:root {
    --bg-color: #f0f4f9;
    --panel-bg: #ffffff;
    --border-color: #d1d9e6;
    --accent-color: #1a73e8;
    --accent-hover: #1557b0;
    --text-main: #1f1f1f;
    --text-secondary: #5f6368;
    --font-main: 'Outfit', 'Inter', sans-serif;
    --header-height: 60px;
    --blue-gradient: linear-gradient(135deg, #1a73e8, #0d47a1);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

/* Header */
header {
    height: var(--header-height);
    background: var(--blue-gradient);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 100;
    box-shadow: 0 4px 12px rgba(26, 115, 232, 0.2);
}

.header-left {
    display: flex;
    align-items: center;
    gap: 20px;
}

.logo {
    font-weight: 800;
    font-size: 1.5rem;
    letter-spacing: -1px;
    color: #ffffff;
    display: flex;
    align-items: center;
}

.logo span {
    color: #ffd700; /* Gold/Yellow for contrast against blue */
}

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

.btn {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #ffffff;
    padding: 8px 16px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all 0.2s ease;
}

.btn:hover {
    background-color: var(--button-hover);
    border-color: var(--accent-color);
}

.btn-primary {
    background-color: #444;
    border: none;
}

.btn-blue {
    background-color: var(--accent-color);
    border: none;
    font-weight: 500;
}

.btn-blue:hover {
    background-color: #039be5;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 20px;
}

.header-right a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
}

.header-right a:hover {
    color: var(--text-primary);
}

.user-profile {
    display: flex;
    align-items: center;
    gap: 8px;
}

/* Main Layout */
main {
    flex: 1;
    display: flex;
    overflow: hidden;
}

/* Editor Section */
#editor-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    background-color: #1e1e1e;
    border-right: 1px solid var(--border-color);
    min-width: 300px;
}

/* Blockly & Preview */
#blockly-div {
    flex: 1;
    width: 100%;
    background: #181818;
    border: none;
}

#code-preview {
    flex: 1;
    background-color: #1e1e1e;
    color: #d4d4d4;
    font-family: var(--font-mono);
    font-size: 14px;
    padding: 20px;
    line-height: 1.5;
    overflow-y: auto;
    border-left: 1px solid var(--border-color);
}

.tab {
    padding: 12px 24px;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: all 0.2s;
    user-select: none;
}

.tab.active {
    color: var(--accent-color);
    border-bottom: 2px solid var(--accent-color);
    background: #e8f0fe;
}

/* Simulation Section */
#simulation-container {
    flex: 1.2;
    flex: 1;
    display: flex;
    flex-direction: column;
    background-color: #d0d0d0;
    position: relative;
}

.sim-header {
    height: 50px;
    background-color: #ffffff;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    padding: 0 20px;
    justify-content: space-between;
    box-shadow: 0 2px 4px rgba(0,0,0,0.02);
}

.sim-controls {
    position: absolute;
    top: 60px;
    left: 20px;
    display: flex;
    gap: 12px;
    z-index: 10;
}

.zoom-controls {
    display: flex;
    align-items: center;
    gap: 8px;
    background: #ffffff;
    padding: 4px 12px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.zoom-btn {
    background: #f8f9fa;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-weight: 600;
    font-size: 16px;
    color: var(--accent-color);
    transition: all 0.2s;
}

.zoom-btn:hover {
    background: #f0f0f0;
    border-color: #666;
}

.zoom-btn:active {
    background: #ddd;
}

#zoom-level {
    font-size: 0.75rem;
    font-family: var(--font-mono);
    min-width: 40px;
    text-align: center;
    color: #444;
}

.control-btn {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
    transition: transform 0.2s, background-color 0.2s;
    color: white;
}

.control-btn:hover {
    transform: scale(1.1);
}

.btn-play {
    background-color: #34a853; /* Success green fits well with blue */
}

.btn-play:hover {
    background-color: #2d9249;
}

.btn-add {
    background: var(--blue-gradient);
}

.btn-camera {
    background: linear-gradient(135deg, #9c27b0, #673ab7);
}

.btn-more {
    background-color: #5f6368;
}

.canvas-area {
    flex: 1;
    display: flex;
    overflow: auto;
    background-color: #d0d0d0;
    position: relative;
}

#canvas-content {
    background-image: radial-gradient(#999 1px, transparent 1px);
    background-size: 20px 20px;
}

/* Component Menu */
.component-menu {
    position: absolute;
    top: 110px;
    left: 20px;
    background-color: var(--panel-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    width: 320px;
    max-height: 500px;
    display: none;
    flex-direction: column;
    box-shadow: 0 10px 30px rgba(26, 115, 232, 0.15);
    z-index: 100;
    overflow: hidden;
}

.menu-body {
    overflow-y: auto;
    flex: 1;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 6px;
    padding: 10px;
}

.component-menu.active {
    display: flex;
}

.menu-header {
    padding: 12px 14px;
    background: var(--blue-gradient);
    color: #ffffff;
    font-weight: 700;
    font-size: 0.9rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.menu-search {
    width: 100%;
    padding: 8px 12px;
    border: none;
    border-radius: 8px;
    background: rgba(255,255,255,0.2);
    color: #fff;
    font-size: 0.85rem;
    outline: none;
    backdrop-filter: blur(4px);
}

.menu-search::placeholder {
    color: rgba(255,255,255,0.6);
}

.menu-item {
    padding: 8px 6px;
    cursor: pointer;
    font-size: 0.72rem;
    transition: all 0.2s;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    border-radius: 8px;
    text-align: center;
    line-height: 1.2;
    min-height: 80px;
    justify-content: center;
}

.menu-item:hover {
    background-color: #e8f0fe;
    color: var(--accent-color);
    transform: scale(1.05);
}

.menu-item-icon {
    width: 48px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: none;
}

.menu-item-icon > * {
    max-width: 48px;
    max-height: 36px;
    transform-origin: center;
}

/* Draggable Wrapper */
.draggable-component {
    position: absolute;
    cursor: move;
    user-select: none;
    padding: 5px;
    transition: transform 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.draggable-component:hover {
    outline: 1px dashed var(--accent-color);
}

.draggable-component.selected {
    outline: 2px solid var(--accent-color);
    background-color: rgba(41, 182, 246, 0.05);
    border-radius: 4px;
}

.draggable-component.dragging {
    opacity: 0.8;
    z-index: 1000;
    outline: 2px solid var(--accent-color);
}

.board-badge {
    position: absolute;
    top: -25px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--blue-gradient);
    color: white;
    padding: 2px 10px;
    border-radius: 20px;
    font-size: 11px;
    font-weight: 700;
    white-space: nowrap;
    pointer-events: none;
    box-shadow: 0 2px 8px rgba(26, 115, 232, 0.3);
    z-index: 10;
    border: 1px solid rgba(255, 255, 255, 0.2);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.draggable-component.selected .board-badge {
    background: linear-gradient(135deg, #ea4335, #c5221f);
    box-shadow: 0 2px 8px rgba(234, 67, 53, 0.4);
}

/* Quick Actions Panel */
.quick-actions {
    position: absolute;
    background: rgba(30, 35, 45, 0.92);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: 10px;
    padding: 10px 14px;
    display: none;
    flex-direction: column;
    gap: 6px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.35);
    z-index: 110;
    pointer-events: all;
    animation: fadeIn 0.2s ease-out;
    color: #fff;
    min-width: 200px;
}

.quick-actions .sim-title {
    font-size: 0.85rem;
    font-weight: 700;
    color: #fff;
    padding-bottom: 4px;
    border-bottom: 1px solid rgba(255,255,255,0.15);
    margin-bottom: 2px;
}

.quick-actions .sim-label {
    font-size: 0.75rem;
    color: rgba(255,255,255,0.7);
    display: flex;
    align-items: center;
    gap: 8px;
}

.quick-actions .sim-value {
    color: #64b5f6;
    font-weight: 600;
    min-width: 45px;
    text-align: right;
}

.quick-actions input[type='range'] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: rgba(255,255,255,0.15);
    outline: none;
}

.quick-actions input[type='range']::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: #64b5f6;
    cursor: pointer;
    box-shadow: 0 0 6px rgba(100,181,246,0.5);
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-5px); }
    to { opacity: 1; transform: translateY(0); }
}

.action-btn {
    background: rgba(255,255,255,0.08);
    border: 1px solid rgba(255,255,255,0.1);
    padding: 6px 12px;
    text-align: left;
    font-size: 0.82rem;
    font-weight: 600;
    cursor: pointer;
    border-radius: 6px;
    display: flex;
    align-items: center;
    gap: 8px;
    color: #e0e0e0;
    transition: all 0.2s;
}

.action-btn:hover {
    background: rgba(255,255,255,0.15);
    color: #fff;
}

.action-btn.primary {
    color: #81c784;
}

.action-btn.primary:hover {
    background: rgba(76, 175, 80, 0.2);
}

.action-btn.danger {
    color: #ef5350;
}

.action-btn.danger:hover {
    background: rgba(244, 67, 54, 0.2);
}

/* --- Premium Blockly Customization (MakeCode Style) --- */
.blocklyToolboxDiv {
    background-color: #ffffff !important;
    border-right: 1px solid #e0e0e0 !important;
    width: 180px !important;
    box-shadow: none !important;
}

.blocklyTreeRow {
    padding: 15px 12px 15px 12px !important;
    margin: 0 !important;
    border-radius: 0 !important;
    border-left: 8px solid transparent;
    transition: all 0.2s ease !important;
    height: 54px !important;
    display: flex !important;
    align-items: center !important;
}

.blocklyTreeRow:hover {
    background-color: #f5f5f5 !important;
}

.blocklyTreeSelected {
    background-color: #f0f7ff !important;
}

/* Color Indicators for Categories (Robust Class-based selectors) */
.cat-logic .blocklyTreeRow { border-left-color: #2196F3 !important; }
.cat-loops .blocklyTreeRow { border-left-color: #4CAF50 !important; }
.cat-math .blocklyTreeRow { border-left-color: #FFC107 !important; }
.cat-arduino .blocklyTreeRow { border-left-color: #009688 !important; }
.cat-ai .blocklyTreeRow { border-left-color: #9c27b0 !important; }
.cat-actuators .blocklyTreeRow { border-left-color: #4CAF50 !important; }
.cat-sensors .blocklyTreeRow { border-left-color: #2196F3 !important; }
.cat-displays .blocklyTreeRow { border-left-color: #FF9800 !important; }
.cat-inputs .blocklyTreeRow { border-left-color: #FFC107 !important; }
.cat-variables .blocklyTreeRow { border-left-color: #E91E63 !important; }

.blocklyTreeLabel {
    font-size: 1.1rem !important;
    font-weight: 700 !important;
    color: #333 !important;
    font-family: var(--font-main) !important;
    margin-left: 8px !important;
}

.blocklyTreeIcon {
    display: none !important; /* Hide default small arrow icons */
}

.blocklyTreeSelected .blocklyTreeLabel {
    color: var(--accent-color) !important;
}

.blocklyFlyoutBackground {
    fill: #f8f9fa !important;
    fill-opacity: 1 !important;
    stroke: #e0e0e0 !important;
}

.blocklyBlockCanvas {
    /* Improve block contrast on light background */
}

.blocklyTreeIcon {
    opacity: 0.7;
    margin-right: 10px !important;
}

/* Scrollbar for toolbox */
.blocklyToolboxDiv::-webkit-scrollbar {
    width: 4px;
}

.blocklyToolboxDiv::-webkit-scrollbar-thumb {
    background: #444;
    border-radius: 2px;
}

.blocklyMainBackground {
    stroke: none !important;
}

.blocklyFlyoutBackground {
    fill: #1a1a1a !important;
    fill-opacity: 0.95 !important;
}

.blocklyFlyoutLabelText {
    font-family: var(--font-main) !important;
    font-weight: bold !important;
    fill: #fff !important;
}

.blocklyText {
    font-family: var(--font-main) !important;
}

/* Zoom controls inside Blockly */
.blocklyZoom>image {
    opacity: 0.6;
    transition: opacity 0.2s;
}

.blocklyZoom>image:hover {
    opacity: 1;
}

/* ========================================
   RESPONSIVE DESIGN - Mobile & Tablet
   ======================================== */

/* Tablet (Portrait) - 768px and below */
@media (max-width: 768px) {
    :root {
        --header-height: 50px;
    }

    header {
        padding: 0 12px;
        height: var(--header-height);
    }

    .logo {
        font-size: 18px;
    }

    .header-actions {
        gap: 8px;
    }

    .btn {
        padding: 6px 12px;
        font-size: 13px;
    }

    .btn-icon {
        padding: 6px;
    }

    /* Adjust main container */
    .container {
        flex-direction: column;
    }

    #blockly-container {
        height: 40vh;
        min-height: 300px;
    }

    #simulator-container {
        height: 60vh;
        min-height: 400px;
    }

    /* Simulator controls */
    .simulator-controls {
        padding: 8px;
        gap: 8px;
    }

    .zoom-controls {
        gap: 4px;
    }

    /* Component menu */
    .component-menu {
        max-height: 50vh;
        width: 90%;
        left: 5%;
        right: 5%;
    }

    /* Quick actions panel */
    .quick-actions {
        transform: scale(0.9);
    }

    /* Footer adjustment */
    footer {
        padding: 8px 12px !important;
        font-size: 12px !important;
    }

    footer div {
        flex-wrap: wrap;
        gap: 4px !important;
    }
}

/* Mobile (Portrait) - 480px and below */
@media (max-width: 480px) {
    :root {
        --header-height: 48px;
    }

    header {
        padding: 0 8px;
    }

    .logo {
        font-size: 16px;
    }

    .header-left {
        gap: 8px;
    }

    .header-actions {
        gap: 4px;
    }

    .btn {
        padding: 5px 10px;
        font-size: 12px;
    }

    .btn-icon {
        padding: 5px;
        width: 32px;
        height: 32px;
    }

    /* Hide text in buttons on very small screens */
    .btn:not(.btn-icon) span {
        display: none;
    }

    /* Blockly container */
    #blockly-container {
        height: 35vh;
        min-height: 250px;
    }

    #simulator-container {
        height: 65vh;
    }

    /* Simulator controls */
    .simulator-controls {
        padding: 6px;
        gap: 6px;
        flex-wrap: wrap;
    }

    .zoom-controls {
        order: -1;
        width: 100%;
        justify-content: center;
    }

    /* Component menu */
    .component-menu {
        width: 95%;
        left: 2.5%;
        right: 2.5%;
        max-height: 60vh;
    }

    .component-item {
        padding: 10px;
        font-size: 13px;
    }

    /* Quick actions */
    .quick-actions {
        transform: scale(0.85);
    }

    .quick-actions button {
        padding: 6px 10px;
        font-size: 11px;
    }

    /* Serial output */
    .serial-output {
        font-size: 11px;
        padding: 8px;
    }

    /* Footer */
    footer {
        padding: 6px 8px !important;
        font-size: 11px !important;
    }

    footer span {
        font-size: 10px !important;
    }
}

/* Touch-friendly improvements */
@media (hover: none) and (pointer: coarse) {
    /* Increase touch targets */
    .btn {
        min-height: 44px;
        min-width: 44px;
    }

    .btn-icon {
        min-width: 44px;
        min-height: 44px;
    }

    .component-item {
        min-height: 48px;
        padding: 12px;
    }

    /* Prevent text selection on touch */
    * {
        -webkit-user-select: none;
        user-select: none;
        -webkit-touch-callout: none;
    }

    /* Allow text selection in specific areas */
    .serial-output,
    input,
    textarea {
        -webkit-user-select: text;
        user-select: text;
    }

    /* Improve draggable components for touch */
    .draggable-component {
        touch-action: none;
        cursor: grab;
    }

    .draggable-component.dragging {
        cursor: grabbing;
        opacity: 0.8;
    }

    /* Wire palette touch improvements */
    .wire-palette {
        padding: 12px;
    }

    .palette-color {
        min-width: 44px;
        min-height: 44px;
    }
}

/* Landscape mode adjustments */
@media (max-width: 768px) and (orientation: landscape) {
    #blockly-container {
        height: 50vh;
    }

    #simulator-container {
        height: 50vh;
    }

    .component-menu {
        max-height: 70vh;
    }
}

/* High DPI screens */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    /* Improve rendering on retina displays */
    .wire {
        stroke-width: 2.5;
    }

    .pin-indicator {
        border-width: 2px;
    }
/* Camera Panel */
.camera-panel {
    position: absolute;
    top: 60px;
    right: 20px;
    width: 320px;
    background: #ffffff;
    border-radius: 16px;
    box-shadow: 0 12px 40px rgba(0,0,0,0.2);
    z-index: 200;
    display: none;
    flex-direction: column;
    overflow: hidden;
    border: 1px solid rgba(0,0,0,0.1);
    animation: slideInRight 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes slideInRight {
    from { opacity: 0; transform: translateX(30px); }
    to { opacity: 1; transform: translateX(0); }
}

.camera-panel.active {
    display: flex;
}

.camera-header {
    background: linear-gradient(135deg, #9c27b0, #673ab7);
    color: white;
    padding: 12px 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: 600;
    font-size: 0.9rem;
}

.camera-header button {
    background: none;
    border: none;
    color: white;
    font-size: 24px;
    cursor: pointer;
    line-height: 1;
    opacity: 0.8;
    transition: opacity 0.2s;
}

.camera-header button:hover {
    opacity: 1;
}

#webcam-container {
    width: 320px;
    height: 240px;
    background: #000;
    display: flex;
    align-items: center;
    justify-content: center;
}

#webcam-container canvas {
    width: 100% !important;
    height: 100% !important;
    object-fit: cover;
}

#label-container {
    padding: 12px;
    max-height: 150px;
    overflow-y: auto;
    background: #f8f9fa;
}

.label-row {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 6px;
    font-size: 0.85rem;
}

.label-name {
    flex: 1;
    font-weight: 500;
    color: #444;
}

.label-bar-bg {
    width: 120px;
    height: 8px;
    background: #e0e0e0;
    border-radius: 4px;
    overflow: hidden;
}

.label-bar-fill {
    height: 100%;
    background: #9c27b0;
    border-radius: 4px;
    transition: width 0.1s ease;
}

.label-percent {
    width: 35px;
    text-align: right;
    font-size: 0.75rem;
    font-weight: 600;
    color: #666;
}
}