:root {
    --bg: #23133a;
    --surface: #23133a;
    --surface2: #1f1232;
    --border: #3a1c63;
    --border2: #5e309d;
    --accent: #883CF0;
    --accent2: #883CF0;
    --accent-dim: #873cf0d6;
    --accent-glow: #873cf0d6;
    --green: #00e5a0;
    --amber: #ffb340;
    --red: #ff4d6a;
    --text: #c8d6e5;
    --text-muted: #d6d6d6;
    --text-dim: #d6d6d6;
  }

  * { box-sizing: border-box; margin: 0; padding: 0; }
  html { scroll-behavior: smooth; }

  .dcm-training-guide {
    background: #191127;
    color: var(--text);
    font-size: 15px;
    line-height: 1.7;
    display: flex;
    min-height: 100vh;
    overflow-x: hidden;
  }

  /* ---- SIDEBAR ---- */
  #sidebar {
    width: 268px;
    min-width: 268px;
    background: #180f26;
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    position: sticky;
    top: 0; left: 0; bottom: 0;
    z-index: 1;
    overflow-y: auto;
  }

  .sidebar-logo {
    padding: 28px 24px 20px;
    border-bottom: 1px solid var(--border);
  }

  .sidebar-logo .product-tag {
    font-size: 10px;
    color: var(--accent);
    text-transform: uppercase;
    margin-bottom: 6px;
  }

  .sidebar-logo h1 {
    
    font-size: 18px;
    font-weight: 800;
    color: #fff;
    line-height: 1.2;
  }

  .sidebar-logo h1 span { color: var(--accent); }

  .progress-bar-wrap {
    padding: 16px 24px 20px;
    border-bottom: 1px solid var(--border);
  }

  .progress-label {
    display: flex;
    justify-content: space-between;
    font-size: 10px;
    color: var(--text-muted);
    margin-bottom: 8px;
  }

  #progress-pct { color: var(--accent); }

  .progress-track {
    height: 3px;
    background: #282035;
    border-radius: 2px;
    overflow: hidden;
  }

  .progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent2), var(--accent));
    border-radius: 2px;
    transition: width 0.4s ease;
    width: 0%;
  }

  .nav-section-label {
    font-size: 9.5px;
    color: var(--text-dim);
    text-transform: uppercase;
    padding: 18px 24px 8px;
  }

  .nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 24px;
    cursor: pointer;
    transition: all 0.15s;
    border-left: 2px solid transparent;
    font-size: 13.5px;
    color: var(--text-muted);
    user-select: none;
  }

  .nav-item:hover { color: var(--text); background: #23133a9f; }
  .nav-item.active {
    color: var(--accent);
    border-left-color: var(--accent);
    background: #23133a;
  }

  .nav-item .nav-num {
    
    font-size: 10px;
    color: var(--text-dim);
    min-width: 18px;
  }

  .nav-item.active .nav-num { color: var(--accent); }

  .nav-item .nav-check {
    margin-left: auto;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    border: 1.5px solid var(--border2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 8px;
    transition: all 0.2s;
  }

  .nav-item.done .nav-check {
    background: var(--green);
    border-color: var(--green);
    color: #000;
  }

  .sidebar-footer {
    margin-top: auto;
    padding: 18px 24px;
    border-top: 1px solid var(--border);
    
    font-size: 10px;
    color: var(--text-dim);
  }

  /* ---- MAIN ---- */
  #main {
    /* margin-left: 268px; */
    flex: 1;
    height: 100vh;
    overflow-y: auto;
  }

  /* ---- TOPBAR ---- */
  .topbar {
    position: sticky;
    top: 0;
    background: #191127;
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    padding: 14px 48px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    z-index: 1;
  }

  .breadcrumb {
    font-size: 11px;
    color: var(--text-muted);
  }

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

  .topbar-badge {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 10.5px;
    color: var(--accent);
  }

  .badge-dot {
    width: 7px; height: 7px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 8px var(--accent-dim);
    animation: pulse 2s infinite;
  }

  @keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
  }

  /* ---- CONTENT SECTIONS ---- */
  .section {
    display: none;
    padding: 52px 56px 80px;
    /* max-width: 900px; */
    animation: fadeSlide 0.35s ease;
  }

  .section.active { display: block; }

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

  .section-eyebrow {
    font-size: 10px;
    color: var(--accent);
    text-transform: uppercase;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 8px;
  }

  .section-eyebrow::before {
    content: '';
    display: block;
    width: 24px;
    height: 1.5px;
    background: var(--accent);
  }

  h2 {
    
    font-size: 36px;
    font-weight: 800;
    color: #fff;
    line-height: 1.15;
    margin-bottom: 10px;
  }

  h2 em {
    font-style: normal;
    color: var(--accent);
  }

  .section-intro {
    font-size: 16px;
    color: #c8d6e5;
    line-height: 1.75;
    margin-bottom: 40px;
    max-width: 680px;
    font-weight: 300;
  }

  h3 {
    
    font-size: 18px;
    font-weight: 700;
    color: #fff;
    margin: 36px 0 14px;
  }

  p { color: #c8d6e5; margin-bottom: 16px; line-height: 1.75; }

  /* ---- CARDS ---- */
  .card {
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 24px 28px;
    margin-bottom: 16px;
    transition: border-color 0.2s;
  }

  .card:hover { border-color: var(--border2); }

  .card.accent-card {
    border-color: #3a1c63;
    background: linear-gradient(135deg, #23133a, #2a1647);
  }

  /* ---- FLOW DIAGRAM ---- */
  .flow-diagram {
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 36px;
    margin: 28px 0;
    overflow-x: auto;
  }

  .flow-steps {
    display: flex;
    align-items: flex-start;
    gap: 0;
    min-width: 600px;
    position: relative;
  }

  .flow-step {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
    cursor: pointer;
  }

  .flow-step:not(:last-child)::after {
    content: '';
    position: absolute;
    top: 28px;
    right: -2px;
    width: calc(50% + 2px);
    left: 50%;
    height: 2px;
    background: linear-gradient(90deg, var(--border2), var(--border));
    z-index: 1;
  }

  .flow-step:not(:first-child)::before {
    content: '';
    position: absolute;
    top: 28px;
    left: -2px;
    right: 50%;
    height: 2px;
    background: linear-gradient(90deg, var(--border), var(--border2));
    z-index: 1;
  }

  .flow-icon-wrap {
    width: 56px; height: 56px;
    border-radius: 50%;
    background: var(--surface);
    border: 2px solid var(--border2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    margin-bottom: 12px;
    position: relative;
    z-index: 1;
    transition: all 0.2s;
  }

  .flow-step:hover .flow-icon-wrap,
  .flow-step.active .flow-icon-wrap {
    border-color: var(--accent);
    background: #3a1c6350;
    box-shadow: 0 0 20px #be52e50f;
  }

  .flow-step-label {
    font-size: 12px;
    font-weight: 700;
    color: var(--text-muted);
    text-align: center;
    max-width: 90px;
    line-height: 1.3;
    transition: color 0.2s;
  }

  .flow-step:hover .flow-step-label,
  .flow-step.active .flow-step-label { color: var(--accent); }

  .flow-detail {
    background: #5e309d14;
    border: 1px solid #3a1c63;
    border-radius: 8px;
    padding: 16px 20px;
    margin-top: 20px;
    font-size: 13.5px;
    color: #c8d6e5;
    display: none;
    animation: fadeSlide 0.2s ease;
  }

  .flow-detail.visible { display: block; }
  .flow-detail strong { color: var(--accent); font-weight: 500; }

  /* ---- BROWSER GRID ---- */
  .browser-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 14px;
    margin: 20px 0;
  }

  .browser-card {
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 20px 16px;
    text-align: center;
    transition: all 0.2s;
    cursor: default;
  }

  .browser-card:hover {
    border-color: var(--accent);
    background: var(--accent-dim);
    transform: translateY(-2px);
  }

  .browser-card .b-icon { font-size: 32px; margin-bottom: 8px; }

  .browser-card .b-name {
    
    font-size: 13px;
    font-weight: 700;
    color: var(--text);
  }

  .browser-card .b-status {
    
    font-size: 10px;
    color: var(--green);
    margin-top: 4px;
  }

  /* ---- STEPS LIST ---- */
  .steps-list { margin: 24px 0; }

  .step-item {
    display: flex;
    gap: 20px;
    margin-bottom: 12px;
    padding: 18px 20px;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.2s;
  }

  .step-item:hover {
    border-color: var(--border2);
    background: #2a1647
  }

  .step-num {
    width: 32px; height: 32px; min-width: 32px;
    border-radius: 50%;
    background: #1f1232;
    border: 1.5px solid #3a1c63;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: 600;
    color: var(--accent);
    margin-top: 2px;
  }

  .step-content h4 {
    
    font-size: 14.5px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 4px;
  }

  .step-content p {
    font-size: 13px;
    color: var(--text-muted);
    margin: 0;
  }

  /* ---- CALLOUT ---- */
  .callout {
    display: flex;
    gap: 14px;
    padding: 16px 20px;
    border-radius: 8px;
    margin: 20px 0;
    font-size: 13.5px;
    line-height: 1.6;
  }

  .callout.info {
    background: #23133a;
    border: 1px solid #3a1c63;
    color: #edf3f8;
  }

  .callout.warning {
    background: rgba(255,179,64,0.06);
    border: 1px solid rgba(255,179,64,0.2);
    color: #b89060;
  }

  .callout.success {
    background: rgba(0,229,160,0.06);
    border: 1px solid rgba(0,229,160,0.2);
    color: #5aaa8a;
  }

  .callout-icon { font-size: 18px; flex-shrink: 0; margin-top: 1px; }

  /* ---- CODE BLOCK ---- */
  .code-block {
    background: #040810;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 18px 20px;
    
    font-size: 12.5px;
    color: #ebf2f4;
    line-height: 1.8;
    margin: 16px 0;
    overflow-x: auto;
  }

  .code-block .c-comment { color: #a6a9ac; }
  .code-block .c-key { color: var(--accent); }
  .code-block .c-val { color: var(--green); }
  .code-block .c-label { color: var(--amber); }

  /* ---- TABS ---- */
  .tab-bar {
    display: flex;
    gap: 0;
    border-bottom: 1px solid var(--border);
    margin-bottom: 24px;
  }

  .tab-btn {
    padding: 10px 20px;
    font-size: 11px;
    color: var(--text-muted);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: all 0.15s;
    text-transform: uppercase;
    background: none;
    border-top: none;
    border-left: none;
    border-right: none;
  }

  .tab-btn:hover { color: var(--text); }
  .tab-btn.active { color: var(--accent); border-bottom-color: var(--accent); }

  .tab-pane { display: none; }
  .tab-pane.active { display: block; animation: fadeSlide 0.2s ease; }

  /* ---- SECURITY MODEL ---- */
  .security-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
    margin: 24px 0;
  }

  .sec-card {
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 22px;
    transition: all 0.2s;
  }

  .sec-card:hover { border-color: #5e309d; }

  .sec-card .sec-icon {
    font-size: 26px;
    margin-bottom: 12px;
  }

  .sec-card h4 {
    
    font-size: 14px;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 8px;
  }

  .sec-card p {
    font-size: 12.5px;
    color: var(--text-muted);
    margin: 0;
    line-height: 1.65;
  }

  /* ---- NEVER/ALWAYS COMPARISON ---- */
  .compare-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin: 24px 0;
  }

  .compare-col { border-radius: 10px; overflow: hidden; }

  .compare-header {
    padding: 12px 18px;
    
    font-size: 13px;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 8px;
  }

  .compare-col.no .compare-header {
    background: rgba(255,77,106,0.12);
    color: var(--red);
    border: 1px solid rgba(255,77,106,0.2);
    border-bottom: none;
  }

  .compare-col.yes .compare-header {
    background: rgba(0,229,160,0.1);
    color: var(--green);
    border: 1px solid rgba(0,229,160,0.2);
    border-bottom: none;
  }

  .compare-body {
    padding: 16px 18px;
    font-size: 13px;
    line-height: 1.7;
  }

  .compare-col.no .compare-body {
    background: rgba(255,77,106,0.04);
    border: 1px solid rgba(255,77,106,0.15);
    border-top: none;
    color: #b07080;
  }

  .compare-col.yes .compare-body {
    background: rgba(0,229,160,0.04);
    border: 1px solid rgba(0,229,160,0.15);
    border-top: none;
    color: #5aaa8a;
  }

  .compare-body li {
    margin-bottom: 6px;
    list-style: none;
    display: flex;
    align-items: flex-start;
    gap: 8px;
  }

  .compare-body li::before {
    font-size: 11px;
    margin-top: 3px;
    flex-shrink: 0;
  }

  .compare-col.no .compare-body li::before { content: '✕'; }
  .compare-col.yes .compare-body li::before { content: '✓'; }

  /* ---- QUIZ ---- */
  .quiz-card {
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 28px 30px;
    margin: 24px 0;
  }

  .quiz-q {
    
    font-size: 16px;
    font-weight: 700;
    color: #fff;
    margin-bottom: 20px;
    line-height: 1.4;
  }

  .quiz-q-num {
    font-size: 10px;
    color: var(--accent);
    margin-bottom: 8px;
  }

  .quiz-options { display: flex; flex-direction: column; gap: 10px; }

  .quiz-opt {
    padding: 12px 18px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 14px;
    color: var(--text-muted);
    cursor: pointer;
    transition: all 0.15s;
    display: flex;
    align-items: center;
    gap: 12px;
    user-select: none;
  }

  .quiz-opt:hover:not(.locked) { border-color: var(--border2); color: var(--text); }

  .quiz-opt .opt-letter {
    
    font-size: 11px;
    color: var(--text-dim);
    min-width: 16px;
  }

  .quiz-opt.correct {
    border-color: #77b255;
    background: #77b25520;
    color: #60c090;
  }

  .quiz-opt.wrong {
    border-color: #dc143c;
    background: #dc143c2b;
    color:#ff7a90;
  }

  .quiz-opt.locked { cursor: default; }

  .quiz-feedback {
    margin-top: 14px;
    padding: 12px 16px;
    border-radius: 8px;
    font-size: 13.5px;
    display: none;
    animation: fadeSlide 0.2s ease;
  }

  .quiz-feedback.show { display: block; }
  .quiz-feedback.ok { background: #77b25520;
    border: 1px solid #77b255;
    color: #60c090; }
  .quiz-feedback.bad { background: #dc143c2b;
    border: 1px solid #dc143c;
    color: #ff7a90; }

  /* ---- NEXT BUTTON ---- */
  .section-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 52px;
    padding-top: 28px;
    border-top: 1px solid var(--border);
  }

  .btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 11px 22px;
    border-radius: 8px;
    font-size: 13px;
    font-weight: 700;
    cursor: pointer;
    border: none;
    transition: all 0.15s;
  }

  .btn-primary {
    background: var(--accent);
    color: #000;
  }

  .btn-primary:hover { background: #883cf0e0; transform: translateX(2px); }

  .btn-ghost {
    background: transparent;
    color: var(--text-muted);
    border: 1px solid var(--border);
  }

  .btn-ghost:hover { border-color: var(--border2); color: var(--text); }

  .section-counter {
    
    font-size: 11px;
    color: var(--text-dim);
  }

  /* ---- UX DEMO ---- */
  .ux-demo {
    background: linear-gradient(135deg, #3a1c63, #7c4dbd);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 32px;
    margin: 24px 0;
    position: relative;
    overflow: hidden;
  }

  .ux-demo::before {
    content: '';
    position: absolute;
    top: -60px; right: -60px;
    width: 200px; height: 200px;
    border-radius: 50%;
    background: radial-gradient(circle, #23133a9f, transparent 70%);
    pointer-events: none;
  }

  .ux-screen {
    background: #23133a;
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid var(--border2);
    margin-bottom: 16px;
  }

  .ux-screen-bar {
    background: #23133a9f;
    padding: 9px 14px;
    display: flex;
    align-items: center;
    gap: 10px;
    border-bottom: 1px solid var(--border);
  }

  .ux-dots { display: flex; gap: 5px; }
  .ux-dot { width: 10px; height: 10px; border-radius: 50%; }
  .ux-dot:nth-child(1) { background: #ff5f57; }
  .ux-dot:nth-child(2) { background: #febc2e; }
  .ux-dot:nth-child(3) { background: #28c840; }

  .ux-url {
    flex: 1;
    background: #06101a;
    border-radius: 4px;
    padding: 4px 10px;
    
    font-size: 11px;
    color: var(--text-muted);
    margin: 0 10px;
  }

  .ux-ext-icon {
    font-size: 16px;
    cursor: pointer;
    transition: transform 0.15s;
  }

  .ux-ext-icon:hover { transform: scale(1.1); }

  .ux-screen-body {
    padding: 24px;
    min-height: 160px;
    position: relative;
  }

  .fake-login {
    max-width: 280px;
    margin: 0 auto;
  }

  .fake-login h5 {
    
    font-size: 16px;
    font-weight: 800;
    color: #fff;
    margin-bottom: 18px;
    text-align: center;
  }

  .fake-field {
    background: #06101a;
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 10px 14px;
    margin-bottom: 10px;
    
    font-size: 12px;
    color: var(--text-muted);
    position: relative;
    transition: border-color 0.2s;
  }

  .fake-field.has-val { border-color: rgba(0,229,160,0.4); color: var(--green); }

  .dcm-popup {
    position: absolute;
    right: 14px;
    top: 100%;
    margin-top: 8px;
    width: 230px;
    background: #0d1929;
    border: 1px solid #3a1c63;
    border-radius: 10px;
    padding: 14px;
    box-shadow: 0 12px 40px rgba(0,0,0,0.6);
    z-index: 1;
    display: none;
    animation: popIn 0.2s ease;
  }

  @keyframes popIn {
    from { opacity: 0; transform: scale(0.95) translateY(-4px); }
    to { opacity: 1; transform: scale(1) translateY(0); }
  }

  .dcm-popup.show { display: block; }

  .dcm-popup-head {
    font-size: 9px;
    color: var(--accent);
    text-transform: uppercase;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 6px;
  }

  .dcm-popup-head::before {
    content: '🔑';
    font-size: 12px;
  }

  .dcm-cred-item {
    background: #23133a;
    border: 1px solid #3a1c63;
    border-radius: 6px;
    padding: 8px 10px;
    cursor: pointer;
    margin-bottom: 6px;
    transition: all 0.15s;
  }

  .dcm-cred-item:hover { background: #1f1232; border-color: #5e309d; }

  .dcm-cred-name {
    
    font-size: 12px;
    font-weight: 700;
    color: #fff;
  }

  .dcm-cred-user {
    
    font-size: 10px;
    color: var(--text-muted);
    margin-top: 2px;
  }

  .demo-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    background: var(--accent);
    color: #000;
    border: none;
    border-radius: 6px;
    
    font-size: 12px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.15s;
    margin-top: 8px;
  }

  .demo-btn:hover { background: #883cf0e0; }

  .demo-status {
    
    font-size: 11px;
    color: var(--text-muted);
    margin-top: 10px;
    min-height: 18px;
  }

  /* ---- TAG ---- */
  .tag {
    display: inline-flex;
    align-items: center;
    padding: 2px 10px;
    border-radius: 20px;
    font-size: 10px;
    font-weight: 600;
    margin: 2px;
  }

  .tag-blue { background: #291a3e; color: var(--accent); border: 1px solid #3a1c63; }
  .tag-green { background: rgba(0,229,160,0.1); color: var(--green); border: 1px solid rgba(0,229,160,0.2); }
  .tag-amber { background: rgba(255,179,64,0.1); color: var(--amber); border: 1px solid rgba(255,179,64,0.2); }

  /* ---- HERO section ---- */
  .hero-meta {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-top: 28px;
    flex-wrap: wrap;
  }

  .hero-stat {
    display: flex;
    flex-direction: column;
    gap: 2px;
  }

  .hero-stat .stat-val {
    
    font-size: 22px;
    font-weight: 800;
    color: var(--accent);
    line-height: 1;
  }

  .hero-stat .stat-label {
    font-size: 9.5px;
    color: var(--text-dim);
    text-transform: uppercase;
  }

  .hero-divider {
    width: 1px;
    height: 36px;
    background: var(--border);
  }

  /* ---- Dividers ---- */
  hr {
    border: none;
    border-top: 1px solid var(--border);
    margin: 32px 0;
  }

  /* ---- GLOSSARY ---- */
  .gloss-item {
    padding: 14px 0;
    border-bottom: 1px solid var(--border);
    display: flex;
    gap: 20px;
  }

  .gloss-term {
    
    font-size: 12px;
    color: var(--accent);
    min-width: 160px;
    padding-top: 2px;
  }

  .gloss-def { font-size: 13.5px; color: var(--text-muted); line-height: 1.65; }

  /* scrollbar */
  ::-webkit-scrollbar { width: 6px; height: 6px; }
  ::-webkit-scrollbar-track { background: #873cf015; }
  ::-webkit-scrollbar-thumb { background: #873cf015; border-radius: 3px; }
  ::-webkit-scrollbar-thumb:hover { background: #873cf015; }

  @media (max-width: 900px) {
    #sidebar { display: none; }
    #main { margin-left: 0; }
    .section { padding: 32px 24px 60px; }
    .security-grid, .compare-grid { grid-template-columns: 1fr; }
    .topbar { padding: 12px 24px; }
  }