:root {
  --text: #333;
  --accent: #007bff;
  --background: #fff;
  --card-bg: #f9f9f9;
  --upload-bg-light: #e0e0e0;
  --upload-bg-dark: #2a2a2a;
  -webkit-overflow-scrolling: touch; /* Improves scrolling on iOS */
  scrollbar-width: none; /* Hide scrollbar for Firefox */
  -ms-overflow-style: none; /* Hide scrollbar for IE and older Edge */
}

body.dark {
  --text: #f0f0f0;
  --accent: #00d4ff;
  --background: #121212;
  --card-bg: #1e1e1e;
}

body {
  background-color: var(--background);
  color: var(--text);
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  margin: 0;
  padding: 0;
  transition: background-color 0.3s, color 0.3s;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1em 2em;
  background-color: var(--card-bg);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

header h1 {
  margin: 0;
  font-size: 1.5em;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 1em;
  margin: 0;
  padding: 0;
}

nav a {
  text-decoration: none;
  color: var(--text);
  font-weight: bold;
}

#info-section {
  margin: 0 auto;
  width: 60vw;
  align-self: center;
  -webkit-overflow-scrolling: touch; /* Improves scrolling on iOS */
  scrollbar-width: none; /* Hide scrollbar for Firefox */
  -ms-overflow-style: none; /* Hide scrollbar for IE and older Edge */
}

#info-section::webkit-scrollbar {
  display: none;
}


#themeToggle {
  font-size: 1.2em;
  cursor: pointer;
  background: none;
  border: none;
  color: var(--accent);
}

#hero {
  padding: 2em;
  text-align: center;
  background: linear-gradient(to right, #eef2f3, #ffffff);
  color: var(--text);
  transition: background 0.3s, color 0.3s;
  width: 60vw;
  margin: 0 auto;
  border-radius: 10px;
}

#hero h2 {
  font-size: 2em;
  margin-bottom: 0.5em;
}

#hero p {
  font-size: 1.1em;
  color: #555;
}

body.dark #hero {
  background: linear-gradient(to right, #2a2a2a, #1e1e1e);
  color: #f0f0f0;
}

/* Container grid */
.container-grid {
  display: flex;
  gap: 2em;
  flex-wrap: nowrap;
  padding: 2em;
  justify-content: center;
  width: 60vw;
  margin: 0 auto;
}

/* Left and right panel */
.container-card {
  background-color: var(--card-bg);
  border-radius: 10px;
  padding: 1.5em;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.05);
  flex: 1 1 450px;
  display: flex;
  flex-direction: column;
  max-height: 75vh;
  overflow-y: auto;
  overflow-x: hidden;
}

.container-card::webkit-scrollbar {
  display: none;
}
/* Upload area */
.upload-area {
  border: 2px dashed #ccc;
  border-radius: 10px;
  padding: 2em;
  text-align: center;
  cursor: pointer;
  transition: background-color 0.3s;
  background-color: var(--upload-bg-light);
  color: var(--text);
  user-select: none;
}

body.dark .upload-area {
  background-color: var(--upload-bg-dark);
}

.upload-area:hover {
  background-color: #d0d0d0;
}

body.dark .upload-area:hover {
  background-color: #3a3a3a;
}

.upload-area.dragover {
  background-color: #d0d0d0 !important;
  border-color: var(--accent) !important;
}

.upload-area span {
  color: var(--accent);
  text-decoration: underline;
  cursor: pointer;
}

/* Loading bar */
.loading-bar {
  width: 100%;
  height: 10px;
  background: #ddd;
  border-radius: 5px;
  margin: 1em 0;
  overflow: hidden;
}

.loading-bar .progress {
  width: 0;
  height: 100%;
  background: var(--accent);
  transition: none;
}

.hidden {
  display: none !important;
}

.error-message {
  color: red;
  margin: 0.5em 0;
  font-size: 0.9em;
}

/* Convert controls */
.convert-controls {
  display: flex;
  align-items: center;
  gap: 1em;
  margin-top: 1em;
}

#convert-btn {
  padding: 0.75em 1.5em;
  background-color: var(--accent);
  border: none;
  color: white;
  font-size: 1em;
  border-radius: 5px;
  cursor: pointer;
  transition: background-color 0.3s;
}

#convert-btn:hover {
  background-color: #005fa3;
}

#format-select {
  padding: 0.5em 1em;
  font-size: 1em;
  border-radius: 5px;
  border: 1px solid #ccc;
  cursor: pointer;
  background-color: var(--card-bg);
  color: var(--text);
  transition: background-color 0.3s, color 0.3s, border-color 0.3s;
}

body.dark #format-select {
  background-color: var(--card-bg);
  color: var(--text);
  border: 1px solid #555;
}

/* Preview container grid */
.preview-container {
  margin-top: 1em;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 10px;
  overflow: visible;
  perspective: 1000px;
}


.preview-container::webkit-scrollbar {
  display: none;
}

/* Image tile styling */
.preview-container img,
.tile-img {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  border-radius: 8px;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  cursor: pointer;
  user-select: none;
  position: relative;
  z-index: 1;
}

/* Hover grow with 1s delay */
.preview-container img:hover,
.preview-container a img:hover {
  transform: scale(1.05) translateZ(20px);
  z-index: 20;
  box-shadow: 0 15px 30px rgba(0,0,0,0.4);
  position: relative;
}

/* Converted preview anchors styling */
.preview-container a {
  display: block;
  text-align: center;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.9em;
}

/* Slide out animation for images leaving original preview */
.slide-out {
  animation: slideOut 0.5s forwards ease;
}

@keyframes slideOut {
  0% { transform: translateX(0); opacity: 1; }
  100% { transform: translateX(200%); opacity: 0; }
}

/* Scrollbar style for preview containers */
.preview-container::-webkit-scrollbar {
  width: 8px;
}
.preview-container::-webkit-scrollbar-thumb {
  background-color: var(--accent);
  border-radius: 4px;
}

/* Scroll for panels */
.left-panel, .right-panel {
  scrollbar-width: thin;
  scrollbar-color: var(--accent) transparent;
}

body.dark #convert-btn {
  background-color: var(--accent);
  color: #121212;
}

footer {
  text-align: center;
  padding: 2em;
  background-color: var(--card-bg);
  margin-top: 2em;
  color: var(--text);
}

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

html, body {
  height: 100%;
  margin: 0;
}

.body-wrapper {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}