:root {
  --primary-color: #4e7aff;
  --primary-light: #e1e8ff;
  --secondary-color: #f8f9fc;
  --bot-message-bg: #f0f7ff;
  --user-message-bg: #e9f7ef;
  --text-color: #333844;
  --border-radius: 16px;
  --box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
  --accent-color: #6c5ce7;
  --border-color: #e6e8f0;
  --recording-color: #ff5252;
  --voice-on-color: #2ecc71;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background-color: var(--secondary-color);
  font-size: 18px;
  padding: 20px;
  background-image: linear-gradient(135deg, #f5f7ff 0%, #eef1f5 100%);
  min-height: 100vh;
}

.chat-container {
  max-width: 1100px;
  margin: 0 auto;
  background-color: white;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  padding: 25px;
  display: flex;
  flex-direction: column;
  height: 90vh;
  border: 1px solid var(--border-color);
  position: relative;
  overflow: hidden;
}

h1 {
  color: var(--primary-color);
  text-align: center;
  margin-bottom: 15px;
  font-size: 2.2rem;
  font-weight: 600;
}

.controls {
  display: flex;
  justify-content: flex-end;
  margin-bottom: 10px;
}

.control-btn {
  background-color: var(--primary-light);
  border: 1px solid var(--border-color);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s ease;
  color: var(--primary-color);
}

.control-btn:hover {
  background-color: var(--primary-color);
  color: white;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(78, 122, 255, 0.15);
}

.control-btn.active {
  background-color: var(--voice-on-color);
  color: white;
}

.chat-area {
  display: flex;
  flex: 1;
  overflow: hidden;
  margin-bottom: 20px;
  gap: 20px;
}

.topic-suggestions {
  width: 280px;
  background-color: var(--primary-light);
  border-radius: var(--border-radius);
  padding: 15px;
  overflow-y: auto;
  flex-shrink: 0;
  border: 1px solid var(--border-color);
}

.topic-category {
  margin-bottom: 15px;
}

.topic-category h3 {
  font-size: 1.1rem;
  margin-bottom: 10px;
  color: var(--accent-color);
  padding-bottom: 5px;
  border-bottom: 1px solid rgba(108, 92, 231, 0.2);
}

.topic-btn {
  display: block;
  background-color: white;
  border: 1px solid var(--border-color);
  padding: 10px 15px;
  margin-bottom: 8px;
  border-radius: 8px;
  width: 100%;
  text-align: left;
  font-size: 0.95rem;
  cursor: pointer;
  transition: all 0.2s ease;
  color: var(--text-color);
}

.topic-btn:hover {
  background-color: var(--primary-color);
  color: white;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(78, 122, 255, 0.15);
}

.chat-log {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  background-color: white;
  scrollbar-width: thin;
}

.chat-log::-webkit-scrollbar {
  width: 6px;
}

.chat-log::-webkit-scrollbar-thumb {
  background-color: rgba(78, 122, 255, 0.3);
  border-radius: 10px;
}

.message {
  margin-bottom: 24px;
  padding: 16px 20px;
  border-radius: var(--border-radius);
  max-width: 85%;
  font-size: 1.2rem;
  line-height: 1.5;
  position: relative;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.04);
}

.user-message {
  background-color: var(--user-message-bg);
  margin-left: auto;
  border-bottom-right-radius: 4px;
  border: 1px solid rgba(46, 204, 113, 0.1);
}

.bot-message {
  background-color: var(--bot-message-bg);
  border-bottom-left-radius: 4px;
  border: 1px solid rgba(78, 122, 255, 0.1);
}

.message::before {
  content: '';
  position: absolute;
  bottom: -8px;
  width: 15px;
  height: 15px;
}

.user-message::before {
  right: 15px;
  background: radial-gradient(circle at top right, transparent 15px, var(--user-message-bg) 0);
}

.bot-message::before {
  left: 15px;
  background: radial-gradient(circle at top left, transparent 15px, var(--bot-message-bg) 0);
}

#chat-form {
  display: flex;
  gap: 10px;
  margin-top: 10px;
}

#user-input {
  flex: 1;
  padding: 16px;
  font-size: 1.1rem;
  border: 2px solid var(--border-color);
  border-radius: var(--border-radius);
  outline: none;
  transition: all 0.3s;
  background-color: white;
}

#user-input:focus {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 4px rgba(78, 122, 255, 0.1);
}

.voice-btn {
  padding: 0 15px;
  background-color: var(--primary-color);
  color: white;
  border: none;
  border-radius: var(--border-radius);
  cursor: pointer;
  font-size: 1.1rem;
  transition: all 0.3s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.voice-btn:hover {
  background-color: #3a66f0;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(78, 122, 255, 0.25);
}

.voice-btn.recording {
  background-color: var(--recording-color);
  animation: pulse 1.5s infinite;
}

#send-btn {
  padding: 12px 25px;
  background-color: var(--primary-color);
  color: white;
  border: none;
  border-radius: var(--border-radius);
  cursor: pointer;
  font-size: 1.1rem;
  font-weight: bold;
  transition: all 0.3s;
}

#send-btn:hover {
  background-color: #3a66f0;
  transform: translateY(-2px);
  box-shadow: 0 4px 8px rgba(78, 122, 255, 0.25);
}

#send-btn:active {
  transform: translateY(0);
}

.loading {
  display: flex;
  padding: 15px;
  align-items: center;
}

.loading-dot {
  width: 10px;
  height: 10px;
  margin: 0 4px;
  background-color: var(--primary-color);
  border-radius: 50%;
  animation: bounce 1.5s infinite ease-in-out;
  opacity: 0.7;
}

.loading-dot:nth-child(2) {
  animation-delay: 0.2s;
}

.loading-dot:nth-child(3) {
  animation-delay: 0.4s;
}

.voice-indicator {
  position: absolute;
  bottom: 90px;
  left: 50%;
  transform: translateX(-50%);
  background-color: rgba(0, 0, 0, 0.7);
  color: white;
  padding: 15px 30px;
  border-radius: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 15px;
  transition: all 0.3s ease;
  z-index: 10;
}

.voice-indicator.hidden {
  opacity: 0;
  visibility: hidden;
  transform: translateX(-50%) translateY(20px);
}

.voice-pulse {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background-color: var(--recording-color);
  animation: pulse 1.5s infinite;
}

.voice-text {
  font-size: 1.1rem;
  font-weight: 500;
}

@keyframes pulse {
  0% {
    transform: scale(1);
    opacity: 1;
  }
  50% {
    transform: scale(1.1);
    opacity: 0.7;
  }
  100% {
    transform: scale(1);
    opacity: 1;
  }
}

@keyframes bounce {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

@media (max-width: 900px) {
  .chat-area {
    flex-direction: column;
  }

  .topic-suggestions {
    width: 100%;
    max-height: 200px;
    margin-bottom: 15px;
  }

  .topic-btn {
    padding: 8px 12px;
  }
  
  .voice-indicator {
    bottom: 80px;
  }
}

@media (max-width: 768px) {
  body {
    padding: 10px;
    font-size: 16px;
  }
  
  .chat-container {
    height: 95vh;
    padding: 15px;
  }
  
  .message {
    font-size: 1.1rem;
    max-width: 90%;
    padding: 14px;
  }
  
  h1 {
    font-size: 1.8rem;
    margin-bottom: 15px;
  }
  
  #user-input, #send-btn {
    font-size: 1rem;
    padding: 12px;
  }
  
  .chat-area {
    margin-bottom: 15px;
  }
  
  .voice-text {
    font-size: 0.9rem;
  }
  
  .voice-pulse {
    width: 15px;
    height: 15px;
  }
  
  #send-btn {
    padding: 12px 15px;
  }
}