/* ==========================================================================
   glosings0n Codelabs Design System
   Subdomain: codelabs.glosings0n.dev
   Fonts: 'Figtree' (UI), 'JetBrains Mono' (Code, Digits, Metrics),
          'Urbanist' (LosingTek brand)
   Themes: Signature glosings0n Dark Mode + High-Contrast Projector Light Mode
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Figtree:ital,wght@0,300..900;1,300..900&family=JetBrains+Mono:ital,wght@0,300..800;1,300..800&family=Urbanist:ital,wght@0,400;0,700;1,400;1,700&display=swap');

@font-face {
    font-family: 'JetBrainsMonoDigits';
    font-style: normal;
    font-weight: 300 900;
    font-display: swap;
    src: local('JetBrains Mono'), local('JetBrainsMono-Regular'),
         url('https://fonts.gstatic.com/s/jetbrainsmono/v24/tDbY2o-flEEny0FZhsfKu5WU4zr3E_BX0PnT8RD8yKxjPQ.ttf') format('truetype');
    unicode-range: U+0030-0039, U+002B;
}

/* 1. Theme Tokens (Default: Dark Mode matching glosings0n.dev) */
:root,
[data-theme="dark"] {
    --bg-primary: #070a13;
    --bg-secondary: #0f1424;
    --bg-tertiary: #171d32;
    --bg-elevated: #1c243d;
    --bg-code: #0b0f1d;
    --bg-code-header: #131a2e;
    --border-color: #202b46;
    --border-subtle: #182036;

    --color-cyan: #00B0FF;
    --color-cyan-tint: rgba(0, 176, 255, 0.12);
    --color-blue: #02569B;
    --color-blue-light: #40c4ff;
    --color-green: #10b981;
    --color-green-bg: rgba(16, 185, 129, 0.12);
    --color-amber: #f59e0b;
    --color-amber-bg: rgba(245, 158, 11, 0.12);
    --color-red: #ef4444;
    --color-red-bg: rgba(239, 68, 68, 0.12);

    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    --text-on-accent: #040711;

    --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.25);
    --shadow-md: 0 12px 32px rgba(0, 0, 0, 0.4);
    --logo-filter: invert(56%) sepia(87%) saturate(2250%) hue-rotate(172deg) brightness(101%) contrast(106%);
}

/* Light Mode (High-Contrast Google Codelab / Projector Friendly) */
[data-theme="light"] {
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f1f5f9;
    --bg-elevated: #e2e8f0;
    --bg-code: #0f172a;
    --bg-code-header: #1e293b;
    --border-color: #cbd5e1;
    --border-subtle: #e2e8f0;

    --color-cyan: #0284c7;
    --color-cyan-tint: rgba(2, 132, 199, 0.1);
    --color-blue: #02569B;
    --color-blue-light: #0369a1;
    --color-green: #059669;
    --color-green-bg: rgba(5, 150, 105, 0.1);
    --color-amber: #d97706;
    --color-amber-bg: rgba(217, 119, 6, 0.1);
    --color-red: #dc2626;
    --color-red-bg: rgba(220, 38, 38, 0.09);

    --text-primary: #0f172a;
    --text-secondary: #334155;
    --text-muted: #64748b;
    --text-on-accent: #ffffff;

    --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.06);
    --shadow-md: 0 10px 25px rgba(15, 23, 42, 0.08);
    --logo-filter: invert(32%) sepia(93%) saturate(1638%) hue-rotate(179deg) brightness(93%) contrast(98%);
}

:root {
    --font-family: 'JetBrainsMonoDigits', 'Figtree', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    --header-height: 64px;
    --sidebar-width: 300px;
    --border-radius: 12px;
    --transition-smooth: all 0.25s cubic-bezier(0.25, 0.8, 0.25, 1);
}

/* 2. Reset, Base & Ultra-Thin App-Themed Scrollbars */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

@supports not selector(::-webkit-scrollbar) {
    * {
        scrollbar-width: thin;
        scrollbar-color: var(--border-color) transparent;
    }
}

*::-webkit-scrollbar {
    width: 5px;
    height: 5px;
}

*::-webkit-scrollbar-button {
    display: none;
    width: 0;
    height: 0;
}

*::-webkit-scrollbar-track {
    background: transparent;
}

*::-webkit-scrollbar-thumb {
    background-color: var(--border-color);
    border-radius: 999px;
    transition: background-color 0.2s ease;
}

*::-webkit-scrollbar-thumb:hover {
    background-color: var(--color-cyan);
}

*::-webkit-scrollbar-corner {
    background: transparent;
}

html,
body {
    width: 100%;
    max-width: 100vw;
    overflow-x: hidden;
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-family: var(--font-family);
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
    transition: background-color 0.25s ease, color 0.25s ease;
    min-height: 100vh;
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
}

code, pre, kbd, samp, .font-mono {
    font-family: var(--font-mono);
}

.losingtek-font {
    font-family: 'Urbanist', sans-serif;
    font-weight: 400;
}

.losingtek-font .brand-bold {
    font-weight: 700;
}

a {
    color: var(--color-cyan);
    text-decoration: none;
    transition: var(--transition-smooth);
    overflow-wrap: anywhere;
    word-break: break-word;
}

a:hover {
    text-decoration: underline;
}

/* Clean lowercase domain / URL link (no badge, no uppercase) */
.codelab-url-link {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 0.92rem;
    font-weight: 500;
    color: var(--color-cyan);
    text-transform: lowercase;
    letter-spacing: -0.2px;
    background: none;
    border: none;
    padding: 0;
    line-height: 1.4;
    overflow-wrap: anywhere;
    word-break: break-all;
}

.codelab-url-link:hover {
    color: var(--color-blue-light);
    text-decoration: underline;
}

/* 3. Top Codelab App Bar */
.codelab-topbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    width: 100%;
    height: var(--header-height);
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    display: flex;
    flex-direction: column;
    justify-content: center;
    box-shadow: var(--shadow-sm);
}

.topbar-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    height: 100%;
    gap: 12px;
    width: 100%;
    max-width: 100%;
}

.topbar-left {
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 0;
    flex: 1;
}

.sidebar-toggle-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 4px;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.sidebar-toggle-btn .bar {
    width: 22px;
    height: 2px;
    background-color: var(--text-primary);
    border-radius: 2px;
    transition: var(--transition-smooth);
}

.sidebar-toggle-btn.open .bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.sidebar-toggle-btn.open .bar:nth-child(2) {
    opacity: 0;
}

.sidebar-toggle-btn.open .bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

.brand-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 1.1rem;
    white-space: nowrap;
    flex-shrink: 0;
}

.brand-link:hover {
    text-decoration: none;
    color: var(--color-cyan);
}

.brand-logo {
    width: 26px;
    height: 26px;
    filter: var(--logo-filter);
    flex-shrink: 0;
}

.brand-text {
    font-family: var(--font-mono);
    letter-spacing: -0.5px;
}

.brand-subtext {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--color-cyan);
    text-transform: lowercase;
    flex-shrink: 0;
}

.topbar-divider {
    color: var(--border-color);
    font-size: 1.1rem;
    user-select: none;
    flex-shrink: 0;
}

.codelab-header-title {
    font-size: 0.92rem;
    font-weight: 600;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    min-width: 0;
}

.topbar-right {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-shrink: 0;
}

.time-pill {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    font-weight: 600;
    padding: 5px 10px;
    border-radius: 50px;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    white-space: nowrap;
}

.time-pill svg {
    width: 14px;
    height: 14px;
    color: var(--color-cyan);
    flex-shrink: 0;
}

.action-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    font-family: var(--font-family);
    font-size: 0.82rem;
    font-weight: 600;
    padding: 6px 11px;
    border-radius: 8px;
    cursor: pointer;
    transition: var(--transition-smooth);
    white-space: nowrap;
}

.action-btn.icon-only {
    width: 36px;
    height: 36px;
    padding: 0;
}

.action-btn.icon-only span {
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.action-btn:hover {
    border-color: var(--color-cyan);
    color: var(--color-cyan);
    text-decoration: none;
}

.action-btn svg {
    width: 17px;
    height: 17px;
    flex-shrink: 0;
}

/* Progress Bar along bottom of topbar */
.codelab-progress-track {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--border-subtle);
}

.codelab-progress-fill {
    height: 100%;
    width: 11%;
    background-color: var(--color-cyan);
    transition: width 0.3s ease;
}

/* 4. Main Codelab Layout (Sidebar + Step Viewport) */
body.codelab-page {
    height: 100vh;
    height: 100dvh;
    overflow: hidden;
}

.codelab-layout {
    display: flex;
    padding-top: var(--header-height);
    height: 100vh;
    height: 100dvh;
    width: 100%;
    max-width: 100vw;
    overflow: hidden;
}

/* Left Step Drawer */
.codelab-sidebar {
    width: var(--sidebar-width);
    position: fixed;
    top: var(--header-height);
    bottom: 0;
    left: 0;
    height: calc(100vh - var(--header-height));
    height: calc(100dvh - var(--header-height));
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    overflow: hidden;
    overscroll-behavior: contain;
    z-index: 900;
    display: flex;
    flex-direction: column;
    transition: transform 0.3s ease;
}

.step-nav-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 5px;
    flex: 1;
    overflow-y: auto;
    overscroll-behavior: contain;
    -webkit-overflow-scrolling: touch;
    padding: 18px 12px;
}

.step-nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 9px 10px;
    border-radius: 10px;
    cursor: pointer;
    color: var(--text-secondary);
    font-size: 0.86rem;
    font-weight: 500;
    border: 1px solid transparent;
    transition: var(--transition-smooth);
    user-select: none;
}

.step-nav-item:hover {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

.step-nav-item.active {
    background-color: var(--color-cyan-tint);
    border-color: var(--color-cyan);
    color: var(--text-primary);
    font-weight: 600;
}

.step-nav-item.completed .step-num {
    background-color: var(--color-cyan);
    color: var(--text-on-accent);
    border-color: var(--color-cyan);
}

.step-num {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-mono);
    font-size: 0.74rem;
    font-weight: 700;
    flex-shrink: 0;
    color: var(--text-secondary);
    transition: var(--transition-smooth);
}

.step-nav-item.active .step-num {
    background-color: var(--color-cyan);
    color: var(--text-on-accent);
    border-color: var(--color-cyan);
}

.step-nav-title {
    flex: 1;
    line-height: 1.3;
    min-width: 0;
}

.step-nav-time {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    color: var(--text-muted);
    flex-shrink: 0;
}

.sidebar-footer {
    flex-shrink: 0;
    padding: 14px 16px;
    border-top: 1px solid var(--border-color);
    background-color: var(--bg-secondary);
    font-size: 0.76rem;
    color: var(--text-muted);
    display: flex;
    flex-direction: column;
    gap: 6px;
    overflow-wrap: anywhere;
}

.sidebar-copyright {
    font-size: 0.68rem;
    color: var(--text-muted);
    opacity: 0.8;
    margin-top: 2px;
}

/* 5. Main Content Area (min-width: 0 prevents flex child overflow!) */
.codelab-main {
    flex: 1;
    min-width: 0;
    max-width: 100%;
    height: calc(100vh - var(--header-height));
    height: calc(100dvh - var(--header-height));
    overflow-y: auto;
    overscroll-behavior-y: contain;
    -webkit-overflow-scrolling: touch;
    margin-left: var(--sidebar-width);
    padding: 36px 24px;
    display: flex;
    justify-content: center;
    align-items: flex-start;
}

.codelab-content-wrapper {
    width: 100%;
    max-width: 860px;
    min-width: 0;
}

/* Step Panels */
.codelab-step {
    display: none;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 36px;
    box-shadow: var(--shadow-sm);
    margin-bottom: 0;
    width: 100%;
    max-width: 100%;
    min-width: 0;
    overflow: hidden;
    animation: fadeInStep 0.25s ease-out;
}

.codelab-step.active {
    display: block;
}

body.mode-all-steps .codelab-step {
    display: block;
}

@keyframes fadeInStep {
    from {
        opacity: 0;
        transform: translateY(6px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.step-header {
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 18px;
    margin-bottom: 24px;
}

.step-eyebrow {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    font-family: var(--font-mono);
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--color-cyan);
    margin-bottom: 8px;
}

.codelab-last-updated {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-family: var(--font-mono);
    font-size: 0.76rem;
    font-weight: 500;
    color: var(--text-muted);
}

.step-title {
    font-size: 1.85rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    color: var(--text-primary);
    line-height: 1.25;
    overflow-wrap: anywhere;
}

/* Typography inside Steps */
.codelab-step h3 {
    font-size: 1.28rem;
    font-weight: 600;
    margin: 28px 0 12px;
    color: var(--text-primary);
    line-height: 1.3;
    overflow-wrap: anywhere;
}

.codelab-step h4 {
    font-size: 1.05rem;
    font-weight: 600;
    margin: 20px 0 8px;
    color: var(--text-primary);
    overflow-wrap: anywhere;
}

.codelab-step p {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-bottom: 16px;
    overflow-wrap: anywhere;
    word-break: break-word;
}

.codelab-step ul,
.codelab-step ol {
    margin: 0 0 18px 20px;
    color: var(--text-secondary);
    font-size: 0.98rem;
}

.codelab-step li {
    margin-bottom: 8px;
    overflow-wrap: anywhere;
    word-break: break-word;
}

.codelab-step li strong {
    color: var(--text-primary);
}

/* Inline code */
.codelab-step p code,
.codelab-step li code,
.codelab-step td code,
.codelab-step h2 code,
.codelab-step h3 code,
.codelab-card p code {
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--color-cyan);
    padding: 1px 6px;
    border-radius: 5px;
    font-size: 0.86em;
    overflow-wrap: anywhere;
    word-break: break-word;
}

/* 6. Code Blocks with Copy Button */
.code-window {
    background-color: var(--bg-code);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    margin: 18px 0 24px;
    width: 100%;
    max-width: 100%;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.code-window-header {
    background-color: var(--bg-code-header);
    border-bottom: 1px solid #222d47;
    padding: 9px 14px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    width: 100%;
}

.code-window-meta {
    display: flex;
    align-items: center;
    gap: 8px;
    min-width: 0;
    flex: 1;
}

.window-dots {
    display: flex;
    gap: 5px;
    flex-shrink: 0;
}

.window-dot {
    width: 9px;
    height: 9px;
    border-radius: 50%;
}

.window-dot.red { background-color: #ff5f56; }
.window-dot.yellow { background-color: #ffbd2e; }
.window-dot.green { background-color: #27c93f; }

.code-filename {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    color: #cbd5e1;
    font-weight: 500;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    min-width: 0;
}

.code-lang-badge {
    font-family: var(--font-mono);
    font-size: 0.66rem;
    font-weight: 700;
    text-transform: uppercase;
    padding: 2px 6px;
    border-radius: 4px;
    background-color: rgba(0, 176, 255, 0.15);
    color: #40c4ff;
    letter-spacing: 0.4px;
    flex-shrink: 0;
}

.copy-code-btn {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    background-color: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.14);
    color: #f8fafc;
    font-family: var(--font-mono);
    font-size: 0.74rem;
    font-weight: 600;
    padding: 4px 9px;
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition-smooth);
    flex-shrink: 0;
}

.copy-code-btn:hover {
    background-color: rgba(0, 176, 255, 0.2);
    border-color: #00B0FF;
    color: #40c4ff;
}

.copy-code-btn.copied {
    background-color: rgba(16, 185, 129, 0.2);
    border-color: #10b981;
    color: #34d399;
}

.copy-code-btn svg {
    width: 13px;
    height: 13px;
}

.code-window pre {
    padding: 16px 18px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    font-size: 0.85rem;
    line-height: 1.55;
    color: #e2e8f0;
    tab-size: 2;
    width: 100%;
    max-width: 100%;
}

/* 7. Callout / Admonition Boxes */
.callout {
    border-radius: 12px;
    padding: 16px 18px;
    margin: 20px 0;
    border: 1px solid var(--border-color);
    background-color: var(--bg-tertiary);
    display: flex;
    gap: 12px;
    align-items: flex-start;
    width: 100%;
    max-width: 100%;
}

.callout-icon {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
    margin-top: 2px;
}

.callout-body {
    flex: 1;
    min-width: 0;
}

.callout-title {
    font-weight: 700;
    font-size: 0.94rem;
    color: var(--text-primary);
    margin-bottom: 4px;
    overflow-wrap: anywhere;
}

.callout-body p {
    margin-bottom: 0;
    font-size: 0.92rem;
    overflow-wrap: anywhere;
    word-break: break-word;
}

.callout.callout-info {
    border-color: rgba(0, 176, 255, 0.28);
    background-color: var(--color-cyan-tint);
}
.callout.callout-info .callout-icon { color: var(--color-cyan); }

.callout.callout-success {
    border-color: rgba(16, 185, 129, 0.28);
    background-color: var(--color-green-bg);
}
.callout.callout-success .callout-icon { color: var(--color-green); }

.callout.callout-warning {
    border-color: rgba(245, 158, 11, 0.28);
    background-color: var(--color-amber-bg);
}
.callout.callout-warning .callout-icon { color: var(--color-amber); }

.callout.callout-danger {
    border-color: rgba(239, 68, 68, 0.28);
    background-color: var(--color-red-bg);
}
.callout.callout-danger .callout-icon { color: var(--color-red); }

/* 8. Tables & Metrics Grid */
.table-responsive {
    width: 100%;
    max-width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    margin: 18px 0 24px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.codelab-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.92rem;
}

.codelab-table th,
.codelab-table td {
    padding: 11px 14px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.codelab-table th {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    font-weight: 600;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.4px;
}

.codelab-table tr:last-child td {
    border-bottom: none;
}

.codelab-table td {
    color: var(--text-secondary);
}

.metric-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 175px), 1fr));
    gap: 14px;
    margin: 20px 0;
    width: 100%;
}

.metric-card {
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 4px;
    min-width: 0;
}

.metric-value {
    font-family: var(--font-mono);
    font-size: 1.55rem;
    font-weight: 700;
    color: var(--color-cyan);
}

.metric-label {
    font-size: 0.84rem;
    color: var(--text-secondary);
    font-weight: 500;
    line-height: 1.35;
}

/* 9. Step Bottom Navigation (Prev / Next) */
.step-pagination {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 26px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
    gap: 12px;
    width: 100%;
}

.nav-step-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 11px 18px;
    border-radius: 10px;
    font-family: var(--font-family);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-smooth);
    border: 1px solid var(--border-color);
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    text-align: center;
}

.nav-step-btn:hover {
    border-color: var(--color-cyan);
    color: var(--color-cyan);
    transform: translateY(-1px);
    text-decoration: none;
}

.nav-step-btn.primary {
    background-color: var(--color-cyan);
    border-color: var(--color-cyan);
    color: var(--text-on-accent);
}

.nav-step-btn.primary:hover {
    background-color: var(--color-blue-light);
    border-color: var(--color-blue-light);
    color: var(--text-on-accent);
}

.nav-step-btn[disabled] {
    opacity: 0.4;
    pointer-events: none;
}

/* 10. Codelabs Hub / Catalog Page Styles (4 XL / 3 LG / 2 MD / 1 Mobile, Always Centered) */
.hub-container {
    width: 100%;
    max-width: 1340px;
    margin: 0 auto;
    padding: calc(var(--header-height) + 48px) 24px 48px;
    flex: 1;
}

.hub-hero {
    text-align: center;
    max-width: 720px;
    margin: 0 auto 44px;
}

.hub-title {
    font-size: clamp(1.85rem, 4.5vw, 3rem);
    font-weight: 700;
    letter-spacing: -0.8px;
    margin: 0 0 14px;
    line-height: 1.2;
}

.hub-subtitle {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.codelab-card-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: stretch;
    gap: 24px;
    width: 100%;
}

/* Default Large Screen (1024px - 1439px): 3 cards per row, centered when 1 or odd */
.codelab-card {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 28px;
    display: flex;
    flex-direction: column;
    gap: 14px;
    transition: var(--transition-smooth);
    box-shadow: var(--shadow-sm);
    flex: 0 1 calc((100% - 48px) / 3);
    width: 100%;
    max-width: 420px;
    min-width: 0;
}

/* Extra-Large Screen (>= 1440px): 4 cards per row, always centered */
@media (min-width: 1440px) {
    .hub-container {
        max-width: 1600px;
        padding-left: 32px;
        padding-right: 32px;
    }

    .codelab-card {
        flex: 0 1 calc((100% - 72px) / 4);
        max-width: 390px;
    }
}

/* Medium Screen (641px - 1023px): 2 cards per row, always centered */
@media (max-width: 1023px) and (min-width: 641px) {
    .codelab-card-grid {
        gap: 20px;
    }

    .codelab-card {
        flex: 0 1 calc((100% - 20px) / 2);
        max-width: 450px;
    }
}

.codelab-card:hover {
    border-color: var(--color-cyan);
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    text-decoration: none;
}

.card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.card-tag {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    font-weight: 600;
    padding: 3px 9px;
    border-radius: 50px;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--color-cyan);
}

.codelab-card h2 {
    font-size: 1.35rem;
    color: var(--text-primary);
    line-height: 1.32;
    overflow-wrap: anywhere;
}

.codelab-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    flex: 1;
    overflow-wrap: anywhere;
    word-break: break-word;
}

.card-footer {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    padding-top: 14px;
    border-top: 1px solid var(--border-color);
    font-size: 0.84rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.card-cta {
    color: var(--color-cyan);
    font-weight: 600;
    font-family: var(--font-family);
}

.hub-footer {
    background-color: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    padding: 20px 24px;
    width: 100%;
    margin-top: auto;
}

.hub-footer-container {
    max-width: 1340px;
    margin: 0 auto;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
}

.hub-copyright {
    font-size: 0.95rem;
    color: var(--text-muted);
    margin: 0;
}

/* ==========================================================================
   11. Mobile & Tablet Responsive Refinements (Compact, Clean, Zero Overflow)
   ========================================================================== */
@media (max-width: 960px) {
    .sidebar-toggle-btn {
        display: inline-flex;
    }

    .codelab-sidebar {
        transform: translateX(-100%);
        box-shadow: var(--shadow-md);
        width: min(290px, 84vw);
    }

    .codelab-sidebar.open {
        transform: translateX(0);
    }

    .codelab-main {
        margin-left: 0;
        padding: 20px 14px;
    }

    .codelab-step {
        padding: 24px 18px;
    }

    .codelab-header-title,
    .topbar-divider {
        display: none;
    }
}

@media (max-width: 640px) {
    :root {
        --header-height: 56px;
    }

    .topbar-inner {
        padding: 0 12px;
        gap: 8px;
    }

    .brand-link {
        font-size: 0.98rem;
        gap: 6px;
    }

    .brand-logo {
        width: 22px;
        height: 22px;
    }

    .brand-subtext {
        font-size: 0.76rem;
    }

    .topbar-right {
        gap: 6px;
    }

    .time-pill {
        padding: 4px 8px;
        font-size: 0.72rem;
    }

    .action-btn {
        padding: 5px 8px;
        font-size: 0.75rem;
        gap: 4px;
    }

    .action-btn.icon-only {
        width: 32px;
        height: 32px;
        padding: 0;
    }

    .action-btn svg {
        width: 15px;
        height: 15px;
    }

    /* Hub Mobile */
    .hub-container {
        padding: calc(var(--header-height) + 28px) 14px 28px;
    }

    .hub-footer {
        padding: 16px 24px;
    }

    .hub-hero {
        margin-bottom: 28px;
    }

    .codelab-url-link {
        font-size: 0.8rem;
    }

    .hub-title {
        font-size: 1.55rem;
        margin: 8px 0 10px;
    }

    .hub-subtitle {
        font-size: 0.9rem;
        line-height: 1.5;
    }

    .codelab-card-grid {
        gap: 16px;
    }

    .codelab-card {
        flex: 0 1 100%;
        max-width: 100%;
        padding: 18px 15px;
        border-radius: 12px;
        gap: 10px;
    }

    .card-tag {
        font-size: 0.66rem;
        padding: 2px 7px;
    }

    .codelab-card h2 {
        font-size: 1.12rem;
    }

    .codelab-card p {
        font-size: 0.86rem;
        line-height: 1.5;
    }

    .card-footer {
        font-size: 0.76rem;
        padding-top: 10px;
    }

    /* Codelab Steps Mobile */
    .codelab-main {
        padding: 12px 10px;
    }

    .codelab-step {
        padding: 16px 13px;
        border-radius: 12px;
        margin-bottom: 0;
    }

    .step-header {
        padding-bottom: 12px;
        margin-bottom: 16px;
    }

    .step-eyebrow {
        font-size: 0.68rem;
        margin-bottom: 6px;
    }

    .step-title {
        font-size: 1.25rem;
        letter-spacing: -0.3px;
        line-height: 1.3;
    }

    .codelab-step h3 {
        font-size: 1.04rem;
        margin: 20px 0 8px;
    }

    .codelab-step h4 {
        font-size: 0.94rem;
        margin: 16px 0 6px;
    }

    .codelab-step p {
        font-size: 0.88rem;
        line-height: 1.55;
        margin-bottom: 12px;
    }

    .codelab-step ul,
    .codelab-step ol {
        font-size: 0.87rem;
        line-height: 1.52;
        margin: 0 0 14px 16px;
    }

    .codelab-step li {
        margin-bottom: 6px;
    }

    /* Callouts Mobile */
    .callout {
        padding: 12px;
        gap: 10px;
        margin: 14px 0;
        border-radius: 10px;
    }

    .callout-icon {
        width: 17px;
        height: 17px;
    }

    .callout-title {
        font-size: 0.85rem;
    }

    .callout-body p {
        font-size: 0.82rem;
        line-height: 1.48;
    }

    /* Code Windows Mobile */
    .code-window {
        margin: 12px 0 16px;
        border-radius: 10px;
    }

    .code-window-header {
        padding: 7px 10px;
        gap: 6px;
    }

    .window-dots {
        display: none;
    }

    .code-filename {
        font-size: 0.7rem;
    }

    .code-lang-badge {
        font-size: 0.58rem;
        padding: 1px 5px;
    }

    .copy-code-btn {
        font-size: 0.68rem;
        padding: 3px 7px;
    }

    .code-window pre {
        padding: 11px 12px;
        font-size: 0.74rem;
        line-height: 1.48;
    }

    /* Metric Cards & Tables Mobile */
    .metric-cards {
        grid-template-columns: repeat(2, 1fr);
        gap: 8px;
        margin: 14px 0;
    }

    .metric-card {
        padding: 11px 10px;
        border-radius: 10px;
    }

    .metric-value {
        font-size: 1.15rem;
    }

    .metric-label {
        font-size: 0.72rem;
    }

    .codelab-table {
        font-size: 0.78rem;
    }

    .codelab-table th,
    .codelab-table td {
        padding: 8px 9px;
    }

    .codelab-table th {
        font-size: 0.7rem;
    }

    /* Step Pagination Mobile */
    .step-pagination {
        flex-direction: column-reverse;
        align-items: stretch;
        gap: 8px;
        margin-top: 18px;
        padding-top: 14px;
    }

    .nav-step-btn {
        padding: 9px 14px;
        font-size: 0.84rem;
        width: 100%;
    }
}

@media (max-width: 380px) {
    .time-pill {
        display: none;
    }

    .metric-cards {
        grid-template-columns: 1fr;
    }
}