:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --surface-alt: #eef4ff;
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --accent: #10b981;
  --text: #111827;
  --muted: #6b7280;
  --border: #dfe7f5;
  --danger: #dc2626;
  --warning: #f59e0b;
  --success: #059669;
  --shadow: 0 16px 40px rgba(37, 99, 235, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Segoe UI", "Microsoft YaHei", Arial, sans-serif;
  color: var(--text);
  background: linear-gradient(180deg, #f3f7ff 0%, #f8fafc 170px, var(--bg) 100%);
  line-height: 1.7;
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

img {
  max-width: 100%;
}

.container {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(14px);
  background: rgba(255, 255, 255, 0.82);
  border-bottom: 1px solid rgba(223, 231, 245, 0.9);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
}

.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--primary), #60a5fa);
  color: #fff;
  font-size: 0.95rem;
  box-shadow: var(--shadow);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 18px;
  color: var(--muted);
  flex-wrap: wrap;
}

.nav-links a {
  color: var(--muted);
  font-size: 0.96rem;
}

.hero {
  padding: 72px 0 30px;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 32px;
  align-items: center;
}

.eyebrow {
  display: inline-block;
  margin: 0 0 18px;
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(37, 99, 235, 0.08);
  color: var(--primary);
  font-weight: 700;
  font-size: 0.8rem;
}

h1, h2, h3 {
  line-height: 1.25;
  margin: 0 0 18px;
}

h1 {
  font-size: clamp(2.1rem, 4vw, 4rem);
  letter-spacing: -0.04em;
}

.lead {
  color: var(--muted);
  font-size: 1.06rem;
  max-width: 660px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 24px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 18px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover {
  text-decoration: none;
  transform: translateY(-1px);
  box-shadow: 0 12px 30px rgba(17, 24, 39, 0.08);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), #3b82f6);
  border-color: transparent;
  color: #fff;
}

.btn-success {
  background: linear-gradient(135deg, var(--accent), #34d399);
  border-color: transparent;
  color: #fff;
}

.hero-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 24px;
  box-shadow: var(--shadow);
  padding: 24px;
}

.kpi-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 20px;
}

.kpi-card {
  padding: 18px 16px;
  border-radius: 18px;
  background: var(--surface-alt);
  border: 1px solid var(--border);
}

.kpi-card strong {
  display: block;
  font-size: 1.75rem;
  margin-bottom: 8px;
}

.section {
  padding: 28px 0 10px;
}

.section-header {
  margin-bottom: 22px;
}

.section-header h2 {
  font-size: clamp(1.75rem, 2.7vw, 2.5rem);
}

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

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 22px 18px;
  box-shadow: 0 10px 26px rgba(15, 23, 42, 0.04);
}

.card h3 {
  margin: 0 0 12px;
  font-size: 1.2rem;
}

.card p {
  margin: 0 0 14px;
  color: var(--muted);
}

.badge {
  display: inline-block;
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(16, 185, 129, 0.12);
  color: var(--success);
  font-size: 0.75rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.feature-list,
.article-list,
.side-list,
.faq-list,
.inline-list {
  display: grid;
  gap: 10px;
  padding: 0;
  list-style: none;
}

.feature-list li,
.article-list li,
.side-list li,
.inline-list li {
  position: relative;
  padding-left: 22px;
  color: var(--muted);
}

.feature-list li::before,
.article-list li::before,
.side-list li::before,
.inline-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--success);
  font-weight: 700;
}

.two-col {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 28px;
  align-items: start;
}

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 22px;
  padding: 24px 20px;
  box-shadow: 0 10px 30px rgba(15, 23, 42, 0.04);
}

.faq-list details {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 14px 16px;
}

.faq-list details + details {
  margin-top: 12px;
}

.faq-list summary {
  cursor: pointer;
  font-weight: 600;
}

.faq-list p {
  margin: 12px 0 0;
  color: var(--muted);
}

.page-head {
  padding: 52px 0 18px;
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
  font-size: 0.82rem;
  color: var(--muted);
}

.breadcrumbs a {
  color: var(--primary);
  text-decoration: none;
}

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

.info-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.info-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  box-shadow: 0 10px 28px rgba(15, 23, 42, 0.04);
  padding: 22px 20px;
}

.info-card h3 {
  margin-top: 0;
  margin-bottom: 12px;
}

.info-card ul {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
}

.info-card li + li {
  margin-top: 8px;
}

.tool-layout {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 20px;
}

.tool-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 24px;
  box-shadow: var(--shadow);
  padding: 24px;
}

textarea {
  width: 100%;
  min-height: 250px;
  border-radius: 16px;
  border: 1px solid var(--border);
  padding: 16px 18px;
  background: #f9fbff;
  font: 500 0.98rem/1.6 "Segoe UI", "Microsoft YaHei", sans-serif;
  resize: vertical;
  color: var(--text);
}

textarea:focus {
  outline: 2px solid rgba(37, 99, 235, 0.16);
  border-color: var(--primary);
}

.tool-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 18px 0;
}

.output-box {
  background: #f9fbff;
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 16px 18px;
  min-height: 180px;
  white-space: pre-wrap;
  word-break: break-word;
  font-family: "Consolas", "Microsoft YaHei", monospace;
}

.side-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 22px 20px;
  box-shadow: 0 8px 24px rgba(15, 23, 42, 0.04);
}

.note {
  color: var(--muted);
  font-size: 0.95rem;
}

.article {
  padding: 20px 0 50px;
}

.article-body {
  max-width: 760px;
  margin: 0 auto;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 30px 24px;
  box-shadow: var(--shadow);
}

.article-body h2 {
  margin-top: 28px;
}

.article-body p,
.article-body li {
  color: var(--muted);
}

.article-body code {
  font-family: "Consolas", "Microsoft YaHei", monospace;
  background: #eef3ff;
  border-radius: 8px;
  padding: 2px 6px;
}

.diff-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 18px;
}

.diff-panel {
  border: 1px solid var(--border);
  border-radius: 16px;
  background: #f9fbff;
  overflow: hidden;
}

.diff-panel h4 {
  padding: 12px 16px;
  margin: 0;
  background: #edf3ff;
  border-bottom: 1px solid var(--border);
}

.diff-lines {
  padding: 10px 16px;
  min-height: 220px;
  white-space: pre-wrap;
  font-family: "Consolas", "Microsoft YaHei", monospace;
}

.diff-line {
  display: block;
  border-radius: 8px;
  padding: 3px 6px;
  margin-bottom: 2px;
}

.diff-line.added {
  background: rgba(16, 185, 129, 0.08);
  color: var(--success);
}

.diff-line.removed {
  background: rgba(220, 38, 38, 0.08);
  color: var(--danger);
}

.diff-line.changed {
  background: rgba(245, 158, 11, 0.08);
  color: #9a6700;
}

.lang-switcher {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px;
  border: 1px solid rgba(148, 163, 184, 0.35);
  border-radius: 999px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.92), rgba(241, 245, 249, 0.8));
  box-shadow: 0 8px 20px rgba(15, 23, 42, 0.06);
}

.lang-btn {
  border: 0;
  background: transparent;
  cursor: pointer;
  color: var(--muted);
  border-radius: 999px;
  padding: 8px 12px;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  transition: all 0.2s ease;
}

.lang-btn:hover {
  color: var(--text);
}

.lang-btn.active {
  background: linear-gradient(135deg, var(--primary), #3b82f6);
  color: #fff;
  box-shadow: 0 8px 18px rgba(37, 99, 235, 0.24);
}

.footer {
  padding: 32px 0 60px;
  color: var(--muted);
}

@media (max-width: 900px) {
  .hero-inner,
  .tool-layout,
  .two-col,
  .diff-container,
  .info-grid {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 560px) {
  .nav {
    flex-direction: column;
    align-items: flex-start;
    padding: 12px 0;
  }

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

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

  .tool-actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }
}