:root {
  --bg: #f4f0e8;
  --bg-soft: #fbf8f2;
  --surface: rgba(255, 255, 255, 0.9);
  --surface-strong: #ffffff;
  --line: rgba(24, 48, 73, 0.16);
  --line-strong: rgba(24, 48, 73, 0.26);
  --ink: #162333;
  --muted: #5d6774;
  --navy: #183049;
  --navy-soft: #33506e;
  --accent: #8a5b3d;
  --accent-soft: #d8c2b1;
  --success: #2f6d57;
  --success-soft: #dfeee7;
  --warning: #8c5b11;
  --warning-soft: #f7e7c3;
  --radius-xl: 24px;
  --radius-lg: 18px;
  --radius-md: 12px;
  --shadow: 0 16px 40px rgba(24, 48, 73, 0.08);
  --content-width: min(1160px, calc(100vw - 32px));
  --heading-font: "Source Han Serif SC", "Noto Serif SC", "Songti SC", "Iowan Old Style", serif;
  --body-font: "Noto Sans SC", "PingFang SC", "Helvetica Neue", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at top right, rgba(138, 91, 61, 0.08), transparent 22%),
    linear-gradient(180deg, #f6f2ea 0%, #f4f0e8 100%);
  color: var(--ink);
  font-family: var(--body-font);
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
select,
textarea {
  font: inherit;
}

.project-page {
  width: var(--content-width);
  margin: 0 auto;
  padding: 26px 0 56px;
}

.project-topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 0 16px;
  border-bottom: 1px solid var(--line);
  background: rgba(244, 240, 232, 0.9);
  backdrop-filter: blur(10px);
}

.project-brand {
  display: grid;
  gap: 2px;
  color: var(--navy);
}

.project-brand span {
  color: var(--accent);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.project-brand strong {
  font-size: 1rem;
}

.project-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 14px;
}

.project-nav a {
  color: rgba(24, 48, 73, 0.82);
  font-size: 0.94rem;
}

.project-nav a:hover {
  color: var(--navy);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.project-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(260px, 0.8fr);
  gap: 24px;
  align-items: start;
  padding: 28px 0 24px;
  border-bottom: 1px solid var(--line);
}

.hero-copy,
.hero-side {
  min-width: 0;
}

.eyebrow {
  margin: 0;
  color: var(--accent);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.project-hero h1,
.hero-side h2,
.section-title,
.panel-title,
.item-title,
.viewer-title,
.tab-button,
.metric-value {
  font-family: var(--heading-font);
}

.project-hero h1 {
  margin: 14px 0 0;
  color: var(--navy);
  font-size: clamp(2.4rem, 4.8vw, 4rem);
  line-height: 1.04;
}

.hero-lead {
  margin: 18px 0 0;
  max-width: 30ch;
  font-size: clamp(1.1rem, 2vw, 1.5rem);
  line-height: 1.6;
}

.hero-summary {
  margin: 18px 0 0;
  max-width: 62ch;
  color: var(--muted);
  line-height: 1.9;
}

.hero-side {
  padding: 18px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.hero-side h2 {
  margin: 0 0 14px;
  color: var(--navy);
  font-size: 1.2rem;
}

.meta-list,
.bullet-list {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
  line-height: 1.9;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.action-link,
.ghost-link,
.mini-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  font-weight: 700;
}

.action-link {
  padding: 12px 18px;
  background: var(--navy);
  color: #fff;
}

.action-link:hover {
  background: var(--navy-soft);
}

.ghost-link {
  padding: 12px 18px;
  color: var(--navy);
  background: rgba(24, 48, 73, 0.08);
}

.ghost-link:hover {
  background: rgba(24, 48, 73, 0.12);
}

.mini-link {
  padding: 9px 14px;
  color: var(--navy);
  background: rgba(24, 48, 73, 0.08);
  font-size: 0.92rem;
}

.project-metrics {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin-top: 22px;
}

.metric-card {
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.metric-value {
  color: var(--navy);
  font-size: 1.6rem;
}

.metric-label {
  margin-top: 4px;
  color: var(--muted);
  font-size: 0.92rem;
}

.workspace {
  display: grid;
  grid-template-columns: minmax(260px, 0.33fr) minmax(0, 0.67fr);
  gap: 18px;
  margin-top: 28px;
}

.list-panel,
.viewer-panel {
  min-width: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.panel-header {
  display: grid;
  gap: 8px;
  padding: 20px 22px 16px;
  border-bottom: 1px solid rgba(24, 48, 73, 0.08);
}

.panel-title {
  margin: 0;
  color: var(--navy);
  font-size: 1.24rem;
}

.panel-desc {
  margin: 0;
  color: var(--muted);
  line-height: 1.75;
}

.filter-row,
.tab-row,
.viewer-actions,
.badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.filter-row,
.tab-row {
  padding: 14px 22px 0;
}

.filter-button,
.tab-button {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 8px 14px;
  background: var(--bg-soft);
  color: var(--navy);
  cursor: pointer;
  transition:
    border-color 180ms ease,
    background-color 180ms ease,
    transform 180ms ease;
}

.filter-button:hover,
.tab-button:hover,
.filter-button.is-active,
.tab-button.is-active {
  border-color: var(--line-strong);
  background: #fff;
  transform: translateY(-1px);
}

.item-list {
  display: grid;
  gap: 12px;
  padding: 16px 18px 18px;
}

.item-button {
  width: 100%;
  display: grid;
  gap: 8px;
  padding: 16px;
  text-align: left;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, #fff 0%, #fbf8f3 100%);
  cursor: pointer;
  transition:
    border-color 180ms ease,
    transform 180ms ease,
    box-shadow 180ms ease;
}

.item-button:hover,
.item-button.is-active {
  border-color: var(--line-strong);
  transform: translateY(-1px);
  box-shadow: 0 10px 20px rgba(24, 48, 73, 0.08);
}

.item-title {
  margin: 0;
  color: var(--navy);
  font-size: 1.08rem;
  line-height: 1.45;
}

.item-meta,
.item-summary,
.viewer-meta,
.empty-state,
.note-line {
  color: var(--muted);
  line-height: 1.75;
}

.viewer-panel {
  display: grid;
  grid-template-rows: auto auto 1fr;
  min-height: 720px;
}

.viewer-head {
  display: grid;
  gap: 10px;
  padding: 20px 22px 0;
}

.viewer-title {
  margin: 0;
  color: var(--navy);
  font-size: 1.45rem;
}

.viewer-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 22px 0;
}

.badge {
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
  padding: 5px 10px;
  font-size: 0.82rem;
  font-weight: 700;
}

.badge.primary {
  background: rgba(24, 48, 73, 0.1);
  color: var(--navy);
}

.badge.success {
  background: var(--success-soft);
  color: var(--success);
}

.badge.warning {
  background: var(--warning-soft);
  color: var(--warning);
}

.badge.neutral {
  background: rgba(24, 48, 73, 0.08);
  color: var(--muted);
}

.viewer-surface {
  margin: 16px 22px 22px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: linear-gradient(180deg, #fff 0%, #fbf8f3 100%);
  overflow: auto;
}

.viewer-markdown,
.viewer-rich {
  color: var(--ink);
  line-height: 1.9;
}

.viewer-markdown h1,
.viewer-markdown h2,
.viewer-markdown h3,
.viewer-rich h1,
.viewer-rich h2,
.viewer-rich h3 {
  color: var(--navy);
  font-family: var(--heading-font);
}

.viewer-markdown h1,
.viewer-rich h1 {
  font-size: 1.8rem;
}

.viewer-markdown h2,
.viewer-rich h2 {
  margin-top: 28px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(24, 48, 73, 0.1);
  font-size: 1.34rem;
}

.viewer-markdown h3,
.viewer-rich h3 {
  margin-top: 24px;
  font-size: 1.12rem;
}

.viewer-markdown p,
.viewer-markdown li,
.viewer-rich p,
.viewer-rich li {
  margin: 0 0 12px;
}

.viewer-markdown ul,
.viewer-markdown ol,
.viewer-rich ul,
.viewer-rich ol {
  padding-left: 20px;
}

.viewer-markdown blockquote,
.viewer-rich blockquote {
  margin: 18px 0;
  padding: 12px 16px;
  border-left: 3px solid var(--accent);
  background: rgba(138, 91, 61, 0.08);
}

.viewer-markdown pre,
.viewer-rich pre {
  overflow: auto;
  padding: 14px;
  border-radius: var(--radius-md);
  background: #faf6ef;
}

.info-grid {
  display: grid;
  gap: 14px;
}

.info-grid.two-col {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.info-card,
.quote-card,
.note-card,
.annotation-card {
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: #fff;
}

.info-card h3,
.quote-card h3,
.annotation-group h3 {
  margin: 0 0 10px;
  color: var(--navy);
  font-size: 1.05rem;
}

.quote-card blockquote {
  margin: 0;
  padding: 0;
  border: none;
  background: none;
  color: var(--ink);
}

.annotation-group + .annotation-group {
  margin-top: 22px;
}

.annotation-card + .annotation-card {
  margin-top: 10px;
}

.annotation-text {
  margin: 10px 0 0;
  padding: 12px 14px;
  border-left: 3px solid var(--navy);
  background: rgba(24, 48, 73, 0.05);
  color: var(--ink);
}

.annotation-comment {
  margin: 10px 0 0;
  color: var(--muted);
}

.iframe-shell {
  display: grid;
  gap: 14px;
}

.iframe-preview {
  width: 100%;
  min-height: 640px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: #fff;
}

.page-footer {
  margin-top: 24px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.94rem;
}

.project-hero.compact {
  grid-template-columns: minmax(0, 1.5fr) minmax(240px, 0.72fr);
  padding-bottom: 18px;
}

.demo-stage,
.library-stage {
  margin-top: 24px;
}

.panel-shell {
  border: 1px solid var(--line);
  border-radius: var(--radius-xl);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.assistant-layout {
  display: grid;
  grid-template-columns: minmax(280px, 0.34fr) minmax(0, 0.66fr);
  gap: 18px;
  padding: 18px;
}

.control-panel,
.response-panel,
.outline-panel,
.media-panel {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, #fff 0%, #fbf8f3 100%);
}

.control-panel,
.response-panel,
.outline-panel,
.media-panel {
  padding: 18px;
}

.control-stack,
.response-stack,
.card-stack {
  display: grid;
  gap: 14px;
}

.query-form {
  display: grid;
  gap: 12px;
}

.query-row,
.search-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.query-input,
.search-input {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: #fff;
  color: var(--ink);
}

.query-input:focus,
.search-input:focus {
  outline: 2px solid rgba(24, 48, 73, 0.12);
  border-color: var(--line-strong);
}

.query-submit,
.upload-label {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--navy);
  color: #fff;
  cursor: pointer;
  font-weight: 700;
}

.query-submit:hover,
.upload-label:hover {
  background: var(--navy-soft);
}

.upload-label input {
  display: none;
}

.prompt-grid,
.source-grid,
.result-grid,
.media-grid {
  display: grid;
  gap: 10px;
}

.prompt-grid.inline {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.prompt-button,
.source-button,
.filter-chip {
  display: inline-flex;
  width: 100%;
  align-items: flex-start;
  justify-content: flex-start;
  gap: 8px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: #fff;
  color: var(--navy);
  cursor: pointer;
  text-align: left;
}

.prompt-button:hover,
.source-button:hover,
.filter-chip:hover,
.filter-chip.is-active {
  border-color: var(--line-strong);
  transform: translateY(-1px);
}

.prompt-button strong,
.source-button strong,
.figure-title,
.response-title {
  font-family: var(--heading-font);
}

.prompt-button span,
.source-button span,
.support-text,
.result-note {
  color: var(--muted);
  line-height: 1.65;
}

.response-title {
  margin: 0;
  color: var(--navy);
  font-size: 1.32rem;
}

.response-surface {
  display: grid;
  gap: 14px;
}

.response-block,
.insight-card,
.source-card,
.result-card,
.figure-card {
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: #fff;
}

.response-block h3,
.insight-card h3,
.source-card h3,
.result-card h3,
.outline-panel h3,
.figure-card h3 {
  margin: 0 0 10px;
  color: var(--navy);
  font-size: 1.03rem;
}

.response-block ul,
.insight-card ul {
  margin: 0;
  padding-left: 18px;
  color: var(--ink);
  line-height: 1.8;
}

.source-grid.cols-2,
.media-grid.cols-2,
.result-grid.cols-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.reader-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(220px, 0.32fr);
  gap: 18px;
}

.outline-panel {
  align-self: start;
  position: sticky;
  top: 12px;
}

.outline-list {
  display: grid;
  gap: 8px;
}

.outline-link {
  display: block;
  color: var(--muted);
  line-height: 1.55;
}

.outline-link.depth-1 {
  color: var(--navy);
  font-weight: 700;
}

.outline-link.depth-2 {
  padding-left: 10px;
}

.outline-link.depth-3 {
  padding-left: 20px;
}

.outline-link:hover {
  color: var(--navy);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.inline-form {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.inline-form .search-input {
  flex: 1 1 240px;
}

.viewer-embed {
  width: 100%;
  min-height: 640px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: #fff;
}

.figure-card img {
  width: 100%;
  display: block;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: #fff;
}

.figure-meta,
.split-note {
  color: var(--muted);
  line-height: 1.7;
}

.stat-line {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.stat-pill {
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
  padding: 8px 12px;
  background: rgba(24, 48, 73, 0.08);
  color: var(--navy);
  font-size: 0.9rem;
  font-weight: 700;
}

.empty-card {
  padding: 18px;
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius-lg);
  color: var(--muted);
  background: rgba(255, 255, 255, 0.7);
}

@media (max-width: 980px) {
  .project-hero,
  .workspace,
  .project-metrics,
  .info-grid.two-col,
  .assistant-layout,
  .reader-layout,
  .source-grid.cols-2,
  .media-grid.cols-2,
  .result-grid.cols-2 {
    grid-template-columns: 1fr;
  }

  .project-nav {
    justify-content: flex-start;
  }

  .viewer-panel {
    min-height: 0;
  }

  .outline-panel {
    position: static;
  }
}

@media (max-width: 640px) {
  .project-page {
    width: min(100vw - 24px, 100%);
    padding-top: 18px;
  }

  .project-topbar {
    align-items: flex-start;
    flex-direction: column;
  }

  .project-hero h1 {
    font-size: 2.45rem;
  }

  .viewer-surface {
    margin: 14px 16px 16px;
    padding: 16px;
  }

  .panel-header,
  .viewer-head,
  .viewer-toolbar,
  .filter-row,
  .tab-row {
    padding-left: 16px;
    padding-right: 16px;
  }

  .item-list {
    padding: 16px;
  }

  .iframe-preview {
    min-height: 500px;
  }

  .assistant-layout {
    padding: 14px;
  }

  .control-panel,
  .response-panel,
  .outline-panel,
  .media-panel {
    padding: 16px;
  }

  .prompt-grid.inline {
    grid-template-columns: 1fr;
  }

  .viewer-embed {
    min-height: 460px;
  }
}