/* =============================================================================
   Retirement Research Digest — Stylesheet
   ============================================================================= */

/* --- CSS Variables (consistent with ssmbar) --- */
:root {
  --brand-navy:       #0f1741;
  --brand-blue:       #003477;
  --brand-orange:     #F36107;

  --bg-page:         #FAFBFC;
  --bg-card:         #FFFFFF;
  --bg-card-alt:     #F3F4F6;
  --shadow-card:     0 1px 3px rgba(0, 0, 0, 0.08);

  --text-primary:    #1a1a2e;
  --text-secondary:  #6b7280;
  --text-muted:      #737980;

  --accent-blue:     #2563EB;
  --accent-orange:   #F36107;
  --border:          #E5E7EB;
  --border-focus:    #2563EB;

  --color-positive:  #059669;

  --bg-dark:         #0f1741;
  --text-on-dark:    #e8e8e8;
  --text-muted-dark: #a0a0b0;

  --font-family:     'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

/* --- Base --- */
* { box-sizing: border-box; }

body {
  background-color: var(--bg-page);
  color: var(--text-primary);
  font-family: var(--font-family);
  font-size: 0.9rem;
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a { color: var(--accent-blue); text-decoration: none; }
a:hover { color: var(--brand-blue); text-decoration: underline; }

/* --- Navbar --- */
.navbar {
  background-color: var(--bg-dark) !important;
  border-bottom: 2px solid var(--brand-blue);
  padding: 0.5rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar-brand {
  color: #fff !important;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

.navbar-attr {
  font-size: 0.72rem;
  color: var(--text-muted-dark);
}

/* --- Filter Bar --- */
.filter-bar {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  padding: 0.75rem 1rem;
  position: sticky;
  top: 0;
  z-index: 100;
}

.filter-row {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.search-wrapper {
  flex: 0 0 280px;
  position: relative;
}

.search-wrapper::before {
  content: '';
  position: absolute;
  left: 0.65rem;
  top: 50%;
  transform: translateY(-50%);
  width: 14px;
  height: 14px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20' fill='%23737980'%3E%3Cpath fill-rule='evenodd' d='M8 4a4 4 0 100 8 4 4 0 000-8zM2 8a6 6 0 1110.89 3.476l4.817 4.817a1 1 0 01-1.414 1.414l-4.816-4.816A6 6 0 012 8z'/%3E%3C/svg%3E");
  background-size: contain;
  background-repeat: no-repeat;
  pointer-events: none;
}

.search-input {
  width: 100%;
  padding: 0.4rem 0.75rem 0.4rem 2rem;
  border: 1.5px solid var(--border);
  border-radius: 0.375rem;
  font-size: 0.85rem;
  font-family: var(--font-family);
  color: var(--text-primary);
  background: var(--bg-page);
  transition: border-color 0.15s;
}

.search-input:focus {
  outline: 2px solid var(--border-focus);
  outline-offset: 1px;
  border-color: var(--border-focus);
}

.search-input::placeholder {
  color: var(--text-muted);
}

.topic-pills {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
  flex: 1;
}

.topic-pill {
  background: var(--bg-card);
  border: 1.5px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 0.3rem 0.75rem;
  border-radius: 2rem;
  cursor: pointer;
  transition: all 0.15s;
  white-space: nowrap;
  user-select: none;
}

.topic-pill:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 1px;
}

.topic-pill:hover {
  border-color: var(--accent-blue);
  color: var(--text-primary);
}

.topic-pill.active {
  background: var(--accent-blue);
  border-color: var(--accent-blue);
  color: #fff;
}

.time-filter {
  flex-shrink: 0;
}

.time-select {
  padding: 0.4rem 0.75rem;
  border: 1.5px solid var(--border);
  border-radius: 0.375rem;
  font-size: 0.85rem;
  font-family: var(--font-family);
  color: var(--text-primary);
  background: var(--bg-page);
  cursor: pointer;
}

.time-select:focus {
  outline: 2px solid var(--border-focus);
  outline-offset: 1px;
  border-color: var(--border-focus);
}

/* --- Status Bar --- */
.status-bar {
  padding: 0.5rem 1rem;
  font-size: 0.8rem;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border);
  background: var(--bg-page);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.clear-filters-btn {
  background: none;
  border: none;
  color: var(--accent-blue);
  font-size: 0.78rem;
  font-weight: 500;
  cursor: pointer;
  padding: 0;
  margin-left: auto;
}

.clear-filters-btn:hover {
  text-decoration: underline;
}

.clear-filters-btn:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 1px;
}

/* --- Paper List --- */
.paper-list {
  max-width: 900px;
  margin: 0 auto;
  padding: 1rem 1rem 0;
}

/* --- Paper Card --- */
.paper-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  padding: 1rem 1.25rem;
  margin-bottom: 0.75rem;
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.15s, border-color 0.15s;
}

.paper-card:hover {
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.12);
  border-color: #d1d5db;
}

.paper-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 0.35rem;
}

.paper-title {
  font-size: 0.95rem;
  font-weight: 600;
  line-height: 1.35;
  color: var(--text-primary);
}

.paper-title a {
  color: var(--text-primary);
  text-decoration: none;
}

.paper-title a:hover {
  color: var(--accent-blue);
  text-decoration: underline;
}

.paper-date {
  font-size: 0.78rem;
  color: var(--text-muted);
  white-space: nowrap;
  flex-shrink: 0;
}

.paper-meta {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
  line-height: 1.4;
}

.paper-authors {
  display: inline;
}

.paper-source {
  color: var(--text-muted);
}

.badge-new {
  display: inline-block;
  background: var(--accent-orange);
  color: #fff;
  font-size: 0.65rem;
  font-weight: 700;
  padding: 1px 6px;
  border-radius: 3px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-left: 0.4rem;
  vertical-align: text-top;
  position: relative;
  top: -1px;
}

.paper-topics {
  display: flex;
  gap: 0.35rem;
  flex-wrap: wrap;
  margin-bottom: 0.5rem;
}

.paper-topic-tag {
  font-size: 0.7rem;
  font-weight: 500;
  padding: 2px 8px;
  border-radius: 3px;
  background: var(--bg-card-alt);
  color: var(--text-muted);
  border: none;
}

.paper-abstract {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.55;
  overflow: hidden;
}

.paper-abstract.collapsed {
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
}

.paper-abstract-toggle {
  font-size: 0.75rem;
  color: var(--accent-blue);
  cursor: pointer;
  margin-top: 0.25rem;
  font-weight: 500;
  display: inline-block;
  background: none;
  border: none;
  padding: 0;
  font-family: var(--font-family);
}

.paper-abstract-toggle:hover {
  text-decoration: underline;
}

.paper-abstract-toggle:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 1px;
}

/* --- Load More --- */
.load-more {
  text-align: center;
  padding: 1rem 0 2rem;
  max-width: 900px;
  margin: 0 auto;
}

.load-more-btn {
  background: var(--bg-card);
  border: 1.5px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 0.5rem 2rem;
  border-radius: 0.375rem;
  cursor: pointer;
  transition: all 0.15s;
}

.load-more-btn:hover {
  border-color: var(--accent-blue);
  color: var(--accent-blue);
}

.load-more-btn:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 1px;
}

/* --- No Papers --- */
.no-papers {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  max-width: 900px;
  margin: 0 auto;
}

/* --- Footer --- */
.site-footer {
  margin-top: auto;
  padding: 1.5rem 1rem;
  text-align: center;
  font-size: 0.78rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
}

.site-footer a {
  color: var(--text-secondary);
}

/* =============================================================================
   Responsive
   ============================================================================= */

@media (max-width: 767px) {
  .filter-row {
    flex-direction: column;
    align-items: stretch;
    gap: 0.5rem;
  }

  .search-wrapper {
    flex: 1 1 100%;
  }

  .topic-pills {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    flex-wrap: nowrap;
    padding-bottom: 0.25rem;
    mask-image: linear-gradient(to right, black 85%, transparent 100%);
    -webkit-mask-image: linear-gradient(to right, black 85%, transparent 100%);
  }

  .topic-pill {
    flex-shrink: 0;
  }

  .time-filter {
    align-self: flex-start;
  }

  .filter-bar {
    position: static;
  }

  .paper-header {
    flex-direction: column;
    gap: 0.25rem;
  }

  .paper-card {
    padding: 0.75rem 1rem;
  }

  .paper-list {
    padding: 0.75rem 0.5rem 0;
  }
}