:root {
  /* Primary */
  --primary: #006d2f;
  --primary-container: #25d366;
  --on-primary: #ffffff;
  --on-primary-container: #005523;
  --primary-fixed: #66ff8e;
  --primary-fixed-dim: #3de273;
  --inverse-primary: #3de273;
  
  /* Secondary */
  --secondary: #1c695f;
  --secondary-container: #a5ede0;
  --on-secondary: #ffffff;
  --on-secondary-container: #226e63;
  
  /* Tertiary */
  --tertiary: #00668a;
  --tertiary-container: #48c4ff;
  --on-tertiary: #ffffff;
  
  /* Error */
  --error: #ba1a1a;
  --error-container: #ffdad6;
  --on-error: #ffffff;
  --on-error-container: #93000a;
  
  /* Surface */
  --surface: #f7f9fc;
  --surface-dim: #d8dadd;
  --surface-bright: #f7f9fc;
  --surface-container-lowest: #ffffff;
  --surface-container-low: #f2f4f7;
  --surface-container: #eceef1;
  --surface-container-high: #e6e8eb;
  --surface-container-highest: #e0e3e6;
  --surface-variant: #e0e3e6;
  --surface-tint: #006d2f;
  --on-surface: #191c1e;
  --on-surface-variant: #3c4a3d;
  --inverse-surface: #2d3133;
  --inverse-on-surface: #eff1f4;
  
  /* Outline */
  --outline: #6c7b6b;
  --outline-variant: #bbcbb9;
  
  /* Background */
  --background: #f7f9fc;
  --on-background: #191c1e;
  
  /* Chat */
  --chat-bg: #E5DDD5;
  --bubble-outgoing: #D9FDD3;
  --bubble-incoming: #ffffff;
  --read-receipt: #53bdeb;
  
  /* Spacing */
  --space-xxs: 0.25rem;
  --space-xs: 0.5rem;
  --space-sm: 0.75rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --layout-margin: 1rem;
  --bubble-padding-h: 0.75rem;
  --bubble-padding-v: 0.5rem;
  
  /* Typography */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  
  /* Rounded */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07);
  --shadow-lg: 0 4px 12px rgba(0,0,0,0.1);
  --shadow-xl: 0 8px 24px rgba(0,0,0,0.12);
  
  /* Transitions */
  --transition-fast: 100ms ease;
  --transition-normal: 200ms ease;
  --transition-slow: 300ms ease-in-out;
}

[data-theme="dark"] {
  --primary: #3de273;
  --primary-container: #005322;
  --on-primary: #003913;
  --on-primary-container: #66ff8e;
  --secondary: #8cd4c7;
  --secondary-container: #005047;
  --on-secondary: #003730;
  --on-secondary-container: #a8f0e3;
  --tertiary: #7cd0ff;
  --tertiary-container: #004c69;
  --surface: #1a1c1e;
  --surface-dim: #111315;
  --surface-bright: #383a3c;
  --surface-container-lowest: #0e1012;
  --surface-container-low: #1e2022;
  --surface-container: #232527;
  --surface-container-high: #2d2f31;
  --surface-container-highest: #383a3c;
  --surface-variant: #414942;
  --on-surface: #e3e2e6;
  --on-surface-variant: #c1c9be;
  --outline: #8b9b89;
  --outline-variant: #414942;
  --background: #1a1c1e;
  --on-background: #e3e2e6;
  --inverse-surface: #e3e2e6;
  --inverse-on-surface: #2d3133;
  --error: #ffb4ab;
  --error-container: #93000a;
  --chat-bg: #0b141a;
  --bubble-outgoing: #005c4b;
  --bubble-incoming: #202c33;
}

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

body {
  font-family: var(--font-family);
  background-color: var(--background);
  color: var(--on-surface);
  min-height: 100vh;
  overflow-x: hidden;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

::selection {
  background-color: var(--primary);
  color: var(--on-primary);
}

::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--outline-variant);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--outline);
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--primary-container);
}

:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}

/* Typography Classes */
.text-headline-lg { font-size: 22px; line-height: 28px; font-weight: 600; }
.text-headline-md { font-size: 18px; line-height: 24px; font-weight: 600; }
.text-body-lg { font-size: 16px; line-height: 24px; font-weight: 400; }
.text-body-md { font-size: 14px; line-height: 20px; font-weight: 400; }
.text-label-lg { font-size: 14px; line-height: 20px; font-weight: 500; }
.text-label-md { font-size: 12px; line-height: 16px; font-weight: 500; letter-spacing: 0.02em; }
.text-label-sm { font-size: 11px; line-height: 14px; font-weight: 400; }

/* App Shell */
.app-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-xs) var(--layout-margin);
  background-color: rgba(var(--surface-rgb), 0.9);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 50;
  box-shadow: var(--shadow-sm);
  height: 56px;
}

.app-header__title {
  font-size: 22px;
  line-height: 28px;
  font-weight: 800;
  color: var(--primary);
}

.app-header__actions {
  display: flex;
  gap: var(--space-xs);
}

.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-around;
  background-color: var(--surface-container-lowest);
  box-shadow: 0 -1px 2px rgba(0,0,0,0.05);
  z-index: 50;
  padding: var(--space-xs) 0;
  padding-bottom: calc(var(--space-xs) + env(safe-area-inset-bottom));
}

.bottom-nav__item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: var(--space-xs) var(--space-md);
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition-normal);
  color: var(--on-surface-variant);
}

.bottom-nav__item--active {
  background-color: var(--secondary-container);
  color: var(--on-secondary-container);
}

.bottom-nav__item .icon {
  font-size: 24px;
}

.bottom-nav__item .label {
  font-size: 12px;
  line-height: 16px;
  font-weight: 500;
  letter-spacing: 0.02em;
}

.content-area {
  padding-top: 56px;
  padding-bottom: calc(64px + env(safe-area-inset-bottom));
  min-height: 100vh;
}

/* Chat List */
.chat-list {
  display: flex;
  flex-direction: column;
}

.chat-item {
  display: flex;
  align-items: center;
  padding: var(--space-sm) var(--layout-margin);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.chat-item:hover {
  background-color: var(--surface-container-high);
}

.chat-item:active {
  background-color: var(--surface-container-highest);
  transform: scale(0.99);
}

.chat-item__avatar-wrapper {
  position: relative;
  flex-shrink: 0;
}

.chat-item__avatar {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-full);
  object-fit: cover;
  border: none;
}

.chat-item__online-dot {
  position: absolute;
  bottom: 0;
  right: 0;
  width: 14px;
  height: 14px;
  background-color: var(--primary);
  border-radius: var(--radius-full);
  border: 2px solid var(--surface);
}

.chat-item__content {
  flex-grow: 1;
  margin-left: var(--space-md);
  border-bottom: 1px solid var(--surface-variant);
  padding-bottom: var(--space-sm);
  min-width: 0;
}

.chat-item:last-child .chat-item__content {
  border-bottom: none;
}

.chat-item__header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 2px;
}

.chat-item__name {
  font-size: 16px;
  line-height: 24px;
  font-weight: 600;
  color: var(--on-surface);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.chat-item__time {
  font-size: 12px;
  line-height: 16px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--on-surface-variant);
  flex-shrink: 0;
}

.chat-item__time.unread {
  color: var(--primary);
}

.chat-item__preview {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.chat-item__message {
  font-size: 14px;
  line-height: 20px;
  font-weight: 400;
  color: var(--on-surface-variant);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: calc(100% - 40px);
}

.chat-item__badge {
  background-color: var(--primary);
  color: var(--on-primary);
  font-size: 11px;
  font-weight: 600;
  min-width: 20px;
  text-align: center;
  border-radius: var(--radius-full);
  padding: 2px 6px;
  flex-shrink: 0;
}

/* Chat Window */
.chat-window {
  display: flex;
  flex-direction: column;
  flex: 1;
  overflow: hidden;
  height: 100vh;
}

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: var(--layout-margin);
  background-color: var(--chat-bg);
  position: relative;
  display: flex;
  flex-direction: column;
}

.chat-messages__pattern {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  opacity: 0.05;
  pointer-events: none;
  background-image: url('data:image/svg+xml;utf8,<svg width="20" height="20" xmlns="http://www.w3.org/2000/svg"><circle cx="2" cy="2" r="1.5" fill="%23000"/></svg>');
}

.chat-messages__container {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  max-width: 768px;
  margin: 0 auto;
  width: 100%;
  padding-bottom: var(--space-lg);
}

.message {
  display: flex;
  max-width: 80%;
  width: max-content;
}

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

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

.message__bubble {
  padding: var(--bubble-padding-v) var(--bubble-padding-h);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast);
  position: relative;
}

.message__bubble:hover {
  transform: scale(1.01);
}

.message--incoming .message__bubble {
  background-color: var(--bubble-incoming);
  color: var(--on-surface);
  border-top-left-radius: 4px;
}

.message--outgoing .message__bubble {
  background-color: var(--bubble-outgoing);
  color: var(--on-surface);
  border-top-right-radius: 4px;
}

.message__text {
  font-size: 14px;
  line-height: 1.5;
  word-break: break-word;
}

.message__meta {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: 4px;
  margin-top: 4px;
  min-width: 60px;
}

.message__time {
  font-size: 11px;
  opacity: 0.7;
}

.message__status {
  font-size: 14px;
}

.message__status--sent {
  color: var(--on-surface-variant);
}

.message__status--delivered {
  color: var(--on-surface-variant);
}

.message__status--read {
  color: var(--read-receipt);
}

.date-separator {
  display: flex;
  justify-content: center;
  margin: var(--space-md) 0;
}

.date-separator__chip {
  background-color: var(--surface-container);
  color: var(--on-surface-variant);
  padding: 4px 12px;
  border-radius: var(--radius-lg);
  font-size: 12px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  box-shadow: var(--shadow-sm);
}

.consecutive-message {
  margin-top: -4px;
}

.consecutive-message.message--incoming .message__bubble {
  border-top-left-radius: var(--radius-xl);
}

.consecutive-message.message--outgoing .message__bubble {
  border-top-right-radius: var(--radius-xl);
}

/* Typing Indicator */
.typing-indicator {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: var(--space-xs) var(--space-sm);
  align-self: flex-start;
}

.typing-indicator__dot {
  width: 8px;
  height: 8px;
  border-radius: var(--radius-full);
  background-color: var(--on-surface-variant);
  opacity: 0.4;
  animation: typing-bounce 1.4s infinite ease-in-out both;
}

.typing-indicator__dot:nth-child(1) { animation-delay: -0.32s; }
.typing-indicator__dot:nth-child(2) { animation-delay: -0.16s; }

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

/* Message Input Bar */
.message-composer {
  background-color: var(--surface);
  border-top: 1px solid rgba(var(--outline-variant-rgb), 0.2);
  padding: var(--space-xs) var(--layout-margin);
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  z-index: 50;
  padding-bottom: calc(var(--space-xs) + env(safe-area-inset-bottom));
}

.message-composer__actions {
  display: flex;
  align-items: center;
  gap: 2px;
}

.message-composer__input-wrapper {
  flex: 1;
  background-color: var(--surface-container-low);
  border-radius: var(--radius-full);
  padding: var(--space-xs) var(--space-md);
  display: flex;
  align-items: center;
  min-height: 48px;
}

.message-composer__input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  font-size: 14px;
  color: var(--on-surface);
  max-height: 100px;
  resize: none;
  overflow-y: auto;
}

.message-composer__input::placeholder {
  color: rgba(var(--on-surface-variant-rgb), 0.6);
}

.message-composer__send {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-full);
  background-color: var(--primary);
  color: var(--on-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast);
  border: none;
  cursor: pointer;
  flex-shrink: 0;
}

.message-composer__send:active {
  transform: scale(0.9);
}

/* Icon Buttons */
.icon-btn {
  padding: 8px;
  border-radius: var(--radius-full);
  background: transparent;
  color: var(--on-surface-variant);
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
}

.icon-btn:hover {
  background-color: var(--surface-container-high);
}

.icon-btn:active {
  transform: scale(0.95);
}

.icon-btn--primary {
  color: var(--primary);
}

/* FAB */
.fab {
  position: fixed;
  bottom: calc(64px + var(--space-md) + env(safe-area-inset-bottom));
  right: var(--space-lg);
  width: 56px;
  height: 56px;
  background-color: var(--primary-container);
  color: var(--on-primary-container);
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 40;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
}

.fab:hover {
  background-color: var(--primary-fixed);
  box-shadow: var(--shadow-xl);
  transform: scale(1.05);
}

.fab:active {
  transform: scale(0.9);
}

.fab .material-symbols-outlined {
  font-size: 28px;
  font-variation-settings: 'FILL' 1;
}

/* Auth Pages */
.auth-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--surface);
  padding: var(--space-lg);
}

.auth-card {
  width: 100%;
  max-width: 420px;
  background-color: var(--surface-container-lowest);
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-xl);
  padding: var(--space-xl);
  position: relative;
  overflow: hidden;
}

.auth-card__gradient {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(to right, var(--primary), var(--primary-container));
}

.form-group {
  margin-bottom: var(--space-md);
}

.form-label {
  display: block;
  font-size: 12px;
  font-weight: 500;
  color: var(--on-surface);
  margin-bottom: var(--space-xxs);
}

.form-input {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--outline-variant);
  border-radius: var(--radius-lg);
  font-size: 14px;
  background-color: var(--surface-container-lowest);
  color: var(--on-surface);
  transition: all var(--transition-fast);
  outline: none;
}

.form-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(var(--primary-rgb), 0.1);
}

.btn {
  padding: 12px 24px;
  border-radius: var(--radius-lg);
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
}

.btn--primary {
  background-color: var(--primary);
  color: var(--on-primary);
}

.btn--primary:hover {
  background-color: var(--primary-container);
  color: var(--on-primary-container);
  box-shadow: var(--shadow-md);
}

.btn--full {
  width: 100%;
}

/* Explore Grid */
.ai-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-md);
  padding: 0 var(--layout-margin);
}

@media (min-width: 768px) {
  .ai-grid { grid-template-columns: repeat(3, 1fr); }
}
@media (min-width: 1024px) {
  .ai-grid { grid-template-columns: repeat(4, 1fr); }
}

.ai-card {
  background-color: var(--surface-container-lowest);
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
  border: 1px solid var(--surface-variant);
}

.ai-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
  border-color: rgba(var(--primary-rgb), 0.3);
}

.ai-card__avatar {
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
}

.ai-card__body {
  padding: var(--space-sm);
}

/* Animations */
@keyframes fadeIn {
  0% { opacity: 0; transform: translateY(10px); }
  100% { opacity: 1; transform: translateY(0); }
}

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

/* Utilities */
.truncate {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.hidden {
  display: none !important;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Profile Page */
.profile-hero {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--space-lg);
    background-color: var(--surface-container-lowest);
    box-shadow: var(--shadow-sm);
}
.profile-hero__avatar {
    width: 160px;
    height: 160px;
    border-radius: var(--radius-full);
    object-fit: cover;
    border: 4px solid var(--surface);
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-fast);
}
.profile-hero__avatar:hover {
    transform: scale(1.05);
}
.profile-hero__name {
    font-size: 22px;
    font-weight: bold;
    margin-top: var(--space-md);
}

/* Settings */
.settings-menu-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-xxs);
}
.settings-menu-item {
    display: flex;
    align-items: center;
    padding: var(--space-md) var(--layout-margin);
    cursor: pointer;
    transition: background-color var(--transition-fast);
}
.settings-menu-item:hover {
    background-color: rgba(0, 109, 47, 0.04);
}
.settings-menu-item__icon {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    background-color: var(--surface-container-high);
    color: var(--on-surface-variant);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}
.settings-menu-item:hover .settings-menu-item__icon {
    background-color: var(--primary-container);
    color: var(--on-primary-container);
}