/* nephos — the cloud of witnesses — academic red */

:root {
  --bg: #0f1112;
  --surface: #1a1618;
  --surface-hover: #2a2224;
  --ink: #e8e4df;
  --ink-soft: #a8a196;
  --ink-faint: #6b6560;
  --rule: #2a2225;
  --accent: #b04040;
  --accent-soft: rgba(176, 64, 64, 0.15);
  --accent-hover: #d45050;
  --source-bg: #161214;
  --source-border: #2a2022;
  --check-blue: #b04040;

  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, "Times New Roman", serif;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  --measure: 44rem;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }

/* Full-page background image */
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  position: relative;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    linear-gradient(to bottom, rgba(15,17,20,0.55) 0%, rgba(15,17,20,0.85) 40%, rgba(15,17,20,0.97) 70%, var(--bg) 100%),
    url('/assets/og-image.jpg') center top / cover no-repeat;
  filter: grayscale(100%);
  pointer-events: none;
  z-index: 0;
}

main {
  flex: 1;
  max-width: var(--measure);
  width: 100%;
  margin: 0 auto;
  padding: 0 1.25rem;
  display: flex;
  flex-direction: column;
  position: relative;
  z-index: 1;
}

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

/* ---------- masthead ---------- */

.masthead {
  padding: 2.5rem 0 1.25rem;
  text-align: center;
  margin-bottom: 0.5rem;
}

.masthead .label {
  margin: 0 0 0.3rem;
  font-family: var(--sans);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
}

.masthead h1 {
  margin: 0;
  font-size: 1.7rem;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.01em;
  text-shadow: 0 2px 12px rgba(0,0,0,0.5);
}

.masthead .subtitle {
  margin: 0.4rem 0 0;
  font-style: italic;
  color: var(--ink);
  font-size: 0.95rem;
  text-shadow: 0 1px 8px rgba(0,0,0,0.4);
}

.masthead .subtitle-count {
  margin: 0.2rem 0 0;
  font-family: var(--sans);
  font-size: 0.75rem;
  color: var(--ink-soft);
  letter-spacing: 0.04em;
}

/* ---------- filter toggle ---------- */

.filter-toggle {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 0.75rem;
  padding: 0.4rem 0.9rem;
  font-family: var(--sans);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--ink-faint);
  background: rgba(15, 17, 20, 0.6);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--rule);
  border-radius: 999px;
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
}

.filter-toggle:hover,
.filter-toggle[aria-expanded="true"] {
  color: var(--accent);
  border-color: var(--accent);
}

/* ---------- filter panel ---------- */

.filter-panel {
  background: rgba(26, 29, 34, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--rule);
  border-radius: 0.6rem;
  padding: 1rem 1.25rem;
  margin-bottom: 1rem;
  animation: slideDown 0.15s ease-out;
}

@keyframes slideDown {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Tradition columns */
.filter-traditions {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 1rem;
}

.tradition-column h3 {
  font-family: var(--sans);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 0.5rem;
  font-weight: 700;
  padding-bottom: 0.35rem;
  border-bottom: 1px solid var(--rule);
  cursor: pointer;
  user-select: none;
  display: flex;
  align-items: center;
  gap: 6px;
}

.tradition-column h3 input[type="checkbox"] {
  accent-color: var(--check-blue);
  width: 14px;
  height: 14px;
  cursor: pointer;
}

.tradition-column .author-list {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.tradition-column .author-list label {
  font-family: var(--sans);
  font-size: 0.82rem;
  color: var(--ink-soft);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 0.15rem 0;
  transition: color 0.12s;
}

.tradition-column .author-list label:hover {
  color: var(--ink);
}

.tradition-column .author-list input[type="checkbox"] {
  accent-color: var(--check-blue);
  width: 14px;
  height: 14px;
  cursor: pointer;
  flex-shrink: 0;
}

.filter-actions {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--rule);
}

.btn-filter {
  font-family: var(--sans);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-faint);
  background: none;
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 0.35rem 0.75rem;
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
}

.btn-filter:hover {
  color: var(--accent);
  border-color: var(--accent);
}

/* ---------- conversation ---------- */

#conversation {
  flex: 1;
  overflow-y: auto;
  padding-bottom: 1rem;
  min-height: 0;
}

.msg {
  margin-bottom: 1.75rem;
  animation: fadeIn 0.2s ease-in;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

.msg-question {
  padding: 0.8rem 1rem;
  background: rgba(26, 29, 34, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-radius: 0.5rem;
  border: 1px solid var(--rule);
  font-family: var(--sans);
  font-size: 0.95rem;
  color: var(--ink);
  margin-bottom: 0.75rem;
}

.msg-answer {
  padding: 0 0.25rem;
  line-height: 1.75;
}

.msg-answer b {
  display: inline;
  color: var(--accent);
  font-weight: 600;
}

.msg-answer a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid var(--rule);
}

.msg-answer a:hover {
  border-bottom-color: var(--accent);
  text-decoration: none;
}

.msg-answer h3 {
  font-family: var(--sans);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--accent);
  margin: 1.25rem 0 0.4rem;
  letter-spacing: -0.01em;
}

.msg-answer h3:first-child {
  margin-top: 0;
}

.msg-answer h4 {
  font-family: var(--sans);
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--ink);
  margin: 1rem 0 0.3rem;
}

.msg-answer p {
  margin: 0 0 0.6rem;
}

.msg-answer blockquote {
  margin: 0.5rem 0 0.75rem;
  padding: 0.6rem 1rem;
  border-left: 3px solid var(--accent);
  background: rgba(176, 64, 64, 0.06);
  border-radius: 0 0.3rem 0.3rem 0;
  font-style: italic;
  color: var(--ink-soft);
  font-size: 0.95rem;
  line-height: 1.65;
}

.msg-answer blockquote p {
  margin: 0;
}

.msg-answer ul,
.msg-answer ol {
  margin: 0.4rem 0 0.75rem;
  padding-left: 1.5rem;
}

.msg-answer li {
  margin-bottom: 0.3rem;
  line-height: 1.6;
}

.msg-answer strong {
  color: var(--ink);
  font-weight: 700;
}

/* ---------- source cards ---------- */

.sources-section {
  margin-top: 1rem;
  border-top: 1px solid var(--rule);
  padding-top: 0.75rem;
}

.sources-heading {
  font-family: var(--sans);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin: 0 0 0.5rem;
  font-weight: 600;
}

.source-card {
  background: rgba(22, 26, 31, 0.9);
  border: 1px solid var(--source-border);
  border-radius: 0.5rem;
  margin-bottom: 0.5rem;
  overflow: hidden;
}

.source-card-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 0.75rem;
  cursor: pointer;
  font-family: var(--sans);
  font-size: 0.82rem;
  color: var(--ink-soft);
  transition: color 0.15s;
}

.source-card-header:hover {
  color: var(--ink);
}

.source-num {
  color: var(--accent);
  font-weight: 700;
  font-size: 0.75rem;
  flex-shrink: 0;
}

.source-meta {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.source-author {
  font-weight: 600;
  color: var(--ink);
}

.source-expand {
  flex-shrink: 0;
  color: var(--ink-faint);
  font-size: 0.7rem;
  transition: transform 0.2s;
}

.source-card[open] .source-expand {
  transform: rotate(90deg);
}

.source-card-body {
  display: none;
  padding: 0 0.75rem 0.75rem;
  border-top: 1px solid var(--source-border);
}

.source-card[open] .source-card-body {
  display: block;
}

.source-text {
  font-size: 0.85rem;
  line-height: 1.65;
  color: var(--ink-soft);
  margin: 0.5rem 0;
  font-style: italic;
}

.source-actions {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.5rem;
}

.source-link,
.source-copy {
  font-family: var(--sans);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 0.3rem 0.65rem;
  border-radius: 4px;
  border: 1px solid var(--source-border);
  background: none;
  color: var(--accent);
  cursor: pointer;
  text-decoration: none;
  transition: border-color 0.15s;
}

.source-link:hover,
.source-copy:hover {
  border-color: var(--accent);
  text-decoration: none;
}

/* ---------- thinking indicator ---------- */

.thinking {
  color: var(--ink-faint);
  font-style: italic;
  font-size: 0.9rem;
  padding: 0.5rem 0;
}

.thinking::after {
  content: '';
  animation: dots 1.2s steps(4, end) infinite;
}

@keyframes dots {
  0% { content: ''; }
  25% { content: '.'; }
  50% { content: '..'; }
  75% { content: '...'; }
}

/* ---------- answer actions ---------- */

.answer-actions {
  display: flex;
  justify-content: flex-end;
  gap: 0.4rem;
  margin-top: 0.5rem;
  padding-bottom: 0.25rem;
}

.btn-action {
  font-family: var(--sans);
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-faint);
  background: none;
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 0.35rem 0.75rem;
  display: flex;
  align-items: center;
  gap: 4px;
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
}

.btn-action:hover {
  color: var(--accent);
  border-color: var(--accent);
}

/* ---------- input area ---------- */

.input-area {
  position: sticky;
  bottom: 0;
  padding: 1rem 0 calc(1rem + env(safe-area-inset-bottom, 0px));
  background: linear-gradient(transparent, var(--bg) 0.75rem);
}

#question {
  display: block;
  width: 100%;
  padding: 0.85rem 1rem;
  background: rgba(26, 29, 34, 0.9);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--rule);
  border-radius: 0.5rem;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1rem;
  line-height: 1.5;
  resize: none;
  outline: none;
  transition: border-color 0.15s;
}

#question::placeholder {
  color: var(--ink-faint);
  font-style: italic;
}

#question:focus {
  border-color: var(--accent);
}

.input-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 0.5rem;
}

.btn-submit {
  font-family: var(--sans);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--bg);
  background: var(--accent);
  border: none;
  border-radius: 50%;
  width: 2.2rem;
  height: 2.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: opacity 0.15s;
  flex-shrink: 0;
}

.btn-submit:hover { opacity: 0.85; }

.btn-submit:disabled {
  opacity: 0.4;
  cursor: default;
}

.btn-clear {
  font-family: var(--sans);
  font-size: 0.72rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--ink-faint);
  background: none;
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 0.45rem 1rem;
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
}

.btn-clear:hover {
  color: var(--accent);
  border-color: var(--accent);
}

/* ---------- footer ---------- */

.footer {
  position: relative;
  z-index: 1;
  max-width: var(--measure);
  width: 100%;
  margin: 0 auto;
  padding: 1.5rem 1.25rem calc(1.5rem + env(safe-area-inset-bottom, 0px));
  border-top: 1px solid var(--rule);
  text-align: center;
  font-family: var(--sans);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-faint);
}

.footer a { color: var(--ink-faint); text-decoration: none; }
.footer a:hover { color: var(--accent); }
.footer span { margin: 0 0.5rem; }

/* ---------- responsive ---------- */

@media (max-width: 500px) {
  body { font-size: 16px; }
  .masthead { padding: 2rem 0 1rem; }
  .masthead h1 { font-size: 1.35rem; }
  #question { font-size: 16px; }
  .filter-traditions { grid-template-columns: 1fr; }
  .filter-panel { padding: 0.75rem 1rem; }
}

@media (min-width: 768px) {
  .masthead { padding: 3rem 0 1.5rem; }
  .masthead h1 { font-size: 1.9rem; }
  .filter-traditions { grid-template-columns: repeat(4, 1fr); }
}