high-contrast – skill Thiết kế & UI cho agent AI

High Contrast Design

> "Stark visual contrast. Accessibility still requires semantic, interaction and user testing."

When to Use

Use this sub-style when the user's request matches the aesthetic described above. This is a child reference of the design-it skill and is not meant to be triggered directly.

Core Principles

1. Measure Relevant Contrast: WCAG AAA text contrast is at least 7:1 for normal text and 4.5:1 for large text. Non-text controls have distinct criteria; high contrast alone does not establish AAA conformance.

2. Clear Boundaries: Interactive elements have highly visible borders and focus states.

3. No Ambiguity: Avoid subtle greys, low-opacity text, or purely decorative elements that distract from the core content.

Visual DNA

• Colors: Industrial Chic (Black and White) or Modern Editorial. Often uses a single, highly luminous accent color (like pure Yellow #FFFF00 or Cyan #00FFFF) against black.
• Typography: Highly legible, robust sans-serifs (Atkinson Hyperlegible, Inter, Roboto). Large base font sizes (18px+).
• Styling: Solid 2px borders around cards and buttons. Avoid drop shadows as they reduce edge clarity.

Web Implementation

• Focus heavily on focus states (:focus-visible) and clear active states.
• CSS Example:

:root {
  --hc-bg: #ffffff;
  --hc-text: #000000;
  --hc-accent: #0000FF; /* Pure blue */
  --hc-focus: #FF00FF; /* High visibility focus ring */
}

body {
  background-color: var(--hc-bg);
  color: var(--hc-text);
  font-family: 'Atkinson Hyperlegible', sans-serif;
  font-size: 18px; /* Larger default */
}

.hc-card {
  background-color: #ffffff;
  border: 3px solid #000000; /* Unmissable boundary */
  padding: 32px;
  border-radius: 8px;
}

.hc-btn {
  background-color: var(--hc-accent);
  color: #ffffff;
  border: 3px solid transparent; /* Reserve space for focus */
  border-radius: 4px;
  padding: 16px 32px;
  font-weight: 700;
  font-size: 1.1rem;
  cursor: pointer;
}

/* Crucial for high contrast / accessibility */
.hc-btn:focus-visible, a:focus-visible {
  outline: 4px solid var(--hc-focus);
  outline-offset: 4px;
}

a {
  color: var(--hc-accent);
  text-decoration: underline;
  text-decoration-thickness: 2px;
}

App Implementation

SwiftUI

struct HighContrastView: View {
    var body: some View {
        VStack(spacing: 32) {
            // High Contrast Card
            VStack(alignment: .leading, spacing: 16) {
                Text("Maximum Legibility")
                    .font(.custom("Atkinson Hyperlegible", size: 24))
                    .fontWeight(.bold)
                    .foregroundColor(.black)
                
                Text("Content is king. Borders are stark. Contrast ratios exceed 7:1.")
                    .font(.custom("Atkinson Hyperlegible", size: 18))
                    .foregroundColor(.black)
            }
            .padding(32)
            .background(Color.white)
            .overlay(
                RoundedRectangle(cornerRadius: 8)
                    .stroke(Color.black, lineWidth: 3)
            )
            
            // High Contrast Action Button
            Button(action: {}) {
                Text("CONFIRM ACTION")
                    .font(.custom("Atkinson Hyperlegible", size: 18))
                    .fontWeight(.black)
                    .foregroundColor(.white)
                    .padding(.vertical, 16)
                    .padding(.horizontal, 32)
                    .background(Color(red: 0, green: 0, blue: 1)) // Explicit #0000FF, not adaptive system blue
                    .cornerRadius(4)
            }
        }
        .padding()
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .background(Color.white)
    }
}

• Rely on thick .stroke(Color.black, lineWidth: 3) overlays.
• Ensure text is pure .black on pure .white. Do not use .secondary colors if they drop below a 7:1 contrast ratio.
• Use fonts specifically designed for legibility, like Atkinson Hyperlegible.

Flutter

class HighContrastScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white,
      body: Center(
        child: Padding(
          padding: const EdgeInsets.all(24.0),
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              // High Contrast Card
              Container(
                width: double.infinity,
                padding: const EdgeInsets.all(32),
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.circular(8),
                  border: Border.all(color: Colors.black, width: 3), // Unmissable boundary
                ),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: const [
                    Text('Maximum Legibility', 
                      style: TextStyle(fontFamily: 'Atkinson', fontSize: 24, fontWeight: FontWeight.bold, color: Colors.black)),
                    SizedBox(height: 16),
                    Text('Content is king. Borders are stark. Contrast ratios exceed 7:1.', 
                      style: TextStyle(fontFamily: 'Atkinson', fontSize: 18, color: Colors.black)),
                  ],
                ),
              ),
              const SizedBox(height: 32),
              
              // High Contrast Button
              ElevatedButton(
                onPressed: () {},
                style: ElevatedButton.styleFrom(
                  backgroundColor: const Color(0xFF0000FF), // Pure blue
                  foregroundColor: Colors.white,
                  padding: const EdgeInsets.symmetric(horizontal: 32, vertical: 16),
                  shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(4)),
                  elevation: 0, // No shadows
                ),
                child: const Text('CONFIRM ACTION', 
                  style: TextStyle(fontFamily: 'Atkinson', fontSize: 18, fontWeight: FontWeight.w900)),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

• Disable elevation on buttons; shadows blur the edges and reduce contrast.
• Use Border.all(color: Colors.black, width: 3) on containers to explicitly define spatial boundaries for users with low vision.

React Native

const HighContrastScreen = () => {
  return (
    <View style={{ flex: 1, backgroundColor: '#FFFFFF', padding: 24, justifyContent: 'center' }}>
      
      {/* High Contrast Card */}
      <View style={{
        backgroundColor: '#FFFFFF',
        borderColor: '#000000',
        borderWidth: 3,
        borderRadius: 8,
        padding: 32,
        marginBottom: 32
      }}>
        <Text style={{ fontFamily: 'Atkinson-Bold', fontSize: 24, color: '#000000', marginBottom: 16 }}>
          Maximum Legibility
        </Text>
        <Text style={{ fontFamily: 'Atkinson-Regular', fontSize: 18, color: '#000000' }}>
          Content is king. Borders are stark. Contrast ratios exceed 7:1.
        </Text>
      </View>

      {/* High Contrast Button */}
      <TouchableOpacity style={{
        backgroundColor: '#0000FF',
        paddingVertical: 16,
        paddingHorizontal: 32,
        borderRadius: 4,
        alignItems: 'center'
      }}>
        <Text style={{ fontFamily: 'Atkinson-Bold', fontSize: 18, color: '#FFFFFF', fontWeight: '900' }}>
          CONFIRM ACTION
        </Text>
      </TouchableOpacity>
      
    </View>
  );
};

• In React Native, accessibility relies heavily on high contrast. Ensure borderWidth: 3 and explicit pure #000000 text colors.
• Make sure to use accessible <TouchableOpacity> areas (a target area of at least 48×48 logical units where required by the platform; target size is not padding).

Jetpack Compose

@Composable
fun HighContrastScreen() {
    Column(
        modifier = Modifier
            .fillMaxSize()
            .background(Color.White)
            .padding(24.dp),
        verticalArrangement = Arrangement.Center
    ) {
        // High Contrast Card
        Box(
            modifier = Modifier
                .fillMaxWidth()
                .background(Color.White, RoundedCornerShape(8.dp))
                .border(3.dp, Color.Black, RoundedCornerShape(8.dp))
                .padding(32.dp)
        ) {
            Column {
                Text(
                    text = "Maximum Legibility",
                    fontSize = 24.sp,
                    fontWeight = FontWeight.Bold,
                    color = Color.Black
                )
                Spacer(Modifier.height(16.dp))
                Text(
                    text = "Content is king. Borders are stark. Contrast ratios exceed 7:1.",
                    fontSize = 18.sp,
                    color = Color.Black
                )
            }
        }
     

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