:root {
    --bg: #0d1117;
    --surface: #161b22;
    --surface-hover: #1c2128;
    --border: #30363d;
    --text: #e6edf3;
    --muted: #8b949e;
    --accent: #f0883e;
    --accent-glow: rgba(240, 136, 62, 0.25);
    --blue: #58a6ff;
    --green: #3fb950;
    --red: #f85149;
    --highlight-bg: rgba(240, 136, 62, 0.18);
    --shadow: 0 4px 16px rgba(0,0,0,0.4);
    
    /* Font settings */
    --font-main: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
}

/* Themes */
body.theme-light {
    --bg: #ffffff;
    --surface: #f6f8fa;
    --surface-hover: #eaeef2;
    --border: #d0d7de;
    --text: #24292f;
    --muted: #57606a;
    --blue: #0969da;
    --green: #1a7f37;
    --red: #cf222e;
    --highlight-bg: rgba(240, 136, 62, 0.12);
}

body.theme-dracula {
    --bg: #282a36;
    --surface: #44475a;
    --surface-hover: #6272a4;
    --border: #6272a4;
    --text: #f8f8f2;
    --muted: #bd93f9;
    --blue: #8be9fd;
    --green: #50fa7b;
    --red: #ff5555;
}

/* Scrollbar styling */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--muted); }

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

body {
    font-family: var(--font-main);
    background-color: var(--bg);
    color: var(--text);
    height: 100vh;
    overflow: hidden;
    user-select: none;
}

.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    width: 100vw;
    overflow: hidden;
}

/* Toolbar */
.toolbar {
    height: 48px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 16px;
    border-bottom: 1px solid var(--border);
    background-color: var(--surface);
    box-shadow: var(--shadow);
    z-index: 200;
    flex-shrink: 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
    font-size: 16px;
    color: var(--accent);
    letter-spacing: -0.3px;
    transition: color 0.2s ease;
}

.logo-icon {
    color: var(--accent);
    transition: color 0.2s ease;
}

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

.theme-toggles {
    display: flex;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 2px;
}

.theme-toggles .icon-btn {
    width: 26px;
    height: 26px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    cursor: pointer;
    font-size: 13px;
    transition: all 0.2s;
    background: none;
    border: none;
}

.theme-toggles .icon-btn.active {
    background: var(--border);
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.theme-toggles .icon-btn:hover:not(.active) {
    background: rgba(255,255,255,0.05);
}

/* Accent Color Picker */
.accent-picker {
    display: flex;
    align-items: center;
    gap: 6px;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 4px 8px;
}

.accent-dot {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    border: 2px solid transparent;
    cursor: pointer;
    transition: transform 0.15s, border-color 0.15s;
    outline: none;
}

.accent-dot:hover {
    transform: scale(1.25);
}

.accent-dot.active {
    border-color: var(--text);
    transform: scale(1.15);
    box-shadow: 0 0 8px var(--accent-glow);
}

select {
    background-color: var(--bg);
    color: var(--text);
    border: 1px solid var(--border);
    padding: 5px 10px;
    border-radius: 6px;
    font-family: inherit;
    font-size: 12px;
    outline: none;
    cursor: pointer;
    transition: border-color 0.15s;
}

select:hover {
    border-color: var(--muted);
}

.btn {
    background-color: var(--surface);
    color: var(--text);
    border: 1px solid var(--border);
    padding: 6px 14px;
    border-radius: 6px;
    font-size: 12px;
    cursor: pointer;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1), background-color 0.15s, box-shadow 0.2s;
}

.btn:hover {
    background-color: var(--border);
    transform: translateY(-2px) scale(1.03);
}

.btn:active {
    transform: translateY(0) scale(0.96);
}

.btn.primary {
    background-color: var(--accent);
    color: #fff;
    border-color: var(--accent);
    box-shadow: 0 3px 12px var(--accent-glow);
}

.btn.primary:hover {
    filter: brightness(1.1);
    box-shadow: 0 6px 16px var(--accent-glow);
}

.btn.primary:hover {
    filter: brightness(1.1);
}

/* Main Content Workspace Layout */
.main-content {
    display: flex;
    flex: 1;
    overflow: hidden;
    position: relative;
    width: 100%;
}

.workspace-wrapper {
    display: flex;
    flex-direction: column;
    flex: 1;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.workspace-top {
    display: flex;
    flex-direction: row;
    flex: 1;
    min-height: 120px;
    overflow: hidden;
    position: relative;
}

.left-panel {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-width: 0;
    overflow: hidden;
    background-color: var(--bg);
}

.right-panel {
    display: flex;
    flex-direction: column;
    width: 320px;
    min-width: 180px;
    flex-shrink: 0;
    background-color: var(--surface);
    border-left: 1px solid var(--border);
    overflow: hidden;
}

/* ── Multi-File Browser Tabs Bar ─────────────────────────────── */
.editor-tabs-bar {
    display: flex;
    align-items: center;
    background-color: var(--bg);
    border-bottom: 1px solid var(--border);
    height: 36px;
    min-height: 36px;
    padding: 0 4px;
    user-select: none;
    overflow-x: auto;
    flex-shrink: 0;
}

.editor-tabs-list {
    display: flex;
    align-items: center;
    gap: 2px;
    height: 100%;
}

.file-tab {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 0 12px;
    height: 30px;
    background: transparent;
    border: 1px solid transparent;
    border-radius: 6px 6px 0 0;
    color: var(--muted);
    font-family: var(--font-mono);
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    position: relative;
    transition: all 0.15s cubic-bezier(0.16, 1, 0.3, 1);
    animation: tab-slide-in 0.2s ease-out;
}

.file-tab:hover {
    color: var(--text);
    background-color: rgba(255,255,255,0.03);
}

.file-tab.active {
    color: var(--text);
    background-color: var(--surface);
    border-color: var(--border);
    border-bottom-color: var(--surface);
    font-weight: 600;
}

.file-tab.active::before {
    content: '';
    position: absolute;
    top: -1px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--accent);
    border-radius: 2px 2px 0 0;
}

.file-tab-icon {
    font-size: 13px;
}

.file-tab-name {
    max-width: 140px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    cursor: text;
}

.file-tab-rename-input {
    background: var(--bg);
    border: 1px solid var(--accent);
    color: var(--text);
    font-family: var(--font-mono);
    font-size: 12px;
    padding: 1px 4px;
    border-radius: 3px;
    outline: none;
    width: 90px;
}

.file-tab-close {
    background: none;
    border: none;
    color: var(--muted);
    font-size: 14px;
    line-height: 1;
    width: 18px;
    height: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 3px;
    cursor: pointer;
    opacity: 0.6;
    transition: all 0.15s;
}

.file-tab-close:hover {
    opacity: 1;
    color: var(--red);
    background: rgba(248, 81, 73, 0.15);
}

.file-tab-add {
    background: none;
    border: none;
    color: var(--muted);
    font-size: 16px;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    cursor: pointer;
    margin-left: 4px;
    transition: all 0.15s;
}

.file-tab-add:hover {
    color: var(--text);
    background: var(--surface-hover);
}

/* Panel Header */
.panel-header {
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 0.6px;
    color: var(--muted);
    padding: 8px 12px;
    border-bottom: 1px solid var(--border);
    background-color: var(--surface);
    font-weight: 600;
    display: flex;
    justify-content: space-between;
    align-items: center;
    user-select: none;
    height: 36px;
    min-height: 36px;
    flex-shrink: 0;
}

.panel-title {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--muted);
}

.panel-icon {
    fill: currentColor;
    opacity: 0.85;
}

.panel-badge {
    font-size: 10px;
    font-weight: 600;
    color: var(--muted);
    padding: 2px 6px;
    border-radius: 4px;
    background: rgba(255,255,255,0.04);
    border: 1px solid var(--border);
}

.panel-actions {
    display: flex;
    align-items: center;
    gap: 4px;
}

.panel-toggle-btn {
    background: none;
    border: none;
    color: var(--muted);
    cursor: pointer;
    width: 22px;
    height: 22px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    transition: all 0.15s;
}

.panel-toggle-btn:hover {
    color: var(--text);
    background: var(--border);
}

.icon-chevron {
    transition: transform 0.2s ease;
}

.section-collapsed .icon-chevron {
    transform: rotate(-90deg);
}

.section-collapsed .panel-content,
.section-collapsed textarea,
.section-collapsed #editor-container {
    display: none !important;
}

.section-collapsed {
    flex: 0 0 auto !important;
    height: auto !important;
}

.panel-section {
    display: flex;
    flex-direction: column;
    min-height: 0;
    position: relative;
}

.editor-section {
    flex: 1;
    min-height: 100px;
}

.stdin-section {
    height: 120px;
    min-height: 36px;
    flex-shrink: 0;
}

#editor-container {
    flex: 1;
    width: 100%;
    height: 100%;
}

#stdin-input {
    flex: 1;
    background-color: var(--bg);
    color: var(--text);
    border: none;
    padding: 10px 14px;
    font-family: var(--font-mono);
    font-size: 13px;
    line-height: 1.5;
    resize: none;
    outline: none;
    user-select: text;
}

/* Stack Section in Sidebar */
.stack-section {
    flex: 1;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

#call-stack-container {
    flex: 1;
    overflow-y: auto;
    padding: 0;
}

/* Bottom Docked Panel (VS Code Style) */
.bottom-dock {
    display: flex;
    flex-direction: column;
    height: 220px;
    min-height: 36px;
    max-height: 80%;
    background-color: var(--surface);
    border-top: 1px solid var(--border);
    overflow: hidden;
    flex-shrink: 0;
    position: relative;
}

.bottom-dock.maximized {
    height: calc(100% - 36px) !important;
}

.bottom-dock.minimized {
    height: 36px !important;
}

.bottom-dock.minimized .bottom-dock-body {
    display: none;
}

.bottom-dock-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: var(--bg);
    border-bottom: 1px solid var(--border);
    height: 36px;
    min-height: 36px;
    padding: 0 8px;
    user-select: none;
    flex-shrink: 0;
}

.dock-tabs {
    display: flex;
    align-items: center;
    gap: 2px;
    height: 100%;
}

.dock-tab {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 0 14px;
    height: 100%;
    background: transparent;
    border: none;
    border-bottom: 2px solid transparent;
    color: var(--muted);
    font-family: var(--font-main);
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.15s;
}

.dock-tab:hover {
    color: var(--text);
    background-color: rgba(255,255,255,0.03);
}

.dock-tab.active {
    color: var(--text);
    border-bottom-color: var(--accent);
    font-weight: 600;
    background-color: var(--surface);
}

.tab-icon {
    opacity: 0.8;
}

.dock-badge {
    font-size: 10px;
    font-weight: 700;
    padding: 1px 6px;
    border-radius: 10px;
    background: var(--border);
    color: var(--muted);
}

.dock-tab.active .dock-badge {
    background: var(--accent-glow);
    color: var(--accent);
}

.dock-actions {
    display: flex;
    align-items: center;
    gap: 4px;
}

.dock-action-btn {
    background: none;
    border: none;
    color: var(--muted);
    width: 26px;
    height: 26px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.15s;
}

.dock-action-btn:hover {
    color: var(--text);
    background-color: var(--surface-hover);
}

.bottom-dock-body {
    flex: 1;
    overflow: hidden;
    position: relative;
    background-color: var(--surface);
}

.tab-pane {
    display: none;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.tab-pane.active {
    display: flex;
    flex-direction: column;
}

/* Inner Tab Contents */
.output-content {
    padding: 12px 16px;
    font-family: var(--font-mono);
    font-size: 13px;
    line-height: 1.5;
    color: var(--green);
    white-space: pre-wrap;
    word-break: break-all;
    overflow-y: auto;
    flex: 1;
    user-select: text;
}

#heap-container {
    padding: 14px;
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    align-content: flex-start;
    overflow-y: auto;
    flex: 1;
}

.history-pane-content {
    display: flex;
    flex-direction: column;
    height: 100%;
    overflow: hidden;
}

.history-controls {
    padding: 8px 14px;
    display: flex;
    gap: 10px;
    align-items: center;
    border-bottom: 1px solid var(--border);
    background-color: var(--bg);
    flex-shrink: 0;
}

.history-label {
    font-size: 11px;
    color: var(--muted);
    text-transform: uppercase;
    font-weight: 600;
}

#history-var-select {
    flex: 1;
    max-width: 240px;
    padding: 4px 8px;
    font-size: 12px;
    background: var(--surface);
    border: 1px solid var(--border);
    color: var(--text);
    border-radius: 4px;
    outline: none;
}

#history-table-container {
    flex: 1;
    overflow-y: auto;
}

/* Prevent inner elements from stealing pointer events during active drag */
body.is-resizing iframe,
body.is-resizing textarea,
body.is-resizing #editor-container,
body.is-resizing .monaco-editor,
body.is-resizing .panel-content {
    pointer-events: none !important;
    user-select: none !important;
}

/* ── Smooth Resizers (Pointer Events) ───────────────────── */
.resize-divider-h {
    width: 5px;
    background: var(--surface);
    border-left: 1px solid var(--border);
    border-right: 1px solid var(--border);
    cursor: col-resize;
    flex-shrink: 0;
    position: relative;
    z-index: 100;
    user-select: none;
    touch-action: none;
    transition: background 0.15s, border-color 0.15s;
}

.resize-divider-h:hover,
.resize-divider-h.dragging {
    background: var(--accent);
    border-color: var(--accent);
    box-shadow: 0 0 10px var(--accent-glow);
}

.resize-divider-v {
    height: 5px;
    background: var(--surface);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    cursor: row-resize;
    flex-shrink: 0;
    position: relative;
    z-index: 100;
    user-select: none;
    touch-action: none;
    transition: background 0.15s, border-color 0.15s;
}

.resize-divider-v:hover,
.resize-divider-v.dragging {
    background: var(--accent);
    border-color: var(--accent);
    box-shadow: 0 0 10px var(--accent-glow);
}

/* Empty State Styling */
.empty-state {
    color: var(--muted);
    font-size: 13px;
    text-align: center;
    padding: 24px;
    user-select: none;
}

/* Stack Frames Card Styling */
.stack-frame {
    border-bottom: 1px solid var(--border);
    animation: slide-in 150ms ease-out;
}

.frame-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 14px;
    background-color: rgba(255,255,255,0.02);
    border-bottom: 1px solid var(--border);
    font-family: var(--font-mono);
    font-size: 12px;
    cursor: pointer;
    user-select: none;
    transition: background-color 0.1s;
}

.frame-header:hover {
    background-color: rgba(255,255,255,0.06);
}

.frame-func { color: var(--blue); font-weight: 600; }
.frame-line { color: var(--muted); font-size: 11px; }

/* Variables inside Stack Frames */
.var-row {
    display: flex;
    align-items: baseline;
    padding: 6px 14px;
    border-bottom: 1px solid rgba(48, 54, 61, 0.4);
    font-family: var(--font-mono);
    font-size: 12.5px;
    gap: 10px;
    user-select: text;
    transition: background-color 0.15s;
}

.var-row:last-child { border-bottom: none; }
.var-row:hover { background-color: rgba(255,255,255,0.02); }

.var-name {
    color: var(--muted);
    width: 95px;
    flex-shrink: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    display: flex;
    align-items: center;
    gap: 4px;
    font-weight: 500;
}

.var-name.foldable {
    cursor: pointer;
    user-select: none;
}

.var-name.foldable:hover {
    color: var(--blue);
}

.var-val {
    color: var(--text);
    flex: 1;
    word-break: break-all;
    white-space: pre-wrap;
}

.var-row.var-uninit .var-name { color: var(--border); }
.var-row.var-uninit .var-val {
    color: var(--muted);
    font-style: italic;
    font-size: 12px;
}

.var-row.var-changed { animation: flash 400ms ease-out; }
.var-row.var-changed .var-val { color: var(--accent); font-weight: 600; }
.var-row.var-new-val .var-val { color: var(--green); font-weight: 600; }

/* Scopes Container */
.var-scope {
    margin: 8px 12px;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border);
    border-radius: 6px;
    overflow: hidden;
}

.var-scope.active-scope {
    border-color: var(--accent-glow);
    background: rgba(240, 136, 62, 0.03);
}

.scope-header {
    background: rgba(255, 255, 255, 0.03);
    padding: 6px 12px;
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--muted);
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.active-scope .scope-header {
    color: var(--accent);
    background: rgba(240, 136, 62, 0.05);
}

/* Heap Blocks */
.heap-block {
    background: var(--surface-hover);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 8px 12px;
    min-width: 90px;
    position: relative;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
    font-family: var(--font-mono);
    animation: heap-bounce 0.35s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}

@keyframes heap-bounce {
    0% { transform: scale(0.4) translateY(12px); opacity: 0; }
    70% { transform: scale(1.08) translateY(-2px); opacity: 1; }
    100% { transform: scale(1) translateY(0); opacity: 1; }
}

/* Trend arrows with spring bounce */
.trend-up {
    color: var(--green);
    font-size: 11px;
    margin-left: 4px;
    display: inline-block;
    animation: trend-up-bounce 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.trend-down {
    color: var(--red);
    font-size: 11px;
    margin-left: 4px;
    display: inline-block;
    animation: trend-down-bounce 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes trend-up-bounce {
    0% { transform: translateY(6px); opacity: 0; }
    60% { transform: translateY(-2px); }
    100% { transform: translateY(0); opacity: 1; }
}

@keyframes trend-down-bounce {
    0% { transform: translateY(-6px); opacity: 0; }
    60% { transform: translateY(2px); }
    100% { transform: translateY(0); opacity: 1; }
}

.heap-addr {
    font-size: 10px;
    color: var(--muted);
    border-bottom: 1px solid var(--border);
    padding-bottom: 4px;
    margin-bottom: 6px;
    text-align: center;
}

.heap-val {
    font-size: 13px;
    color: var(--text);
    text-align: center;
    word-break: break-all;
}

/* History Table */
.history-table {
    width: 100%;
    border-collapse: collapse;
    font-family: var(--font-mono);
    font-size: 12px;
}

.history-table th, .history-table td {
    padding: 8px 14px;
    text-align: left;
    border-bottom: 1px solid rgba(48, 54, 61, 0.4);
}

.history-table th {
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--muted);
    background: rgba(255, 255, 255, 0.02);
}

.history-table tr {
    cursor: pointer;
    transition: background-color 0.15s;
}

.history-table tr:hover {
    background-color: var(--surface-hover);
}

.history-table tr.active-step {
    background-color: rgba(240, 136, 62, 0.12);
    border-left: 3px solid var(--accent);
}

.history-val-cell.changed {
    color: var(--accent);
    font-weight: 600;
}

/* Timeline Footer */
.timeline-bar {
    height: 44px;
    border-top: 1px solid var(--border);
    background-color: var(--surface);
    display: flex;
    align-items: center;
    padding: 0 16px;
    gap: 16px;
    flex-shrink: 0;
    z-index: 200;
}

.controls {
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 150px;
}

.icon-btn {
    background: none;
    border: none;
    color: var(--text);
    cursor: pointer;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 12px;
}

.icon-btn:hover:not(:disabled) {
    background-color: var(--border);
}

.icon-btn:disabled {
    color: var(--muted);
    cursor: not-allowed;
}

#step-counter {
    font-size: 12px;
    font-family: var(--font-mono);
    color: var(--text);
    width: 90px;
    text-align: center;
}

.slider-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    position: relative;
}

#timeline-markers {
    position: relative;
    height: 12px;
    margin: 0 8px;
    pointer-events: none;
    align-self: stretch;
}

input[type=range] {
    width: 100%;
    accent-color: var(--accent);
    cursor: pointer;
}

/* SVG Arrows Overlay */
.arrows-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    pointer-events: none;
    z-index: 1000;
}

.arrow-path {
    fill: none;
    stroke: var(--blue);
    stroke-width: 2;
    opacity: 0.75;
    transition: d 0.1s, stroke-width 0.2s, opacity 0.2s;
}

.arrow-path.highlight {
    stroke: var(--accent);
    stroke-width: 3;
    opacity: 1;
}

/* Monaco active line highlight & inline variable hint */
.my-current-line {
    background-color: var(--highlight-bg) !important;
    border-left: 3px solid var(--accent) !important;
    animation: line-pulse-glow 1.5s infinite alternate cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes line-pulse-glow {
    0% { box-shadow: inset 3px 0 6px var(--accent-glow); }
    100% { box-shadow: inset 3px 0 16px var(--accent-glow); }
}

.inline-variable-hint {
    color: var(--muted) !important;
    font-style: italic !important;
    opacity: 0.8 !important;
    font-family: var(--font-mono) !important;
    font-size: 12px !important;
    user-select: none !important;
}

/* Toast Notification Styles */
.toast-container {
    position: fixed;
    bottom: 56px;
    right: 20px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    z-index: 3000;
    pointer-events: none;
}

.toast {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 16px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-left: 4px solid var(--accent);
    border-radius: 8px;
    color: var(--text);
    font-family: var(--font-main);
    font-size: 13px;
    font-weight: 500;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
    animation: toast-slide-up 0.3s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
    pointer-events: auto;
}

.toast-fade-out {
    opacity: 0;
    transform: translateY(10px) scale(0.95);
    transition: all 0.3s ease;
}

@keyframes toast-slide-up {
    from { opacity: 0; transform: translateY(20px) scale(0.9); }
    to { opacity: 1; transform: translateY(0) scale(1); }
}

/* ── Welcome Onboarding Modal ────────────────────────────────── */
.modal-overlay {
    position: fixed;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.65);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    opacity: 1;
    transition: opacity 0.25s ease;
}

.modal-overlay.hidden {
    opacity: 0;
    pointer-events: none;
}

.modal-card {
    background-color: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 32px;
    width: 440px;
    max-width: 90vw;
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.5);
    animation: modal-pop-in 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.modal-header h2 {
    font-size: 22px;
    font-weight: 700;
    color: var(--accent);
    margin-bottom: 6px;
    letter-spacing: -0.5px;
}

.modal-header p {
    font-size: 13px;
    color: var(--muted);
    margin-bottom: 24px;
}

.modal-options {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.welcome-opt-btn,
.new-file-opt-btn {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 14px 18px;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    color: var(--text);
    cursor: pointer;
    text-align: left;
    transition: transform 0.25s cubic-bezier(0.34, 1.56, 0.64, 1), border-color 0.2s, background-color 0.2s, box-shadow 0.2s;
}

.welcome-opt-btn:hover,
.new-file-opt-btn:hover {
    border-color: var(--accent);
    background: var(--surface-hover);
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 6px 20px var(--accent-glow);
}

.modal-header-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 4px;
}

.modal-close-btn {
    background: none;
    border: none;
    color: var(--muted);
    font-size: 22px;
    cursor: pointer;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
    transition: transform 0.25s cubic-bezier(0.34, 1.56, 0.64, 1), background 0.15s, color 0.15s;
}

.modal-close-btn:hover {
    color: var(--red);
    background: rgba(248, 81, 73, 0.15);
    transform: rotate(90deg) scale(1.15);
}

.modal-subtext {
    font-size: 13px;
    color: var(--muted);
    margin-bottom: 20px;
}

.opt-icon {
    font-size: 26px;
}

.opt-text strong {
    display: block;
    font-size: 15px;
    color: var(--text);
    margin-bottom: 2px;
}

.opt-text small {
    font-size: 12px;
    color: var(--muted);
}

/* Animations & Micro-Interactions */
@keyframes tab-slide-in {
    from { transform: translateY(6px) scale(0.96); opacity: 0; }
    to { transform: translateY(0) scale(1); opacity: 1; }
}

@keyframes modal-pop-in {
    from { transform: scale(0.92) translateY(-6px); opacity: 0; }
    to { transform: scale(1) translateY(0); opacity: 1; }
}

@keyframes flash {
    0% { background-color: var(--accent-glow); }
    100% { background-color: transparent; }
}

@keyframes slide-in {
    from { transform: translateX(12px); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

@keyframes item-pop-in {
    from { transform: translateY(4px) scale(0.98); opacity: 0; }
    to { transform: translateY(0) scale(1); opacity: 1; }
}

@keyframes btn-pulse-glow {
    0%, 100% { box-shadow: 0 3px 12px var(--accent-glow); }
    50% { box-shadow: 0 6px 20px var(--accent-glow), 0 0 10px var(--accent); }
}

/* ── Interactive Element Hover & Active Physics ─────────────── */
.btn.primary {
    animation: btn-pulse-glow 3s infinite ease-in-out;
}

.btn.primary:hover {
    transform: translateY(-2px) scale(1.04);
    box-shadow: 0 8px 22px var(--accent-glow);
}

.btn.primary:active {
    transform: translateY(0) scale(0.95);
}

.icon-btn, .dock-action-btn, .file-tab-add, .panel-toggle-btn {
    transition: transform 0.22s cubic-bezier(0.34, 1.56, 0.64, 1), color 0.15s, background-color 0.15s;
}

.icon-btn:hover, .dock-action-btn:hover, .file-tab-add:hover, .panel-toggle-btn:hover {
    transform: scale(1.15) rotate(4deg);
    color: var(--text);
}

.icon-btn:active, .dock-action-btn:active, .file-tab-add:active, .panel-toggle-btn:active {
    transform: scale(0.92);
}

/* Textarea & Select Focus Halo Rings */
textarea, select, input {
    transition: border-color 0.2s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

textarea:focus, select:focus, input:focus {
    border-color: var(--accent) !important;
    box-shadow: 0 0 0 3px var(--accent-glow) !important;
}

/* Micro-animations on Heap Blocks & Call Stack Frames */
.stack-frame, .heap-block {
    animation: item-pop-in 0.25s cubic-bezier(0.16, 1, 0.3, 1);
    transition: transform 0.18s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.18s, border-color 0.18s;
}

.stack-frame:hover, .heap-block:hover {
    transform: translateX(3px);
    border-left-color: var(--accent) !important;
}

/* ── Layout Preset Switcher Dropdown ───────────────────────── */
.layout-menu-wrapper {
    position: relative;
}

.layout-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    width: 270px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 10px;
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.45);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    z-index: 2500;
    animation: modal-pop-in 0.22s cubic-bezier(0.16, 1, 0.3, 1);
    transform-origin: top right;
}

.layout-dropdown.hidden {
    display: none;
}

.dropdown-header {
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.6px;
    color: var(--muted);
    padding: 4px 8px 8px;
    border-bottom: 1px solid var(--border);
    margin-bottom: 8px;
}

.layout-card-option {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 12px;
    border-radius: 8px;
    cursor: pointer;
    border: 1px solid transparent;
    transition: all 0.2s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.layout-card-option:hover {
    background: var(--surface-hover);
    border-color: var(--accent);
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.25);
}

.layout-card-option.active {
    background: var(--accent-glow);
    border-color: var(--accent);
}

.layout-card-info strong {
    display: block;
    font-size: 13px;
    color: var(--text);
}

.layout-card-info small {
    font-size: 11px;
    color: var(--muted);
}

/* Micro-diagrams for Layout Cards */
.layout-diagram {
    width: 38px;
    height: 28px;
    border: 1px solid var(--border);
    border-radius: 6px;
    background: var(--bg);
    position: relative;
    overflow: hidden;
    flex-shrink: 0;
    transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1), border-color 0.2s;
}

.layout-card-option:hover .layout-diagram {
    transform: scale(1.12);
    border-color: var(--accent);
}

.layout-diagram .d-pane {
    position: absolute;
    background: var(--border);
    border-radius: 1px;
}

.diag-single .main { top: 2px; left: 2px; width: 22px; height: 20px; background: var(--accent); opacity: 0.8; }
.diag-single .side { top: 2px; right: 2px; width: 8px; height: 20px; }

.diag-cp-grid .main { top: 2px; left: 2px; width: 18px; height: 20px; background: var(--accent); opacity: 0.8; }
.diag-cp-grid .top-right { top: 2px; right: 2px; width: 12px; height: 9px; background: var(--blue); }
.diag-cp-grid .bot-right { bottom: 2px; right: 2px; width: 12px; height: 9px; background: var(--green); }

.diag-split .left { top: 2px; left: 2px; width: 14px; height: 20px; background: var(--accent); opacity: 0.8; }
.diag-split .right { top: 2px; right: 2px; width: 14px; height: 20px; background: var(--blue); }

.diag-focus .full { inset: 2px; background: var(--accent); opacity: 0.8; }

/* Cool CP Right Panel (input.txt on top, output.txt on bottom) */
.cp-right-panel {
    display: flex;
    flex-direction: column;
    width: 380px;
    min-width: 200px;
    flex-shrink: 0;
    background-color: var(--surface);
    border-left: 1px solid var(--border);
    overflow: hidden;
}

.cp-right-panel.hidden {
    display: none !important;
}

.cp-input-section {
    flex: 1;
    min-height: 60px;
    display: flex;
    flex-direction: column;
}

#cp-input-textarea {
    flex: 1;
    background-color: var(--bg);
    color: var(--text);
    border: none;
    padding: 10px 14px;
    font-family: var(--font-mono);
    font-size: 13px;
    line-height: 1.5;
    resize: none;
    outline: none;
    user-select: text;
}

#divider-cp-in-out {
    height: 6px;
    min-height: 6px;
    background: var(--border);
    cursor: row-resize;
    transition: background 0.15s;
}

#divider-cp-in-out:hover,
#divider-cp-in-out.dragging {
    background: var(--accent);
}

/* ── Layout Modes ────────────────────────────────────────────── */

/* Resizer hover */
.resize-divider-h:hover,
.resize-divider-h.dragging,
.resize-divider-v:hover,
.resize-divider-v.dragging {
    background: var(--accent) !important;
}

/* --- Hide CP panels by default, show dividers by default --- */
#cp-right-panel,
#divider-cp-lr {
    display: none;
}

#divider-lr {
    display: flex;
    width: 6px;
    min-width: 6px;
    cursor: col-resize;
    background: var(--border);
    flex-shrink: 0;
}

/* ── 1. Standard View (default) ─────────────────────────────── */
/* Left Panel (editor+stdin) on LEFT (order: 1), Resizer in MIDDLE (order: 2), F&L Panel on RIGHT (order: 3) */
.workspace-wrapper.layout-mode-single #left-panel {
    order: 1;
}

.workspace-wrapper.layout-mode-single #divider-lr {
    order: 2;
}

.workspace-wrapper.layout-mode-single #right-panel {
    order: 3;
    width: 320px;
    min-width: 180px;
    border-left: 1px solid var(--border);
    border-right: none;
}

/* ── 2. Split View ──────────────────────────────────────────── */
/* F&L Panel on FAR LEFT (order: 1), Resizer in MIDDLE (order: 2), Left Panel on RIGHT (order: 3) */
.workspace-wrapper.layout-mode-split #right-panel {
    order: 1;
    width: 300px;
    min-width: 150px;
    flex-shrink: 0;
    border-left: none;
    border-right: 1px solid var(--border);
}

.workspace-wrapper.layout-mode-split #divider-lr {
    order: 2;
}

.workspace-wrapper.layout-mode-split #left-panel {
    order: 3;
    display: flex !important;
    flex-direction: row !important;
    flex: 1 1 0% !important;
    min-width: 0 !important;
    overflow: hidden;
}

.workspace-wrapper.layout-mode-split #editor-section {
    flex: 1 1 0% !important;
    min-width: 100px !important;
    overflow: hidden;
}

/* Override base .resize-divider-v (horizontal bar) → vertical bar in split */
.workspace-wrapper.layout-mode-split #divider-editor-stdin {
    align-self: stretch !important;
    width: 6px !important;
    min-width: 6px !important;
    height: auto !important;
    cursor: col-resize !important;
    background: var(--border) !important;
    border-top: none !important;
    border-bottom: none !important;
    border-left: 1px solid var(--border) !important;
    border-right: 1px solid var(--border) !important;
    flex-shrink: 0 !important;
}

.workspace-wrapper.layout-mode-split #stdin-section {
    align-self: stretch !important;
    width: 320px;
    min-width: 150px !important;
    max-width: calc(100% - 150px) !important;
    height: auto !important;
    flex-shrink: 0 !important;
    overflow: hidden;
}

.workspace-wrapper.layout-mode-split .test-fields {
    flex-direction: column !important;
}

.workspace-wrapper.layout-mode-split .test-field-group {
    border-right: none !important;
    border-bottom: 1px solid var(--border);
}

.workspace-wrapper.layout-mode-split #cp-right-panel,
.workspace-wrapper.layout-mode-split #divider-cp-lr {
    display: none !important;
}

/* ── 3. Cool CP Mode ────────────────────────────────────────── */
.workspace-wrapper.layout-mode-cp-grid #right-panel,
.workspace-wrapper.layout-mode-cp-grid #divider-lr,
.workspace-wrapper.layout-mode-cp-grid #stdin-section,
.workspace-wrapper.layout-mode-cp-grid #divider-editor-stdin {
    display: none !important;
}

.workspace-wrapper.layout-mode-cp-grid #divider-cp-lr {
    display: flex !important;
    width: 6px;
    min-width: 6px;
    cursor: col-resize;
    background: var(--border);
    flex-shrink: 0;
}

.workspace-wrapper.layout-mode-cp-grid #cp-right-panel {
    display: flex !important;
    width: 380px;
    min-width: 200px;
    flex-shrink: 0;
}

.workspace-wrapper.layout-mode-cp-grid #bottom-dock {
    display: flex !important;
    height: 220px;
}

/* Hide Program Output tab in Cool CP — output.txt pane is already visible */
.workspace-wrapper.layout-mode-cp-grid .dock-tab[data-tab="tab-output"],
.workspace-wrapper.layout-mode-cp-grid #tab-output {
    display: none !important;
}

/* ── 4. Focus Mode ──────────────────────────────────────────── */
.workspace-wrapper.layout-mode-focus #right-panel,
.workspace-wrapper.layout-mode-focus #divider-lr,
.workspace-wrapper.layout-mode-focus #stdin-section,
.workspace-wrapper.layout-mode-focus #divider-editor-stdin,
.workspace-wrapper.layout-mode-focus #bottom-dock,
.workspace-wrapper.layout-mode-focus #divider-tb,
.workspace-wrapper.layout-mode-focus #cp-right-panel,
.workspace-wrapper.layout-mode-focus #divider-cp-lr {
    display: none !important;
}


/* ══════════════════════════════════════════════════════════════
   TEST SUITE TABS
══════════════════════════════════════════════════════════════ */

.test-suite-header {
    flex-direction: row !important;
    align-items: center !important;
    gap: 0 !important;
    padding: 0 6px 0 0 !important;
    flex-wrap: nowrap;
    overflow: hidden;
    min-height: 32px;
}

.test-tabs-bar {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 2px;
    flex: 1;
    overflow-x: auto;
    scrollbar-width: none;
    padding: 3px 4px;
}
.test-tabs-bar::-webkit-scrollbar { display: none; }

.test-tab {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 3px 10px 3px 8px;
    border-radius: 4px;
    border: 1px solid transparent;
    background: transparent;
    color: var(--text-muted);
    font-size: 11px;
    font-family: inherit;
    cursor: pointer;
    white-space: nowrap;
    transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
    user-select: none;
}
.test-tab:hover { background: var(--surface-2); color: var(--text); }
.test-tab.active {
    background: var(--surface-2);
    color: var(--text);
    border-color: var(--border);
}

.tab-status-dot {
    width: 6px; height: 6px;
    border-radius: 50%;
    flex-shrink: 0;
    background: var(--text-muted);
    transition: background 0.25s ease;
}
.tab-status-dot.status-passed  { background: #3fb950; }
.tab-status-dot.status-wa      { background: #f85149; }
.tab-status-dot.status-re      { background: #e3b341; }
.tab-status-dot.status-tle     { background: #bc8cff; }
.tab-status-dot.status-running { background: var(--accent); animation: pulse-dot-ts 0.8s ease infinite; }

@keyframes pulse-dot-ts {
    0%, 100% { opacity: 1; }
    50%       { opacity: 0.25; }
}

.tab-close {
    opacity: 0;
    font-size: 11px;
    width: 14px; height: 14px;
    display: inline-flex; align-items: center; justify-content: center;
    border: none;
    background: transparent;
    border-radius: 3px;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0;
    transition: opacity 0.15s ease, background 0.15s ease, color 0.15s ease;
    margin-left: 1px;
    line-height: 1;
}
.test-tab:hover .tab-close { opacity: 1; }
.tab-close:hover { background: rgba(248,81,73,0.15); color: #f85149; }

.test-suite-body {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-height: 0;
    overflow: hidden;
}

.test-fields {
    display: flex;
    flex-direction: row;
    flex: 1;
    min-height: 0;
    overflow: hidden;
}

.test-field-group {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-width: 0;
    overflow: hidden;
    border-right: 1px solid var(--border);
}
.test-field-group:last-child { border-right: none; }

.test-field-label {
    display: block;
    font-size: 10px;
    font-weight: 600;
    letter-spacing: 0.07em;
    text-transform: uppercase;
    color: var(--text-muted);
    padding: 4px 10px;
    border-bottom: 1px solid var(--border);
    background: var(--surface);
    flex-shrink: 0;
}

.test-textarea {
    flex: 1;
    min-height: 0;
    background: var(--bg);
    color: var(--text);
    border: none;
    outline: none;
    padding: 8px 10px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 12px;
    resize: none;
    width: 100%;
    box-sizing: border-box;
    transition: background 0.15s ease;
}
.test-textarea:focus { background: var(--surface-2); }

.test-actual-output {
    display: flex;
    flex-direction: column;
    min-height: 52px;
    max-height: 130px;
    border-top: 1px solid var(--border);
    flex-shrink: 0;
}

.actual-output-content {
    flex: 1;
    overflow-y: auto;
    padding: 6px 12px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 12px;
    white-space: pre-wrap;
    color: var(--text);
    background: var(--bg);
}
.actual-output-content.status-passed { border-left: 3px solid #3fb950; }
.actual-output-content.status-wa     { border-left: 3px solid #f85149; }
.actual-output-content.status-re     { border-left: 3px solid #e3b341; }

.verdict-banner {
    padding: 8px 14px;
    border-radius: 5px;
    font-size: 12px;
    font-weight: 700;
    margin-bottom: 8px;
    font-family: 'JetBrains Mono', monospace;
    letter-spacing: 0.03em;
}
.verdict-ok { background: rgba(63,185,80,0.1);  color: #3fb950; border: 1px solid rgba(63,185,80,0.3); }
.verdict-wa { background: rgba(248,81,73,0.1);  color: #f85149; border: 1px solid rgba(248,81,73,0.3); }

.output-test-row {
    margin-bottom: 8px;
    padding: 7px 10px;
    border-radius: 5px;
    background: var(--surface);
    border: 1px solid var(--border);
    font-size: 12px;
}
.output-test-pre {
    margin: 5px 0 0 0;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    white-space: pre-wrap;
    color: var(--text-muted);
    max-height: 80px;
    overflow-y: auto;
}

/* ══════════════════════════════════════════════════════════════
   PROBLEM IMPORTER MODAL
══════════════════════════════════════════════════════════════ */

.import-modal-card { max-width: 560px; width: 92%; }

.import-tabs {
    display: flex;
    border-bottom: 1px solid var(--border);
    margin: 12px -24px 0;
    padding: 0 24px;
}

.import-tab {
    background: none;
    border: none;
    border-bottom: 2px solid transparent;
    color: var(--text-muted);
    padding: 8px 14px;
    font-size: 12px;
    cursor: pointer;
    margin-bottom: -1px;
    font-family: inherit;
    transition: color 0.15s, border-color 0.15s;
}
.import-tab.active { color: var(--accent); border-bottom-color: var(--accent); }
.import-tab:hover  { color: var(--text); }

.import-tab-body { padding: 16px 0 4px 0; }

.import-hint {
    color: var(--text-muted);
    font-size: 12px;
    margin: 0 0 12px 0;
    line-height: 1.5;
}
.import-hint code {
    background: var(--surface-2);
    padding: 1px 6px;
    border-radius: 3px;
    font-size: 11px;
    font-family: 'JetBrains Mono', monospace;
}

.import-url-row { display: flex; gap: 8px; }

.import-url-field {
    flex: 1;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 5px;
    color: var(--text);
    padding: 7px 10px;
    font-size: 12px;
    font-family: 'JetBrains Mono', monospace;
    outline: none;
    transition: border-color 0.2s;
}
.import-url-field:focus { border-color: var(--accent); }

.import-status-msg {
    margin-top: 10px;
    font-size: 12px;
    min-height: 18px;
    color: var(--text-muted);
}
.import-status-msg.ok  { color: #3fb950; }
.import-status-msg.err { color: #f85149; }

.import-raw-area {
    width: 100%;
    height: 110px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 5px;
    color: var(--text);
    padding: 8px 10px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    resize: vertical;
    outline: none;
    box-sizing: border-box;
    transition: border-color 0.2s;
}
.import-raw-area:focus { border-color: var(--accent); }

.import-raw-actions { display: flex; gap: 8px; margin-top: 10px; }

.import-cc-status {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 7px 10px;
    background: var(--surface);
    border-radius: 5px;
    border: 1px solid var(--border);
    margin-bottom: 14px;
    font-size: 11px;
    color: var(--text-muted);
}
.cc-dot {
    width: 7px; height: 7px;
    border-radius: 50%;
    background: var(--text-muted);
    flex-shrink: 0;
    transition: background 0.3s;
}
.cc-dot.listening { background: #e3b341; animation: pulse-dot-ts 1.2s ease infinite; }
.cc-dot.connected { background: #3fb950; animation: none; }