/* LYRIA Chat - Main Stylesheet */

/* ========================================
   CSS CUSTOM PROPERTIES (CSS VARIABLES)
   ======================================== */
:root {
  /* Color Palette */
  --primary-color: #36393f;
  --secondary-color: #5865f2;
  --accent-color: #43b581;
  --text-color: #dcddde;
  --text-muted: #8e9297;
  --background-color: #2f3136;
  --background-light: #32353b;
  --channel-hover: #42464d;
  --message-hover: #32353b;
  --sidebar-color: #202225;
  --header-color: #2b2d3e;
  --error-color: #e74c3c;
  --success-color: #2ecc71;
  --warning-color: #f39c12;
  
  /* Layout */
  --sidebar-width: 250px;
  --header-height: 80px;
  --border-radius: 8px;
  --border-radius-small: 4px;
  
  /* Typography */
  --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, Arial, sans-serif;
  --font-size-small: 0.9rem;
  --font-size-base: 1rem;
  --font-size-large: 1.2rem;
  --font-size-xl: 1.5rem;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  
  /* Shadows */
  --shadow-light: 0 2px 4px rgba(0, 0, 0, 0.1);
  --shadow-medium: 0 4px 8px rgba(0, 0, 0, 0.2);
  --shadow-heavy: 0 8px 16px rgba(0, 0, 0, 0.3);
  
  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;
  
  /* Z-index levels */
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-fixed: 300;
  --z-modal: 1000;
  --z-tooltip: 2000;
}

/* Dark mode overrides */
.dark-mode {
  --text-color: #ffffff;
  --background-color: #1a1a1a;
  --primary-color: #2d2d2d;
  --sidebar-color: #1e1e1e;
}

/* ========================================
   RESET AND BASE STYLES
   ======================================== */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  background-color: var(--primary-color);
  color: var(--text-color);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Improve focus visibility */
*:focus {
  outline: 2px solid var(--secondary-color);
  outline-offset: 2px;
}

/* ========================================
   UTILITY CLASSES
   ======================================== */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.loading {
  opacity: 0.7;
  pointer-events: none;
}

.error-text {
  color: var(--error-color);
  font-size: var(--font-size-small);
}

.success-text {
  color: var(--success-color);
  font-size: var(--font-size-small);
}

.text-muted {
  color: var(--text-muted);
}

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.hidden { display: none !important; }
.visible { display: block !important; }

/* ========================================
   LAYOUT - LANDING PAGE (index.html)
   ======================================== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-md);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-lg) 0;
  border-bottom: 1px solid var(--background-light);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.logo img {
  width: 40px;
  height: 40px;
  border-radius: 50%;
}

.logo h1 {
  font-size: var(--font-size-xl);
  font-weight: bold;
  color: var(--text-color);
}

nav {
  display: flex;
  gap: var(--spacing-md);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--border-radius-small);
  text-decoration: none;
  font-weight: 500;
  font-size: var(--font-size-base);
  transition: all var(--transition-base);
  cursor: pointer;
  border: 2px solid transparent;
  min-width: 120px;
}

.btn:focus {
  outline: 2px solid var(--secondary-color);
  outline-offset: 2px;
}

.btn.primary {
  background-color: var(--secondary-color);
  color: white;
  border-color: var(--secondary-color);
}

.btn.primary:hover {
  background-color: #4752c4;
  transform: translateY(-1px);
  box-shadow: var(--shadow-medium);
}

.btn.secondary {
  background-color: transparent;
  color: var(--text-color);
  border-color: var(--text-muted);
}

.btn.secondary:hover {
  background-color: var(--background-light);
  border-color: var(--text-color);
}

/* Hero Section */
.hero {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: var(--spacing-xl) 0;
}

.hero h2 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  margin-bottom: var(--spacing-md);
  background: linear-gradient(135deg, var(--secondary-color), var(--accent-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: var(--font-size-large);
  color: var(--text-muted);
  margin-bottom: var(--spacing-xl);
  max-width: 600px;
}

/* Features */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
  width: 100%;
  max-width: 1000px;
}

.feature {
  background: var(--background-light);
  padding: var(--spacing-xl);
  border-radius: var(--border-radius);
  text-align: center;
  transition: transform var(--transition-base);
  border: 1px solid var(--channel-hover);
}

.feature:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-medium);
}

.feature img {
  width: 64px;
  height: 64px;
  margin-bottom: var(--spacing-md);
  border-radius: var(--border-radius-small);
}

.feature h3 {
  font-size: var(--font-size-large);
  margin-bottom: var(--spacing-sm);
  color: var(--text-color);
}

.feature p {
  color: var(--text-muted);
  line-height: 1.6;
}

/* CTA Buttons */
.cta-buttons {
  display: flex;
  gap: var(--spacing-md);
  flex-wrap: wrap;
  justify-content: center;
}

/* Footer */
footer {
  text-align: center;
  padding: var(--spacing-lg) 0;
  border-top: 1px solid var(--background-light);
  color: var(--text-muted);
  font-size: var(--font-size-small);
}

/* ========================================
   LAYOUT - CHAT APPLICATION
   ======================================== */
.top-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background-color: var(--header-color);
  color: var(--text-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--spacing-md);
  box-shadow: var(--shadow-medium);
  z-index: var(--z-fixed);
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-color);
  font-size: var(--font-size-xl);
  cursor: pointer;
  padding: var(--spacing-sm);
  border-radius: var(--border-radius-small);
  transition: background-color var(--transition-base);
}

.menu-toggle:hover {
  background-color: var(--channel-hover);
}

.app-container {
  display: flex;
  height: calc(100vh - var(--header-height));
  margin-top: var(--header-height);
  background-color: var(--background-color);
}

/* ========================================
   SIDEBAR
   ======================================== */
.sidebar {
  width: var(--sidebar-width);
  background-color: var(--sidebar-color);
  display: flex;
  flex-direction: column;
  height: 100%;
  transition: transform var(--transition-base);
  position: relative;
  z-index: var(--z-sticky);
}

.sidebar.open {
  transform: translateX(0);
}

/* Channels Section */
.channels {
  flex: 1;
  padding: var(--spacing-md);
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--channel-hover) transparent;
}

.channels::-webkit-scrollbar {
  width: 8px;
}

.channels::-webkit-scrollbar-track {
  background: transparent;
}

.channels::-webkit-scrollbar-thumb {
  background-color: var(--channel-hover);
  border-radius: 4px;
}

.channels h3 {
  font-size: var(--font-size-small);
  color: var(--text-muted);
  margin-bottom: var(--spacing-md);
  text-transform: uppercase;
  font-weight: 600;
  letter-spacing: 0.5px;
}

.channels-list {
  list-style: none;
  margin-bottom: var(--spacing-lg);
}

.channel-btn {
  display: flex;
  align-items: center;
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  background: none;
  border: none;
  color: var(--text-muted);
  text-align: left;
  border-radius: var(--border-radius-small);
  transition: all var(--transition-fast);
  cursor: pointer;
  font-size: var(--font-size-base);
  position: relative;
}

.channel-btn:hover,
.channel-btn.active {
  background-color: var(--channel-hover);
  color: var(--text-color);
}

.channel-btn::before {
  content: '#';
  margin-right: var(--spacing-sm);
  color: var(--text-muted);
}

.unread-count {
  background: var(--error-color);
  color: white;
  border-radius: 50%;
  padding: 2px 6px;
  font-size: 0.75rem;
  margin-left: auto;
  min-width: 18px;
  text-align: center;
}

/* Action Buttons */
.add-channel-btn,
.join-channel-btn,
.leave-channel-btn,
.action-btn {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  background-color: var(--background-color);
  color: var(--text-muted);
  border: 1px solid var(--channel-hover);
  border-radius: var(--border-radius-small);
  cursor: pointer;
  transition: all var(--transition-fast);
  font-size: var(--font-size-small);
  margin-bottom: var(--spacing-sm);
}

.add-channel-btn:hover,
.join-channel-btn:hover,
.action-btn:hover {
  background-color: var(--channel-hover);
  color: var(--text-color);
  border-color: var(--secondary-color);
}

.leave-channel-btn:hover {
  background-color: var(--error-color);
  color: white;
  border-color: var(--error-color);
}

/* User Profile */
.user-profile {
  padding: var(--spacing-md);
  background-color: var(--background-light);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  border-top: 1px solid var(--channel-hover);
}

.avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 2px solid var(--secondary-color);
  object-fit: cover;
  cursor: pointer;
  transition: transform var(--transition-fast);
}

.avatar:hover {
  transform: scale(1.05);
}

.username {
  flex: 1;
  font-weight: 600;
  color: var(--text-color);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  cursor: pointer;
}

.settings-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: var(--spacing-xs);
  border-radius: var(--border-radius-small);
  transition: all var(--transition-fast);
  font-size: var(--font-size-large);
}

.settings-btn:hover {
  color: var(--secondary-color);
  background-color: var(--channel-hover);
  transform: rotate(15deg);
}

/* ========================================
   CHAT AREA
   ======================================== */
.chat-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  height: 100%;
  min-width: 0; /* Allows flex shrinking */
}

.chat-header {
  padding: var(--spacing-md);
  background-color: var(--background-light);
  border-bottom: 1px solid var(--channel-hover);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-shrink: 0;
}

.chat-header h2 {
  font-size: var(--font-size-large);
  color: var(--text-color);
  margin: 0;
}

/* Messages */
.messages {
  flex: 1;
  padding: var(--spacing-md);
  overflow-y: auto;
  background-color: var(--background-color);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.message {
  background-color: var(--background-light);
  padding: var(--spacing-md);
  border-radius: var(--border-radius);
  border-left: 3px solid var(--secondary-color);
  transition: transform var(--transition-fast);
  position: relative;
}

.message:hover {
  transform: translateX(2px);
  box-shadow: var(--shadow-light);
}

.message-header {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-xs);
}

.message-header strong {
  color: var(--secondary-color);
  font-weight: 600;
}

.timestamp {
  color: var(--text-muted);
  font-size: var(--font-size-small);
  margin-left: auto;
}

.message-content {
  color: var(--text-color);
  line-height: 1.5;
  word-wrap: break-word;
}

/* Message Input */
.message-input {
  display: flex;
  align-items: flex-end;
  padding: var(--spacing-md);
  background-color: var(--background-light);
  border-top: 1px solid var(--channel-hover);
  gap: var(--spacing-sm);
}

.message-input textarea {
  flex: 1;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--border-radius);
  border: 1px solid var(--channel-hover);
  background-color: var(--background-color);
  color: var(--text-color);
  resize: none;
  min-height: 40px;
  max-height: 120px;
  font-family: inherit;
  font-size: var(--font-size-base);
  transition: border-color var(--transition-fast);
}

.message-input textarea:focus {
  border-color: var(--secondary-color);
  outline: none;
}

.message-input textarea::placeholder {
  color: var(--text-muted);
}

.send-btn {
  background-color: var(--secondary-color);
  color: white;
  border: none;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--border-radius);
  cursor: pointer;
  font-weight: 600;
  transition: all var(--transition-fast);
  min-width: 80px;
}

.send-btn:hover {
  background-color: #4752c4;
  transform: translateY(-1px);
}

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

/* ========================================
   MODALS
   ======================================== */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: var(--z-modal);
  backdrop-filter: blur(4px);
}

.modal-backdrop {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.7);
  cursor: pointer;
}

.modal-content {
  background-color: var(--background-color);
  margin: 5% auto;
  padding: var(--spacing-xl);
  border: 1px solid var(--channel-hover);
  border-radius: var(--border-radius);
  width: 90%;
  max-width: 500px;
  max-height: 80vh;
  overflow-y: auto;
  position: relative;
  box-shadow: var(--shadow-heavy);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}

.close-button {
  position: absolute;
  top: var(--spacing-md);
  right: var(--spacing-md);
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: var(--font-size-xl);
  cursor: pointer;
  padding: var(--spacing-xs);
  border-radius: var(--border-radius-small);
  transition: all var(--transition-fast);
}

.close-button:hover {
  color: var(--error-color);
  background-color: var(--background-light);
}

/* ========================================
   FORMS
   ======================================== */
.modal-section {
  margin-bottom: var(--spacing-lg);
}

.modal-label {
  display: block;
  margin-bottom: var(--spacing-sm);
  color: var(--text-color);
  font-weight: 500;
}

.modal-input {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1px solid var(--channel-hover);
  border-radius: var(--border-radius-small);
  background-color: var(--background-light);
  color: var(--text-color);
  font-size: var(--font-size-base);
  transition: border-color var(--transition-fast);
}

.modal-input:focus {
  outline: none;
  border-color: var(--secondary-color);
  box-shadow: 0 0 0 2px rgba(88, 101, 242, 0.2);
}

.modal-input::placeholder {
  color: var(--text-muted);
}

/* Toggle Switch */
.toggle-switch {
  position: relative;
  display: inline-flex;
  align-items: center;
  cursor: pointer;
  gap: var(--spacing-sm);
}

.toggle-switch input[type="checkbox"] {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  position: relative;
  width: 44px;
  height: 24px;
  background-color: var(--channel-hover);
  border-radius: 24px;
  transition: background-color var(--transition-base);
}

.slider::before {
  content: '';
  position: absolute;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background-color: white;
  top: 2px;
  left: 2px;
  transition: transform var(--transition-base);
}

.toggle-switch input:checked + .slider {
  background-color: var(--secondary-color);
}

.toggle-switch input:checked + .slider::before {
  transform: translateX(20px);
}

/* ========================================
   RESPONSIVE DESIGN
   ======================================== */
@media (max-width: 768px) {
  .menu-toggle {
    display: block;
  }
  
  .sidebar {
    position: fixed;
    top: var(--header-height);
    left: 0;
    height: calc(100vh - var(--header-height));
    transform: translateX(-100%);
    z-index: var(--z-fixed);
    box-shadow: var(--shadow-heavy);
  }
  
  .sidebar.open {
    transform: translateX(0);
  }
  
  .app-container {
    padding-left: 0;
  }
  
  .features {
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
  }
  
  .cta-buttons {
    flex-direction: column;
    align-items: center;
  }
  
  .btn {
    width: 100%;
    max-width: 300px;
  }
  
  header {
    padding: var(--spacing-md) 0;
  }
  
  nav {
    gap: var(--spacing-sm);
  }
  
  .modal-content {
    width: 95%;
    margin: 10% auto;
    padding: var(--spacing-md);
  }
}

@media (max-width: 480px) {
  .hero h2 {
    font-size: 2rem;
  }
  
  .hero-subtitle {
    font-size: var(--font-size-base);
  }
  
  .feature {
    padding: var(--spacing-md);
  }
  
  .message-input {
    flex-direction: column;
    align-items: stretch;
  }
  
  .send-btn {
    margin-top: var(--spacing-sm);
  }
}

/* ========================================
   PRINT STYLES
   ======================================== */
@media print {
  .sidebar,
  .message-input,
  .modal {
    display: none !important;
  }
  
  .chat-area {
    width: 100% !important;
  }
  
  .message {
    break-inside: avoid;
  }
}

/* ========================================
   ANIMATIONS AND LOADING STATES
   ======================================== */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInFromLeft {
  from { transform: translateX(-100%); }
  to { transform: translateX(0); }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.fade-in {
  animation: fadeIn 0.3s ease-out;
}

.slide-in {
  animation: slideInFromLeft 0.3s ease-out;
}

.loading-pulse {
  animation: pulse 1.5s infinite;
}

/* Loading spinner */
.spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 2px solid var(--text-muted);
  border-radius: 50%;
  border-top-color: var(--secondary-color);
  animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ========================================
   ACCESSIBILITY IMPROVEMENTS
   ======================================== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* High contrast mode */
@media (prefers-contrast: high) {
  :root {
    --background-color: #000000;
    --text-color: #ffffff;
    --border-color: #ffffff;
  }
}

/* Focus indicators for keyboard navigation */
.keyboard-focus *:focus {
  outline: 3px solid var(--secondary-color) !important;
  outline-offset: 2px !important;
}