:root {
  color-scheme: light;
  --bg: #f6f7f9;
  --panel: #ffffff;
  --text: #172033;
  --muted: #667085;
  --line: #dce3ee;
  --primary: #315f8f;
  --primary-dark: #203f61;
  --green: #27815f;
  --amber: #b7791f;
  --soft-blue: #eef4f8;
  --shadow: 0 10px 26px rgba(23, 32, 51, 0.06);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Inter, "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
}

button,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.55;
}

.topbar {
  min-height: 104px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px 28px;
  background: #fff;
  border-bottom: 1px solid var(--line);
}

.topbar-main {
  min-width: 0;
}

.platform-label {
  margin-bottom: 6px;
  color: #344054;
  font-size: 13px;
  font-weight: 800;
}

.breadcrumb {
  display: flex;
  gap: 9px;
  align-items: center;
  color: var(--muted);
  font-size: 13px;
}

.breadcrumb b {
  color: #b3bdcc;
  font-weight: 500;
}

.topbar h1 {
  margin: 8px 0 4px;
  font-size: clamp(19px, 1.55vw, 24px);
  letter-spacing: 0;
}

.topbar p {
  margin: 0;
  color: var(--muted);
}

.session-panel {
  min-width: 180px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #f8fafc;
}

.session-panel span,
.session-panel strong,
.session-panel p {
  display: block;
}

.session-panel span {
  margin-bottom: 4px;
  color: #56667a;
  font-size: 13px;
  font-weight: 700;
}

.session-panel strong {
  font-size: 15px;
}

.session-panel p {
  margin-top: 5px;
  color: var(--primary-dark);
  font-weight: 800;
}

.workspace {
  display: grid;
  grid-template-columns: 224px minmax(0, 1fr) 292px;
  gap: 14px;
  height: calc(100vh - 104px);
  min-height: 680px;
  padding: 14px;
}

.step-nav,
.ai-assistant,
.main-panel {
  overflow: auto;
}

.step-nav,
.ai-assistant {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 12px;
}

.nav-title {
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
  margin: 2px 0 12px;
}

.nav-title.sub {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
}

.learning-flow {
  display: grid;
  gap: 8px;
}

.learning-flow div {
  display: grid;
  grid-template-columns: 18px 1fr;
  gap: 8px;
  align-items: center;
  min-height: 28px;
  color: var(--muted);
  font-size: 13px;
}

.learning-flow span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 1px solid #cbd5e1;
  background: #fff;
}

.learning-flow .done span {
  background: var(--green);
  border-color: var(--green);
}

.learning-flow .active {
  color: var(--primary-dark);
  font-weight: 800;
}

.learning-flow .active span {
  background: #fff;
  border: 3px solid var(--primary);
}

.step-item {
  width: 100%;
  display: grid;
  grid-template-columns: 30px 1fr;
  gap: 8px 10px;
  align-items: center;
  margin-bottom: 6px;
  padding: 10px;
  color: var(--text);
  text-align: left;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 6px;
}

.step-item small {
  grid-column: 2;
  color: var(--muted);
  font-size: 12px;
}

.step-index {
  width: 26px;
  height: 26px;
  display: inline-grid;
  place-items: center;
  border-radius: 50%;
  background: #eef2f7;
  color: #526071;
  font-weight: 800;
}

.step-item.active {
  background: #f1f5f8;
  border-color: #c9d5df;
}

.step-item.active .step-index,
.step-item.done .step-index {
  color: #fff;
  background: var(--primary);
}

.step-item.done {
  color: var(--primary-dark);
}

.main-panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 6px;
  box-shadow: var(--shadow);
}

.step-page {
  min-height: 100%;
  padding: clamp(18px, 2vw, 26px);
}

.course-task {
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  gap: 16px;
  align-items: center;
  margin-bottom: 22px;
  padding: 14px 16px;
  border: 1px solid #d9e1ea;
  border-left: 4px solid var(--primary);
  border-radius: 6px;
  background: #f8fafc;
}

.course-task span,
.course-task strong {
  display: block;
}

.course-task span {
  margin-bottom: 4px;
  color: var(--muted);
  font-size: 12px;
  font-weight: 800;
}

.course-task strong {
  color: var(--text);
}

.course-task p {
  margin: 0;
  color: #475467;
}

.section-head {
  max-width: 780px;
  margin-bottom: 22px;
}

.eyebrow,
.card-kicker {
  color: #667085;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0;
}

h2 {
  margin: 8px 0 8px;
  font-size: clamp(21px, 1.9vw, 25px);
  letter-spacing: 0;
}

h3 {
  margin: 8px 0 10px;
  font-size: 17px;
  letter-spacing: 0;
}

h4 {
  margin: 16px 0 8px;
}

p {
  line-height: 1.65;
}

.section-head p,
.dataset-card p,
.assistant-head p,
.design-card p {
  color: var(--muted);
}

.research-input {
  width: 100%;
  min-height: 158px;
  resize: vertical;
  padding: 18px;
  border: 1px solid #cfd8e6;
  border-radius: 6px;
  outline: none;
  background: #fbfcff;
  color: var(--text);
  line-height: 1.75;
  font-size: 16px;
}

.research-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(47, 111, 237, 0.1);
}

.primary,
.secondary {
  min-height: 38px;
  padding: 0 16px;
  border-radius: 6px;
  border: 1px solid transparent;
  font-weight: 700;
}

.primary {
  color: #fff;
  background: var(--primary);
}

.primary:hover {
  background: #254d76;
}

.secondary {
  color: var(--primary-dark);
  background: #fff;
  border-color: #c5d3ea;
}

.big {
  margin: 16px 0;
  min-height: 46px;
  padding: 0 20px;
}

.analysis-loader {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 8px 0 18px;
  color: var(--muted);
}

.analysis-loader span {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--primary);
  animation: pulse 0.9s infinite alternate;
}

.analysis-loader span:nth-child(2) {
  animation-delay: 0.15s;
}

.analysis-loader span:nth-child(3) {
  animation-delay: 0.3s;
}

@keyframes pulse {
  to {
    opacity: 0.25;
    transform: translateY(-5px);
  }
}

.grid {
  display: grid;
  gap: 16px;
}

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

.design-card,
.model-card,
.result-card,
.chart-grid article,
.interpret-grid article,
.question-box,
.conclusion {
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  padding: 16px;
}

.design-card dl {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: 11px;
  margin: 18px 0 0;
}

.design-card dt {
  color: var(--muted);
}

.design-card dd {
  margin: 0;
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 26px;
  margin: 0 6px 6px 0;
  padding: 0 9px;
  color: #475467;
  background: #f7f9fc;
  border: 1px solid #e4e9f1;
  border-radius: 5px;
  font-size: 12px;
  font-weight: 700;
}

.step-footer {
  position: sticky;
  bottom: -26px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin: 28px calc(clamp(18px, 2vw, 26px) * -1) calc(clamp(18px, 2vw, 26px) * -1);
  padding: 14px clamp(18px, 2vw, 26px);
  background: rgba(255, 255, 255, 0.94);
  border-top: 1px solid var(--line);
  backdrop-filter: blur(8px);
}

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

.dataset-card {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  width: 100%;
  padding: 16px;
  text-align: left;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 6px;
}

.dataset-card:hover {
  border-color: var(--primary);
  box-shadow: 0 8px 22px rgba(49, 95, 143, 0.08);
}

.field-row {
  margin-top: 12px;
}

.dataset-meta {
  min-width: 150px;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  justify-content: center;
  gap: 10px;
  color: var(--muted);
}

.dataset-meta strong {
  max-width: 180px;
  padding: 4px 8px;
  color: #344054;
  background: #f3f6f9;
  border: 1px solid #d9e1ea;
  border-radius: 5px;
  font-size: 12px;
  text-align: right;
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  z-index: 10;
  display: grid;
  place-items: center;
  padding: 28px;
  background: rgba(16, 24, 40, 0.38);
}

.modal {
  position: relative;
  width: min(900px, 92vw);
  max-height: 86vh;
  overflow: auto;
  padding: 24px;
  background: #fff;
  border-radius: 6px;
  box-shadow: 0 30px 80px rgba(16, 24, 40, 0.24);
}

.close {
  position: absolute;
  top: 12px;
  right: 14px;
  width: 36px;
  height: 36px;
  border: 0;
  border-radius: 50%;
  background: #eef2f7;
  font-size: 24px;
}

.modal-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px 16px;
  margin: 14px 0;
  padding: 14px;
  background: #f7f9fc;
  border-radius: 6px;
}

.modal-grid b {
  display: block;
  color: var(--muted);
}

.table-wrap {
  overflow: auto;
  margin: 16px 0;
  border: 1px solid var(--line);
  border-radius: 6px;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}

th,
td {
  padding: 11px 12px;
  border-bottom: 1px solid #edf1f7;
  text-align: left;
  white-space: nowrap;
}

th {
  color: #42526b;
  background: #f7f9fc;
}

.pipeline {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(136px, 1fr));
  gap: 10px;
  margin: 14px 0 20px;
}

.pipeline-step {
  min-height: 92px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 10px;
  padding: 14px;
  text-align: center;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fbfcff;
}

.pipeline-step span {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  margin: 0 auto;
  border-radius: 50%;
  background: #e9eef7;
  font-weight: 800;
}

.pipeline-step.done {
  border-color: #bdebd7;
  background: #f0fbf6;
}

.pipeline-step.done span {
  color: #fff;
  background: var(--green);
}

.pipeline-step.active {
  border-color: #c9d5df;
  background: var(--soft-blue);
}

.result-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 10px;
  margin: 18px 0;
}

.result-list p,
.variables div {
  margin: 0;
  padding: 12px;
  border-radius: 6px;
  background: #f7f9fc;
}

.variables {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 10px;
  margin: 14px 0;
}

.model-card {
  position: relative;
}

.score {
  position: absolute;
  top: 16px;
  right: 16px;
  display: grid;
  place-items: center;
  width: 74px;
  height: 74px;
  border-radius: 50%;
  background: #f3f6f9;
  border: 1px solid #d9e1ea;
}

.score span {
  font-size: 21px;
  font-weight: 900;
  color: var(--primary);
}

.score small {
  font-size: 11px;
  color: var(--muted);
}

code {
  display: block;
  margin: 14px 0;
  padding: 12px;
  white-space: normal;
  color: #15315f;
  background: #f7f9fc;
  border: 1px solid #e2e8f0;
  border-radius: 6px;
}

.model-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
}

.model-strip div {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fbfcff;
}

.model-strip span {
  display: block;
  color: var(--primary);
  font-weight: 800;
}

.terminal {
  margin: 12px 0 20px;
  padding: 16px;
  min-height: 244px;
  color: #cbd5e1;
  background: #121827;
  border-radius: 6px;
}

.terminal p {
  margin: 0 0 8px;
  font-family: "SFMono-Regular", Consolas, monospace;
}

.terminal .done {
  color: #7ee0b6;
}

.terminal .active {
  color: #fbd38d;
}

.mock-warning {
  margin: 18px 0;
  padding: 12px 14px;
  color: #7a4b00;
  background: #fff7e6;
  border: 1px solid #ffd591;
  border-radius: 6px;
  font-weight: 800;
}

.kpi-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 12px;
  margin: 16px 0;
}

.kpi-row div,
.pass-rate {
  padding: 16px;
  border-radius: 6px;
  background: #f7f9fc;
  border: 1px solid var(--line);
}

.kpi-row span,
.pass-rate span {
  display: block;
  color: var(--primary-dark);
  font-size: clamp(26px, 3vw, 32px);
  font-weight: 900;
}

.kpi-row small,
.pass-rate small {
  color: var(--muted);
}

.finding {
  padding: 12px;
  color: var(--green);
  background: #eefbf5;
  border-radius: 6px;
  font-weight: 800;
}

.pass-rate {
  text-align: center;
}

.pass-rate span {
  font-size: clamp(40px, 5vw, 52px);
}

.diagnostics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 12px;
  margin: 16px 0;
}

.diagnostics div,
.ai-note {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fbfcff;
}

.diagnostics span {
  display: block;
  color: var(--muted);
  margin: 8px 0;
}

.diagnostics b {
  color: var(--primary-dark);
}

.ai-note {
  line-height: 1.7;
}

.ai-note button {
  margin-left: 12px;
}

.chart-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 16px;
}

.chart {
  width: 100%;
  min-height: 280px;
  height: clamp(280px, 30vw, 330px);
}

.chart svg {
  width: 100%;
  height: 100%;
  display: block;
}

.side-finding {
  margin: 0;
  color: var(--green);
  font-weight: 800;
}

.interpret-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}

.interpret-grid span {
  color: var(--primary);
  font-weight: 800;
}

.theory-flow {
  padding: 16px;
  color: var(--primary-dark);
  background: #f4f7fa;
  border-radius: 6px;
  line-height: 1.9;
  font-weight: 800;
}

.context-compare {
  margin-top: 16px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fbfcff;
}

.compare-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 150px minmax(0, 1fr);
  gap: 14px;
  align-items: stretch;
}

.compare-grid > div {
  padding: 16px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 6px;
}

.compare-grid p {
  margin: 8px 0;
}

.bridge {
  display: grid;
  place-items: center;
  text-align: center;
  color: var(--primary-dark);
  font-weight: 900;
  line-height: 2;
  background: #f2f5f8 !important;
}

.large span {
  font-size: clamp(30px, 3.5vw, 38px);
}

.conclusion p {
  margin: 8px 0;
}

.toast {
  display: none;
  margin-top: 8px;
  color: var(--green);
  font-weight: 800;
}

.toast.show {
  display: block;
}

.ai-assistant {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

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

.spark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  color: #fff;
  background: #344054;
  border-radius: 6px;
  font-weight: 900;
}

.assistant-head h3,
.assistant-head p {
  margin: 0;
}

.assistant-bubble,
.answer-card {
  padding: 14px;
  border-radius: 6px;
  background: #f4f7fa;
  line-height: 1.7;
}

.summary-card {
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 6px;
}

.session-context {
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
}

.session-context h4 {
  margin: 0 0 10px;
}

.session-context p {
  margin: 0 0 8px;
  color: var(--muted);
  font-size: 13px;
}

.summary-card h4,
.quick-questions h4 {
  margin: 0 0 10px;
}

.summary-card p {
  margin: 0 0 10px;
  color: var(--muted);
  font-size: 13px;
}

.summary-card b {
  display: block;
  color: var(--text);
}

.quick-questions {
  display: grid;
  gap: 8px;
}

.quick-questions button {
  min-height: 34px;
  padding: 0 10px;
  text-align: left;
  color: #36445a;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 6px;
}

.quick-questions button.selected {
  color: var(--primary-dark);
  border-color: var(--primary);
  background: #f3f6f9;
}

.answer-card.muted {
  color: var(--muted);
  background: #f7f9fc;
}

@media (max-width: 1360px) {
  .workspace {
    grid-template-columns: 206px minmax(0, 1fr) 270px;
  }

  .topbar {
    padding-inline: 18px;
  }
}

@media (max-width: 1200px) {
  .workspace {
    grid-template-columns: 196px minmax(0, 1fr);
    grid-template-areas:
      "nav main"
      "assistant main";
    height: auto;
    min-height: calc(100vh - 104px);
  }

  .step-nav {
    grid-area: nav;
  }

  .main-panel {
    grid-area: main;
  }

  .ai-assistant {
    grid-area: assistant;
    max-height: none;
  }

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

  .score {
    position: static;
    margin: 0 0 12px auto;
  }

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

  .bridge {
    min-height: 86px;
  }
}

@media (max-width: 980px) {
  .topbar {
    display: block;
    height: auto;
  }

  .session-panel {
    width: 100%;
    margin-top: 12px;
  }

  .breadcrumb {
    flex-wrap: wrap;
  }

  .workspace {
    display: block;
    height: auto;
    padding: 10px;
  }

  .step-nav,
  .main-panel,
  .ai-assistant {
    margin-bottom: 10px;
  }

  .step-nav {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 6px;
  }

  .nav-title {
    grid-column: 1 / -1;
  }

  .step-item {
    margin: 0;
  }

  .dataset-card,
  .step-footer {
    flex-direction: column;
    align-items: stretch;
  }

  .dataset-meta {
    min-width: 0;
    align-items: flex-start;
  }

  .modal-grid,
  .chart-grid {
    grid-template-columns: 1fr;
  }

  .chart {
    min-height: 240px;
  }

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

@media (max-width: 640px) {
  .step-nav {
    grid-template-columns: 1fr;
  }

  .step-page {
    padding: 14px;
  }

  .step-footer {
    position: static;
    margin: 22px -14px -14px;
    padding: 12px 14px;
  }

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

  .kpi-row,
  .result-list,
  .variables,
  .diagnostics,
  .interpret-grid {
    grid-template-columns: 1fr;
  }
}