:root {
  --bg: #f6f8f7;
  --paper: #ffffff;
  --text: #19211d;
  --muted: #66716c;
  --mint: #8fd7c4;
  --line: #dce5e1;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: linear-gradient(180deg, #f9fbfa 0%, var(--bg) 100%);
  color: var(--text);
  font-family: "Avenir Next", "Helvetica Neue", Helvetica, Arial, sans-serif;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 24px;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.9);
  position: sticky;
  top: 0;
  backdrop-filter: blur(8px);
}

.brand {
  font-weight: 600;
  letter-spacing: 0.2px;
}

.topnav {
  display: flex;
  gap: 12px;
  align-items: center;
}

.topnav a {
  color: var(--text);
  text-decoration: none;
  padding: 8px 10px;
  border-radius: 10px;
}

.feedback-link {
  background: #eefaf6;
  border: 1px solid #ccefe4;
}

.container {
  max-width: 1100px;
  margin: 28px auto;
  padding: 0 16px;
}

.card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 20px;
  margin-bottom: 16px;
  box-shadow: 0 8px 30px rgba(18, 33, 28, 0.04);
}

.narrow {
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

.grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.stack {
  display: grid;
  gap: 10px;
}

label {
  color: var(--muted);
  font-size: 14px;
}

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

input, select, textarea {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px 12px;
  background: #fff;
}

textarea {
  width: 100%;
}

button {
  border: 0;
  border-radius: 12px;
  padding: 10px 14px;
  background: var(--mint);
  color: #113228;
  cursor: pointer;
}

button.ghost {
  background: #f1f4f3;
}

pre {
  white-space: pre-wrap;
  word-wrap: break-word;
  margin: 0;
  line-height: 1.5;
}

.muted {
  color: var(--muted);
}

.error {
  color: #a62828;
}

.success {
  color: #1b6a53;
}

.upload-result {
  margin-top: 12px;
  border-radius: 12px;
  padding: 10px 12px;
  border: 1px solid var(--line);
}

.upload-result.ok {
  background: #f1fbf7;
  border-color: #ccefe4;
}

.upload-result.err {
  background: #fff5f5;
  border-color: #f2c4c4;
}

.related-list {
  display: grid;
  gap: 12px;
}

.related-item {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 12px;
  background: #fbfdfc;
}

.related-item h3 {
  margin: 0 0 8px;
  font-size: 16px;
}

.related-item p {
  margin: 4px 0;
}

.source-ref {
  color: var(--muted);
  font-size: 13px;
}

.source-list {
  margin: 0;
  padding-left: 18px;
}

.source-list li {
  margin-bottom: 10px;
}

.hidden {
  display: none;
}

.tiny {
  font-size: 12px;
}

.hero-card h1 {
  margin: 0 0 10px;
  font-size: 28px;
  line-height: 1.2;
}

.workspace-grid {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr;
  gap: 16px;
  align-items: start;
}

.chat-card {
  min-height: 680px;
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 12px;
}

.chat-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.chat-header h2 {
  margin: 0;
}

.chat-messages {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #f9fbfa;
  padding: 14px;
  overflow: auto;
  min-height: 460px;
  max-height: 560px;
  display: grid;
  gap: 10px;
}

.msg {
  border-radius: 14px;
  padding: 10px 12px;
  border: 1px solid var(--line);
}

.msg-user {
  background: #eefaf6;
  border-color: #ccefe4;
}

.msg-assistant {
  background: #ffffff;
}

.msg-role {
  color: var(--muted);
  font-size: 12px;
  margin-bottom: 6px;
}

.msg-text {
  white-space: pre-wrap;
  line-height: 1.45;
}

.msg-extra {
  margin-top: 8px;
  font-size: 13px;
  color: var(--muted);
}

.chat-form {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 10px;
}

.chat-form textarea {
  min-height: 90px;
  resize: vertical;
}

.side-stack {
  display: grid;
  gap: 16px;
}

.card-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.dropzone {
  border: 1px dashed #b9c8c2;
  background: #fcfefd;
  border-radius: 12px;
  padding: 14px;
  text-align: center;
  margin-bottom: 10px;
}

.dropzone.dragover {
  border-color: #7abca9;
  background: #f0fbf7;
}

.dropzone input[type="file"] {
  display: block;
  width: 100%;
  margin-top: 8px;
}

.upload-queue {
  margin: 6px 0 10px;
}

.table-wrap {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th, td {
  padding: 10px 8px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.inline-form {
  display: flex;
  gap: 8px;
  align-items: center;
}

.inline-form.wrap {
  flex-wrap: wrap;
}

.doc-location {
  margin-top: 8px;
}

.doc-location summary {
  cursor: pointer;
  color: var(--muted);
  font-size: 13px;
}

.doc-location > .muted {
  margin: 8px 0;
}

.tiny-btn {
  padding: 6px 10px;
  font-size: 12px;
}

.footer {
  text-align: center;
  color: var(--muted);
  padding: 24px 0 28px;
}

@media (max-width: 860px) {
  .workspace-grid {
    grid-template-columns: 1fr;
  }

  .chat-card {
    min-height: 0;
  }

  .chat-messages {
    min-height: 340px;
    max-height: 420px;
  }

  .chat-form {
    grid-template-columns: 1fr;
  }

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

  .topbar {
    flex-direction: column;
    gap: 10px;
    align-items: flex-start;
  }

  .topnav {
    flex-wrap: wrap;
  }
}