body {
  font-family: 'Poppins', sans-serif;
  background: #f5faf7;
  color: #333;
  margin: 0;
  padding: 0;
}

.plan-banner {
  background-color: #c2f5d5;
  text-align: center;
  padding: 10px;
  font-weight: 500;
  color: #2d5932;
}

.shell {
  max-width: 800px;
  margin: 40px auto;
  padding: 20px;
  background: #fff;
  border-radius: 16px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.hero {
  text-align: center;
  margin-bottom: 20px;
}

.title {
  font-size: 2em;
  color: #25976b;
}

.subtitle {
  font-size: 1.1em;
  color: #555;
}

.chat {
  border: 1px solid #e0e0e0;
  border-radius: 12px;
  padding: 16px;
  background: #fafafa;
}

.chat-log {
  max-height: 350px;
  overflow-y: auto;
  padding: 10px;
  margin-bottom: 10px;
}

.message {
  padding: 10px 14px;
  border-radius: 14px;
  margin-bottom: 10px;
  max-width: 80%;
}

.message.user {
  background-color: #d2f8d2;
  align-self: flex-end;
  text-align: right;
  margin-left: auto;
}

.message.ai {
  background-color: #e7f0ff;
  text-align: left;
  color: #333;
}

.message.typing {
  font-style: italic;
  opacity: 0.7;
}

.chat-input {
  display: flex;
  gap: 10px;
}

.chat-input input {
  flex: 1;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 8px;
  font-size: 1em;
}

.btn {
  padding: 10px 16px;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 600;
  transition: background 0.3s;
}

.btn.primary {
  background-color: #25c283;
  color: white;
}

.btn.primary:hover {
  background-color: #1da971;
}

.btn.ghost {
  background-color: transparent;
  color: #25c283;
  border: 2px solid #25c283;
}

.btn.ghost:hover {
  background-color: #e5f8ef;
}

.limit-note {
  text-align: center;
  color: #b33a3a;
  margin-top: 10px;
  font-weight: bold;
}

.about {
  margin-top: 30px;
  padding-top: 10px;
  border-top: 1px solid #eee;
}

.footer {
  text-align: center;
  padding: 20px;
  color: #777;
  font-size: 0.9em;
}