:root {
  --app-bg: linear-gradient(180deg, #f6f8fc 0%, #eef3f9 100%);
  --app-surface: rgba(255, 255, 255, 0.9);
  --app-surface-border: rgba(15, 23, 42, 0.08);
  --app-navbar: rgba(255, 255, 255, 0.78);
  --app-shadow: 0 10px 28px rgba(15, 23, 42, 0.08);
  --app-muted: #5f6b7a;
  --app-accent: #2563eb;
  --app-accent-soft: rgba(37, 99, 235, 0.12);
  --app-accent-warm: #f59e0b;
  --app-title: #0f172a;
}

[data-bs-theme="dark"] {
  --app-bg: radial-gradient(circle at top, #192234 0%, #0f172a 45%, #0b1120 100%);
  --app-surface: rgba(17, 24, 39, 0.9);
  --app-surface-border: rgba(148, 163, 184, 0.18);
  --app-navbar: rgba(15, 23, 42, 0.72);
  --app-shadow: 0 14px 36px rgba(2, 6, 23, 0.38);
  --app-muted: #9aa8bc;
  --app-accent: #60a5fa;
  --app-accent-soft: rgba(96, 165, 250, 0.18);
  --app-accent-warm: #fbbf24;
  --app-title: #f8fafc;
}

body {
  background: var(--app-bg);
  min-height: 100vh;
  position: relative;
}

body::before,
body::after {
  content: "";
  position: fixed;
  inset: auto;
  border-radius: 999px;
  pointer-events: none;
  z-index: 0;
  filter: blur(70px);
  opacity: 0.55;
}

body::before {
  width: 280px;
  height: 280px;
  top: 110px;
  right: 7vw;
  background: color-mix(in srgb, var(--app-accent) 60%, transparent);
}

body::after {
  width: 220px;
  height: 220px;
  left: 4vw;
  bottom: 8vh;
  background: color-mix(in srgb, var(--app-accent-warm) 50%, transparent);
}

.portfolio-strip {
  position: relative;
  z-index: 2;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 0.45rem;
  min-height: 1.6rem;
  padding: 0.22rem 0.75rem;
  background: color-mix(in srgb, var(--app-navbar) 86%, transparent);
  border-bottom: 1px solid var(--app-surface-border);
  color: var(--app-muted);
  font-size: 0.78rem;
  font-weight: 600;
}

.portfolio-strip a {
  color: var(--app-accent);
  text-decoration: none;
}

.portfolio-strip a:hover {
  text-decoration: underline;
}

.app-navbar {
  background: var(--app-navbar);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--app-surface-border);
}

.app-navbar .container {
  align-items: center;
}

.navbar-brand {
  position: relative;
  display: inline-flex;
  align-items: center;
  letter-spacing: -0.03em;
  color: var(--app-title) !important;
  padding-bottom: 0.28rem;
  margin-bottom: 0;
}

.navbar-brand::after {
  content: "";
  position: absolute;
  left: 0;
  right: 18%;
  bottom: -0.18rem;
  height: 0.28rem;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--app-accent), var(--app-accent-warm));
  opacity: 0.9;
}

.app-navbar .ms-auto {
  align-items: center;
}

.language-form {
  margin: 0;
}

.language-select {
  min-width: 8.5rem;
}

.app-card,
.card,
.list-group-item {
  border-color: var(--app-surface-border) !important;
}

.card,
.list-group,
.list-group-item {
  background: var(--app-surface);
  box-shadow: var(--app-shadow);
}

.card {
  border-radius: 1.15rem;
  overflow: hidden;
}

.card::before {
  content: "";
  display: block;
  height: 3px;
  background: linear-gradient(90deg, var(--app-accent), transparent 70%);
  opacity: 0.9;
}

.list-group-item + .list-group-item {
  border-top-color: var(--app-surface-border);
}

h1, h2, h3, .h1, .h2, .h3 {
  color: var(--app-title);
  letter-spacing: -0.04em;
}

.text-muted,
.small.text-muted,
.form-text {
  color: var(--app-muted) !important;
}

.form-control,
.form-select,
textarea.form-control {
  box-shadow: none;
  border-radius: 0.9rem;
}

.form-control:focus,
.form-select:focus {
  box-shadow: 0 0 0 0.2rem rgba(59, 130, 246, 0.18);
}

.btn {
  border-radius: 0.85rem;
}

.btn-primary {
  background: linear-gradient(135deg, var(--app-accent), color-mix(in srgb, var(--app-accent) 72%, white));
  border-color: transparent;
  box-shadow: 0 8px 18px color-mix(in srgb, var(--app-accent) 20%, transparent);
}

.btn-primary:hover,
.btn-primary:focus {
  background: linear-gradient(135deg, color-mix(in srgb, var(--app-accent) 92%, black), var(--app-accent));
  border-color: transparent;
}

.copy-prompt-cta {
  animation: promptCtaPulse 2.4s ease-in-out infinite;
  position: relative;
}

body.prompt-copied .copy-prompt-cta {
  animation: none;
}

.copy-prompt-cta:hover,
.copy-prompt-cta:focus-visible {
  animation-play-state: paused;
  transform: translateY(-1px);
}

.ai-tool-cta {
  position: relative;
}

body.prompt-copied .ai-tool-cta {
  animation: promptCtaPulse 2.4s ease-in-out infinite;
}

body.prompt-copied .ai-tool-cta:hover,
body.prompt-copied .ai-tool-cta:focus-visible {
  animation-play-state: paused;
  transform: translateY(-1px);
}

@keyframes promptCtaPulse {
  0%,
  100% {
    box-shadow:
      0 8px 18px color-mix(in srgb, var(--app-accent) 18%, transparent),
      0 0 0 0 color-mix(in srgb, var(--app-accent) 38%, transparent);
    filter: brightness(1);
  }

  50% {
    box-shadow:
      0 12px 26px color-mix(in srgb, var(--app-accent) 34%, transparent),
      0 0 0 0.45rem color-mix(in srgb, var(--app-accent) 0%, transparent);
    filter: brightness(1.09);
  }
}

@media (prefers-reduced-motion: reduce) {
  .copy-prompt-cta,
  body.prompt-copied .ai-tool-cta {
    animation: none;
  }
}

.btn-outline-secondary,
.btn-outline-dark,
.btn-outline-danger {
  background: color-mix(in srgb, var(--app-surface) 92%, transparent);
}

.alert {
  border-radius: 1rem;
  border-color: transparent;
}

.badge {
  border-radius: 999px;
  padding-inline: 0.72rem;
}

main.container {
  position: relative;
  z-index: 1;
}

details > summary {
  list-style: none;
}

details > summary::-webkit-details-marker {
  display: none;
}

details > summary::before {
  content: "▸";
  display: inline-block;
  margin-right: 0.55rem;
  transition: transform 0.2s ease;
}

details[open] > summary::before {
  transform: rotate(90deg);
}

.prompt-summary {
  cursor: pointer;
}

.quiz-stat-min {
  min-width: 88px;
}

.editor-shell {
  position: relative;
}

.editor-shell::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 6px;
  border-radius: 999px;
  background: linear-gradient(180deg, var(--app-accent), var(--app-accent-warm));
  opacity: 0.9;
}

.editor-shell .card-body {
  padding-left: 1.5rem;
}

.question-card {
  border: 1px solid color-mix(in srgb, var(--app-accent) 22%, var(--app-surface-border)) !important;
  box-shadow: 0 12px 28px color-mix(in srgb, var(--app-accent) 10%, transparent);
}

.question-card::before {
  background: linear-gradient(90deg, var(--app-accent), var(--app-accent-warm) 85%);
}

.question-card .card-body {
  background:
    linear-gradient(180deg, color-mix(in srgb, var(--app-accent-soft) 42%, transparent), transparent 28%),
    var(--app-surface);
}

.question-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.question-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 2.15rem;
  height: 2.15rem;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 700;
  color: white;
  background: linear-gradient(135deg, var(--app-accent), color-mix(in srgb, var(--app-accent-warm) 38%, var(--app-accent)));
  box-shadow: 0 8px 18px color-mix(in srgb, var(--app-accent) 24%, transparent);
}

.question-subtitle {
  font-size: 0.82rem;
  color: var(--app-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.editor-section {
  border: 1px solid var(--app-surface-border);
  border-radius: 1rem;
  background: color-mix(in srgb, var(--app-surface) 86%, transparent);
  padding: 1rem;
}

.editor-section-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.75rem;
}

.editor-section-title span {
  font-weight: 700;
  letter-spacing: -0.02em;
}

.answer-item,
.source-item {
  border: 1px solid color-mix(in srgb, var(--app-surface-border) 88%, transparent);
  border-radius: 0.9rem;
  background: color-mix(in srgb, var(--app-surface) 94%, transparent);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.answer-item:focus-within,
.source-item:focus-within,
.editor-section:focus-within {
  border-color: color-mix(in srgb, var(--app-accent) 46%, var(--app-surface-border));
}

.answer-item:focus-within,
.source-item:focus-within {
  transform: translateY(-1px);
}

.question-card textarea,
.question-card input[type="text"] {
  background: color-mix(in srgb, var(--app-surface) 96%, transparent);
}

.question-feedback {
  border-top: 1px solid var(--app-surface-border);
}

.question-explanation {
  border: 1px solid var(--app-surface-border);
  border-radius: 0.9rem;
  background: color-mix(in srgb, var(--app-accent-soft) 40%, transparent);
  padding: 0.75rem 0.9rem;
}

.revealed-correct {
  color: color-mix(in srgb, var(--bs-success) 26%, currentColor);
}

[data-bs-theme="dark"] .revealed-correct {
  color: color-mix(in srgb, var(--bs-success) 42%, currentColor);
}

@media (max-width: 768px) {
  body::before,
  body::after {
    opacity: 0.32;
  }

  .navbar .container {
    gap: 0.75rem;
  }

  .navbar .ms-auto {
    width: 100%;
    justify-content: flex-end;
    flex-wrap: wrap;
  }
}