body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  margin: 0;
  padding: 0;
  background-color: var(--page-bg);
  color: var(--text-color);
  overflow-x: hidden;
  scrollbar-gutter: stable both-edges;
}

body::before {
  content: 'cloud_upload';
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) scale(0.98);
  text-align: center;
  font-family: 'Material Symbols Rounded';
  font-variation-settings: 'FILL' 1, 'wght' 300, 'GRAD' 0, 'opsz' 72;
  font-size: 84px;
  color: var(--text-color);
  z-index: 1001;
  pointer-events: none;
  opacity: 0;
  transition: opacity 180ms ease, transform 180ms ease;
}

body.drag-over::before {
  opacity: 1;
  transform: translate(-50%, -50%) scale(1);
  color: var(--primary-color);
  animation: drag-pulse 1.2s ease-in-out infinite;
}

.drag-over-text {
  position: fixed;
  top: calc(50% + 60px);
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  font-weight: 700;
  font-size: 22px;
  color: var(--text-color);
  z-index: 1001;
  pointer-events: none;
  opacity: 0;
  transition: opacity 180ms ease;
}

body.drag-over .drag-over-text {
  opacity: 1;
}

.main-container::after {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.1);
  z-index: 1000;
  pointer-events: none;
  opacity: 0;
  transition: opacity 150ms ease;
}

body[color-scheme="dark"] .main-container::after {
  background: rgba(0, 0, 0, 0.35);
  -webkit-backdrop-filter: blur(4px);
  backdrop-filter: blur(4px);
}

body[color-scheme="light"] .main-container::after {
  background: rgba(0, 0, 0, 0.18);
  -webkit-backdrop-filter: blur(4px);
  backdrop-filter: blur(4px);
}

body.drag-over .main-container::after {
  opacity: 1;
}

@keyframes drag-pulse {
  0% {
    transform: translate(-50%, -50%) scale(1);
    text-shadow: 0 0 0 rgba(0, 0, 0, 0);
  }
  50% {
    transform: translate(-50%, -50%) scale(1.08);
    text-shadow: 0 4px 16px rgba(0, 0, 0, 0.12);
  }
  100% {
    transform: translate(-50%, -50%) scale(1);
    text-shadow: 0 0 0 rgba(0, 0, 0, 0);
  }
}

button {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  font-size: 16px;
  margin: 0;
  padding: 0;
  background-color: var(--button-bg);
  border-radius: 8px;
  padding: var(--one);
  color: var(--button-text);
  border: none;
  cursor: pointer;
}

button:hover, button:active {
  background-color: var(--button-bg-hover);
}

button:focus {
  outline: none;
  box-shadow: 0 0 0 2px var(--focus-ring);
}

select {
  padding: var(--half) var(--half);
  border-radius: var(--half);
  background-color: transparent;
  color: var(--text-color);
  cursor: pointer;
  min-width: 200px;
  position: relative;
  padding-right: 30px;
  padding-right: 30px;
}

select:hover {
  background-color: var(--tile-bg);
}

select:focus {
  outline: none;
  box-shadow: 0 0 0 2px var(--focus-ring);
}

select::-ms-expand {
  display: none;
}

select option {
  padding: var(--half);
  background-color: var(--tile-bg);
  color: var(--text-color);
}

h1, h2, h3, h4, h5, h6 {
  color: var(--primary-color);
}

pre {
  white-space: pre-wrap;
  word-wrap: break-word;
  background-color: var(--code-bg);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  padding: 10px;
  margin: 10px 0;
  overflow-x: auto;
}

code {
  font-family: 'Courier New', Courier, monospace;
  font-size: 0.9em;
}

.material-symbols-outlined, .material-symbols-rounded, .material-icons {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  vertical-align: middle;
  font-weight: normal;
  font-style: normal;
  letter-spacing: normal;
  text-transform: none;
  white-space: nowrap;
  direction: ltr;
  -webkit-font-feature-settings: 'liga';
  font-feature-settings: 'liga';
  -webkit-font-smoothing: antialiased;
  line-height: 1;
  font-size: 24px;
}

.qestit-button:not(.active) svg {
  fill: #fff;
}

body[color-scheme="light"] .qestit-button:not(.active) svg {
  fill: var(--primary-color);
}

.qestit-button.active svg {
  fill: var(--primary-color);
}

.chatBox, .sidebar, textarea {
  scrollbar-color: var(--border-color) transparent;
  scrollbar-width: thin;
  overflow-y: auto;
  scrollbar-gutter: stable;
}

.chatBox::-webkit-scrollbar, .sidebar::-webkit-scrollbar, textarea::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

.chatBox::-webkit-scrollbar-track, .sidebar::-webkit-scrollbar-track, textarea::-webkit-scrollbar-track {
  background: transparent;
}

.chatBox::-webkit-scrollbar-thumb, .sidebar::-webkit-scrollbar-thumb, textarea::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: 4px;
}

.chatBox::-webkit-scrollbar-thumb:hover, .sidebar::-webkit-scrollbar-thumb:hover, textarea::-webkit-scrollbar-thumb:hover {
  background: var(--primary-color);
}

.left-nav {
  scrollbar-color: var(--border-color) transparent;
  scrollbar-width: none;
  overflow-y: auto;
}

.left-nav::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

.left-nav::-webkit-scrollbar-track {
  background: transparent;
}

.left-nav::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: 4px;
}

.left-nav::-webkit-scrollbar-thumb:hover {
  background: var(--primary-color);
}

.hidden {
  display: none !important;
}