:root {
  --background: #232946;
  --headline: #fffffe;
  --paragraph: #b8c1ec;
  --accent: #4FC3F7;
  --accent-hover: #29B6F6;
  --stroke: #121629;

  /* Logical Mapping for Components */
  --primary: var(--accent);
  --primary-hover: var(--accent-hover);
  --primary-text: var(--background);
  --card-bg: #1b2038;
  --border-color: var(--stroke);

  --radius: 24px;
  --radius-btn: 14px;
  --transition: all 0.3s ease;
  --shadow-soft: 0 10px 30px rgba(0, 0, 0, 0.15);
  --shadow-hover: 0 15px 35px rgba(0, 0, 0, 0.25);
}

body {
  font-family: 'Outfit', sans-serif;
  background-color: var(--background);
  color: var(--paragraph);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6,
.card-title {
  font-weight: 700;
  color: var(--headline);
  letter-spacing: -0.5px;
}

h1,
.display-4 {
  color: var(--headline) !important;
}

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

a:hover, .hover-accent:hover {
  color: var(--accent) !important;
}

/* Bootstrap Overrides */
.text-primary {
  color: var(--accent) !important;
}

.text-dark {
  color: var(--headline) !important;
}

.text-muted {
  color: var(--paragraph) !important;
  opacity: 0.7;
}

.bg-primary {
  background-color: var(--accent) !important;
}

.bg-light,
.bg-white {
  background-color: var(--card-bg) !important;
}

.border {
  border-color: var(--stroke) !important;
}

/* Navbar */
.navbar {
  background: rgba(35, 41, 70, 0.75) !important;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  padding: 1rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  transition: all 0.3s ease;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

.navbar-brand {
  font-weight: 700;
  font-size: 1.5rem;
  color: var(--headline) !important;
}

.navbar-brand i {
  color: var(--accent);
}

.nav-link {
  font-weight: 500;
  color: var(--paragraph) !important;
  padding: 0.5rem 1rem !important;
  border-radius: 12px;
  transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
  color: var(--headline) !important;
  background: rgba(255, 255, 255, 0.05);
}

.navbar-toggler {
  color: var(--headline) !important;
  transition: var(--transition);
}

.navbar-toggler:hover {
  color: var(--accent) !important;
}

/* Buttons */
.btn-primary {
  background: var(--accent);
  color: var(--background);
  border-radius: var(--radius-btn);
  padding: 12px 24px;
  border: none;
  font-weight: 600;
  transition: var(--transition);
}

.btn-primary:hover,
.btn-primary:focus,
.btn-primary:active,
.btn-primary.active {
  background: var(--accent-hover) !important;
  color: var(--background) !important;
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(79, 195, 247, 0.3) !important;
}

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

.btn-outline-primary {
  color: var(--accent);
  border: 1px solid var(--accent);
  background: transparent;
  border-radius: var(--radius-btn);
  padding: 10px 24px;
  font-weight: 600;
}

.btn-outline-primary:hover,
.btn-outline-primary:focus,
.btn-outline-primary:active {
  background: var(--accent) !important;
  color: var(--background) !important;
  transform: translateY(-2px);
  border-color: var(--accent) !important;
}

.btn:focus,
.btn:active:focus {
  outline: none !important;
  box-shadow: 0 0 0 4px rgba(79, 195, 247, 0.15) !important;
}

.btn-outline-secondary {
  color: var(--paragraph);
  border: 1px solid var(--stroke);
  border-radius: var(--radius-btn);
}

.btn-outline-secondary:hover {
  background: var(--stroke);
  color: var(--headline);
}

.btn-outline-danger {
  border-radius: var(--radius-btn);
  border: 1px solid #ef4444;
  color: #ef4444;
}

.btn-outline-danger:hover {
  background: #ef4444;
  color: white;
}

/* Cards */
.card,
.blog-card,
.card-custom {
  background: rgba(27, 32, 56, 0.6) !important;
  backdrop-filter: blur(15px);
  -webkit-backdrop-filter: blur(15px);
  border: 1px solid rgba(255, 255, 255, 0.08) !important;
  border-radius: var(--radius);
  box-shadow: var(--shadow-soft);
  transition: var(--transition);
  overflow: hidden;
  color: var(--paragraph);
}

.card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-5px);
}

.card-img-top {
  aspect-ratio: 2 / 1;
  width: 100%;
  object-fit: cover;
  object-position: center; /* Best default for all types of content */
  transition: var(--transition);
  image-rendering: -webkit-optimize-contrast;
  image-rendering: auto;
  backface-visibility: hidden;
  transform: translateZ(0);
  filter: contrast(1.1) brightness(1.05) saturate(1.1); /* HD Look */
}

.card:hover .card-img-top {
  transform: scale(1.05) translateZ(0);
}

.rounded-circle-img {
  width: 40px;
  height: 40px;
  object-fit: cover;
  border-radius: 50%;
  border: 2px solid var(--stroke);
}

.card-body {
  padding: 1.5rem;
}

/* Glassmorphism Classes */
.glass {
  background: rgba(255, 255, 255, 0.03);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--stroke);
}

/* Forms */
.form-control,
.form-select {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--stroke);
  border-radius: 14px;
  color: var(--headline);
  padding: 0.8rem 1.2rem;
  transition: var(--transition);
}

.form-control:focus {
  background: rgba(255, 255, 255, 0.05);
  border-color: var(--accent);
  color: var(--headline);
  box-shadow: 0 0 0 4px rgba(79, 195, 247, 0.1);
}

.form-control::placeholder {
  color: var(--paragraph);
  opacity: 0.5;
}

.form-text {
  color: var(--paragraph) !important;
  opacity: 0.6;
}

/* Input Group */
.input-group-text {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--stroke);
  color: var(--paragraph);
  border-radius: 14px;
}

.input-group>.form-control,
.input-group>.form-select {
  border-radius: 14px;
}

.input-group>.input-group-text+.form-control {
  border-left: none;
}

.input-group>.form-control:focus+.input-group-text,
.input-group>.form-control:focus {
  border-color: var(--accent);
}

/* Badges */
.badge {
  padding: 0.6em 1.2em;
  border-radius: 10px;
  font-weight: 600;
  color: var(--headline) !important;
}

.bg-primary.bg-opacity-10 {
  background-color: rgba(79, 195, 247, 0.1) !important;
  color: var(--accent) !important;
}

/* Sidebar & Lists */
.list-group-item {
  background: transparent;
  border: none;
  color: var(--paragraph);
  padding: 1rem 1.5rem;
  transition: var(--transition);
}

.list-group-item:hover {
  background: rgba(255, 255, 255, 0.03);
  color: var(--headline);
}

.list-group-item.active {
  background: rgba(79, 195, 247, 0.1) !important;
  color: var(--accent) !important;
  border-left: 4px solid var(--accent) !important;
  border-radius: 0;
}

/* Footer */
footer {
  margin-top: auto;
  padding: 3rem 0;
  background: var(--background);
  border-top: 1px solid var(--stroke);
  color: var(--paragraph);
}

/* Skeleton Loader */
.skeleton {
  background: var(--stroke);
  opacity: 0.5;
  animation: pulse 1.5s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 0.2; }
}

/* Performance: GPU-accelerated transitions */
.card,
.btn,
.nav-link {
  will-change: transform;
}

/* Custom UI Tweaks */
.post-header h1 {
  color: var(--headline);
}

.post-content {
  color: var(--paragraph);
}

.post-content h2,
.post-content h3 {
  color: var(--headline);
}

.profile-header {
  background: linear-gradient(135deg, #1b2038 0%, var(--background) 100%);
  border: 1px solid var(--stroke);
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--background);
}

::-webkit-scrollbar-thumb {
  background: var(--stroke);
  border-radius: 10px;
}

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

/* Animations */
.animate-up {
  transition: var(--transition);
}

.animate-up:hover {
  transform: translateY(-5px);
}

/* SimpleMDE Dark Mode & Sticky Toolbar */
.editor-container .card,
.editor-container .card-body {
  overflow: visible !important; 
}

.editor-toolbar {
  background: #1b2038 !important; 
  border: 1px solid var(--stroke) !important;
  border-bottom: 2px solid var(--accent) !important;
  opacity: 1 !important;
  position: -webkit-sticky !important;
  position: sticky !important;
  top: 71px !important; 
  z-index: 1025 !important;
  border-radius: 12px 12px 0 0 !important;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5) !important;
  margin-top: 0;
}

.CodeMirror {
  background: var(--card-bg) !important;
  color: var(--paragraph) !important;
  border-color: var(--stroke) !important;
  z-index: 1 !important;
  border-radius: 0 0 12px 12px !important;
}

.editor-toolbar a {
  color: var(--paragraph) !important;
}

.editor-toolbar a:hover,
.editor-toolbar a.active {
  background: var(--stroke) !important;
  color: var(--accent) !important;
}

.CodeMirror {
  background: var(--card-bg) !important;
  color: var(--paragraph) !important;
  border-color: var(--stroke) !important;
}

.CodeMirror-cursor {
  border-left: 2px solid var(--headline) !important;
}

input,
textarea,
select {
  caret-color: var(--headline);
}

.editor-statusbar {
  color: var(--paragraph) !important;
}

/* Bootstrap Dropdowns */
.dropdown-menu {
  background-color: var(--card-bg) !important;
  border: 1px solid var(--stroke) !important;
  box-shadow: var(--shadow-hover) !important;
}

.dropdown-item {
  color: var(--paragraph) !important;
}

.dropdown-item:hover {
  background-color: var(--stroke) !important;
  color: var(--headline) !important;
}

.dropdown-divider {
  border-top: 1px solid var(--stroke) !important;
}

/* Author Card & Profile Section */
.author-card,
.profile-card {
  background: var(--card-bg) !important;
  border: 1px solid var(--stroke) !important;
  border-radius: var(--radius);
}

/* Select Styling */
select option {
  background: var(--card-bg);
  color: var(--paragraph);
}

/* Top Loading Bar (NProgress-style) */
.top-loader {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), #81D4FA, var(--accent));
  background-size: 200% 100%;
  animation: shimmer 1.5s linear infinite;
  z-index: 99999;
  transition: width 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 0 8px rgba(79, 195, 247, 0.4);
  pointer-events: none;
}

.top-loader.active {
  animation: shimmer 1.5s linear infinite, loadProgress 2s ease-out forwards;
}

.top-loader.done {
  width: 100% !important;
  opacity: 0;
  transition: width 0.2s ease, opacity 0.4s ease 0.2s;
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

@keyframes loadProgress {
  0% { width: 0%; }
  20% { width: 30%; }
  50% { width: 60%; }
  80% { width: 85%; }
  100% { width: 92%; }
}

/* Content Fade-In */
.content-loading {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.content-loaded {
  opacity: 1 !important;
  transform: translateY(0) !important;
}

/* Legacy overlay (hidden by default, used as fallback) */
.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(18, 22, 41, 0.8);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 9999;
  display: none;
  justify-content: center;
  align-items: center;
  transition: var(--transition);
}

.loading-overlay.active {
  display: flex;
}

/* Searchable Select Custom UI */
.search-select-container {
  position: relative;
  width: 100%;
}

.search-select-menu {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  z-index: 1050;
  background: var(--card-bg);
  border: 1px solid var(--stroke);
  border-radius: var(--radius);
  max-height: 300px;
  overflow-y: auto;
  display: none;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  margin-top: 5px;
}

.search-select-menu.show {
  display: block;
}

.search-select-option {
  padding: 10px 15px;
  cursor: pointer;
  transition: all 0.2s;
  color: var(--paragraph);
}

.search-select-option:hover {
  background: var(--stroke);
  color: var(--accent);
}

.search-select-option.selected {
  background: rgba(79, 195, 247, 0.1);
  color: var(--accent);
  font-weight: 600;
}

.search-select-search-box {
  position: sticky;
  top: 0;
  background: var(--card-bg);
  padding: 10px;
  border-bottom: 1px solid var(--stroke);
  z-index: 2;
}

.search-select-input-field {
  background: rgba(255, 255, 255, 0.05) !important;
  border: 1px solid var(--stroke) !important;
  color: white !important;
  padding: 8px 12px;
  width: 100%;
  border-radius: 5px;
}

.spinner-border {
  color: var(--accent) !important;
}

/* ===== Progressive Image Loading System ===== */

/* Wrapper that holds shimmer placeholder + real image */
.img-progressive {
  position: relative;
  overflow: hidden;
  background: var(--stroke);
}

/* Shimmer placeholder while image loads */
.img-progressive::before {
  content: '';
  position: absolute;
  inset: 0;
  z-index: 2;
  background: linear-gradient(
    110deg,
    var(--stroke) 8%,
    rgba(255, 255, 255, 0.06) 18%,
    var(--stroke) 33%
  );
  background-size: 200% 100%;
  animation: imgShimmer 1.5s linear infinite;
  border-radius: inherit;
  transition: opacity 0.5s ease;
}

/* Hide shimmer once image is loaded */
.img-progressive.loaded::before {
  opacity: 0;
  pointer-events: none;
}

/* Small icon hint in center while loading */
.img-progressive::after {
  content: '\F425'; /* bi-image icon */
  font-family: 'bootstrap-icons';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 1;
  font-size: 1.8rem;
  color: var(--paragraph);
  opacity: 0.15;
  transition: opacity 0.4s ease;
}

.img-progressive.loaded::after {
  opacity: 0;
}

@keyframes imgShimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* Image inside the progressive wrapper */
.img-progressive img,
.img-progressive .progressive-img {
  opacity: 0;
  transform: scale(1.02);
  transition: opacity 0.6s cubic-bezier(0.4, 0, 0.2, 1),
              transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  will-change: opacity, transform;
}

.img-progressive.loaded img,
.img-progressive.loaded .progressive-img {
  opacity: 1;
  transform: scale(1);
}

/* Variant for card thumbnails */
.card .img-progressive {
  border-radius: var(--radius) var(--radius) 0 0;
}

/* Variant for rounded images (avatars, etc.) */
.img-progressive.rounded-circle {
  border-radius: 50%;
}

/* Variant for the post detail hero thumbnail */
.img-progressive.post-thumb-wrapper {
  border-radius: 24px;
  margin-bottom: 3rem;
}

/* Recommendation card images */
.img-progressive.rec-img-wrapper {
  border-radius: 16px 16px 0 0;
}

/* Error state — show fallback icon */
.img-progressive.error::before {
  opacity: 0;
}

.img-progressive.error::after {
  content: '\F622'; /* bi-exclamation-triangle */
  opacity: 0.3;
  font-size: 1.5rem;
  color: #ef4444;
}