/* ============================================================
   奥印ERP · 在线教程
   与落地页同一设计语言：宣纸白 / 墨色 / 印章红
   ============================================================ */

:root {
  --paper:     #f6f4ef;
  --paper-2:   #efece4;
  --card:      #fffefb;
  --ink:       #1a1c20;
  --ink-2:     #4a4d53;
  --muted:     #8a8d93;
  --line:      #e3dfd5;
  --seal:      #c03d21;
  --seal-deep: #a53219;
  --seal-soft: rgba(192, 61, 33, .07);
  --dark:      #15171c;
  --dark-line: #2c2f37;

  --font-sans: "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC",
               "Noto Sans SC", "Microsoft YaHei", -apple-system, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "SF Mono", "JetBrains Mono", Consolas, Menlo, monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

::selection { background: var(--seal); color: var(--paper); }

a { color: var(--seal-deep); text-decoration: none; }
.content a:hover { text-decoration: underline; text-underline-offset: 3px; }

/* ---------------- 顶栏 ---------------- */

.topbar {
  height: 66px;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 32px;
  border-bottom: 1px solid var(--line);
  position: sticky; top: 0; z-index: 10;
  background: rgba(246, 244, 239, .88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.brand {
  display: inline-flex; align-items: center; gap: 11px;
  font-size: 18px; font-weight: 800; color: var(--ink);
  letter-spacing: .02em;
}
.brand::before {
  content: "印";
  display: inline-flex; align-items: center; justify-content: center;
  width: 30px; height: 30px; border-radius: 7px;
  background: var(--seal); color: var(--paper);
  font-size: 16px; font-weight: 700;
  box-shadow: 0 2px 8px rgba(192, 61, 33, .28);
}

.topbar nav { display: flex; gap: 26px; }
.topbar nav a {
  color: var(--ink-2); font-weight: 600; font-size: 14px;
  position: relative; padding: 4px 0;
  transition: color .2s;
}
.topbar nav a::after {
  content: ""; position: absolute; left: 0; right: 100%; bottom: -2px;
  height: 2px; background: var(--seal);
  transition: right .25s ease;
}
.topbar nav a:hover { color: var(--ink); }
.topbar nav a:hover::after { right: 0; }

/* ---------------- 布局 ---------------- */

.layout {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr) 260px;
  gap: 40px;
  max-width: 1540px;
  margin: 0 auto;
  padding: 40px 32px;
}

.sidebar, .toc {
  position: sticky; top: 92px; align-self: start;
  max-height: calc(100vh - 120px); overflow: auto;
}

.side-title, .toc-title {
  font-family: var(--font-mono);
  font-size: 11px; font-weight: 700;
  letter-spacing: .22em; text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 14px;
  padding-left: 2px;
}
.side-title::before, .toc-title::before {
  content: ""; display: inline-block;
  width: 18px; height: 2px; background: var(--seal);
  margin-right: 9px; vertical-align: 3px;
}

/* ---- 左侧教程列表 ---- */

.sidebar a {
  display: block;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 10px;
  margin-bottom: 10px;
  color: var(--ink);
  background: var(--card);
  font-weight: 600; font-size: 15px;
  transition: border-color .2s, transform .2s, box-shadow .2s;
}
.sidebar a:hover {
  border-color: rgba(192, 61, 33, .45);
  transform: translateY(-1px);
  box-shadow: 0 10px 24px -16px rgba(26, 28, 32, .25);
}
.sidebar a.active {
  border-color: var(--seal);
  background: var(--seal-soft);
  box-shadow: inset 3px 0 0 var(--seal);
}
.sidebar span {
  display: block;
  color: var(--muted);
  font-size: 12.5px; font-weight: 400;
  line-height: 1.6; margin-top: 5px;
}

/* ---- 右侧目录 ---- */

.toc a {
  display: block;
  color: var(--ink-2); font-size: 13.5px;
  padding: 5px 0 5px 12px;
  border-left: 2px solid var(--line);
  transition: color .15s, border-color .15s;
}
.toc a:hover { border-left-color: var(--seal); color: var(--seal-deep); }
.toc .level-3 { padding-left: 26px; color: var(--muted); }

/* ---------------- 正文 ---------------- */

.content { min-width: 0; max-width: 920px; }

.hero {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 34px 38px;
  margin-bottom: 36px;
  overflow: hidden;
}
.hero::after {
  content: "印";
  position: absolute; right: -14px; bottom: -38px;
  font-size: 150px; font-weight: 800; line-height: 1;
  color: var(--seal); opacity: .055;
  transform: rotate(8deg);
  pointer-events: none;
}
.hero p {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px; font-weight: 700;
  letter-spacing: .2em;
  color: var(--seal);
}
.hero h1 {
  margin: 0;
  font-size: 36px; line-height: 1.3; letter-spacing: .01em;
  color: var(--ink);
}
.hero span { display: block; margin-top: 10px; color: var(--ink-2); font-size: 15px; }

h1, h2, h3, h4 { line-height: 1.4; color: var(--ink); letter-spacing: .01em; }
.content > h1 { font-size: 30px; margin-top: 8px; }

h2 {
  font-size: 24px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 10px;
  margin-top: 56px;
  position: relative;
}
h2::after {
  content: ""; position: absolute; left: 0; bottom: -1px;
  width: 44px; height: 2px; background: var(--seal);
}
h3 { font-size: 19px; margin-top: 34px; }

p, li { font-size: 15.5px; color: var(--ink-2); }
li { margin-bottom: 2px; }
strong { color: var(--ink); }
ul, ol { padding-left: 24px; }

blockquote {
  margin: 18px 0;
  padding: 12px 20px;
  border-left: 3px solid var(--seal);
  background: var(--seal-soft);
  border-radius: 0 10px 10px 0;
  color: var(--ink-2);
}

/* ---- 代码 ---- */

code {
  background: var(--paper-2);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 1px 7px;
  font-family: var(--font-mono);
  font-size: .9em;
  color: var(--seal-deep);
}

pre {
  background: var(--dark);
  border: 1px solid var(--dark-line);
  color: #c8ccd4;
  border-radius: 12px;
  padding: 20px 22px;
  overflow: auto;
  line-height: 1.8;
  box-shadow: 0 18px 44px -24px rgba(0, 0, 0, .45);
}
pre code {
  background: transparent; border: 0; padding: 0;
  color: inherit; font-size: 13.5px;
}

/* ---- 表格 ---- */

table {
  width: 100%;
  border-collapse: separate; border-spacing: 0;
  margin: 22px 0;
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
  font-size: 14.5px;
  background: var(--card);
}
th, td {
  border-bottom: 1px solid var(--line);
  border-right: 1px solid var(--line);
  padding: 11px 14px;
  vertical-align: top;
}
th:last-child, td:last-child { border-right: 0; }
tr:last-child td { border-bottom: 0; }
th {
  background: var(--paper-2);
  text-align: left;
  font-size: 13px; letter-spacing: .05em;
  color: var(--ink);
}

/* ---- 图片 ---- */

img {
  max-width: 100%;
  border: 1px solid var(--line);
  border-radius: 12px;
  margin: 14px 0;
  box-shadow: 0 16px 40px -24px rgba(26, 28, 32, .25);
}

hr { border: 0; border-top: 1px solid var(--line); margin: 40px 0; }

/* ---------------- 响应式 ---------------- */

@media (max-width: 1100px) {
  .layout { grid-template-columns: 250px minmax(0, 1fr); }
  .toc { display: none; }
}

@media (max-width: 760px) {
  .topbar { padding: 0 18px; }
  .topbar nav { gap: 14px; font-size: 13px; }
  .layout { display: block; padding: 20px 18px; }
  .sidebar { position: static; max-height: none; margin-bottom: 24px; }
  .hero { padding: 24px 22px; }
  .hero h1 { font-size: 27px; }
  h2 { font-size: 21px; }
}