/* ==========================================================================
   PRACTICE LAB — VS Code–Inspired IDE + Hub Styles
   Code Within · Placement Training Platform
   ========================================================================== */

/* ==========================================================================
   1. HUB VIEW — Landing Page with Level Cards
   ========================================================================== */

.practice-hub {
    animation: fadeInUp 0.4s ease;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(16px); }
    to   { opacity: 1; transform: translateY(0); }
}

/* Hub Hero */
.practice-hub-hero {
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, rgba(237,233,254,0.5) 0%, rgba(239,246,255,0.4) 40%, rgba(240,253,244,0.3) 100%);
    border: 1px solid rgba(108,76,232,0.12);
    border-radius: 20px;
    padding: 48px 40px;
    text-align: center;
    margin-bottom: 36px;
}

.practice-hub-hero::before {
    content: '';
    position: absolute;
    top: -80px; right: -60px;
    width: 280px; height: 280px;
    background: radial-gradient(circle, rgba(108,76,232,0.1) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

.practice-hub-hero .hub-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(255,255,255,0.85);
    backdrop-filter: blur(8px);
    border: 1px solid rgba(108,76,232,0.18);
    padding: 5px 16px;
    border-radius: 9999px;
    font-size: 12.5px;
    font-weight: 700;
    color: var(--accent-purple);
    margin-bottom: 18px;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.practice-hub-hero h1 {
    font-size: 40px;
    font-weight: 800;
    letter-spacing: -1px;
    color: var(--text-primary);
    margin: 0 0 12px 0;
    line-height: 1.15;
}

.practice-hub-hero h1 .gradient-text {
    background: linear-gradient(135deg, #6C4CE8, #0EA5E9, #10B981);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.practice-hub-hero > p {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.65;
    max-width: 640px;
    margin: 0 auto;
}

/* Levels Grid */
.levels-section-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 22px;
}

.levels-section-header .section-badge {
    background: var(--purple-light);
    color: var(--accent-purple);
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    padding: 4px 12px;
    border-radius: 7px;
    border: 1px solid rgba(108,76,232,0.15);
}

.levels-section-header h2 {
    font-size: 24px;
    font-weight: 800;
    color: var(--text-primary);
    margin: 0;
    letter-spacing: -0.3px;
}

.practice-levels-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-bottom: 44px;
}

@media (max-width: 1100px) { .practice-levels-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px)  { .practice-levels-grid { grid-template-columns: 1fr; } }

.practice-level-card {
    background: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 24px;
    box-shadow: var(--shadow-card);
    transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
    position: relative;
    overflow: hidden;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.practice-level-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 3.5px;
    background: linear-gradient(90deg, #6C4CE8, #0EA5E9);
    border-radius: 16px 16px 0 0;
    opacity: 0;
    transition: opacity 0.2s ease;
}

.practice-level-card:hover::before { opacity: 1; }
.practice-level-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
    border-color: rgba(108,76,232,0.25);
}

.practice-level-card.is-locked {
    opacity: 0.55;
    cursor: not-allowed;
    filter: grayscale(0.3);
}

.practice-level-card.is-locked:hover {
    transform: none;
    box-shadow: var(--shadow-card);
}

.level-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.level-card-number {
    width: 42px; height: 42px;
    border-radius: 12px;
    background: linear-gradient(135deg, #EDE9FE, #DDD6FE);
    border: 1px solid rgba(108,76,232,0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 15px;
    font-weight: 800;
    color: var(--accent-purple);
    font-family: 'JetBrains Mono', Consolas, monospace;
}

.level-card-stars {
    display: flex;
    gap: 2px;
    font-size: 14px;
}

.level-card-stars .star-filled { color: #FBBF24; }
.level-card-stars .star-empty  { color: #E2E8F0; }

.practice-level-card h3 {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0;
    letter-spacing: -0.01em;
}

.practice-level-card .level-desc {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.55;
    margin: 0;
    flex: 1;
}

.level-skills-row {
    display: flex;
    gap: 5px;
    flex-wrap: wrap;
}

.level-skill-chip {
    font-size: 10.5px;
    font-weight: 600;
    padding: 2px 8px;
    border-radius: 5px;
    background: var(--bg-primary);
    color: var(--text-muted);
    border: 1px solid var(--border-color);
    font-family: 'JetBrains Mono', Consolas, monospace;
}

.level-card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 12px;
    border-top: 1px solid var(--border-subtle);
}

.level-progress-bar {
    flex: 1;
    height: 6px;
    background: #F1F5F9;
    border-radius: 9999px;
    overflow: hidden;
    margin-right: 10px;
}

.level-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #6C4CE8, #0EA5E9);
    border-radius: 9999px;
    transition: width 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

.level-progress-text {
    font-size: 11.5px;
    font-weight: 700;
    color: var(--text-muted);
    white-space: nowrap;
}

.level-start-btn {
    background: var(--accent-purple);
    color: #FFFFFF;
    border: none;
    border-radius: 8px;
    padding: 8px 16px;
    font-size: 12.5px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.15s ease;
    display: inline-flex;
    align-items: center;
    gap: 5px;
}

.level-start-btn:hover {
    background: var(--purple-hover);
    transform: translateY(-1px);
}

/* Exam Strategy Section */
.practice-strategy-banner {
    background: linear-gradient(135deg, #0F172A, #1E293B);
    border-radius: 18px;
    padding: 36px 40px;
    margin-bottom: 44px;
    position: relative;
    overflow: hidden;
}

.practice-strategy-banner::before {
    content: '';
    position: absolute;
    top: -50px; right: -30px;
    width: 180px; height: 180px;
    background: radial-gradient(circle, rgba(108,76,232,0.25) 0%, transparent 70%);
    border-radius: 50%;
    pointer-events: none;
}

.practice-strategy-banner h3 {
    color: #FFFFFF;
    font-size: 22px;
    font-weight: 800;
    margin: 0 0 20px 0;
    position: relative;
    z-index: 1;
}

.strategy-steps {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 16px;
    position: relative;
    z-index: 1;
}

@media (max-width: 960px) { .strategy-steps { grid-template-columns: repeat(3, 1fr); } }
@media (max-width: 560px) { .strategy-steps { grid-template-columns: 1fr; } }

.strategy-step {
    background: rgba(255,255,255,0.06);
    border: 1px solid rgba(255,255,255,0.08);
    border-radius: 12px;
    padding: 16px;
    text-align: center;
}

.strategy-step .step-num {
    width: 30px; height: 30px;
    border-radius: 50%;
    background: linear-gradient(135deg, #6C4CE8, #8B5CF6);
    color: #FFFFFF;
    font-size: 13px;
    font-weight: 800;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 8px auto;
}

.strategy-step h4 {
    color: #F8FAFC;
    font-size: 13px;
    font-weight: 700;
    margin: 0 0 4px 0;
}

.strategy-step p {
    color: #94A3B8;
    font-size: 11.5px;
    line-height: 1.5;
    margin: 0;
}


/* ==========================================================================
   2. IDE VIEW — VS Code–Inspired 3-Panel Workspace
   ========================================================================== */

.practice-ide {
    animation: fadeInUp 0.35s ease;
}

/* IDE Toolbar */
.ide-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 12px 0;
    margin-bottom: 6px;
    flex-wrap: wrap;
}

.ide-back-btn {
    background: #FFFFFF;
    border: 1.5px solid var(--border-color);
    border-radius: 9999px;
    padding: 7px 18px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all 0.15s ease;
}

.ide-back-btn:hover {
    background: var(--purple-light);
    color: var(--accent-purple);
    border-color: var(--accent-purple);
}

.ide-toolbar-center {
    display: flex;
    align-items: center;
    gap: 10px;
    flex: 1;
    justify-content: center;
}

.ide-question-badge {
    font-size: 12px;
    font-weight: 700;
    color: var(--accent-purple);
    background: var(--purple-light);
    padding: 4px 12px;
    border-radius: 7px;
    border: 1px solid rgba(108,76,232,0.15);
}

.ide-question-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.ide-toolbar-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

.ide-action-btn {
    background: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 7px 14px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.15s ease;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.ide-action-btn:hover {
    border-color: var(--accent-purple);
    color: var(--accent-purple);
    background: var(--purple-light);
}

.ide-maximize-btn.is-active {
    background: linear-gradient(135deg, #6C4CE8, #8B5CF6);
    color: #FFFFFF;
    border-color: transparent;
    box-shadow: 0 2px 10px rgba(108, 76, 232, 0.3);
}

.ide-nav-btn {
    background: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 7px 14px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.15s ease;
}

.ide-nav-btn:hover {
    border-color: var(--accent-purple);
    color: var(--accent-purple);
    background: var(--purple-light);
}

.ide-nav-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.ide-nav-btn:disabled:hover {
    background: #FFFFFF;
    border-color: var(--border-color);
    color: var(--text-secondary);
}

/* 3-Panel Layout with Draggable Splitters */
.ide-panels {
    display: flex;
    flex-direction: row;
    align-items: stretch;
    gap: 0;
    min-height: 640px;
    margin-bottom: 10px;
    width: 100%;
    position: relative;
    box-sizing: border-box;
}

@media (max-width: 1100px) {
    .ide-panels {
        flex-direction: column;
        min-height: auto;
        gap: 16px;
    }
}

/* ==========================================================================
   DRAGGABLE SPLITTERS (RESIZERS)
   ========================================================================== */
.ide-resizer {
    width: 12px;
    cursor: col-resize;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    z-index: 10;
    flex-shrink: 0;
    user-select: none;
    touch-action: none;
    margin: 0 -2px;
    transition: background 0.15s ease;
}

.ide-resizer:hover,
.ide-resizer.is-dragging {
    background: rgba(108, 76, 232, 0.12);
}

.ide-resizer .resizer-handle {
    width: 4px;
    height: 38px;
    border-radius: 4px;
    background: #CBD5E1;
    transition: all 0.15s ease;
    pointer-events: none;
}

.ide-resizer:hover .resizer-handle,
.ide-resizer.is-dragging .resizer-handle {
    background: var(--accent-purple);
    height: 56px;
    box-shadow: 0 0 10px rgba(108, 76, 232, 0.45);
}

@media (max-width: 1100px) {
    .ide-resizer {
        display: none !important;
    }
}

/* While actively dragging, disable text selection & iframe interactions */
body.is-resizing {
    user-select: none !important;
    cursor: col-resize !important;
}

body.is-resizing iframe {
    pointer-events: none !important;
}

body.is-resizing-v {
    user-select: none !important;
    cursor: row-resize !important;
}

body.is-resizing-v iframe {
    pointer-events: none !important;
}

/* ==========================================================================
   MAXIMIZED WORKSPACE (FULLSCREEN)
   ========================================================================== */
body.is-ide-maximized {
    overflow: hidden !important;
}

body.is-ide-maximized .nevigation {
    display: none !important;
}

body.is-ide-maximized .home-page {
    max-width: 100vw !important;
    width: 100vw !important;
    padding: 10px 16px 12px 16px !important;
    margin: 0 !important;
    height: 100vh !important;
    box-sizing: border-box !important;
}

body.is-ide-maximized #ideView {
    height: 100% !important;
    display: flex !important;
    flex-direction: column !important;
}

body.is-ide-maximized .ide-panels {
    flex: 1 !important;
    height: calc(100vh - 68px) !important;
    min-height: 0 !important;
    margin-bottom: 0 !important;
}

body.is-ide-maximized .ide-panel-question,
body.is-ide-maximized .ide-panel-editor,
body.is-ide-maximized .ide-panel-preview {
    max-height: none !important;
    height: 100% !important;
}

/* Left Panel — Question */
.ide-panel-question {
    width: 320px;
    min-width: 200px;
    max-width: 650px;
    flex-shrink: 0;
    background: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 14px;
    overflow-x: hidden;
    overflow-y: auto;
    max-height: 660px;
    box-shadow: var(--shadow-subtle);
    display: flex;
    flex-direction: column;
    box-sizing: border-box;
    overflow-wrap: break-word;
    word-wrap: break-word;
}

.question-panel-header {
    padding: 16px 20px 12px;
    border-bottom: 1px solid var(--border-subtle);
    position: sticky;
    top: 0;
    background: #FFFFFF;
    z-index: 2;
    border-radius: 14px 14px 0 0;
    overflow-wrap: break-word;
    word-break: break-word;
}

.question-panel-header h3 {
    font-size: 14px;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0 0 6px 0;
    display: flex;
    align-items: center;
    gap: 7px;
    overflow-wrap: break-word;
    word-break: break-word;
}

.question-difficulty {
    font-size: 12px;
    display: flex;
    gap: 2px;
}

.question-panel-body {
    padding: 16px 20px 20px;
    flex: 1;
    overflow-wrap: break-word;
    word-wrap: break-word;
    word-break: break-word;
}

.question-task {
    font-size: 13.5px;
    color: var(--text-secondary);
    line-height: 1.65;
    margin-bottom: 16px;
    overflow-wrap: break-word;
    word-wrap: break-word;
    word-break: break-word;
    white-space: normal;
}

.question-task p {
    margin: 0 0 10px 0;
    overflow-wrap: break-word;
    word-wrap: break-word;
    word-break: break-word;
    white-space: normal;
}

.question-task ol,
.question-task ul {
    padding-left: 20px;
    margin: 10px 0 12px 0;
}

.question-task li {
    margin-bottom: 8px;
    overflow-wrap: break-word;
    word-wrap: break-word;
    word-break: break-word;
    line-height: 1.6;
}

.question-task code,
.question-panel-body code {
    background: var(--purple-light);
    color: var(--accent-purple);
    padding: 2px 7px;
    border-radius: 5px;
    font-size: 12.5px;
    font-family: 'JetBrains Mono', Consolas, monospace;
    font-weight: 600;
    white-space: normal;
    overflow-wrap: anywhere;
    word-break: break-word;
    display: inline;
    box-decoration-break: clone;
    -webkit-box-decoration-break: clone;
}

.question-task strong {
    color: var(--text-primary);
}

.question-skills-row {
    display: flex;
    gap: 5px;
    flex-wrap: wrap;
    margin-bottom: 4px;
}

.question-skill-tag {
    font-size: 10.5px;
    font-weight: 600;
    padding: 3px 9px;
    border-radius: 6px;
    background: #EEF2FF;
    color: #4F46E5;
    border: 1px solid rgba(79,70,229,0.15);
    font-family: 'JetBrains Mono', Consolas, monospace;
    overflow-wrap: anywhere;
    word-break: break-word;
}

/* Hints */
.question-hints {
    margin-bottom: 16px;
    overflow-wrap: break-word;
    word-wrap: break-word;
    word-break: break-word;
}

.hint-toggle-btn {
    background: transparent;
    border: 1px dashed var(--border-color);
    border-radius: 8px;
    padding: 8px 14px;
    font-size: 12.5px;
    font-weight: 600;
    color: var(--text-muted);
    cursor: pointer;
    width: 100%;
    text-align: left;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all 0.15s ease;
    overflow-wrap: break-word;
    word-break: break-word;
}

.hint-toggle-btn:hover {
    border-color: #FBBF24;
    color: #B45309;
    background: #FFFBEB;
}

.hints-list {
    display: none;
    list-style: none;
    padding: 0;
    margin: 8px 0 0 0;
}

.hints-list.is-visible { display: block; }

.hints-list li {
    font-size: 12.5px;
    color: var(--text-secondary);
    line-height: 1.6;
    padding: 8px 12px;
    background: #FFFBEB;
    border-left: 3px solid #FBBF24;
    border-radius: 0 6px 6px 0;
    margin-bottom: 6px;
    overflow-wrap: break-word;
    word-wrap: break-word;
    word-break: break-word;
    white-space: normal;
}

.hints-list li code {
    background: #FEF3C7;
    color: #92400E;
    padding: 1px 5px;
    border-radius: 3px;
    font-size: 11.5px;
    font-family: 'JetBrains Mono', Consolas, monospace;
    white-space: normal;
    overflow-wrap: anywhere;
    word-break: break-word;
    display: inline;
    box-decoration-break: clone;
    -webkit-box-decoration-break: clone;
}

/* Test Results in Question Panel */
.test-results-section {
    border-top: 1px solid var(--border-subtle);
    padding-top: 14px;
    overflow-wrap: break-word;
    word-break: break-word;
}

.test-results-section h4 {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-muted);
    margin: 0 0 10px 0;
}

.test-results-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.test-result-item,
.test-item {
    font-size: 12.5px;
    font-weight: 500;
    padding: 8px 12px;
    border-radius: 8px;
    display: flex;
    align-items: flex-start;
    gap: 8px;
    border: 1px solid var(--border-color);
    background: var(--bg-primary);
    color: var(--text-secondary);
    transition: all 0.2s ease;
    overflow-wrap: break-word;
    word-wrap: break-word;
    word-break: break-word;
    line-height: 1.5;
}

.test-result-item.pass,
.test-item.pass {
    background: #F0FDF4;
    border-color: #BBF7D0;
    color: #166534;
}

.test-result-item.fail,
.test-item.fail {
    background: #FEF2F2;
    border-color: #FECACA;
    color: #991B1B;
}

.test-result-icon,
.test-item .test-icon {
    font-size: 14px;
    flex-shrink: 0;
    margin-top: 1px;
}

.test-result-item .test-name,
.test-item .test-name {
    flex: 1;
    overflow-wrap: anywhere;
    word-break: break-word;
    white-space: normal;
}

.test-score-bar {
    margin-top: 10px;
    padding: 10px 14px;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    text-align: center;
    font-size: 13px;
    font-weight: 700;
    color: var(--text-primary);
}

.test-score-bar.all-pass {
    background: #F0FDF4;
    border-color: #86EFAC;
    color: #166534;
}

/* Center Panel — Editor */
.ide-panel-editor {
    flex: 1 1 0%;
    min-width: 260px;
    display: flex;
    flex-direction: column;
    border-radius: 14px;
    overflow: hidden;
    border: 1px solid #282838;
    background: #181825;
    box-shadow: 0 8px 30px rgba(0,0,0,0.18);
    box-sizing: border-box;
}

/* Editor Tab Bar */
.editor-tab-bar {
    display: flex;
    align-items: center;
    background: #11111B;
    padding: 0;
    gap: 0;
    border-bottom: 1px solid #282838;
}

.editor-tab {
    padding: 11px 22px;
    font-size: 12.5px;
    font-weight: 600;
    font-family: 'JetBrains Mono', Consolas, monospace;
    color: #7A7F98;
    background: transparent;
    border: none;
    border-bottom: 2.5px solid transparent;
    cursor: pointer;
    transition: all 0.15s ease;
    display: flex;
    align-items: center;
    gap: 7px;
    letter-spacing: 0.02em;
}

.editor-tab:hover {
    color: #CDD6F4;
    background: rgba(255,255,255,0.03);
}

.editor-tab.active {
    color: #F8FAFC;
    background: #181825;
    border-bottom-color: #6C4CE8;
    font-weight: 700;
}

.editor-tab .tab-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
}

.editor-tab .tab-dot.dot-html { background: #F97316; box-shadow: 0 0 8px rgba(249,115,22,0.4); }
.editor-tab .tab-dot.dot-css  { background: #38BDF8; box-shadow: 0 0 8px rgba(56,189,248,0.4); }
.editor-tab .tab-dot.dot-js   { background: #FBBF24; box-shadow: 0 0 8px rgba(251,191,36,0.4); }

/* Editor Actions Bar */
.editor-actions-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 14px;
    background: #181825;
    border-bottom: 1px solid #282838;
}

.editor-actions-left {
    display: flex;
    gap: 8px;
}

.editor-run-btn {
    background: linear-gradient(135deg, #10B981, #059669);
    color: #FFFFFF;
    border: none;
    border-radius: 7px;
    padding: 7px 20px;
    font-size: 12.5px;
    font-weight: 700;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all 0.15s ease;
    font-family: inherit;
    box-shadow: 0 2px 8px rgba(16,185,129,0.3);
}

.editor-run-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 14px rgba(16,185,129,0.45);
}

.editor-reset-btn {
    background: rgba(255,255,255,0.06);
    color: #A6ADC8;
    border: 1px solid #2D2D3F;
    border-radius: 7px;
    padding: 7px 14px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
    font-family: inherit;
}

.editor-reset-btn:hover {
    background: rgba(255,255,255,0.12);
    color: #F8FAFC;
    border-color: #45475A;
}

.editor-actions-right {
    display: flex;
    gap: 8px;
}

.editor-answer-btn {
    background: rgba(251,191,36,0.08);
    color: #FBBF24;
    border: 1px solid rgba(251,191,36,0.25);
    border-radius: 7px;
    padding: 7px 14px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
    font-family: inherit;
}

.editor-answer-btn:hover {
    color: #FDE68A;
    border-color: #FBBF24;
    background: rgba(251,191,36,0.15);
}

.editor-answer-btn.is-revealed {
    color: #F43F5E;
    border-color: #F43F5E;
    background: rgba(244,63,94,0.1);
}

/* Editor Body */
.editor-body {
    background: #181825;
    flex: 1 1 0%;
    display: flex;
    flex-direction: column;
    min-height: 350px;
    position: relative;
    overflow: hidden;
}

.editor-textarea-wrapper {
    flex: 1 1 0%;
    min-height: 0;
    display: none; /* shown via JS */
    position: relative;
    background: #181825;
    overflow: hidden;
}

.editor-textarea-wrapper.active {
    display: flex;
}

/* Line Numbers Gutter */
.editor-line-numbers {
    width: 44px;
    padding: 14px 10px 14px 0;
    text-align: right;
    background: #181825;
    color: #4B526D;
    font-family: 'JetBrains Mono', Consolas, monospace;
    font-size: 13px;
    line-height: 1.65;
    user-select: none;
    border-right: 1px solid #282838;
    overflow: hidden;
    flex-shrink: 0;
    box-sizing: border-box;
}

/* Code Container (Overlaying Highlight Layer and Transparent Textarea) */
.editor-code-container {
    position: relative;
    flex: 1;
    display: flex;
    overflow: hidden;
    background: #181825;
}

.editor-highlight-layer {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 14px 16px;
    font-family: 'JetBrains Mono', Consolas, monospace;
    font-size: 13px;
    line-height: 1.65;
    white-space: pre;
    pointer-events: none;
    overflow: hidden;
    box-sizing: border-box;
    tab-size: 4;
    -moz-tab-size: 4;
    border: none;
    background: transparent;
    z-index: 1;
}

.editor-highlight-layer code {
    font-family: inherit;
    font-size: inherit;
    line-height: inherit;
    color: #CDD6F4;
    background: transparent;
    padding: 0;
    border: none;
}

.editor-textarea {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 14px 16px;
    font-family: 'JetBrains Mono', Consolas, monospace;
    font-size: 13px;
    line-height: 1.65;
    white-space: pre;
    overflow: auto;
    box-sizing: border-box;
    tab-size: 4;
    -moz-tab-size: 4;
    border: none;
    outline: none;
    resize: none;
    background: transparent;
    color: transparent;
    caret-color: #F8FAFC;
    z-index: 2;
    -webkit-text-fill-color: transparent;
}

.editor-textarea::placeholder {
    color: #4B526D;
    -webkit-text-fill-color: #4B526D;
}

.editor-textarea::selection {
    background: rgba(108, 76, 232, 0.45);
    color: transparent;
    -webkit-text-fill-color: transparent;
}

/* ==========================================================================
   SYNTAX HIGHLIGHTING TOKENS (Unified VS Code Dark+ IDE Theme)
   ========================================================================== */
.hl-kw, .tok-kw, .tok-keyword          { color: #C084FC !important; font-weight: 600 !important; }
.hl-fn, .tok-fn, .tok-method           { color: #FCD34D !important; font-weight: 600 !important; }
.hl-tag, .tok-tag                      { color: #38BDF8 !important; font-weight: 600 !important; }
.hl-builtin, .tok-sel, .tok-builtin     { color: #38BDF8 !important; font-weight: 600 !important; }
.hl-attr, .tok-attr                    { color: #9CDCFE !important; }
.hl-prop, .tok-prop, .tok-property     { color: #7DD3FC !important; }
.hl-var, .tok-var                      { color: #9CDCFE !important; }
.hl-str, .hl-string, .tok-str, .tok-string { color: #FB923C !important; }
.hl-num, .tok-num, .tok-number, .hl-val, .tok-val { color: #A3E635 !important; font-weight: 600 !important; }
.hl-atom, .tok-atom                    { color: #A3E635 !important; font-weight: 600 !important; }
.hl-cm, .hl-cmt, .tok-cm, .tok-comment { color: #7EC770 !important; font-style: italic !important; }
.hl-doctype                            { color: #C084FC !important; font-weight: 700 !important; }
.hl-op, .tok-op                        { color: #F8FAFC !important; }
.hl-punct, .tok-punct, .tok-punc       { color: #F8FAFC !important; }
.hl-plain                              { color: #F8FAFC !important; }

/* Console Output Panel */
.editor-console {
    background: #11111B;
    border-top: 1px solid #282838;
    min-height: 90px;
    max-height: 170px;
    overflow-y: auto;
}

.console-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 7px 14px;
    background: #14141E;
    border-bottom: 1px solid #242432;
}

.console-header span {
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: #7A7F98;
    display: flex;
    align-items: center;
    gap: 6px;
}

.console-body {
    padding: 10px 14px;
    font-family: 'JetBrains Mono', Consolas, monospace;
    font-size: 12px;
    line-height: 1.6;
    color: #A6ADC8;
    white-space: pre-wrap;
    word-break: break-word;
}

.console-body .log-success { color: #A6E3A1; }
.console-body .log-error   { color: #F38BA8; }
.console-body .log-info    { color: #89B4FA; }
.console-body .log-warn    { color: #F9E2AF; }

/* Right Panel — Preview */
.ide-panel-preview {
    width: 380px;
    min-width: 220px;
    max-width: 750px;
    flex-shrink: 0;
    background: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 14px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-subtle);
    box-sizing: border-box;
}

.preview-header {
    display: flex;
    align-items: center;
    padding: 10px 16px;
    background: #F8FAFC;
    border-bottom: 1px solid var(--border-color);
    gap: 8px;
}

.preview-dots {
    display: flex;
    gap: 5px;
}

.preview-dots span {
    width: 10px; height: 10px;
    border-radius: 50%;
}

.preview-dots span:nth-child(1) { background: #F38BA8; }
.preview-dots span:nth-child(2) { background: #F9E2AF; }
.preview-dots span:nth-child(3) { background: #A6E3A1; }

.preview-header .preview-url {
    flex: 1;
    background: #FFFFFF;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 4px 12px;
    font-size: 11.5px;
    font-family: 'JetBrains Mono', Consolas, monospace;
    color: var(--text-muted);
}

.preview-iframe-wrapper {
    flex: 1;
    min-height: 400px;
    position: relative;
}

.preview-iframe-wrapper iframe {
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0; left: 0;
    border: none;
    background: #FFFFFF;
}

.preview-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    min-height: 400px;
    color: var(--text-muted);
    font-size: 14px;
    gap: 8px;
}

.preview-placeholder .placeholder-icon {
    font-size: 40px;
    opacity: 0.4;
}

/* Answer Overlay */
.answer-overlay {
    display: none;
    background: #0D1117;
    border-top: 2px solid #6C4CE8;
    height: 240px;
    min-height: 120px;
    max-height: 90%;
    position: relative;
    box-shadow: 0 -6px 20px rgba(0, 0, 0, 0.4);
    z-index: 10;
    flex-shrink: 0;
    box-sizing: border-box;
}

.answer-overlay.is-visible { 
    display: flex;
    flex-direction: column;
}

/* Horizontal Resizer Bar for Answer Panel */
.answer-resizer {
    height: 12px;
    cursor: row-resize;
    position: absolute;
    top: -6px;
    left: 0;
    right: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    z-index: 15;
    user-select: none;
    touch-action: none;
}

.answer-resizer:hover .resizer-handle-h,
.answer-resizer.is-dragging .resizer-handle-h {
    background: #6C4CE8;
    box-shadow: 0 0 10px rgba(108, 76, 232, 0.8);
    transform: scaleY(1.5);
}

.resizer-handle-h {
    width: 48px;
    height: 4px;
    background: #484F58;
    border-radius: 9999px;
    transition: all 0.15s ease;
}

.answer-overlay-top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    padding: 10px 16px 8px 16px;
    border-bottom: 1px solid #21262D;
    flex-wrap: wrap;
    flex-shrink: 0;
}

.answer-overlay-title {
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: #FBBF24;
}

.answer-overlay-tabs {
    display: flex;
    gap: 6px;
}

.answer-tab-btn {
    background: #161B22;
    color: #8B949E;
    border: 1px solid #30363D;
    border-radius: 6px;
    padding: 4px 10px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
}

.answer-tab-btn:hover {
    color: #F0F6FC;
    border-color: #6C4CE8;
    background: #21262D;
}

.answer-tab-btn.active {
    background: #6C4CE8;
    color: white;
    border-color: #6C4CE8;
}

.answer-copy-btn {
    background: #21262D;
    color: #C9D1D9;
    border: 1px solid #30363D;
    border-radius: 6px;
    padding: 4px 10px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
    margin-left: auto;
}

.answer-copy-btn:hover {
    background: #30363D;
    color: white;
}

.answer-copy-btn.is-copied {
    background: #238636;
    color: white;
    border-color: #2ea043;
}

.answer-overlay pre {
    margin: 0;
    padding: 12px 16px;
    background: transparent;
    border: none;
    overflow: auto;
    flex: 1;
}

.answer-overlay code {
    font-family: 'JetBrains Mono', Consolas, monospace;
    font-size: 12.5px;
    line-height: 1.6;
    color: #F8FAFC;
    white-space: pre;
}


/* ==========================================================================
   3. DARK THEME OVERRIDES
   ========================================================================== */

[data-theme="dark"] .practice-hub-hero {
    background: linear-gradient(135deg, #1A0A1C 0%, #0D090F 50%, #0A0D10 100%);
    border-color: #3A163A;
}

[data-theme="dark"] .practice-hub-hero .hub-eyebrow {
    background: rgba(26,10,28,0.9);
    border-color: #3A163A;
}

[data-theme="dark"] .practice-level-card {
    background: #0D090F;
    border-color: #3A163A;
}

[data-theme="dark"] .practice-level-card:hover {
    box-shadow: var(--shadow-hover);
}

[data-theme="dark"] .level-card-number {
    background: linear-gradient(135deg, #1A0A1C, #250E28);
    border-color: #3A163A;
}

[data-theme="dark"] .level-skill-chip {
    background: #120B14;
    border-color: #3A163A;
    color: #918A96;
}

[data-theme="dark"] .level-progress-bar {
    background: #1E0D1E;
}

[data-theme="dark"] .level-progress-fill {
    background: linear-gradient(90deg, #D946EF, #A855F7);
}

[data-theme="dark"] .level-card-stars .star-empty { color: #3A163A; }

[data-theme="dark"] .level-card-footer {
    border-color: #1E0D1E;
}

[data-theme="dark"] .ide-panel-question {
    background: #0D090F;
    border-color: #3A163A;
}

[data-theme="dark"] .question-panel-header {
    background: #0D090F;
    border-color: #1E0D1E;
}

[data-theme="dark"] .question-task code {
    background: #1A0A1C;
    color: #D946EF;
}

[data-theme="dark"] .question-skill-tag {
    background: #1A0A1C;
    color: #D946EF;
    border-color: #3A163A;
}

[data-theme="dark"] .hints-list li {
    background: #1A1000;
    border-left-color: #FBBF24;
    color: #C4BFC8;
}

[data-theme="dark"] .hints-list li code {
    background: #281800;
    color: #FBBF24;
}

[data-theme="dark"] .hint-toggle-btn {
    border-color: #3A163A;
    color: #918A96;
}

[data-theme="dark"] .hint-toggle-btn:hover {
    background: #1A1000;
    border-color: #FBBF24;
    color: #FBBF24;
}

[data-theme="dark"] .test-result-item {
    border-color: #3A163A;
    background: #120B14;
    color: #918A96;
}

[data-theme="dark"] .test-result-item.pass {
    background: #051A10;
    border-color: #0D3520;
    color: #34D399;
}

[data-theme="dark"] .test-result-item.fail {
    background: #1A0505;
    border-color: #3A0D0D;
    color: #F87171;
}

[data-theme="dark"] .test-score-bar {
    background: #120B14;
    border-color: #3A163A;
}

[data-theme="dark"] .test-score-bar.all-pass {
    background: #051A10;
    border-color: #0D3520;
    color: #34D399;
}

[data-theme="dark"] .ide-panel-preview {
    background: #0D090F;
    border-color: #3A163A;
}

[data-theme="dark"] .preview-header {
    background: #120B14;
    border-color: #3A163A;
}

[data-theme="dark"] .preview-header .preview-url {
    background: #0D090F;
    border-color: #3A163A;
    color: #918A96;
}

[data-theme="dark"] .preview-iframe-wrapper iframe {
    background: #0D090F;
}

[data-theme="dark"] .ide-back-btn {
    background: #0D090F;
    border-color: #3A163A;
    color: #C4BFC8;
}

[data-theme="dark"] .ide-back-btn:hover {
    background: #1A0A1C;
    color: #D946EF;
    border-color: #D946EF;
}

[data-theme="dark"] .ide-nav-btn,
[data-theme="dark"] .ide-action-btn {
    background: #0D090F;
    border-color: #3A163A;
    color: #918A96;
}

[data-theme="dark"] .ide-nav-btn:hover,
[data-theme="dark"] .ide-action-btn:hover {
    background: #1A0A1C;
    color: #D946EF;
    border-color: #D946EF;
}

[data-theme="dark"] .ide-maximize-btn.is-active {
    background: linear-gradient(135deg, #D946EF, #A855F7);
    color: #FFFFFF;
    border-color: transparent;
    box-shadow: 0 2px 10px rgba(217, 70, 239, 0.35);
}

[data-theme="dark"] .ide-resizer .resizer-handle {
    background: #3A163A;
}

[data-theme="dark"] .ide-resizer:hover .resizer-handle,
[data-theme="dark"] .ide-resizer.is-dragging .resizer-handle {
    background: #D946EF;
    box-shadow: 0 0 10px rgba(217, 70, 239, 0.5);
}

[data-theme="dark"] .ide-resizer:hover,
[data-theme="dark"] .ide-resizer.is-dragging {
    background: rgba(217, 70, 239, 0.12);
}

[data-theme="dark"] .ide-question-badge {
    background: #1A0A1C;
    border-color: #3A163A;
    color: #D946EF;
}

[data-theme="dark"] .practice-strategy-banner {
    background: linear-gradient(135deg, #120B14 0%, #1A0A1C 100%);
}

[data-theme="dark"] .strategy-step {
    background: rgba(255,255,255,0.04);
    border-color: rgba(255,255,255,0.06);
}

[data-theme="dark"] .strategy-step .step-num {
    background: linear-gradient(135deg, #D946EF, #A855F7);
}

[data-theme="dark"] .levels-section-header .section-badge {
    background: #1A0A1C;
    border-color: #3A163A;
    color: #D946EF;
}

[data-theme="dark"] .level-start-btn {
    background: #D946EF;
}

[data-theme="dark"] .level-start-btn:hover {
    background: #F0ABFC;
}

[data-theme="dark"] .editor-run-btn {
    background: linear-gradient(135deg, #34D399, #10B981);
}