/* ============================================================
   钢板超声检验笔记 · Plate UT Notes
   风格：杂志编辑风 / 主色 #D83A2E / 背景 #F5F3F3
   ============================================================ */

:root {
  --red: #D83A2E;
  --red-deep: #A32A20;
  --red-tint: #FBEAE7;
  --ink: #1F2229;
  --ink-soft: #3A3E47;
  --muted: #75706B;
  --bg: #F5F3F3;
  --card: #FFFFFF;
  --line: #E7E2DE;
  --line-strong: #D8D2CC;
  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", SimSun, serif;
  --sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Courier New", monospace;
  --w: 1120px;
  --col: 720px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.9;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

/* ---------- 顶栏 ---------- */
.site-header {
  background: var(--card);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 50;
}
.site-header .bar {
  max-width: var(--w);
  margin: 0 auto;
  padding: 0 24px;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
  text-decoration: none;
}
.brand .zh {
  font-family: var(--serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: 2px;
}
.brand .en {
  font-size: 11px;
  letter-spacing: 2.5px;
  text-transform: uppercase;
  color: var(--red);
}
.nav-toggle { display: none; }
.nav-toggle-label {
  display: none;
  width: 40px; height: 40px;
  cursor: pointer;
  align-items: center; justify-content: center;
}
.nav-toggle-label span,
.nav-toggle-label span::before,
.nav-toggle-label span::after {
  display: block;
  width: 22px; height: 2px;
  background: var(--ink);
  position: relative;
  transition: .2s;
}
.nav-toggle-label span::before,
.nav-toggle-label span::after {
  content: "";
  position: absolute; left: 0;
}
.nav-toggle-label span::before { top: -7px; }
.nav-toggle-label span::after { top: 7px; }

.main-nav ul {
  list-style: none;
  display: flex;
  gap: 6px;
}
.main-nav a {
  display: block;
  padding: 8px 14px;
  text-decoration: none;
  font-size: 15px;
  color: var(--ink-soft);
  border-radius: 4px;
  letter-spacing: .5px;
  transition: color .15s, background .15s;
}
.main-nav a:hover { color: var(--red); }
.main-nav a[aria-current="page"] {
  color: var(--red);
  font-weight: 600;
  background: var(--red-tint);
}

@media (max-width: 900px) {
  .nav-toggle-label { display: flex; }
  .main-nav {
    position: absolute;
    top: 68px; left: 0; right: 0;
    background: var(--card);
    border-bottom: 1px solid var(--line);
    display: none;
  }
  .nav-toggle:checked ~ .main-nav { display: block; }
  .main-nav ul { flex-direction: column; padding: 12px 24px 20px; gap: 2px; }
  .main-nav a { padding: 12px 10px; border-bottom: 1px solid var(--line); border-radius: 0; }
}

/* ---------- 面包屑 ---------- */
.crumbs {
  max-width: var(--w);
  margin: 0 auto;
  padding: 18px 24px 0;
  font-size: 13px;
  color: var(--muted);
}
.crumbs a { color: var(--muted); text-decoration: none; }
.crumbs a:hover { color: var(--red); }
.crumbs .sep { margin: 0 8px; color: var(--line-strong); }

/* ---------- 页头（Hero） ---------- */
.hero {
  max-width: var(--w);
  margin: 0 auto;
  padding: 56px 24px 0;
}
.kicker {
  font-size: 13px;
  letter-spacing: 4px;
  text-transform: uppercase;
  color: var(--red);
  font-weight: 600;
}
.hero h1 {
  font-family: var(--serif);
  font-size: clamp(30px, 5.4vw, 52px);
  line-height: 1.32;
  font-weight: 700;
  margin: 14px 0 10px;
  letter-spacing: 1px;
  max-width: 20em;
}
.hero .sub {
  font-size: 16px;
  color: var(--muted);
  max-width: 40em;
}
.hero .wave {
  display: block;
  width: 100%;
  height: 44px;
  margin-top: 34px;
}
.chap-no {
  font-family: var(--serif);
  font-size: clamp(64px, 10vw, 120px);
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1.5px var(--red);
  opacity: .55;
  float: right;
  margin: -8px 0 0 24px;
}
@media (max-width: 640px) {
  .hero { padding-top: 40px; }
  .chap-no { font-size: 64px; }
}

/* ---------- 版心与中文排版 ---------- */
.page {
  max-width: var(--w);
  margin: 0 auto;
  padding: 48px 24px 88px;
}
.article {
  max-width: var(--col);
  margin: 0 auto;
}
.article > p {
  margin: 0 0 26px;
  text-align: justify;
}
.article p.en-note {
  font-size: 14.5px;
  color: var(--muted);
  line-height: 1.8;
}
.article strong { color: var(--red-deep); font-weight: 600; }
.article .en { color: var(--muted); font-size: .85em; letter-spacing: .3px; }

.article h2 {
  font-family: var(--serif);
  font-size: 26px;
  font-weight: 700;
  margin: 64px 0 20px;
  padding-left: 16px;
  border-left: 4px solid var(--red);
  line-height: 1.5;
  clear: both;
}
.article h2 .h-en {
  display: block;
  font-family: var(--sans);
  font-size: 12px;
  font-weight: 400;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--muted);
  margin-top: 4px;
}
.article h3 {
  font-size: 19px;
  font-weight: 600;
  margin: 40px 0 14px;
  color: var(--ink);
}
.article ul, .article ol {
  margin: 0 0 26px;
  padding-left: 1.6em;
}
.article li { margin-bottom: 10px; }

.lead {
  font-size: 19px;
  line-height: 2;
  color: var(--ink-soft);
  margin-bottom: 32px;
}
.lead::first-letter { color: var(--red); font-weight: 700; }

/* ---------- 引文 / 标准原文块 ---------- */
.quote-en {
  background: var(--card);
  border: 1px solid var(--line);
  border-top: 3px solid var(--red);
  padding: 26px 30px;
  margin: 30px 0 34px;
}
.quote-en .lang-tag {
  font-size: 11px;
  letter-spacing: 2px;
  color: var(--red);
  text-transform: uppercase;
  font-weight: 600;
}
.quote-en p {
  font-family: Georgia, "Times New Roman", var(--serif);
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
  font-style: italic;
  margin-top: 8px;
}
.quote-zh {
  border-left: 3px solid var(--line-strong);
  padding: 6px 0 6px 22px;
  margin: 0 0 30px;
  color: var(--ink-soft);
}

/* ---------- 数据速览条 ---------- */
.facts {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin: 44px 0;
}
.facts .fact {
  background: var(--card);
  padding: 22px 20px 18px;
}
.facts .num {
  font-family: var(--serif);
  font-size: 24px;
  font-weight: 700;
  color: var(--red);
  line-height: 1.3;
}
.facts .lab {
  font-size: 13px;
  color: var(--muted);
  margin-top: 6px;
  line-height: 1.6;
}
@media (max-width: 760px) { .facts { grid-template-columns: repeat(2, 1fr); } }

/* ---------- 卡片网格（首页导览） ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
  margin: 40px 0 20px;
}
.card-grid.two { grid-template-columns: repeat(2, 1fr); }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  padding: 30px 28px 26px;
  text-decoration: none;
  color: inherit;
  display: block;
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
  position: relative;
}
.card:hover {
  transform: translateY(-4px);
  border-color: var(--red);
  box-shadow: 0 14px 34px rgba(31, 34, 41, .08);
}
.card .idx {
  font-family: var(--serif);
  font-size: 13px;
  letter-spacing: 2px;
  color: var(--red);
}
.card h3 {
  font-family: var(--serif);
  font-size: 21px;
  font-weight: 700;
  margin: 10px 0 4px;
  color: var(--ink);
}
.card .card-en {
  font-size: 11.5px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--muted);
}
.card p {
  font-size: 14.5px;
  color: var(--muted);
  line-height: 1.8;
  margin-top: 12px;
}
.card .go {
  display: inline-block;
  margin-top: 16px;
  font-size: 13px;
  color: var(--red);
  letter-spacing: 1px;
}
@media (max-width: 900px) { .card-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 620px) {
  .card-grid, .card-grid.two { grid-template-columns: 1fr; }
}

/* ---------- 表格 ---------- */
.tbl-wrap { overflow-x: auto; margin: 28px 0 34px; }
table.tbl {
  width: 100%;
  min-width: 580px;
  border-collapse: collapse;
  background: var(--card);
  font-size: 15px;
}
.tbl th {
  background: var(--ink);
  color: #fff;
  font-weight: 600;
  text-align: left;
  padding: 13px 16px;
  letter-spacing: 1px;
  white-space: nowrap;
}
.tbl td {
  padding: 13px 16px;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
  line-height: 1.75;
}
.tbl tr:nth-child(even) td { background: #FAF8F7; }
.tbl tr:hover td { background: var(--red-tint); }
.tbl .en-cell { color: var(--muted); font-size: 13.5px; }
.tbl .key-cell { font-weight: 600; color: var(--red-deep); white-space: nowrap; }

/* ---------- 提示框 ---------- */
.note {
  background: var(--card);
  border: 1px solid var(--line);
  border-left: 4px solid var(--red);
  padding: 20px 24px;
  margin: 30px 0;
  font-size: 15.5px;
  color: var(--ink-soft);
  line-height: 1.9;
}
.note .note-tag {
  font-weight: 600;
  color: var(--red);
  margin-right: 8px;
}
.note.plain { border-left-color: var(--line-strong); }
.note.plain .note-tag { color: var(--muted); }

/* ---------- 扫查对比图 ---------- */
.scan-figure {
  background: var(--card);
  border: 1px solid var(--line);
  padding: 30px 26px 18px;
  margin: 34px 0;
}
.scan-figure .cap {
  text-align: center;
  font-size: 13.5px;
  color: var(--muted);
  margin-top: 18px;
  line-height: 1.7;
}
.scan-figure .cap b { color: var(--ink-soft); }

/* ---------- 关键词（页面底部） ---------- */
.kw-block {
  max-width: var(--col);
  margin: 72px auto 0;
  padding-top: 26px;
  border-top: 1px solid var(--line);
}
.kw-block .kw-title {
  font-size: 13px;
  letter-spacing: 3px;
  color: var(--muted);
  text-transform: uppercase;
  margin-bottom: 14px;
}
.kw-list { list-style: none; display: flex; flex-wrap: wrap; gap: 10px; }
.kw-list a {
  display: inline-block;
  padding: 7px 16px;
  background: var(--card);
  border: 1px solid var(--line-strong);
  font-size: 14px;
  color: var(--ink-soft);
  text-decoration: none;
  border-radius: 999px;
  transition: all .15s;
}
.kw-list a:hover {
  background: var(--red);
  border-color: var(--red);
  color: #fff;
}
.kw-list a .kw-en {
  display: block;
  font-size: 10.5px;
  color: var(--muted);
  letter-spacing: 1px;
}
.kw-list a:hover .kw-en { color: rgba(255,255,255,.75); }

/* ---------- 上下页 ---------- */
.pager {
  max-width: var(--col);
  margin: 34px auto 0;
  display: flex;
  justify-content: space-between;
  gap: 16px;
}
.pager a {
  flex: 1;
  background: var(--card);
  border: 1px solid var(--line);
  padding: 18px 20px;
  text-decoration: none;
  color: var(--ink-soft);
  font-size: 14.5px;
  line-height: 1.7;
  transition: border-color .15s;
}
.pager a:hover { border-color: var(--red); }
.pager .dir {
  display: block;
  font-size: 11.5px;
  letter-spacing: 2px;
  color: var(--red);
  margin-bottom: 4px;
}
.pager .next { text-align: right; }

/* ---------- 页脚 ---------- */
.site-footer {
  background: var(--ink);
  color: #B9B4AE;
  margin-top: 90px;
}
.site-footer .inner {
  max-width: var(--w);
  margin: 0 auto;
  padding: 56px 24px 40px;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 48px;
}
.site-footer .brand .zh { color: #F0EDE9; }
.site-footer .desc {
  font-size: 13.5px;
  line-height: 1.9;
  margin-top: 14px;
  color: #8E8983;
}
.site-footer h4 {
  font-size: 13px;
  letter-spacing: 3px;
  color: #F0EDE9;
  font-weight: 600;
  margin-bottom: 16px;
}
.site-footer ul { list-style: none; }
.site-footer li { margin-bottom: 10px; }
.site-footer a {
  color: #B9B4AE;
  text-decoration: none;
  font-size: 14px;
}
.site-footer a:hover { color: var(--red); }
.site-footer .legal {
  border-top: 1px solid #34383F;
  max-width: var(--w);
  margin: 0 auto;
  padding: 20px 24px 30px;
  font-size: 12.5px;
  color: #8E8983;
  line-height: 1.9;
}
@media (max-width: 760px) {
  .site-footer .inner { grid-template-columns: 1fr; gap: 36px; }
}

/* ---------- 首页特有 ---------- */
.home-hero {
  padding: 88px 24px 0;
  text-align: left;
}
.home-hero .wave-full {
  display: block;
  width: 100%;
  max-width: var(--w);
  margin: 44px auto 0;
}
.home-grid {
  max-width: var(--w);
  margin: 0 auto;
  padding: 64px 24px 88px;
}
.section-title {
  display: flex;
  align-items: baseline;
  gap: 16px;
  margin-bottom: 30px;
}
.section-title .no {
  font-family: var(--serif);
  font-size: 15px;
  color: var(--red);
  letter-spacing: 2px;
}
.section-title h2 {
  font-family: var(--serif);
  font-size: 30px;
  font-weight: 700;
}
.section-title .line {
  flex: 1;
  height: 1px;
  background: var(--line-strong);
}
.duo {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 56px;
  align-items: start;
}
@media (max-width: 860px) { .duo { grid-template-columns: 1fr; gap: 30px; } }

.stat-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line-strong);
  border: 1px solid var(--line-strong);
}
@media (max-width: 700px) { .stat-strip { grid-template-columns: 1fr 1fr; } }

.big-quote {
  font-family: var(--serif);
  font-size: 21px;
  line-height: 2;
  color: var(--ink);
  padding-left: 22px;
  border-left: 4px solid var(--red);
  margin: 40px 0;
}

/* 动效 */
@keyframes riseIn {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: none; }
}
.hero h1, .hero .sub, .hero .kicker {
  animation: riseIn .55s ease both;
}
.hero .sub { animation-delay: .08s; }
.hero .kicker { animation-delay: 0s; }
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
}