/* ==========================================================================
   PeptiLine Design System
   Shared visual language: tokens, typography, navigation, footer, and the
   reusable content components (hero, section header, stat block, screenshot
   frame, tool card, workflow step). Scoped with a `pl-` prefix so it can be
   adopted page by page without touching existing Bootstrap-based UI.
   ========================================================================== */

:root {
  --pl-color-bg: #FFFFFF;
  --pl-color-bg-secondary: #F8FAFC;
  --pl-color-border: #E2E8F0;
  --pl-color-text: #1E293B;
  --pl-color-muted: #64748B;
  --pl-color-primary: #0F4C81;
  --pl-color-accent: #2563EB;
  --pl-color-success: #0F766E;

  --pl-font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;

  --pl-text-hero: 52px;
  --pl-text-section: 32px;
  --pl-text-card: 22px;
  --pl-text-body: 16px;
  --pl-text-caption: 14px;

  --pl-space-1: 8px;
  --pl-space-2: 16px;
  --pl-space-3: 24px;
  --pl-space-4: 32px;
  --pl-space-5: 48px;
  --pl-space-6: 64px;
  --pl-space-7: 96px;

  --pl-max-width: 1200px;
  --pl-radius-sm: 6px;
  --pl-radius: 10px;
}

body {
  font-family: var(--pl-font-sans);
  color: var(--pl-color-text);
  background: var(--pl-color-bg);
}

/* --------------------------------------------------------------------
   Navigation
   -------------------------------------------------------------------- */

.pl-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 9999;
  height: 60px;
  background: var(--pl-color-bg);
  border-bottom: 1px solid var(--pl-color-border);
  display: flex;
  align-items: center;
}

.pl-nav-inner {
  width: 100%;
  max-width: var(--pl-max-width);
  margin: 0 auto;
  padding: 0 var(--pl-space-3);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.pl-nav-brand {
  font-family: var(--pl-font-sans);
  font-size: 20px;
  font-weight: 700;
  color: var(--pl-color-primary);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.pl-nav-brand:hover {
  color: var(--pl-color-primary);
  text-decoration: none;
}

.pl-nav-brand .pl-brand-accent {
  color: var(--pl-color-accent);
}

.pl-nav-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  align-items: center;
  height: 100%;
}

.pl-nav-links li {
  margin: 0;
  padding: 0;
  height: 100%;
  display: flex;
  align-items: center;
}

.pl-nav-links li a {
  display: flex;
  align-items: center;
  height: 100%;
  padding: 0 var(--pl-space-2);
  color: var(--pl-color-text);
  font-size: 15px;
  font-weight: 500;
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color .15s ease, border-color .15s ease;
}

.pl-nav-links li a:hover,
.pl-nav-links li a:focus {
  color: var(--pl-color-primary);
  border-bottom-color: var(--pl-color-accent);
  text-decoration: none;
  background: none;
}

.pl-nav-links .dropdown-menu {
  display: none;
  background-color: var(--pl-color-bg);
  border: 1px solid var(--pl-color-border);
  border-radius: var(--pl-radius-sm);
  box-shadow: 0 8px 24px rgba(15, 23, 42, 0.08);
  padding: var(--pl-space-1) 0;
  margin-top: 0;
}

.pl-nav-links .dropdown:hover .dropdown-menu {
  display: block;
}

.pl-nav-links .dropdown-menu li {
  height: auto;
}

.pl-nav-links .dropdown-menu li a {
  height: auto;
  padding: 8px 18px;
  color: var(--pl-color-text);
  font-weight: 400;
  border-bottom: none;
}

.pl-nav-links .dropdown-menu li a:hover {
  background-color: var(--pl-color-bg-secondary);
  color: var(--pl-color-primary);
  border-bottom: none;
}

/* --------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------- */

.pl-footer {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--pl-color-bg-secondary);
  border-top: 1px solid var(--pl-color-border);
  padding: 10px 0;
  text-align: center;
}

.pl-footer .pl-footer-content {
  max-width: var(--pl-max-width);
  margin: 0 auto;
  padding: 0 var(--pl-space-3);
  color: var(--pl-color-muted);
  font-size: var(--pl-text-caption);
}

.pl-footer .pl-footer-content a {
  color: var(--pl-color-primary);
  font-weight: 600;
}

/* --------------------------------------------------------------------
   Layout primitives
   -------------------------------------------------------------------- */

.pl-page {
  max-width: var(--pl-max-width);
  margin: 0 auto;
  padding: var(--pl-space-6) var(--pl-space-3) var(--pl-space-7);
}

.pl-section {
  margin-bottom: var(--pl-space-7);
}

.pl-section-header {
  margin-bottom: var(--pl-space-4);
  max-width: 720px;
}

.pl-eyebrow {
  font-size: var(--pl-text-caption);
  font-weight: 600;
  color: var(--pl-color-accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin: 0 0 var(--pl-space-1);
}

.pl-section-header h2 {
  font-size: var(--pl-text-section);
  font-weight: 700;
  color: var(--pl-color-text);
  margin: 0 0 var(--pl-space-1);
  line-height: 1.2;
}

.pl-section-header p {
  font-size: 17px;
  color: var(--pl-color-muted);
  margin: 0;
  line-height: 1.6;
}

/* --------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------- */

.pl-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 20px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--pl-radius-sm);
  border: 1px solid transparent;
  text-decoration: none;
  cursor: pointer;
  transition: background-color .15s ease, border-color .15s ease, color .15s ease;
  line-height: 1.2;
}

.pl-btn i,
.pl-btn .fa,
.pl-btn .fas {
  font-size: 14px;
}

.pl-btn-primary {
  background: var(--pl-color-primary);
  border-color: var(--pl-color-primary);
  color: #FFFFFF;
}

.pl-btn-primary:hover {
  background: #0c3c66;
  border-color: #0c3c66;
  color: #FFFFFF;
  text-decoration: none;
}

.pl-btn-outline {
  background: var(--pl-color-bg);
  border-color: var(--pl-color-border);
  color: var(--pl-color-text);
}

.pl-btn-outline:hover {
  border-color: var(--pl-color-primary);
  color: var(--pl-color-primary);
  text-decoration: none;
}

.pl-link {
  color: var(--pl-color-accent);
  font-weight: 600;
  font-size: 15px;
  text-decoration: none;
}

.pl-link:hover {
  color: var(--pl-color-primary);
  text-decoration: underline;
}

.pl-link i,
.pl-link .fa,
.pl-link .fas {
  font-size: 12px;
  margin-left: 4px;
}

/* --------------------------------------------------------------------
   Hero
   -------------------------------------------------------------------- */

.pl-hero {
  padding-top: var(--pl-space-5);
  margin-bottom: var(--pl-space-6);
}

.pl-hero-media {
  border: 1px solid var(--pl-color-border);
  border-radius: var(--pl-radius);
  overflow: hidden;
  max-width: 720px;
  margin-bottom: var(--pl-space-3);
}

.pl-hero-media img {
  display: block;
  width: 100%;
  height: auto;
}

.pl-hero-tagline {
  font-size: 18px;
  color: var(--pl-color-muted);
  max-width: 640px;
  line-height: 1.6;
  margin: 0 0 var(--pl-space-3);
}

.pl-hero-actions {
  display: flex;
  gap: var(--pl-space-2);
  flex-wrap: wrap;
}

/* --------------------------------------------------------------------
   Statistic block
   -------------------------------------------------------------------- */

.pl-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border: 1px solid var(--pl-color-border);
  border-radius: var(--pl-radius);
  overflow: hidden;
  margin-bottom: var(--pl-space-6);
}

.pl-stat {
  padding: var(--pl-space-3) var(--pl-space-3);
  border-left: 1px solid var(--pl-color-border);
  background: var(--pl-color-bg-secondary);
}

.pl-stat:first-child {
  border-left: none;
}

.pl-stat-value {
  font-size: 30px;
  font-weight: 700;
  color: var(--pl-color-primary);
  line-height: 1.1;
  margin-bottom: 4px;
}

.pl-stat-label {
  font-size: var(--pl-text-caption);
  color: var(--pl-color-muted);
  line-height: 1.4;
}

/* --------------------------------------------------------------------
   Workflow strip
   -------------------------------------------------------------------- */

.pl-workflow {
  display: flex;
  align-items: stretch;
  border: 1px solid var(--pl-color-border);
  border-radius: var(--pl-radius);
  overflow: hidden;
}

.pl-workflow-step {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 10px;
  padding: var(--pl-space-3) var(--pl-space-2);
  border-left: 1px solid var(--pl-color-border);
  background: var(--pl-color-bg);
}

.pl-workflow-step:first-child {
  border-left: none;
}

.pl-workflow-icon {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--pl-color-bg-secondary);
  border: 1px solid var(--pl-color-border);
  color: var(--pl-color-primary);
  font-size: 16px;
}

.pl-workflow-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--pl-color-text);
}

/* --------------------------------------------------------------------
   Tool card
   -------------------------------------------------------------------- */

.pl-tool-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--pl-space-3);
}

.pl-tool-card {
  border: 1px solid var(--pl-color-border);
  border-radius: var(--pl-radius);
  padding: var(--pl-space-3);
  display: flex;
  flex-direction: column;
}

.pl-tool-icon {
  width: 44px;
  height: 44px;
  border-radius: var(--pl-radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--pl-color-primary);
  color: #FFFFFF;
  font-size: 18px;
  margin-bottom: var(--pl-space-2);
}

.pl-tool-card h3 {
  font-size: var(--pl-text-card);
  font-weight: 700;
  color: var(--pl-color-text);
  margin: 0 0 8px;
}

.pl-tool-card p {
  font-size: var(--pl-text-body);
  color: var(--pl-color-muted);
  line-height: 1.6;
  margin: 0 0 var(--pl-space-2);
}

.pl-tool-card ul {
  list-style: none;
  margin: 0 0 var(--pl-space-3);
  padding: 0;
  flex: 1;
}

.pl-tool-card ul li {
  font-size: 14px;
  color: var(--pl-color-text);
  padding: 5px 0 5px 20px;
  position: relative;
}

.pl-tool-card ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 13px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--pl-color-accent);
}

/* --------------------------------------------------------------------
   Feature row (large screenshot + concise module description)
   -------------------------------------------------------------------- */

.pl-feature-row {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: var(--pl-space-5);
  align-items: center;
  margin-bottom: var(--pl-space-6);
}

.pl-feature-row.pl-feature-reverse .pl-feature-media {
  order: 2;
}

.pl-feature-row.pl-feature-reverse .pl-feature-text {
  order: 1;
}

.pl-feature-text .pl-tool-icon {
  margin-bottom: var(--pl-space-2);
}

.pl-feature-text h3 {
  font-size: var(--pl-text-card);
  font-weight: 700;
  color: var(--pl-color-text);
  margin: 0 0 10px;
}

.pl-feature-text p {
  font-size: var(--pl-text-body);
  color: var(--pl-color-muted);
  line-height: 1.6;
  margin: 0 0 var(--pl-space-2);
}

.pl-feature-text ul {
  list-style: none;
  margin: 0 0 var(--pl-space-3);
  padding: 0;
}

.pl-feature-text ul li {
  font-size: 14px;
  color: var(--pl-color-text);
  padding: 5px 0 5px 20px;
  position: relative;
}

.pl-feature-text ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 13px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--pl-color-accent);
}

/* --------------------------------------------------------------------
   Screenshot / browser frame
   -------------------------------------------------------------------- */

.pl-frame {
  border: 1px solid var(--pl-color-border);
  border-radius: var(--pl-radius);
  overflow: hidden;
  background: var(--pl-color-bg);
  display: flex;
  flex-direction: column;
  height: 100%;
}

.pl-frame-bar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 14px;
  background: var(--pl-color-bg-secondary);
  border-bottom: 1px solid var(--pl-color-border);
}

.pl-frame-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--pl-color-border);
}

.pl-frame-body {
  cursor: pointer;
  position: relative;
  display: flex;
  align-items: flex-start;
  justify-content: center;
}

.pl-frame-body img {
  display: block;
  width: 100%;
  height: auto;
}

.pl-frame-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 220px;
  background: var(--pl-color-bg-secondary);
  border: 1px dashed var(--pl-color-border);
  color: var(--pl-color-muted);
}

.pl-frame-placeholder i {
  font-size: 28px;
}

.pl-frame-placeholder span {
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.pl-frame-caption {
  padding: var(--pl-space-2);
  margin-top: auto;
  text-align: left;
}

.pl-frame-caption .pl-viz-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--pl-color-text);
  margin-bottom: 2px;
  text-align: left;
}

.pl-frame-caption .pl-viz-description {
  font-size: var(--pl-text-caption);
  color: var(--pl-color-muted);
  line-height: 1.5;
  text-align: left;
}

.pl-viz-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--pl-space-3);
}

/* --------------------------------------------------------------------
   Publications
   -------------------------------------------------------------------- */

.pl-pub {
  border: 1px solid var(--pl-color-border);
  border-radius: var(--pl-radius);
  padding: var(--pl-space-3);
  display: flex;
  align-items: flex-start;
  gap: var(--pl-space-3);
}

.pl-pub-icon {
  flex: 0 0 auto;
  width: 40px;
  height: 40px;
  border-radius: var(--pl-radius-sm);
  background: var(--pl-color-bg-secondary);
  border: 1px solid var(--pl-color-border);
  color: var(--pl-color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
}

.pl-pub-title {
  font-weight: 600;
  color: var(--pl-color-text);
  margin: 0 0 4px;
}

.pl-pub-meta {
  font-size: var(--pl-text-caption);
  color: var(--pl-color-muted);
  margin: 0 0 8px;
}

/* --------------------------------------------------------------------
   Modal (used for expanding plot previews)
   -------------------------------------------------------------------- */

.pl-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.6);
  opacity: 0;
  visibility: hidden;
  transition: opacity .2s ease;
  z-index: 9998;
}

.pl-overlay.active {
  opacity: 1;
  visibility: visible;
}

.pl-modal {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: min(90vw, 900px);
  max-height: 85vh;
  background: var(--pl-color-bg);
  border-radius: var(--pl-radius);
  border: 1px solid var(--pl-color-border);
  box-shadow: 0 24px 60px rgba(15, 23, 42, 0.25);
  z-index: 9999;
  display: none;
  flex-direction: column;
  overflow: hidden;
}

.pl-modal.active {
  display: flex;
}

.pl-modal.pl-modal--wide {
  width: 98vw;
  height: 96vh;
  max-height: 96vh;
}

.pl-modal.pl-modal--wide .pl-modal-body {
  padding: 0;
}

.pl-modal.pl-modal--wide .pl-modal-body iframe {
  width: 100%;
  height: 100%;
}

.pl-modal.pl-modal--wide .pl-modal-body img {
  width: 100%;
  height: 100%;
}

.pl-modal-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  border-bottom: 1px solid var(--pl-color-border);
  background: var(--pl-color-bg-secondary);
}

.pl-modal-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--pl-color-text);
}

.pl-modal-close {
  background: none;
  border: none;
  font-size: 20px;
  line-height: 1;
  color: var(--pl-color-muted);
  cursor: pointer;
  padding: 4px 8px;
}

.pl-modal-close:hover {
  color: var(--pl-color-text);
}

.pl-modal-body {
  flex: 1;
  overflow: auto;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--pl-space-2);
  min-height: 0;
}

.pl-modal-body img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

.pl-modal-body iframe {
  width: 100%;
  height: 70vh;
  border: none;
}

/* --------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------- */

@media (max-width: 900px) {
  .pl-stats { grid-template-columns: repeat(2, 1fr); }
  .pl-stat:nth-child(3) { border-left: none; }
  .pl-stat:nth-child(odd) { border-left: none; }
  .pl-workflow { flex-wrap: wrap; }
  .pl-workflow-step { flex: 1 1 33%; border-left: none; border-top: 1px solid var(--pl-color-border); }
  .pl-workflow-step:nth-child(-n+3) { border-top: none; }
  .pl-tool-grid { grid-template-columns: 1fr; }
  .pl-viz-grid { grid-template-columns: repeat(2, 1fr); }
  .pl-feature-row,
  .pl-feature-row.pl-feature-reverse {
    grid-template-columns: 1fr;
  }
  .pl-feature-row .pl-feature-media,
  .pl-feature-row.pl-feature-reverse .pl-feature-media {
    order: 1;
  }
  .pl-feature-row .pl-feature-text,
  .pl-feature-row.pl-feature-reverse .pl-feature-text {
    order: 2;
  }
}

@media (max-width: 640px) {
  .pl-nav-inner { padding: 0 var(--pl-space-2); }
  .pl-nav-inner nav { flex: 1 1 auto; min-width: 0; }
  .pl-nav-links {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    flex-wrap: nowrap;
  }
  .pl-nav-links li { flex: 0 0 auto; }
  .pl-nav-links li a { padding: 0 10px; font-size: 14px; white-space: nowrap; }
  .pl-page { padding: var(--pl-space-5) var(--pl-space-2) var(--pl-space-6); }
  .pl-stats { grid-template-columns: 1fr 1fr; }
  .pl-viz-grid { grid-template-columns: 1fr; }
}