HLCRF Deep Dive

This guide provides an in-depth look at the HLCRF (Header-Left-Content-Right-Footer) layout system, covering all layout combinations, the ID system, responsive patterns, and complex real-world examples.

Layout Combinations

HLCRF supports any combination of its five regions. The variant name describes which regions are present.

All Possible Combinations

Variant	Regions	Use Case
`C`	Content only	Simple content pages
`HC`	Header + Content	Landing pages
`CF`	Content + Footer	Article pages
`HCF`	Header + Content + Footer	Standard pages
`LC`	Left + Content	App with navigation
`CR`	Content + Right	Content with sidebar
`LCR`	Left + Content + Right	Three-column layout
`HLC`	Header + Left + Content	Admin dashboard
`HCR`	Header + Content + Right	Blog with widgets
`LCF`	Left + Content + Footer	App with footer
`CRF`	Content + Right + Footer	Blog layout
`HLCF`	Header + Left + Content + Footer	Standard admin
`HCRF`	Header + Content + Right + Footer	Blog layout
`HLCR`	Header + Left + Content + Right	Full admin
`LCRF`	Left + Content + Right + Footer	Complex app
`HLCRF`	All five regions	Complete layout

Content-Only (C)

Minimal layout for simple content:

php

use Core\Front\Components\Layout;

$layout = Layout::make('C')
    ->c('<main>Simple content without chrome</main>');

echo $layout->render();

Output:

html

<div class="hlcrf-layout" data-layout="root">
    <div class="hlcrf-body flex flex-1">
        <main class="hlcrf-content flex-1" data-slot="C">
            <div data-block="C-0">
                <main>Simple content without chrome</main>
            </div>
        </main>
    </div>
</div>

Header + Content + Footer (HCF)

Standard page layout:

php

$layout = Layout::make('HCF')
    ->h('<nav>Site Navigation</nav>')
    ->c('<article>Page Content</article>')
    ->f('<footer>Copyright 2026</footer>');

Left + Content (LC)

Application with navigation sidebar:

php

$layout = Layout::make('LC')
    ->l('<nav class="w-64">App Menu</nav>')
    ->c('<main>App Content</main>');

Three-Column (LCR)

Full three-column layout:

php

$layout = Layout::make('LCR')
    ->l('<nav>Navigation</nav>')
    ->c('<main>Content</main>')
    ->r('<aside>Widgets</aside>');

Full Admin (HLCRF)

Complete admin panel:

php

$layout = Layout::make('HLCRF')
    ->h('<header>Admin Header</header>')
    ->l('<nav>Sidebar</nav>')
    ->c('<main>Dashboard</main>')
    ->r('<aside>Quick Actions</aside>')
    ->f('<footer>Status Bar</footer>');

The ID System

Every HLCRF element receives a unique, hierarchical ID that describes its position in the layout tree.

ID Format

{Region}-{Index}[-{NestedRegion}-{NestedIndex}]...

Components:

Region Letter - H, L, C, R, or F
Index - Zero-based position within that slot (0, 1, 2, ...)
Nesting - Dash-separated chain for nested layouts

Region Letters

Letter	Region	Semantic Role
`H`	Header	Top navigation, branding
`L`	Left	Primary sidebar, navigation
`C`	Content	Main content area
`R`	Right	Secondary sidebar, widgets
`F`	Footer	Bottom links, copyright

ID Examples

Simple layout:

html

<div data-layout="root">
    <header data-slot="H">
        <div data-block="H-0">First header element</div>
        <div data-block="H-1">Second header element</div>
    </header>
    <main data-slot="C">
        <div data-block="C-0">First content element</div>
    </main>
</div>

Nested layout:

html

<div data-layout="root">
    <main data-slot="C">
        <div data-block="C-0">
            <!-- Nested layout inside content -->
            <div data-layout="C-0-">
                <aside data-slot="C-0-L">
                    <div data-block="C-0-L-0">Nested left sidebar</div>
                </aside>
                <main data-slot="C-0-C">
                    <div data-block="C-0-C-0">Nested content</div>
                </main>
            </div>
        </div>
    </main>
</div>

ID Interpretation

ID	Meaning
`H-0`	First element in Header
`L-2`	Third element in Left sidebar
`C-0`	First element in Content
`C-L-0`	Content > Left > First element
`C-R-2`	Content > Right > Third element
`C-L-0-R-1`	Content > Left > First > Right > Second
`H-0-C-0-L-0`	Header > Content > Left (deeply nested)

Using IDs for CSS

The ID system enables precise CSS targeting:

css

/* Target first header element */
[data-block="H-0"] {
    background: #1a1a2e;
}

/* Target all elements in left sidebar */
[data-slot="L"] > [data-block] {
    padding: 1rem;
}

/* Target nested content areas */
[data-block*="-C-"] {
    margin: 2rem;
}

/* Target second element in any right sidebar */
[data-block$="-R-1"] {
    border-top: 1px solid #e5e7eb;
}

/* Target deeply nested layouts */
[data-layout*="-"][data-layout*="-"] {
    background: #f9fafb;
}

Using IDs for Testing

php

// PHPUnit/Pest
$this->assertSee('[data-block="H-0"]');
$this->assertSeeInOrder(['[data-slot="L"]', '[data-slot="C"]']);

// Playwright/Cypress
await page.locator('[data-block="C-0"]').click();
await expect(page.locator('[data-slot="R"]')).toBeVisible();

Using IDs for JavaScript

javascript

// Target specific elements
const header = document.querySelector('[data-block="H-0"]');
const sidebar = document.querySelector('[data-slot="L"]');

// Dynamic targeting
function getContentBlock(index) {
    return document.querySelector(`[data-block="C-${index}"]`);
}

// Nested targeting
const nestedLeft = document.querySelector('[data-block="C-L-0"]');

Responsive Design Patterns

Mobile-First Stacking

On mobile, stack regions vertically:

blade

<x-hlcrf::layout
    :breakpoints="[
        'mobile' => 'stack',
        'tablet' => 'LC',
        'desktop' => 'LCR',
    ]"
>
    <x-hlcrf::left>Navigation</x-hlcrf::left>
    <x-hlcrf::content>Content</x-hlcrf::content>
    <x-hlcrf::right>Widgets</x-hlcrf::right>
</x-hlcrf::layout>

Behavior:

Mobile (< 768px): Left -> Content -> Right (vertical)
Tablet (768px-1024px): Left | Content (two columns)
Desktop (> 1024px): Left | Content | Right (three columns)

Collapsible Sidebars

blade

<x-hlcrf::left
    collapsible="true"
    collapsed-width="64px"
    expanded-width="256px"
    :collapsed="$sidebarCollapsed"
>
    <div class="sidebar-content">
        @if(!$sidebarCollapsed)
            <span>Full navigation content</span>
        @else
            <span>Icons only</span>
        @endif
    </div>
</x-hlcrf::left>

Hidden Regions on Mobile

blade

<x-hlcrf::right
    class="hidden md:block"
    width="300px"
>
    {{-- Only visible on medium screens and up --}}
    <x-widget-panel />
</x-hlcrf::right>

Flexible Width Distribution

blade

<x-hlcrf::layout>
    <x-hlcrf::left width="250px" class="shrink-0">
        Fixed-width sidebar
    </x-hlcrf::left>

    <x-hlcrf::content class="flex-1 min-w-0">
        Flexible content
    </x-hlcrf::content>

    <x-hlcrf::right width="25%" class="shrink-0">
        Percentage-width sidebar
    </x-hlcrf::right>
</x-hlcrf::layout>

Responsive Grid Inside Content

blade

<x-hlcrf::content>
    <div class="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-4">
        <x-stat-card title="Users" :value="$userCount" />
        <x-stat-card title="Posts" :value="$postCount" />
        <x-stat-card title="Comments" :value="$commentCount" />
    </div>
</x-hlcrf::content>

Complex Real-World Examples

Admin Dashboard

A complete admin dashboard with nested layouts:

php

use Core\Front\Components\Layout;

// Main admin layout
$admin = Layout::make('HLCF')
    ->h(
        '<nav class="flex items-center justify-between px-4 py-2 bg-gray-900 text-white">
            <div class="logo">Admin Panel</div>
            <div class="user-menu">
                <span>user@example.com</span>
            </div>
        </nav>'
    )
    ->l(
        '<nav class="w-64 bg-gray-800 text-gray-300 min-h-screen p-4">
            <a href="/dashboard" class="block py-2">Dashboard</a>
            <a href="/users" class="block py-2">Users</a>
            <a href="/settings" class="block py-2">Settings</a>
        </nav>'
    )
    ->c(
        // Nested layout inside content
        Layout::make('HCR')
            ->h('<div class="flex items-center justify-between p-4 border-b">
                <h1 class="text-xl font-semibold">Dashboard</h1>
                <button class="btn-primary">New Item</button>
            </div>')
            ->c('<div class="p-6">
                <div class="grid grid-cols-3 gap-4 mb-6">
                    <div class="bg-white p-4 rounded shadow">Stat 1</div>
                    <div class="bg-white p-4 rounded shadow">Stat 2</div>
                    <div class="bg-white p-4 rounded shadow">Stat 3</div>
                </div>
                <div class="bg-white p-4 rounded shadow">
                    <h2 class="font-medium mb-4">Recent Activity</h2>
                    <table class="w-full">...</table>
                </div>
            </div>')
            ->r('<aside class="w-80 p-4 bg-gray-50 border-l">
                <h3 class="font-medium mb-4">Quick Actions</h3>
                <div class="space-y-2">
                    <button class="w-full btn-secondary">Export Data</button>
                    <button class="w-full btn-secondary">Generate Report</button>
                </div>
            </aside>')
    )
    ->f(
        '<footer class="px-4 py-2 bg-gray-100 text-gray-600 text-sm">
            Version 1.0.0 | Last sync: 5 minutes ago
        </footer>'
    );

echo $admin->render();

Generated IDs:

H-0 - Admin header/navigation
L-0 - Sidebar navigation
C-0 - Nested layout container
C-0-H-0 - Content header (page title/actions)
C-0-C-0 - Content main area (stats/table)
C-0-R-0 - Content right sidebar (quick actions)
F-0 - Admin footer

E-Commerce Product Page

Product page with nested sections:

php

$productPage = Layout::make('HCF')
    ->h('<header class="border-b">
        <nav>Store Navigation</nav>
        <div>Search | Cart | Account</div>
    </header>')
    ->c(
        Layout::make('LCR')
            ->l('<div class="w-1/2">
                <div class="aspect-square bg-gray-100">
                    <img src="/product-main.jpg" alt="Product" />
                </div>
                <div class="flex gap-2 mt-4">
                    <img src="/thumb-1.jpg" class="w-16 h-16" />
                    <img src="/thumb-2.jpg" class="w-16 h-16" />
                </div>
            </div>')
            ->c(
                // Empty - using left/right only
            )
            ->r('<div class="w-1/2 p-6">
                <h1 class="text-2xl font-bold">Product Name</h1>
                <p class="text-xl text-green-600 mt-2">$99.99</p>
                <p class="mt-4">Product description...</p>

                <div class="mt-6 space-y-4">
                    <select>Size options</select>
                    <button class="w-full btn-primary">Add to Cart</button>
                </div>

                <div class="mt-6 border-t pt-4">
                    <h3>Shipping Info</h3>
                    <p>Free delivery over $50</p>
                </div>
            </div>'),
        // Reviews section
        Layout::make('CR')
            ->c('<div class="p-6">
                <h2 class="text-xl font-bold mb-4">Customer Reviews</h2>
                <div class="space-y-4">
                    <div class="border-b pb-4">Review 1...</div>
                    <div class="border-b pb-4">Review 2...</div>
                </div>
            </div>')
            ->r('<aside class="w-64 p-4 bg-gray-50">
                <h3>You May Also Like</h3>
                <div class="space-y-2">
                    <div>Related Product 1</div>
                    <div>Related Product 2</div>
                </div>
            </aside>')
    )
    ->f('<footer class="bg-gray-900 text-white p-8">
        <div class="grid grid-cols-4 gap-8">
            <div>About Us</div>
            <div>Customer Service</div>
            <div>Policies</div>
            <div>Newsletter</div>
        </div>
    </footer>');

Multi-Panel Settings Page

Settings page with multiple nested panels:

php

$settings = Layout::make('HLC')
    ->h('<header class="border-b p-4">
        <h1>Account Settings</h1>
    </header>')
    ->l('<nav class="w-48 border-r">
        <a href="#profile" class="block p-3 bg-blue-50">Profile</a>
        <a href="#security" class="block p-3">Security</a>
        <a href="#notifications" class="block p-3">Notifications</a>
        <a href="#billing" class="block p-3">Billing</a>
    </nav>')
    ->c(
        // Profile section
        Layout::make('HCF')
            ->h('<div class="p-4 border-b">
                <h2 class="font-semibold">Profile Information</h2>
                <p class="text-gray-600 text-sm">Update your account details</p>
            </div>')
            ->c('<form class="p-6 space-y-4">
                <div>
                    <label>Name</label>
                    <input type="text" value="John Doe" />
                </div>
                <div>
                    <label>Email</label>
                    <input type="email" value="john@example.com" />
                </div>
                <div>
                    <label>Bio</label>
                    <textarea rows="4"></textarea>
                </div>
            </form>')
            ->f('<div class="p-4 border-t bg-gray-50 flex justify-end gap-2">
                <button class="btn-secondary">Cancel</button>
                <button class="btn-primary">Save Changes</button>
            </div>')
    );

Documentation Site

Documentation layout with table of contents:

php

$docs = Layout::make('HLCRF')
    ->h('<header class="border-b">
        <div class="flex items-center justify-between px-6 py-3">
            <div class="flex items-center gap-4">
                <img src="/logo.svg" class="h-8" />
                <nav class="hidden md:flex gap-6">
                    <a href="/docs">Docs</a>
                    <a href="/api">API</a>
                    <a href="/examples">Examples</a>
                </nav>
            </div>
            <div class="flex items-center gap-4">
                <input type="search" placeholder="Search..." />
                <a href="/github">GitHub</a>
            </div>
        </div>
    </header>')
    ->l('<nav class="w-64 p-4 border-r overflow-y-auto">
        <h4 class="font-semibold text-gray-500 uppercase text-xs mb-2">Getting Started</h4>
        <a href="/docs/intro" class="block py-1 text-blue-600">Introduction</a>
        <a href="/docs/install" class="block py-1">Installation</a>
        <a href="/docs/quick-start" class="block py-1">Quick Start</a>

        <h4 class="font-semibold text-gray-500 uppercase text-xs mt-6 mb-2">Core Concepts</h4>
        <a href="/docs/layouts" class="block py-1">Layouts</a>
        <a href="/docs/components" class="block py-1">Components</a>
        <a href="/docs/routing" class="block py-1">Routing</a>
    </nav>')
    ->c('<article class="prose max-w-3xl mx-auto p-8">
        <h1>Introduction</h1>
        <p>Welcome to the documentation...</p>

        <h2>Key Features</h2>
        <ul>
            <li>Feature 1</li>
            <li>Feature 2</li>
            <li>Feature 3</li>
        </ul>

        <h2>Next Steps</h2>
        <p>Continue to the installation guide...</p>
    </article>')
    ->r('<aside class="w-48 p-4 border-l">
        <h4 class="font-semibold text-sm mb-2">On This Page</h4>
        <nav class="text-sm space-y-1">
            <a href="#intro" class="block text-gray-600">Introduction</a>
            <a href="#features" class="block text-gray-600">Key Features</a>
            <a href="#next" class="block text-gray-600">Next Steps</a>
        </nav>
    </aside>')
    ->f('<footer class="border-t p-4 flex justify-between text-sm text-gray-600">
        <div>
            <a href="/prev" class="text-blue-600">&larr; Previous: Setup</a>
        </div>
        <div>
            <a href="/next" class="text-blue-600">Next: Installation &rarr;</a>
        </div>
    </footer>');

Email Client Interface

Complex email client with multiple nested panels:

php

$email = Layout::make('HLCR')
    ->h('<header class="bg-white border-b px-4 py-2 flex items-center justify-between">
        <div class="flex items-center gap-4">
            <button class="btn-icon">Menu</button>
            <img src="/logo.svg" class="h-6" />
        </div>
        <div class="flex-1 max-w-2xl mx-4">
            <input type="search" placeholder="Search mail" class="w-full" />
        </div>
        <div class="flex items-center gap-2">
            <button class="btn-icon">Settings</button>
            <div class="avatar">JD</div>
        </div>
    </header>')
    ->l('<aside class="w-64 border-r flex flex-col">
        <div class="p-3">
            <button class="w-full btn-primary">Compose</button>
        </div>
        <nav class="flex-1 overflow-y-auto">
            <a href="#inbox" class="flex items-center gap-3 px-4 py-2 bg-blue-50">
                <span class="icon">inbox</span>
                <span class="flex-1">Inbox</span>
                <span class="badge">12</span>
            </a>
            <a href="#starred" class="flex items-center gap-3 px-4 py-2">
                <span class="icon">star</span>
                <span>Starred</span>
            </a>
            <a href="#sent" class="flex items-center gap-3 px-4 py-2">
                <span class="icon">send</span>
                <span>Sent</span>
            </a>
            <a href="#drafts" class="flex items-center gap-3 px-4 py-2">
                <span class="icon">draft</span>
                <span>Drafts</span>
            </a>
        </nav>
        <div class="p-4 border-t text-sm text-gray-600">
            Storage: 2.4 GB / 15 GB
        </div>
    </aside>')
    ->c(
        Layout::make('LC')
            ->l('<div class="w-80 border-r overflow-y-auto">
                <div class="p-2 border-b">
                    <select class="w-full text-sm">
                        <option>All Mail</option>
                        <option>Unread</option>
                        <option>Starred</option>
                    </select>
                </div>
                <div class="divide-y">
                    <div class="p-3 bg-blue-50 cursor-pointer">
                        <div class="flex items-center justify-between">
                            <span class="font-medium">John Smith</span>
                            <span class="text-xs text-gray-500">10:30 AM</span>
                        </div>
                        <div class="font-medium text-sm">Meeting Tomorrow</div>
                        <div class="text-sm text-gray-600 truncate">Hi, just wanted to confirm...</div>
                    </div>
                    <div class="p-3 cursor-pointer">
                        <div class="flex items-center justify-between">
                            <span class="font-medium">Jane Doe</span>
                            <span class="text-xs text-gray-500">Yesterday</span>
                        </div>
                        <div class="font-medium text-sm">Project Update</div>
                        <div class="text-sm text-gray-600 truncate">Here is the latest update...</div>
                    </div>
                </div>
            </div>')
            ->c('<div class="flex-1 flex flex-col">
                <div class="p-4 border-b flex items-center gap-2">
                    <button class="btn-icon">Archive</button>
                    <button class="btn-icon">Delete</button>
                    <button class="btn-icon">Move</button>
                    <span class="border-l h-6 mx-2"></span>
                    <button class="btn-icon">Reply</button>
                    <button class="btn-icon">Forward</button>
                </div>
                <div class="flex-1 overflow-y-auto p-6">
                    <div class="mb-6">
                        <h2 class="text-xl font-medium">Meeting Tomorrow</h2>
                        <div class="flex items-center gap-3 mt-2 text-sm text-gray-600">
                            <div class="avatar">JS</div>
                            <div>
                                <div>John Smith &lt;john@example.com&gt;</div>
                                <div>to me</div>
                            </div>
                            <div class="ml-auto">Jan 15, 2026, 10:30 AM</div>
                        </div>
                    </div>
                    <div class="prose">
                        <p>Hi,</p>
                        <p>Just wanted to confirm our meeting tomorrow at 2pm.</p>
                        <p>Best regards,<br>John</p>
                    </div>
                </div>
            </div>')
    )
    ->r('<aside class="w-64 border-l p-4 hidden xl:block">
        <h3 class="font-medium mb-4">Contact Info</h3>
        <div class="text-sm space-y-2">
            <div>John Smith</div>
            <div class="text-gray-600">john@example.com</div>
            <div class="text-gray-600">+1 555 123 4567</div>
        </div>
        <h3 class="font-medium mt-6 mb-4">Related Emails</h3>
        <div class="text-sm space-y-2">
            <a href="#" class="block text-blue-600">Re: Project Timeline</a>
            <a href="#" class="block text-blue-600">Meeting Notes</a>
        </div>
    </aside>');

Performance Considerations

Lazy Content Loading

For large layouts, defer non-critical content:

php

$layout = Layout::make('LCR')
    ->l('<nav>Immediate navigation</nav>')
    ->c('<main wire:init="loadContent">
        <div wire:loading>Loading...</div>
        <div wire:loading.remove>@livewire("content-panel")</div>
    </main>')
    ->r(fn () => view('widgets.sidebar')); // Closure defers evaluation

Conditional Region Rendering

Only render regions when needed:

php

$layout = Layout::make('LCR');

$layout->l('<nav>Navigation</nav>');
$layout->c('<main>Content</main>');

// Conditionally add right sidebar
if ($user->hasFeature('widgets')) {
    $layout->r('<aside>Widgets</aside>');
}

Efficient CSS Targeting

Use data attributes instead of deep selectors:

css

/* Efficient - uses data attribute */
[data-block="C-0"] { padding: 1rem; }

/* Less efficient - deep selector */
.hlcrf-layout > .hlcrf-body > .hlcrf-content > div:first-child { padding: 1rem; }

Testing HLCRF Layouts

Unit Testing

php

use Core\Front\Components\Layout;
use PHPUnit\Framework\TestCase;

class LayoutTest extends TestCase
{
    public function test_generates_correct_ids(): void
    {
        $layout = Layout::make('LC')
            ->l('Left')
            ->c('Content');

        $html = $layout->render();

        $this->assertStringContainsString('data-slot="L"', $html);
        $this->assertStringContainsString('data-slot="C"', $html);
        $this->assertStringContainsString('data-block="L-0"', $html);
        $this->assertStringContainsString('data-block="C-0"', $html);
    }

    public function test_nested_layout_ids(): void
    {
        $nested = Layout::make('LR')
            ->l('Nested Left')
            ->r('Nested Right');

        $outer = Layout::make('C')
            ->c($nested);

        $html = $outer->render();

        $this->assertStringContainsString('data-block="C-0-L-0"', $html);
        $this->assertStringContainsString('data-block="C-0-R-0"', $html);
    }
}

Browser Testing

php

// Pest with Playwright
it('renders admin layout correctly', function () {
    $this->browse(function ($browser) {
        $browser->visit('/admin')
            ->assertPresent('[data-layout="root"]')
            ->assertPresent('[data-slot="H"]')
            ->assertPresent('[data-slot="L"]')
            ->assertPresent('[data-slot="C"]');
    });
});

Best Practices

1. Use Semantic Region Names

php

// Good - semantic use
->h('<nav>Global navigation</nav>')
->l('<nav>Page navigation</nav>')
->c('<main>Page content</main>')
->r('<aside>Related content</aside>')
->f('<footer>Site footer</footer>')

// Bad - misuse of regions
->h('<aside>Sidebar content</aside>')  // Header for sidebar?

2. Leverage the ID System

css

/* Target specific elements precisely */
[data-block="H-0"] { /* Header first element */ }
[data-block="C-L-0"] { /* Content > Left > First */ }

/* Don't fight the system with complex selectors */

3. Keep Nesting Shallow

php

// Good - 2-3 levels max
Layout::make('HCF')
    ->c(Layout::make('LCR')->...);

// Avoid - too deep
Layout::make('C')
    ->c(Layout::make('C')
        ->c(Layout::make('C')
            ->c(Layout::make('C')...))));

4. Use Consistent Widths

php

// Good - consistent sidebar widths across app
->l('<nav class="w-64">')  // Always 256px
->r('<aside class="w-80">') // Always 320px

5. Handle Empty Regions Gracefully

php

// Regions without content don't render
$layout = Layout::make('LCR')
    ->l('<nav>Nav</nav>')
    ->c('<main>Content</main>');
    // No ->r() call - right sidebar won't render

HLCRF Deep Dive ​

Layout Combinations ​

All Possible Combinations ​

Content-Only (C) ​

Header + Content + Footer (HCF) ​

Left + Content (LC) ​

Three-Column (LCR) ​

Full Admin (HLCRF) ​

The ID System ​

ID Format ​

Region Letters ​

ID Examples ​

ID Interpretation ​

Using IDs for CSS ​

Using IDs for Testing ​

Using IDs for JavaScript ​

Responsive Design Patterns ​

Mobile-First Stacking ​

Collapsible Sidebars ​

Hidden Regions on Mobile ​

Flexible Width Distribution ​

Responsive Grid Inside Content ​

Complex Real-World Examples ​

Admin Dashboard ​

E-Commerce Product Page ​

Multi-Panel Settings Page ​

Documentation Site ​

Email Client Interface ​

Performance Considerations ​

Lazy Content Loading ​

Conditional Region Rendering ​

Efficient CSS Targeting ​

Testing HLCRF Layouts ​

Unit Testing ​

Browser Testing ​

Best Practices ​

1. Use Semantic Region Names ​

2. Leverage the ID System ​

3. Keep Nesting Shallow ​

4. Use Consistent Widths ​

5. Handle Empty Regions Gracefully ​

Learn More ​

HLCRF Deep Dive

Layout Combinations

All Possible Combinations

Content-Only (C)

Header + Content + Footer (HCF)

Left + Content (LC)

Three-Column (LCR)

Full Admin (HLCRF)

The ID System

ID Format

Region Letters

ID Examples

ID Interpretation

Using IDs for CSS

Using IDs for Testing

Using IDs for JavaScript

Responsive Design Patterns

Mobile-First Stacking

Collapsible Sidebars

Hidden Regions on Mobile

Flexible Width Distribution

Responsive Grid Inside Content

Complex Real-World Examples

Admin Dashboard

E-Commerce Product Page

Multi-Panel Settings Page

Documentation Site

Email Client Interface

Performance Considerations

Lazy Content Loading

Conditional Region Rendering

Efficient CSS Targeting

Testing HLCRF Layouts

Unit Testing

Browser Testing

Best Practices

1. Use Semantic Region Names

2. Leverage the ID System

3. Keep Nesting Shallow

4. Use Consistent Widths

5. Handle Empty Regions Gracefully

Learn More