Frontend Design

Create distinctive frontend interfaces that avoid generic "AI slop" aesthetics. Implement real working code with exceptional attention to aesthetic details.

Quick Reference

CSS Variables Reference: See references/css-variables.md for complete list of all CSS variables (--bs-*, --fin-*, --agent-*).

Premium Effects Reference: See references/premium-effects.md for aurora background, scroll reveal, and other premium visual effects.

Decision Tree

Does the screen belong to an EXISTING module?
│
├─ YES → Use existing CSS/JS files
│        Use existing class prefix (fin-*, cart-*, exp-*, etc.)
│        EXTEND, don't recreate
│
└─ NO  → Create NEW design system
         Choose unique class prefix
         Follow creation guidelines below

Known Design Systems

Using Existing Systems

Template Structure (with Premium Effects)

{% extends "base.html" %}

{% block title %}Page Title{% endblock %}

{% block extra_css %}
<link rel="stylesheet" href="{{ url_for('static', filename='css/[module]/[module].css') }}">
{% endblock %}

{% block content %}
<div class="container-fluid premium-page">
    <header class="page-header reveal">
        <div class="d-flex justify-content-between align-items-center mb-4">
            <div>
                <h1 class="h3 mb-0">
                    <i class="fas fa-icon text-primary me-2"></i>
                    Título
                </h1>
                <small class="text-muted">Subtítulo</small>
            </div>
        </div>
    </header>
    <!-- Content -->
</div>
{% endblock %}

Key classes:

• premium-page → Auto-injects aurora background (centralized in base.html)
• reveal → Scroll reveal animation for headers/sections

For complete premium effects guide: references/premium-effects.md

Essential Patterns

Card:

.my-card {
    background: var(--bs-secondary-bg);
    border: 1px solid var(--bs-border-color);
    border-radius: 12px;
}

Table:

.table-container thead th {
    background: var(--bs-tertiary-bg);
    color: var(--bs-secondary-color);
}

For complete patterns: See css-variables.md#6

Creating New Systems

Step 1: Define Identity

Step 2: CSS Variables Template

/* === [MODULE] DESIGN SYSTEM === */
:root {
    /* Backgrounds */
    --[prefix]-bg-primary: #0a1628;
    --[prefix]-bg-secondary: #111d2e;
    --[prefix]-bg-tertiary: #1a2942;

    /* Texto */
    --[prefix]-text-primary: #f0f6fc;
    --[prefix]-text-secondary: #8b949e;

    /* Acentos */
    --[prefix]-accent-primary: #00d4aa;
    --[prefix]-accent-success: #10b981;
    --[prefix]-accent-warning: #f59e0b;
    --[prefix]-accent-danger: #ef4444;
}

[data-theme="light"] {
    --[prefix]-bg-primary: #ffffff;
    /* ... light mode overrides */
}

Step 3: Signature Visual Moments (pick 2+)

A. Atmospheric Background:

.[prefix]-container::before {
    content: '';
    position: fixed;
    background: radial-gradient(
        ellipse at 70% 30%,
        rgba(var(--bs-primary-rgb), 0.08) 0%,
        transparent 60%
    );
    pointer-events: none;
}

B. Entry Animation:

@keyframes [prefix]-fadeIn {
    from { opacity: 0; transform: translateY(20px); filter: blur(4px); }
    to { opacity: 1; transform: translateY(0); filter: blur(0); }
}

C. Progressive Glow Line:

.[prefix]-card::after {
    content: '';
    position: absolute;
    bottom: 0; left: 0;
    width: 0; height: 3px;
    background: linear-gradient(90deg, var(--bs-primary), var(--bs-info));
    transition: width 0.4s ease;
}
.[prefix]-card:hover::after { width: 100%; }

Quality Checklist

• Uses CSS variables (NOT hex colors)
• Dark mode complete
• Light mode complete (NOT just inverted)
• Theme toggle functional
• premium-page class on main container
• reveal class on header/sections
• At least 2 signature visual moments
• Reduced motion respected (@media (prefers-reduced-motion))
• WCAG AA contrast (4.5:1)

FORBIDDEN

/* ❌ NEVER USE */
background: #343541;     /* Fixed hex */
background: #0d1117;     /* GitHub Dark */
--accent: #58a6ff;       /* GitHub Blue */
font-family: Arial;      /* Generic font */

Always use: var(--bs-*), var(--fin-*), or var(--agent-*) depending on module.

If you need to check the availables variables: See references/css-variables.md