Building a Chatbot from Scratch: Part 5 - Styling

Our chatbot works. Now let's make it look professional with modern CSS.

Series Recap

• [Part 1](/blog/building-chatbot-from-scratch-part-1-setup): Project setup
• [Part 2](/blog/building-chatbot-from-scratch-part-2-ui): Chat UI
• [Part 3](/blog/building-chatbot-part-3-websockets): WebSockets
• [Part 4](/blog/building-chatbot-part-4-adding-intelligence): Response logic

Time to make it pretty.

The Design

We're going for:

• Clean, modern chat interface
• User messages on the right
• Bot messages on the left
• Typing indicator
• Smooth animations

Base Styles

:root {
  --bg-primary: #1a1a2e;
  --bg-secondary: #16213e;
  --accent: #0f3460;
  --text: #e4e4e7;
  --user-bubble: #3b82f6;
  --bot-bubble: #374151;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg-primary);
  color: var(--text);
}

Chat Container

.chat-container {
  max-width: 500px;
  height: 100vh;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  background: var(--bg-secondary);
}

.chat-header {
  padding: 1rem;
  background: var(--accent);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.chat-header .avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--user-bubble);
  display: flex;
  align-items: center;
  justify-content: center;
}

.chat-header .status {
  font-size: 0.875rem;
  opacity: 0.7;
}

Messages Area

.messages {
  flex: 1;
  overflow-y: auto;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.message {
  max-width: 80%;
  padding: 0.75rem 1rem;
  border-radius: 1rem;
  animation: fadeIn 0.2s ease;
}

.message.user {
  align-self: flex-end;
  background: var(--user-bubble);
  border-bottom-right-radius: 0.25rem;
}

.message.bot {
  align-self: flex-start;
  background: var(--bot-bubble);
  border-bottom-left-radius: 0.25rem;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

Input Area

.input-area {
  padding: 1rem;
  background: var(--accent);
  display: flex;
  gap: 0.5rem;
}

.input-area input {
  flex: 1;
  padding: 0.75rem 1rem;
  border: none;
  border-radius: 1.5rem;
  background: var(--bg-secondary);
  color: var(--text);
  font-size: 1rem;
}

.input-area input:focus {
  outline: 2px solid var(--user-bubble);
}

.input-area button {
  padding: 0.75rem 1.25rem;
  border: none;
  border-radius: 1.5rem;
  background: var(--user-bubble);
  color: white;
  cursor: pointer;
  transition: opacity 0.2s;
}

.input-area button:hover {
  opacity: 0.9;
}

Typing Indicator

.typing-indicator {
  display: flex;
  gap: 4px;
  padding: 0.75rem 1rem;
  background: var(--bot-bubble);
  border-radius: 1rem;
  width: fit-content;
}

.typing-indicator span {
  width: 8px;
  height: 8px;
  background: var(--text);
  border-radius: 50%;
  animation: bounce 1.4s infinite ease-in-out;
}

.typing-indicator span:nth-child(1) { animation-delay: 0s; }
.typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
.typing-indicator span:nth-child(3) { animation-delay: 0.4s; }

@keyframes bounce {
  0%, 80%, 100% { transform: translateY(0); }
  40% { transform: translateY(-6px); }
}

The Result

A professional-looking chat interface with:

• Dark mode aesthetic
• Smooth animations
• Clear visual hierarchy
• Responsive design

What's Next

In the final part, we'll deploy our chatbot and make it accessible to the world.

Full code: github.com/chrishacia/simple-chatbot

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