:root {
  --cream: #fffde8;
  --ink: #191a17;
  --muted: #74766d;
  --line: #dfddc5;
  --lavender: #edcffd;
  --orange: #ffa43b;
  --green: #00594d;
  --serif: Georgia, "Times New Roman", Times, serif;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--ink);
  font-family: var(--sans);
}

* {
  box-sizing: border-box;
}

body {
  background:
    radial-gradient(circle at 12% 10%, rgba(237, 207, 253, 0.34), transparent 18rem),
    radial-gradient(circle at 92% 5%, rgba(255, 164, 59, 0.18), transparent 22rem),
    var(--cream);
  margin: 0;
  min-height: 100vh;
}

button,
input {
  font: inherit;
}

button {
  cursor: pointer;
}

.chat-shell {
  margin: 0 auto;
  max-width: 1480px;
  padding: clamp(20px, 4vw, 58px);
}

.hero,
.layout {
  display: grid;
  gap: 20px;
  grid-template-columns: minmax(0, 1fr) 360px;
}

.hero {
  align-items: end;
  margin-bottom: 22px;
}

.hero > div,
.source-card,
.library,
.chat-card {
  background: rgba(255, 253, 232, 0.9);
  border: 3px solid var(--ink);
  border-radius: 28px;
}

.hero > div {
  border-color: var(--line);
  padding: clamp(28px, 5vw, 58px);
}

.source-card {
  background: var(--ink);
  color: var(--cream);
  padding: 28px;
}

.eyebrow {
  color: var(--green);
  font-size: 0.72rem;
  font-weight: 950;
  letter-spacing: 0.15em;
  margin: 0 0 10px;
  text-transform: uppercase;
}

.source-card .eyebrow {
  color: var(--lavender);
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  font-family: var(--serif);
  font-size: clamp(3.1rem, 6vw, 6.6rem);
  font-weight: 500;
  letter-spacing: -0.07em;
  line-height: 0.94;
  margin-bottom: 20px;
  max-width: 920px;
}

.source-card h2 {
  font-family: var(--serif);
  font-size: 4rem;
  font-weight: 500;
  letter-spacing: -0.06em;
  line-height: 0.9;
  margin-bottom: 14px;
}

.lede,
.source-card p,
.source-item p,
.message p,
.hit-card p {
  color: var(--muted);
  font-weight: 800;
  line-height: 1.42;
}

.source-card p {
  color: rgba(255, 253, 232, 0.74);
}

.layout {
  align-items: start;
  grid-template-columns: 390px minmax(0, 1fr);
}

.library,
.chat-card {
  padding: clamp(20px, 3vw, 30px);
}

.section-head h2 {
  font-family: var(--serif);
  font-size: clamp(2rem, 3vw, 3.6rem);
  font-weight: 500;
  letter-spacing: -0.055em;
  line-height: 0.96;
  margin-bottom: 18px;
}

.source-list {
  display: grid;
  gap: 10px;
}

.source-item {
  border: 2px solid var(--line);
  border-radius: 18px;
  padding: 14px;
}

.source-item h3 {
  font-size: 1rem;
  letter-spacing: -0.02em;
  line-height: 1.1;
  margin-bottom: 8px;
}

.source-item p {
  font-size: 0.88rem;
  margin-bottom: 0;
}

.suggestions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 18px;
}

.mode-row {
  align-items: center;
  background: rgba(25, 26, 23, 0.06);
  border: 2px solid var(--line);
  border-radius: 999px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 14px;
  padding: 8px 10px;
}

.mode-row span,
.mode-row label {
  font-weight: 950;
}

.mode-row span {
  color: var(--green);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.mode-row label {
  align-items: center;
  background: var(--cream);
  border: 2px solid var(--line);
  border-radius: 999px;
  display: inline-flex;
  gap: 6px;
  padding: 8px 12px;
}

.mode-row input {
  accent-color: var(--ink);
}

.suggestions button,
.chat-form button,
.hit-card button {
  background: var(--ink);
  border: 3px solid var(--ink);
  border-radius: 999px;
  color: var(--cream);
  font-weight: 950;
  padding: 10px 14px;
}

.suggestions button:nth-child(2),
.suggestions button:nth-child(4) {
  background: var(--lavender);
  color: var(--ink);
}

.chat-log {
  display: grid;
  gap: 16px;
  max-height: 62vh;
  overflow: auto;
  padding-right: 8px;
}

.message {
  border-radius: 24px;
  padding: 18px;
}

.message.assistant {
  background: rgba(25, 26, 23, 0.06);
}

.message.user {
  background: var(--lavender);
  justify-self: end;
  max-width: 760px;
}

.message h3 {
  font-size: 1.32rem;
  margin-bottom: 8px;
}

.answer-summary {
  color: var(--ink);
  font-size: 1.05rem;
  font-weight: 900;
  line-height: 1.45;
}

.evidence-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 8px 0 14px;
}

.evidence-strip span {
  background: var(--cream);
  border: 2px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.86rem;
  font-weight: 950;
  padding: 7px 10px;
}

.evidence-strip strong {
  color: var(--ink);
  text-transform: capitalize;
}

.answer-grid {
  display: grid;
  gap: 12px;
  margin-top: 16px;
}

.answer-grid section {
  background: rgba(255, 253, 232, 0.72);
  border: 2px solid var(--line);
  border-radius: 18px;
  padding: 14px;
}

.answer-grid h4,
.passage-title {
  margin: 0 0 8px;
}

.answer-grid ul {
  color: var(--muted);
  font-weight: 850;
  line-height: 1.42;
  margin: 0;
  padding-left: 20px;
}

.answer-grid li + li {
  margin-top: 6px;
}

.passage-title {
  margin-top: 18px;
}

.hit-list {
  display: grid;
  gap: 10px;
  margin-top: 14px;
}

.hit-card {
  background: rgba(255, 253, 232, 0.72);
  border: 2px solid var(--line);
  border-radius: 18px;
  padding: 14px;
}

.hit-card h4 {
  margin: 0 0 8px;
}

.quote {
  border-left: 4px solid var(--orange);
  color: var(--ink);
  font-weight: 850;
  margin: 8px 0 0;
  padding-left: 12px;
}

.claim-line {
  color: var(--ink);
  font-weight: 950;
  margin-bottom: 8px;
}

.claim-line span,
.quote span {
  color: var(--green);
  display: block;
  font-size: 0.72rem;
  font-weight: 950;
  letter-spacing: 0.12em;
  margin-bottom: 4px;
  text-transform: uppercase;
}

.chat-form {
  display: grid;
  gap: 12px;
  grid-template-columns: minmax(0, 1fr) auto;
  margin-top: 18px;
}

.chat-form input {
  background: var(--cream);
  border: 3px solid var(--ink);
  border-radius: 999px;
  color: var(--ink);
  font-weight: 850;
  outline: 0;
  padding: 14px 18px;
}

.chat-form button:disabled {
  opacity: 0.55;
}

.muted {
  color: var(--muted);
  font-weight: 800;
}

code {
  background: rgba(25, 26, 23, 0.08);
  border-radius: 8px;
  padding: 2px 6px;
}

@media (max-width: 980px) {
  .hero,
  .layout,
  .chat-form {
    grid-template-columns: 1fr;
  }

  .chat-log {
    max-height: none;
  }
}