:root {
  --primary-color: #14b8a6;
  --secondary-color: #0f766e;
  --bg-color: #0f172a;
  --chat-bg: rgba(30, 41, 59, 0.7);
  --glass-border: rgba(255, 255, 255, 0.1);
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --message-me: linear-gradient(135deg, #0d9488, #2dd4bf);
  --message-other: rgba(51, 65, 85, 0.8);
  --error-color: #ef4444;
}

* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
  font-family:
    "Inter",
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Roboto,
    sans-serif;
}

body {
  background: var(--bg-color);
  background-image: radial-gradient(circle at top right, #1e293b 0%, #0f172a 100%);
  color: var(--text-primary);
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

/* App Wrapper */
.app-wrapper {
  display: flex;
  width: 100%;
  max-width: 1200px;
  height: 95vh;
  max-height: 900px;
  background: var(--chat-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  border-radius: 20px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
  overflow: hidden;
}

/* Sidebar */
.sidebar {
  width: 300px;
  background: rgba(15, 23, 42, 0.6);
  border-right: 1px solid var(--glass-border);
  display: flex;
  flex-direction: column;
  transition: transform 0.3s ease;
}

.sidebar-header {
  padding: 20px;
  border-bottom: 1px solid var(--glass-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.sidebar-header h2 {
  font-size: 1.2rem;
  font-weight: 600;
  background: var(--message-me);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Channels */
.sidebar-section {
  display: flex;
  flex-direction: column;
  border-bottom: 1px solid var(--glass-border);
}
.section-header {
  padding: 15px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.section-header h3 {
  font-size: 0.8rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1px;
}
.section-header button {
  background: transparent;
  border: none;
  color: var(--primary-color);
  cursor: pointer;
  font-size: 1.1rem;
  transition: transform 0.2s;
}
.section-header button:hover {
  transform: scale(1.1);
}
.channels-list {
  padding: 0 10px 15px 10px;
  max-height: 250px;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: rgba(255, 255, 255, 0.2) transparent;
}
.channel-item {
  padding: 10px 15px;
  border-radius: 8px;
  cursor: pointer;
  color: var(--text-secondary);
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: all 0.2s;
  margin-bottom: 5px;
}
.channel-item:hover {
  background: rgba(255, 255, 255, 0.05);
}
.channel-item.active {
  background: rgba(255, 255, 255, 0.1);
  color: var(--text-primary);
  font-weight: 600;
  border-left: 3px solid var(--primary-color);
}
.unread-badge {
  background: var(--error-color);
  color: white;
  font-size: 0.7rem;
  padding: 2px 6px;
  border-radius: 10px;
}

.online-users-container {
  flex: 1;
  padding: 15px 20px;
  overflow-y: auto;
  border-bottom: none;
}
.online-users-container h3 {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 15px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.online-user {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
  padding: 8px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.03);
  transition: background 0.2s;
}

.online-user:hover {
  background: rgba(255, 255, 255, 0.08);
}

.status-dot {
  width: 10px;
  height: 10px;
  background: #10b981;
  border-radius: 50%;
  box-shadow: 0 0 8px #10b981;
}

.user-controls {
  padding: 20px;
  border-top: 1px solid var(--glass-border);
  background: rgba(0, 0, 0, 0.2);
}

.btn-secondary {
  width: 100%;
  padding: 10px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  border-radius: 8px;
  cursor: pointer;
  margin-bottom: 10px;
  transition: all 0.2s;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
}

/* Chat Area */
.chat-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  position: relative;
}

.chat-header {
  padding: 15px 25px;
  border-bottom: 1px solid var(--glass-border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: rgba(0, 0, 0, 0.1);
}

.chat-title h3 {
  font-size: 1.1rem;
  font-weight: 600;
}

.chat-subtitle {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.hamburger {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 1.5rem;
  cursor: pointer;
}

/* Messages */
.messages-container {
  flex: 1;
  padding: 20px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 15px;
  scrollbar-width: thin;
  scrollbar-color: rgba(255, 255, 255, 0.2) transparent;
}

.messages-container::-webkit-scrollbar {
  width: 6px;
}
.messages-container::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.2);
  border-radius: 10px;
}

.message {
  max-width: 85%;
  display: flex;
  flex-direction: column;
  animation: slideIn 0.3s ease forwards;
}

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

.message.me {
  align-self: flex-end;
}

.message.other {
  align-self: flex-start;
}

/* Avatar styling */
.avatar {
  width: 36px;
  height: 36px;
  min-width: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 1.1rem;
  color: #fff;
  text-transform: uppercase;
  flex-shrink: 0;
}

.message-row {
  display: flex;
  align-items: flex-end;
  gap: 10px;
}
.message.me .message-row {
  flex-direction: row-reverse;
}

.message-sender {
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-bottom: 4px;
  margin-left: 4px;
}
.message.me .message-sender {
  display: none; /* Hide my own name */
}

/* Unsend button */
.msg-container-row {
  display: flex;
  align-items: center;
  gap: 8px;
}
.msg-delete-btn {
  background: transparent;
  border: none;
  color: var(--error-color);
  cursor: pointer;
  opacity: 0;
  transition: opacity 0.2s;
  padding: 8px;
  font-size: 1rem;
}
.message.me:hover .msg-delete-btn {
  opacity: 1;
}

.message-content {
  padding: 12px 16px;
  border-radius: 18px;
  font-size: 0.95rem;
  line-height: 1.4;
  word-wrap: break-word;
  position: relative;
}

.message.me .message-content {
  background: var(--message-me);
  border-bottom-right-radius: 4px;
}

.message.other .message-content {
  background: var(--message-other);
  border-bottom-left-radius: 4px;
  border: 1px solid var(--glass-border);
}

.message-content img {
  max-width: 100%;
  border-radius: 10px;
  margin-top: 5px;
  max-height: 300px;
  object-fit: contain;
  background: rgba(0, 0, 0, 0.2);
}

.message-content video {
  max-width: 100%;
  border-radius: 10px;
  margin-top: 5px;
  max-height: 300px;
  background: #000;
}

.message-content audio {
  width: 250px;
  max-width: 100%;
  height: 40px;
  outline: none;
  margin-top: 5px;
}

.download-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 10px;
  padding: 8px 12px;
  background: rgba(0, 0, 0, 0.2);
  border-radius: 8px;
  color: #fff;
  text-decoration: none;
  font-size: 0.85rem;
  transition: background 0.2s;
}
.download-link:hover {
  background: rgba(0, 0, 0, 0.4);
}

/* Typing & Upload Indicators */
.typing-indicator {
  font-size: 0.85rem;
  color: var(--primary-color);
  padding: 0 20px;
  height: 20px;
  font-style: italic;
  opacity: 0;
  transition: opacity 0.3s;
  flex-shrink: 0;
}
.typing-indicator.visible {
  opacity: 1;
}

/* Input Area */
.input-area {
  padding: 20px;
  background: rgba(0, 0, 0, 0.2);
  border-top: 1px solid var(--glass-border);
  display: flex;
  gap: 10px;
  align-items: center;
}

.input-area input[type="text"] {
  width: 0;
  min-width: 0;
  flex: 1;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--glass-border);
  padding: 14px 20px;
  border-radius: 25px;
  color: var(--text-primary);
  font-size: 0.95rem;
  outline: none;
  transition:
    border-color 0.2s,
    background 0.2s;
}

.input-area input[type="text"]:focus {
  border-color: var(--primary-color);
  background: rgba(255, 255, 255, 0.1);
}

.btn-action {
  width: 45px;
  height: 45px;
  min-width: 45px;
  border-radius: 50%;
  border: none;
  background: rgba(255, 255, 255, 0.1);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s;
  font-size: 1.1rem;
}

.btn-action:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: scale(1.05);
}

.btn-primary {
  background: var(--message-me);
}
.btn-primary:hover {
  transform: scale(1.05);
  box-shadow: 0 0 15px rgba(20, 184, 166, 0.4);
}

/* Recording Pulse */
.recording {
  background: var(--error-color) !important;
  animation: pulse 1.5s infinite;
}

@keyframes pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(239, 68, 68, 0.7);
  }
  70% {
    box-shadow: 0 0 0 15px rgba(239, 68, 68, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(239, 68, 68, 0);
  }
}

.hidden {
  display: none !important;
}

/* Modals */
.modal-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(10px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s;
}
.modal-overlay.active {
  opacity: 1;
  pointer-events: all;
}

.modal-content {
  background: var(--bg-color);
  padding: 30px;
  border-radius: 16px;
  width: 90%;
  max-width: 400px;
  border: 1px solid var(--glass-border);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
  transform: translateY(20px);
  transition: transform 0.3s;
}

.modal-overlay.active .modal-content {
  transform: translateY(0);
}

.modal-content h3 {
  margin-bottom: 20px;
  font-size: 1.3rem;
  text-align: center;
}

.form-group {
  margin-bottom: 15px;
}
.form-group label {
  display: block;
  margin-bottom: 8px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}
.form-group input {
  width: 100%;
  padding: 12px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--glass-border);
  border-radius: 8px;
  color: var(--text-primary);
  outline: none;
}
.form-group input:focus {
  border-color: var(--primary-color);
}

.btn-full {
  width: 100%;
  padding: 12px;
  border-radius: 8px;
  background: var(--message-me);
  color: white;
  border: none;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  margin-top: 10px;
  transition: opacity 0.2s;
}
.btn-full:hover {
  opacity: 0.9;
}

.text-error {
  color: var(--error-color);
  font-size: 0.85rem;
  margin-top: 5px;
  display: none;
}

/* Responsive */
@media (max-width: 768px) {
  .app-wrapper {
    height: 100svh;
    max-height: 100svh;
    border-radius: 0;
    border: none;
  }
  .sidebar {
    position: absolute;
    z-index: 50;
    height: 100%;
    transform: translateX(-100%);
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    width: 280px;
    box-shadow: 10px 0 20px rgba(0, 0, 0, 0.5);
  }
  .sidebar.mobile-open {
    transform: translateX(0);
  }
  .hamburger {
    display: block;
    margin-right: 15px;
  }

  .chat-header {
    padding: 10px 15px;
  }

  .input-area {
    padding: 10px;
    gap: 8px;
  }

  .btn-action {
    width: 40px;
    height: 40px;
    min-width: 40px;
    font-size: 1rem;
  }

  .input-area input[type="text"] {
    padding: 10px 15px;
    font-size: 0.9rem;
  }

  .message {
    max-width: 85%;
  }

  .message-content img,
  .message-content video {
    max-height: 200px;
  }
}