom: 12px;
}
.help-section h4 {
    font-size: 0.9rem;
    color: var(--muted-color);
    margin-top: 12px;
    margin-bottom: 6px;
}

.help-section p, .help-section li {
    font-size: 0.9rem;
    line-height: 1.6;
}

.help-section ul, .help-section ol {
    padding-left: 20px;
    margin-bottom: 12px;
}

.help-section li {
    margin-bottom: 8px;
}
.help-section li ul {
    margin-top: 8px;
    margin-bottom: 0;
}
.help-section strong {
    background-color: color-mix(in srgb, var(--accent-color) 15%, transparent);
    padding: 2px 4px;
    border-radius: 4px;
    font-weight: bold;
}

.hidden { display: none !important; }
.dragging { opacity: 0.5; }

footer {
    padding: 8px 16px;
    border-top: 1px solid var(--border-color);
    text-align: center;
    font-size: 0.75rem;
    color: var(--muted-color);
    flex-shrink: 0;
}

/* --- Responsive --- */
@media (max-width: 1000px) {
    main {
        grid-template-columns: 240px 1fr;
        grid-template-rows: 1fr auto;
        grid-template-areas:
            "tools main"
            "timeline timeline";
    }
    #tools-panel { grid-area: tools; }
    #main-content { grid-area: main; }
    #timeline-panel { grid-area: timeline; flex-direction: row; flex-wrap: wrap; }
}

@media (max-width: 768px) {
    main {
        grid-template-columns: 1fr;
        grid-template-rows: auto auto auto;
        grid-template-areas:
            "main"
            "tools"
            "timeline";
    }
    aside { overflow-y: visible; }
    #timeline-panel, #tools-panel {
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: space-around;
    }
}