*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 15px;
  line-height: 1.7;
  color: #1a1f36;
  max-width: 820px;
  margin: 0 auto;
  padding: 40px 32px 80px;
}

h1 {
  font-size: 28px;
  font-weight: 700;
  color: #1a1f36;
  margin-bottom: 6px;
}
h2 {
  font-size: 18px;
  font-weight: 600;
  color: #1a1f36;
  margin: 40px 0 12px;
  padding-bottom: 8px;
  border-bottom: 2px solid #e8eaf0;
}
h3 {
  font-size: 15px;
  font-weight: 600;
  color: #1a1f36;
  margin: 24px 0 8px;
}
p {
  margin-bottom: 12px;
  color: #3d4461;
}
a {
  color: #3b7dd8;
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}
strong {
  font-weight: 600;
  color: #1a1f36;
}
code {
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 13px;
  background: #f0f2f8;
  color: #5b3ec8;
  padding: 2px 6px;
  border-radius: 4px;
}

.intro-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}
.badge {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 3px 9px;
  border-radius: 20px;
}
.badge-blue {
  background: #ddeeff;
  color: #1a5fa8;
}
.badge-green {
  background: #dcf5e7;
  color: #166534;
}
.badge-amber {
  background: #fef3c7;
  color: #92400e;
}
.intro-text {
  font-size: 16px;
  color: #3d4461;
  margin-bottom: 28px;
  padding-bottom: 24px;
  border-bottom: 1px solid #e8eaf0;
}

.steps-nav {
  display: flex;
  gap: 0;
  margin: 28px 0 36px;
  border: 1px solid #e0e4ef;
  border-radius: 10px;
  overflow: hidden;
  font-size: 12px;
}
.steps-nav a {
  flex: 1;
  text-align: center;
  padding: 10px 6px;
  color: #6b7280;
  background: #f7f8fc;
  border-right: 1px solid #e0e4ef;
  text-decoration: none;
  line-height: 1.3;
  transition: background 0.15s;
}
.steps-nav a:last-child {
  border-right: none;
}
.steps-nav a:hover {
  background: #eef1fb;
  color: #1a1f36;
}
.steps-nav a .step-num {
  display: block;
  font-size: 16px;
  font-weight: 700;
  color: #3b7dd8;
  margin-bottom: 2px;
}

.step {
  margin-bottom: 40px;
  padding: 24px 28px;
  border: 1px solid #e0e4ef;
  border-radius: 12px;
  background: #fff;
}
.step-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
}
.step-number {
  width: 36px;
  height: 36px;
  min-width: 36px;
  border-radius: 50%;
  background: #3b7dd8;
  color: #fff;
  font-size: 16px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}
.step-title {
  font-size: 17px;
  font-weight: 700;
  color: #1a1f36;
}

ol,
ul {
  padding-left: 22px;
  margin-bottom: 14px;
  color: #3d4461;
}
ol {
  list-style: decimal;
}
ul {
  list-style: disc;
}
li {
  margin-bottom: 6px;
  padding-left: 4px;
}
li::marker {
  color: #3b7dd8;
  font-weight: 600;
}

ol ul {
  margin-top: 8px;
  margin-bottom: 8px;
  list-style: circle;
}

.callout {
  display: flex;
  gap: 12px;
  padding: 14px 16px;
  border-radius: 8px;
  margin: 16px 0;
  font-size: 14px;
  line-height: 1.6;
}
.callout-icon {
  font-size: 16px;
  flex-shrink: 0;
  margin-top: 1px;
}
.callout-tip {
  background: #fefce8;
  border-left: 4px solid #f59e0b;
  color: #78350f;
}
.callout-info {
  background: #eff6ff;
  border-left: 4px solid #3b82f6;
  color: #1e3a5f;
}
.callout-warn {
  background: #fff7ed;
  border-left: 4px solid #f97316;
  color: #7c2d12;
}
.callout p {
  margin: 0;
  color: inherit;
}
.callout strong {
  color: inherit;
}

.table-wrap {
  overflow-x: auto;
  margin: 16px 0;
  border-radius: 8px;
  border: 1px solid #e0e4ef;
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}
thead tr {
  background: #3b7dd8;
  color: #fff;
}
thead th {
  padding: 10px 14px;
  text-align: left;
  font-weight: 600;
  font-size: 13px;
}
tbody tr {
  border-bottom: 1px solid #e8eaf0;
}
tbody tr:last-child {
  border-bottom: none;
}
tbody tr:nth-child(even) {
  background: #f7f8fc;
}
tbody td {
  padding: 9px 14px;
  color: #3d4461;
  vertical-align: top;
}
tbody td:first-child {
  font-weight: 600;
  color: #1a1f36;
  white-space: nowrap;
}

.quick-ref {
  background: #f7f8fc;
  border-radius: 12px;
  padding: 24px 28px;
  margin-top: 48px;
  border: 1px solid #e0e4ef;
}
.quick-ref h2 {
  margin-top: 0;
  border-bottom-color: #c7d2e8;
}
.quick-ref tbody td:first-child {
  color: #3b7dd8;
}
.quick-ref tbody tr:nth-child(even) {
  background: #eef1fb;
}
.quick-ref tbody tr:nth-child(odd) {
  background: #f7f8fc;
}

.ui {
  display: inline-block;
  background: #eef1fb;
  color: #1e3a72;
  font-size: 12px;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 5px;
  border: 1px solid #c7d2e8;
  white-space: nowrap;
}

.section-divider {
  border: none;
  border-top: 1px solid #e8eaf0;
  margin: 36px 0;
}

.panel {
  border: 1px solid #e0e4ef;
  border-radius: 8px;
  overflow: hidden;
  margin: 16px 0;
}
.panel-header {
  background: #f0f4fb;
  padding: 10px 16px;
  font-size: 14px;
  font-weight: 600;
  color: #1e3a72;
  border-bottom: 1px solid #e0e4ef;
}
.panel-body {
  padding: 14px 16px;
}

.toc {
  background: #f7f8fc;
  border: 1px solid #e0e4ef;
  border-radius: 8px;
  padding: 16px 20px;
  margin-bottom: 32px;
  font-size: 14px;
}
.toc-title {
  font-weight: 600;
  color: #1a1f36;
  margin-bottom: 8px;
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.toc ol {
  margin: 0;
  padding-left: 18px;
}
.toc li {
  margin-bottom: 4px;
}
.toc a {
  color: #3b7dd8;
}

@media (max-width: 600px) {
  body {
    padding: 24px 16px 60px;
  }
  .steps-nav {
    flex-direction: column;
  }
  .steps-nav a {
    border-right: none;
    border-bottom: 1px solid #e0e4ef;
  }
  .steps-nav a:last-child {
    border-bottom: none;
  }
  .step {
    padding: 18px 16px;
  }
}