:root {
  --ink: #172026;
  --muted: #66737f;
  --line: #d9e1e7;
  --paper: #f7f5ef;
  --surface: #ffffff;
  --teal: #0f766e;
  --teal-strong: #115e59;
  --amber: #b7791f;
  --red: #b42318;
  --blue: #235789;
  --green-soft: #e7f5ef;
  --amber-soft: #fff4db;
  --red-soft: #ffe8e6;
  --blue-soft: #e8f1fb;
  --shadow: 0 18px 50px rgba(23, 32, 38, 0.09);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: linear-gradient(180deg, #fbfaf6 0%, #eef5f3 100%);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "Microsoft YaHei", sans-serif;
}

button,
input {
  font: inherit;
}

button {
  cursor: pointer;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px clamp(18px, 4vw, 48px);
  border-bottom: 1px solid rgba(217, 225, 231, 0.76);
  background: rgba(251, 250, 246, 0.88);
  backdrop-filter: blur(14px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 240px;
  color: inherit;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border-radius: 8px;
  color: #fff;
  background: var(--teal);
  font-weight: 800;
}

.brand strong,
.brand span {
  display: block;
}

.brand span {
  margin-top: 2px;
  color: var(--muted);
  font-size: 13px;
}

.top-actions {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.top-actions a {
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
}

.top-actions a:hover {
  color: var(--ink);
}

main {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
}

.tool-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.04fr) minmax(360px, 0.82fr);
  gap: clamp(24px, 5vw, 72px);
  align-items: center;
  min-height: calc(100vh - 74px);
  padding: 42px 0 56px;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--teal-strong);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

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

h1 {
  max-width: 760px;
  margin-bottom: 18px;
  font-size: clamp(40px, 7vw, 74px);
  line-height: 1.02;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 12px;
  font-size: 30px;
  line-height: 1.15;
  letter-spacing: 0;
}

h3 {
  font-size: 18px;
  line-height: 1.35;
  letter-spacing: 0;
}

.lead {
  max-width: 680px;
  color: #40505c;
  font-size: 18px;
  line-height: 1.8;
}

.metric-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 34px;
  max-width: 620px;
}

.metric-strip div {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
  background: rgba(255, 255, 255, 0.74);
}

.metric-strip strong {
  display: block;
  font-size: 28px;
}

.metric-strip span {
  color: var(--muted);
  font-size: 14px;
}

.upload-panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.dropzone {
  position: relative;
  display: grid;
  min-height: 340px;
  place-items: center;
  align-content: center;
  gap: 12px;
  padding: 34px;
  border: 2px dashed #aac6c1;
  border-radius: 8px;
  background:
    linear-gradient(135deg, rgba(15, 118, 110, 0.08), rgba(35, 87, 137, 0.06)),
    var(--paper);
  text-align: center;
  transition:
    border-color 160ms ease,
    transform 160ms ease,
    background 160ms ease;
}

.dropzone.dragover {
  border-color: var(--teal);
  background:
    linear-gradient(135deg, rgba(15, 118, 110, 0.16), rgba(35, 87, 137, 0.1)),
    var(--paper);
  transform: translateY(-2px);
}

.dropzone input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.upload-icon {
  display: grid;
  width: 54px;
  height: 54px;
  place-items: center;
  border-radius: 8px;
  color: #fff;
  background: var(--blue);
  font-size: 34px;
  line-height: 1;
}

.dropzone h2 {
  margin-bottom: 0;
}

.dropzone p {
  margin-bottom: 8px;
  color: var(--muted);
}

.sample-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: 14px;
}

.primary-button,
.secondary-button,
.ghost-button,
.icon-button {
  border: 1px solid transparent;
  border-radius: 8px;
  min-height: 42px;
  padding: 0 16px;
  font-weight: 700;
}

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

.primary-button:hover {
  background: var(--teal-strong);
}

.secondary-button {
  border-color: var(--line);
  color: var(--ink);
  background: #fff;
}

.secondary-button:hover,
.ghost-button:hover,
.icon-button:hover {
  border-color: #9eb2bf;
}

.ghost-button {
  border-color: var(--line);
  color: var(--teal-strong);
  background: transparent;
}

.icon-button {
  width: 42px;
  padding: 0;
  color: var(--muted);
  background: #fff;
  font-size: 24px;
}

.results,
.content-band {
  margin-bottom: 26px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: clamp(18px, 3vw, 28px);
  background: rgba(255, 255, 255, 0.86);
}

.hidden {
  display: none;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 20px;
}

.section-heading h2 {
  margin-bottom: 0;
}

.summary-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
  margin-bottom: 20px;
}

.summary-card {
  min-height: 112px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 16px;
  background: #fff;
}

.summary-card span {
  color: var(--muted);
  font-size: 13px;
}

.summary-card strong {
  display: block;
  margin-top: 10px;
  font-size: 34px;
  line-height: 1;
}

.summary-card small {
  display: block;
  margin-top: 10px;
  color: var(--muted);
}

.toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}

.segmented {
  display: flex;
  gap: 6px;
  padding: 5px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f5f8f7;
}

.tab-button {
  border: 0;
  border-radius: 6px;
  min-height: 36px;
  padding: 0 14px;
  color: var(--muted);
  background: transparent;
  font-weight: 700;
}

.tab-button.active {
  color: #fff;
  background: var(--teal);
}

.export-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.error-list {
  display: grid;
  gap: 14px;
}

.error-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  background: #fff;
}

.error-card-header {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 14px;
  padding: 18px;
  border-bottom: 1px solid var(--line);
  background: #fbfcfc;
}

.error-card-header h3 {
  margin-bottom: 5px;
}

.error-card-header p {
  margin-bottom: 0;
  color: var(--muted);
  line-height: 1.6;
}

.severity {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  border-radius: 999px;
  padding: 0 10px;
  font-size: 12px;
  font-weight: 800;
  white-space: nowrap;
}

.severity.high {
  color: var(--red);
  background: var(--red-soft);
}

.severity.medium {
  color: var(--amber);
  background: var(--amber-soft);
}

.severity.low {
  color: var(--blue);
  background: var(--blue-soft);
}

.error-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.72fr);
  gap: 18px;
  padding: 18px;
}

.fix-list,
.case-box,
.affected-list {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 14px;
  background: #fff;
}

.fix-list h4,
.case-box h4,
.affected-list h4 {
  margin: 0 0 10px;
  font-size: 14px;
}

.fix-list ol {
  margin: 0;
  padding-left: 22px;
  color: #32414c;
  line-height: 1.65;
}

.affected-list {
  display: grid;
  gap: 8px;
  align-content: start;
}

.pill-row {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.pill {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 6px 9px;
  color: #40505c;
  background: #f8faf9;
  font-size: 12px;
}

.case-box textarea {
  width: 100%;
  min-height: 168px;
  resize: vertical;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 12px;
  color: #25323a;
  background: #f8faf9;
  line-height: 1.5;
}

.rule-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.guide-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.guide-grid a,
.primary-link {
  display: flex;
  align-items: center;
  min-height: 54px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 14px 16px;
  color: var(--teal-strong);
  background: #fff;
  font-weight: 800;
  text-decoration: none;
}

.guide-grid a:hover,
.primary-link:hover {
  border-color: #91b7b1;
  background: #f4fbf9;
}

.feedback-band p {
  max-width: 820px;
  color: var(--muted);
  line-height: 1.8;
}

.primary-link {
  display: inline-flex;
  margin-top: 8px;
  color: #fff;
  background: var(--teal);
}

.article-shell {
  width: min(920px, calc(100% - 32px));
  margin: 0 auto;
  padding: 42px 0 70px;
}

.article-hero {
  margin-bottom: 20px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 24px;
}

.article-hero h1 {
  max-width: 880px;
  font-size: clamp(34px, 6vw, 58px);
}

.article-card {
  margin-top: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: clamp(18px, 3vw, 26px);
  background: rgba(255, 255, 255, 0.9);
}

.article-card h2 {
  font-size: 24px;
}

.article-card h3 {
  margin: 0 0 10px;
  font-size: 18px;
}

.article-card p,
.article-card li {
  color: #40505c;
  line-height: 1.8;
}

.article-card code {
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 2px 6px;
  background: #f8faf9;
}

.article-cta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 22px;
}

.article-meta {
  margin: 0 0 18px;
  color: #65727c;
  font-size: 14px;
}

.article-cta a {
  min-height: 44px;
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  justify-content: center;
  margin: 26px 0 46px;
  color: var(--muted);
}

.site-footer a {
  color: var(--muted);
  font-weight: 700;
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--teal-strong);
}

.rule-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 16px;
  background: #fff;
}

.rule-card strong {
  display: block;
  margin-bottom: 7px;
  color: var(--blue);
  font-size: 18px;
}

.rule-card p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.steps {
  display: grid;
  gap: 12px;
  margin: 0;
  padding-left: 22px;
}

.steps li {
  padding-left: 8px;
  line-height: 1.7;
}

.steps strong,
.steps span {
  display: block;
}

.steps span,
.privacy p {
  color: var(--muted);
}

.toast {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 20;
  max-width: 360px;
  transform: translateY(20px);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 12px 14px;
  color: #fff;
  background: rgba(23, 32, 38, 0.94);
  opacity: 0;
  pointer-events: none;
  transition:
    opacity 160ms ease,
    transform 160ms ease;
}

.toast.show {
  transform: translateY(0);
  opacity: 1;
}

@media (max-width: 900px) {
  .topbar,
  .section-heading,
  .toolbar,
  .error-card-header {
    align-items: stretch;
    flex-direction: column;
  }

  .top-actions {
    justify-content: flex-start;
  }

  .tool-hero,
  .error-body {
    grid-template-columns: 1fr;
  }

  .tool-hero {
    min-height: auto;
    padding-top: 30px;
  }

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

@media (max-width: 560px) {
  main {
    width: min(100% - 20px, 1180px);
  }

  h1 {
    font-size: 38px;
  }

  .metric-strip,
  .summary-grid,
  .rule-grid,
  .guide-grid {
    grid-template-columns: 1fr;
  }

  .dropzone {
    min-height: 280px;
    padding: 22px;
  }

  .segmented,
  .export-actions {
    width: 100%;
  }

  .tab-button,
  .export-actions button {
    flex: 1;
  }
}