/**
 * MD viewer modal — notes, syllabus, papers, prep-shorts.
 * Matches app aesthetics: variables, gradients, shadows, typography.
 */

.md-viewer-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.48);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--app-safe-top) 16px var(--app-safe-bottom);
  animation: md-viewer-fade 0.2s var(--app-ease-out);
}

.md-viewer-overlay[aria-hidden="true"] {
  display: none;
}

@keyframes md-viewer-fade {
  from { opacity: 0; }
  to { opacity: 1; }
}

.md-viewer {
  background: var(--app-surface);
  border-radius: var(--app-radius-lg);
  max-height: 88vh;
  width: 100%;
  max-width: min(var(--app-content-max, 640px), 92vw);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  box-shadow: var(--app-shadow-lg), 0 0 0 1px rgba(99, 102, 241, 0.08);
  border: 1px solid var(--app-border-soft);
  animation: md-viewer-slide 0.25s var(--app-ease-out);
}

@keyframes md-viewer-slide {
  from {
    opacity: 0;
    transform: translateY(12px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.md-viewer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  background: var(--app-gradient-soft);
  border-bottom: 1px solid var(--app-border-soft);
  flex-shrink: 0;
}

.md-viewer-title {
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--app-text);
  letter-spacing: -0.02em;
  flex: 1;
  padding-right: 12px;
  min-width: 0;
}

.md-viewer-close {
  width: 40px;
  height: 40px;
  border: none;
  background: var(--app-surface);
  color: var(--app-text-secondary);
  font-size: 1.5rem;
  line-height: 1;
  cursor: pointer;
  border-radius: var(--app-radius-full);
  -webkit-tap-highlight-color: transparent;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--app-shadow);
  transition: color 0.15s, background 0.15s;
}

.md-viewer-close:hover {
  color: var(--app-text);
  background: var(--app-bg-elevated);
}

.md-viewer-close:active {
  transform: scale(0.96);
}

.md-viewer-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.md-viewer-btn-ask-expert {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  font-size: var(--app-text-sm);
  font-weight: 600;
  color: var(--app-primary);
  background: var(--app-primary-soft);
  border-radius: var(--app-radius-sm);
  text-decoration: none;
  -webkit-tap-highlight-color: transparent;
  transition: background 0.15s, color 0.15s;
}

.md-viewer-btn-ask-expert:hover {
  background: rgba(99, 102, 241, 0.22);
  color: var(--app-primary-hover);
}

.md-viewer-btn-ask-expert img {
  flex-shrink: 0;
  vertical-align: middle;
}

.md-viewer-btn-pdf {
  padding: 8px 14px;
  font-size: var(--app-text-sm);
  font-weight: 600;
  background: var(--app-primary);
  color: #fff;
  border: none;
  border-radius: var(--app-radius-sm);
  cursor: pointer;
  transition: background 0.15s;
}

.md-viewer-btn-pdf:hover {
  background: var(--app-primary-hover);
}

.md-viewer-body {
  padding: 24px 20px 28px;
  overflow-y: auto;
  flex: 1;
  -webkit-overflow-scrolling: touch;
  background: linear-gradient(180deg, var(--app-surface) 0%, var(--app-bg) 100%);
  color: var(--app-text);
  font-family: var(--app-font);
}

/* Predicted papers overlay: subtle book-like paper tint */
#paper-md-overlay .md-viewer {
  background: linear-gradient(90deg, #eae6df 0%, #f5f2eb 8%, #faf8f3 50%, #f5f2eb 92%, #eae6df 100%);
  box-shadow: -6px 0 20px rgba(0,0,0,0.06), 4px 4px 24px rgba(0,0,0,0.08);
}
#paper-md-overlay .md-viewer-body {
  background: transparent;
}

/* Reading width for long content */
.md-viewer-body > p,
.md-viewer-body > .md-h1,
.md-viewer-body > .md-h2,
.md-viewer-body > .md-h3,
.md-viewer-body > .md-li {
  max-width: 56ch;
}

/* Typography — notes & syllabus content */
.md-viewer-body .md-h1 {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--app-text);
  margin: 0 0 8px;
  letter-spacing: -0.025em;
  line-height: 1.28;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--app-border-soft);
}

.md-viewer-body .md-h2 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--app-text);
  margin: 1.5em 0 0.6em;
  padding: 10px 14px 10px 12px;
  padding-left: 12px;
  border-left: 4px solid var(--app-primary);
  background: var(--app-primary-soft);
  border-radius: 0 var(--app-radius-sm) var(--app-radius-sm) 0;
  letter-spacing: -0.01em;
  line-height: 1.35;
}

.md-viewer-body .md-h2:first-child {
  margin-top: 0;
}

.md-viewer-body .md-h3 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--app-text);
  margin: 1.1em 0 0.4em;
  letter-spacing: -0.01em;
}

.md-viewer-body p {
  margin: 0 0 14px;
  line-height: 1.65;
  font-size: 0.9375rem;
  color: var(--app-text-secondary);
}

.md-viewer-body p:last-child {
  margin-bottom: 0;
}

/* Label-style: paragraph starting with bold (e.g. "One line:", "Example:", "Teacher tip:") */
.md-viewer-body p:has(strong:first-child) {
  color: var(--app-text);
  margin-bottom: 6px;
}

.md-viewer-body p strong:first-child {
  font-size: 0.8125rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--app-primary);
  display: inline-block;
  margin-bottom: 2px;
}

.md-viewer-body strong {
  font-weight: 700;
  color: var(--app-text);
}

.md-viewer-body em {
  color: var(--app-text-secondary);
  font-style: italic;
}

/* List styling — notes & syllabus bullet lists */
.md-viewer-body .md-li {
  margin: 8px 0;
  padding: 6px 0 6px 1.35em;
  list-style: none;
  font-size: 0.9375rem;
  color: var(--app-text-secondary);
  line-height: 1.55;
  position: relative;
}

.md-viewer-body .md-li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--app-primary);
  opacity: 0.7;
}

/* Tighten spacing when list follows a label paragraph */
.md-viewer-body p + .md-li {
  margin-top: 2px;
}

/* Horizontal rule if present in content */
.md-viewer-body hr {
  border: none;
  height: 1px;
  background: var(--app-border-soft);
  margin: 1.25em 0;
}

/* Links inside content */
.md-viewer-body a {
  color: var(--app-primary);
  text-decoration: none;
  font-weight: 600;
}

.md-viewer-body a:hover {
  text-decoration: underline;
}

/* Print: hide overlay chrome */
@media print {
  .md-viewer-overlay {
    position: static;
    background: none;
    backdrop-filter: none;
    padding: 0;
  }
  .md-viewer {
    max-height: none;
    box-shadow: none;
    border: none;
  }
  .md-viewer-close,
  .md-viewer-btn-pdf,
  .md-viewer-btn-ask-expert {
    display: none !important;
  }
  .md-viewer-header {
    border-bottom: 1px solid var(--app-border);
  }
}