/* 衡远钢构 — 结构图纸视觉系统
   字体全部使用系统字体，无外部依赖 */

:root {
  --paper: #f2f0ea;
  --paper-2: #e9e6dd;
  --paper-3: #dedad0;
  --ink: #16191c;
  --ink-2: #39424a;
  --ink-3: #6e7378;
  --steel: #1e272c;
  --red: #a63a2b;
  --line: #c9c5bb;
  --line-2: #a8a49a;
  --cn: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --num: "Bahnschrift", "DIN Alternate", "Inter", "Segoe UI", sans-serif;
  --mono: "Cascadia Mono", "JetBrains Mono", "Consolas", monospace;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--cn);
  font-size: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image: linear-gradient(90deg, rgba(22, 25, 28, 0.04) 1px, transparent 1px);
  background-size: 80px 100%;
}
.page { position: relative; z-index: 1; }
.wrap { max-width: 1560px; margin: 0 auto; padding: 0 clamp(20px, 4.2vw, 72px); }
.mono {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  color: var(--ink-3);
  text-transform: uppercase;
}
.din {
  font-family: var(--num);
  font-stretch: 87.5%;
  font-weight: 500;
  letter-spacing: -0.01em;
  font-variant-numeric: tabular-nums;
}
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }

/* ---------- 图纸条 ---------- */
.sheetbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 34px;
  padding: 0 clamp(20px, 4.2vw, 72px);
  gap: 16px;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  color: var(--ink-3);
  border-bottom: 1px solid var(--line);
  text-transform: uppercase;
}
.sheetbar b { font-weight: 400; color: var(--ink-2); }
.sheetbar i { font-style: normal; }
.sheetbar > span:first-child { white-space: nowrap; overflow: hidden; }

/* ---------- 页头 ---------- */
.hdr {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(242, 240, 234, 0.94);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--ink);
}
.hdr-in { display: flex; align-items: center; height: 76px; gap: 36px; }
.logo { font-size: 19px; font-weight: 500; letter-spacing: 0.04em; line-height: 1.15; }
.logo em {
  display: block;
  font-family: var(--mono);
  font-size: 8.5px;
  font-style: normal;
  letter-spacing: 0.24em;
  color: var(--ink-3);
  margin-top: 4px;
}
.nav { display: flex; gap: 28px; margin-left: auto; }
.nav a { font-size: 13.5px; color: var(--ink-2); position: relative; padding: 5px 0; }
.nav a i {
  font-family: var(--mono);
  font-size: 9px;
  font-style: normal;
  color: var(--ink-3);
  margin-right: 6px;
  vertical-align: super;
  letter-spacing: 0;
}
.nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: var(--ink);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.35s cubic-bezier(0.2, 0.8, 0.2, 1);
}
.nav a:hover { color: var(--ink); }
.nav a:hover::after, .nav a.on::after { transform: scaleX(1); }
.nav a.on { color: var(--ink); }
.menu-btn { display: none; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-size: 13.5px;
  padding: 12px 20px;
  border: 1px solid var(--ink);
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  transition: background 0.25s, color 0.25s, border-color 0.25s;
  font-family: var(--cn);
  white-space: nowrap;
}
.btn:hover { background: var(--ink); color: var(--paper); }
.btn.solid { background: var(--ink); color: var(--paper); }
.btn.solid:hover { background: var(--red); border-color: var(--red); color: #fff; }
.btn .ar { font-family: var(--mono); font-size: 12px; }
.btn.lg { padding: 15px 26px; font-size: 14.5px; }

/* ---------- 首页首屏 ---------- */
.hero { padding: clamp(44px, 6.4vh, 84px) 0 0; }
.hero-grid {
  display: grid;
  grid-template-columns: 1.06fr 0.94fr;
  gap: clamp(24px, 3.4vw, 56px);
  align-items: end;
}
.eyebrow { display: flex; align-items: center; gap: 12px; margin-bottom: clamp(24px, 3.4vh, 40px); }
.eyebrow span { font-family: var(--mono); font-size: 10px; letter-spacing: 0.2em; color: var(--ink-3); text-transform: uppercase; }
.eyebrow .bar { width: 44px; height: 1px; background: var(--line-2); }
h1 { font-size: clamp(40px, 4.9vw, 74px); line-height: 1.14; font-weight: 500; letter-spacing: -0.025em; }
h1 .n { font-family: var(--num); font-stretch: 87.5%; font-weight: 500; letter-spacing: -0.02em; }
h1 .u { position: relative; display: inline-block; }
h1 .u::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0.06em;
  height: 3px;
  background: var(--red);
  opacity: 0.85;
}
.hero .lede {
  margin-top: clamp(24px, 3vh, 34px);
  max-width: 48ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-2);
}
.hero-actions { display: flex; gap: 12px; margin-top: clamp(26px, 3.4vh, 38px); flex-wrap: wrap; }

/* ---------- 图框 ---------- */
.plate { position: relative; border: 1px solid var(--line-2); background: var(--paper-2); overflow: hidden; }
.plate svg { width: 100%; height: 100%; display: block; }
.plate .tag {
  position: absolute;
  left: 0;
  bottom: 0;
  background: var(--paper);
  border-top: 1px solid var(--line-2);
  border-right: 1px solid var(--line-2);
  padding: 6px 12px;
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  text-transform: uppercase;
}
.plate .tag.right { left: auto; right: 0; border-right: 0; border-left: 1px solid var(--line-2); }
.plate .corner { position: absolute; width: 9px; height: 9px; border: 1px solid var(--ink); opacity: 0.5; }
.plate .c1 { top: 10px; left: 10px; border-right: 0; border-bottom: 0; }
.plate .c2 { top: 10px; right: 10px; border-left: 0; border-bottom: 0; }
.plate .c3 { bottom: 10px; right: 10px; border-left: 0; border-top: 0; }
.plate .c4 { bottom: 10px; left: 10px; border-right: 0; border-top: 0; }
.hero-plate { height: clamp(280px, 42vh, 430px); display: flex; align-items: center; justify-content: center; }

/* ---------- 尺寸标注线 ---------- */
.dim { position: relative; height: 52px; margin-top: clamp(32px, 4.4vh, 58px); border-bottom: 1px solid var(--line); }
.dim::before { content: ""; position: absolute; left: 0; right: 0; bottom: 20px; height: 1px; background: var(--line-2); }
.dim .tick { position: absolute; bottom: 14px; width: 1px; height: 13px; background: var(--line-2); }
.dim .lbl {
  position: absolute;
  bottom: 8px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--paper);
  padding: 0 12px;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--ink-2);
  white-space: nowrap;
}

/* ---------- 数据条 ---------- */
.databand { display: grid; grid-template-columns: repeat(4, 1fr); border-bottom: 1px solid var(--ink); }
.dcell { padding: 32px 24px 30px 0; border-right: 1px solid var(--line); }
.dcell:last-child { border-right: 0; }
.dcell .v { display: flex; align-items: baseline; gap: 6px; }
.dcell .v b {
  font-family: var(--num);
  font-stretch: 87.5%;
  font-weight: 500;
  font-size: clamp(38px, 4vw, 58px);
  line-height: 1;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
}
.dcell .v i { font-style: normal; font-size: 14px; color: var(--ink-2); }
.dcell .k {
  margin-top: 10px;
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  text-transform: uppercase;
}
.dcell .k b {
  display: block;
  font-family: var(--cn);
  font-size: 12.5px;
  font-weight: 400;
  color: var(--ink-2);
  letter-spacing: 0;
  margin-top: 3px;
}

/* ---------- 区块标题 ---------- */
.sec { padding: clamp(64px, 8vh, 108px) 0 0; }
.sec-head { display: flex; align-items: flex-end; gap: 20px; padding-bottom: 20px; border-bottom: 1px solid var(--ink); }
.axis {
  width: 26px;
  height: 26px;
  border: 1px solid var(--ink);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--num);
  font-size: 12px;
  flex: 0 0 auto;
  margin-bottom: 6px;
}
.sec-head h2 { font-size: clamp(26px, 2.9vw, 38px); font-weight: 500; letter-spacing: -0.02em; line-height: 1.2; }
.sec-head .meta {
  margin-left: auto;
  text-align: right;
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  text-transform: uppercase;
  line-height: 1.9;
  padding-bottom: 4px;
}
.sec-head .meta b {
  display: block;
  font-family: var(--cn);
  font-size: 12px;
  font-weight: 400;
  color: var(--ink-2);
  letter-spacing: 0;
}

/* ---------- 解决方案 ---------- */
.sol { display: grid; grid-template-columns: 1fr 420px; gap: 52px; }
.sol-list { border-bottom: 1px solid var(--line); }
.sol-row {
  display: grid;
  grid-template-columns: 44px 1fr auto 30px;
  align-items: center;
  gap: 20px;
  padding: 26px 18px 26px 4px;
  border-top: 1px solid var(--line);
  cursor: pointer;
  transition: background 0.3s, color 0.3s, padding 0.3s;
  color: var(--ink);
}
.sol-row:first-child { border-top: 0; }
.sol-row .idx { font-family: var(--mono); font-size: 11px; color: var(--ink-3); letter-spacing: 0.1em; }
.sol-row .nm { font-size: clamp(20px, 2vw, 25px); font-weight: 500; letter-spacing: -0.01em; line-height: 1.3; }
.sol-row .sp {
  font-family: var(--mono);
  font-size: 10.5px;
  color: var(--ink-3);
  letter-spacing: 0.06em;
  text-align: right;
  line-height: 1.9;
}
.sol-row .ar { font-family: var(--mono); font-size: 13px; opacity: 0; transform: translateX(-6px); transition: 0.3s; }
.sol-row.on { background: var(--ink); color: var(--paper); padding-left: 18px; }
.sol-row.on .idx, .sol-row.on .sp { color: #8e969b; }
.sol-row.on .ar { opacity: 1; transform: none; color: var(--paper); }
.sol-plates { position: sticky; top: 110px; height: 500px; align-self: start; }
.sol-plate {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 0.45s;
  border: 1px solid var(--line-2);
  background: var(--paper-2);
}
.sol-plate.on { opacity: 1; }
.sol-plate svg { width: 100%; height: 100%; display: block; }

/* ---------- 影片带 ---------- */
.film { margin-top: clamp(64px, 8vh, 108px); background: var(--steel); color: #e6e3da; }
.film-in { padding-top: clamp(36px, 5vh, 64px); padding-bottom: clamp(44px, 6vh, 72px); }
.film-head { display: flex; align-items: flex-end; gap: 20px; padding-bottom: 20px; border-bottom: 1px solid rgba(230, 227, 218, 0.28); }
.film-head .axis { border-color: #e6e3da; color: #e6e3da; }
.film-head h2 { font-size: clamp(24px, 2.6vw, 34px); font-weight: 500; letter-spacing: -0.02em; color: #fff; }
.film-head .meta {
  margin-left: auto;
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.16em;
  color: #8c959b;
  text-transform: uppercase;
  text-align: right;
  line-height: 1.9;
}
.film-head .meta b { display: block; font-family: var(--cn); font-size: 12px; font-weight: 400; color: #a8b0b5; letter-spacing: 0; }
.film-intro { margin-top: 18px; max-width: 56ch; font-size: 13.5px; line-height: 1.85; color: #a8b0b5; }
.film-grid { display: grid; grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr); gap: 20px; margin-top: 28px; }
.film-card { position: relative; min-width: 0; overflow: hidden; background: #10161a; border: 1px solid rgba(230, 227, 218, 0.18); }
.film-card video, .film-card img { width: 100%; height: 100%; object-fit: cover; display: block; }
.film-card .cap {
  position: absolute;
  left: 0;
  bottom: 0;
  right: 0;
  padding: 14px 16px;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  background: linear-gradient(to top, rgba(9, 13, 16, 0.88), rgba(9, 13, 16, 0));
}
.film-card .cap b { font-size: 13px; font-weight: 500; color: #fff; }
.film-card .cap span { font-family: var(--mono); font-size: 9px; letter-spacing: 0.14em; color: #8c959b; }
.film-card.big, .film-card.sm { height: clamp(230px, 29vw, 450px); }

/* ---------- 案例 ---------- */
.cases { display: grid; grid-template-columns: repeat(12, 1fr); gap: 44px 24px; margin-top: 34px; }
.case { position: relative; display: block; }
.case .ph {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line-2);
  background: #20272b;
}
.case .ph img, .case .ph video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  filter: saturate(0.82) contrast(1.04) brightness(0.94);
  transition: transform 0.7s cubic-bezier(0.2, 0.8, 0.2, 1), filter 0.5s;
}
.case:hover .ph img, .case:hover .ph video { transform: scale(1.035); filter: saturate(0.95) contrast(1.04) brightness(1); }
.case .ph::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(16, 20, 23, 0.86) 0%, rgba(16, 20, 23, 0.18) 42%, rgba(16, 20, 23, 0.06) 100%);
  pointer-events: none;
}
.case .in {
  position: absolute;
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 0.14em;
  color: rgba(255, 255, 255, 0.82);
  z-index: 2;
}
.case .in.tl { top: 14px; left: 16px; }
.case .in.br { bottom: 14px; right: 16px; }
.case .in.bl { bottom: 14px; left: 16px; color: #fff; font-size: 10px; letter-spacing: 0.1em; }
.case .plate-no {
  position: absolute;
  top: 14px;
  right: 16px;
  z-index: 2;
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 0.14em;
  color: rgba(255, 255, 255, 0.62);
}
.case .meta { display: flex; justify-content: space-between; align-items: baseline; gap: 16px; padding: 14px 0 0; border-top: 1px solid var(--ink); margin-top: 14px; }
.case h3 { font-size: 16.5px; font-weight: 500; letter-spacing: -0.01em; line-height: 1.4; }
.case .no { font-family: var(--mono); font-size: 9.5px; color: var(--ink-3); letter-spacing: 0.14em; white-space: nowrap; }
.case .spec { margin-top: 6px; font-family: var(--mono); font-size: 10.5px; color: var(--ink-3); letter-spacing: 0.05em; }
.c-lg { grid-column: span 7; }
.c-sm { grid-column: span 5; }
.c-md { grid-column: span 6; }
.c-lg .ph, .c-sm .ph { height: 380px; }
.c-md .ph { height: 300px; }

/* 案例筛选 */
.filters { display: flex; gap: 8px; margin-top: 24px; flex-wrap: wrap; }
.filters a {
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.12em;
  padding: 8px 14px;
  border: 1px solid var(--line-2);
  color: var(--ink-2);
  transition: 0.2s;
}
.filters a:hover { border-color: var(--ink); color: var(--ink); }
.filters a.on { background: var(--ink); border-color: var(--ink); color: var(--paper); }

/* ---------- 制造实力 ---------- */
.fab { display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 52px; align-items: start; margin-top: 34px; }
.fab-plate { position: relative; height: 470px; border: 1px solid var(--line-2); overflow: hidden; background: #10161a; }
.fab-plate img, .fab-plate video { display: block; width: 100%; height: 100%; object-fit: cover; filter: saturate(0.85) contrast(1.05); }
.fab-plate .tag {
  position: absolute;
  right: 0;
  bottom: 0;
  background: rgba(16, 20, 23, 0.86);
  border-left: 1px solid rgba(230, 227, 218, 0.2);
  padding: 6px 12px;
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 0.16em;
  color: #a8b0b5;
}
.spec-list { border-top: 1px solid var(--ink); }
.spec-row { display: grid; grid-template-columns: 150px 1fr; gap: 20px; padding: 19px 0; border-bottom: 1px solid var(--line); align-items: baseline; }
.spec-row dt { font-family: var(--mono); font-size: 10px; letter-spacing: 0.16em; color: var(--ink-3); text-transform: uppercase; }
.spec-row dd { font-size: 14.5px; line-height: 1.75; color: var(--ink); }
.spec-row dd b { font-family: var(--num); font-stretch: 87.5%; font-weight: 500; font-size: 17px; letter-spacing: -0.01em; margin: 0 3px; }
.spec-row dd em { font-style: normal; color: var(--ink-3); font-size: 12.5px; margin-left: 8px; }

/* ---------- 甘特 ---------- */
.gantt { margin-top: 34px; border-top: 1px solid var(--ink); }
.gt-scale { display: grid; grid-template-columns: 190px 1fr; align-items: center; padding: 12px 0; border-bottom: 1px solid var(--line); }
.gt-scale .weeks { display: grid; grid-template-columns: repeat(45, 1fr); font-family: var(--mono); font-size: 9px; color: var(--ink-3); letter-spacing: 0.06em; }
.gt-row { display: grid; grid-template-columns: 190px 1fr; align-items: center; padding: 15px 0; border-bottom: 1px solid var(--line); }
.gt-row .lbl { font-size: 14px; }
.gt-row .lbl em { font-family: var(--mono); font-style: normal; font-size: 9.5px; color: var(--ink-3); margin-left: 8px; letter-spacing: 0.1em; }
.gt-track { display: grid; grid-template-columns: repeat(45, 1fr); height: 22px; align-items: center; position: relative; }
.gt-track::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: calc(100% / 15) 100%;
  opacity: 0.7;
}
.gt-bar { height: 9px; background: var(--ink); position: relative; z-index: 1; }
.gt-bar.red { background: var(--red); }
.gt-bar.soft { background: var(--ink-3); }
.gt-note { margin-top: 20px; display: flex; gap: 28px; flex-wrap: wrap; }
.gt-note span { font-family: var(--mono); font-size: 10px; letter-spacing: 0.1em; color: var(--ink-3); }
.gt-note span b { color: var(--red); font-weight: 400; }

/* ---------- 询价单 ---------- */
.rfq { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, .7fr); min-width: 0; border: 1px solid var(--ink); margin-top: 34px; }
.rfq-l { min-width: 0; padding: clamp(26px, 3vw, 44px); border-right: 1px solid var(--ink); }
.rfq-head { display: flex; justify-content: space-between; align-items: baseline; padding-bottom: 18px; border-bottom: 1px solid var(--line-2); }
.rfq-head h3 { font-size: 20px; font-weight: 500; letter-spacing: -0.01em; }
.rfq-fields { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); min-width: 0; gap: 0 32px; margin-top: 8px; }
.field { min-width: 0; border-bottom: 1px solid var(--line-2); padding: 18px 0 12px; display: flex; flex-direction: column; gap: 7px; }
.field.full { grid-column: 1 / -1; }
.field label { font-family: var(--mono); font-size: 9.5px; letter-spacing: 0.16em; color: var(--ink-3); text-transform: uppercase; }
.field input, .field select, .field textarea {
  border: 0;
  background: transparent;
  font-family: var(--cn);
  font-size: 15.5px;
  color: var(--ink);
  outline: none;
  padding: 0;
  width: 100%;
  min-width: 0;
  max-width: 100%;
  resize: none;
  -webkit-appearance: none;
  appearance: none;
}
.field select {
  cursor: pointer;
  padding-right: 22px;
  background-image: linear-gradient(45deg, transparent 50%, #6e7378 50%), linear-gradient(135deg, #6e7378 50%, transparent 50%);
  background-position: calc(100% - 9px) 8px, calc(100% - 4px) 8px;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
}
.field input::placeholder, .field textarea::placeholder { color: #a8a398; }
.rfq-f { margin-top: 26px; display: flex; align-items: center; gap: 18px; flex-wrap: wrap; }
.rfq-f .note { font-family: var(--mono); font-size: 9.5px; color: var(--ink-3); letter-spacing: 0.1em; }
.rfq-r { min-width: 0; padding: clamp(26px, 3vw, 44px); background: var(--steel); color: #e6e3da; display: flex; flex-direction: column; }
.rfq-r .mono { color: #8c959b; }
.rfq-r .pledge { list-style: none; margin-top: 22px; }
.rfq-r .pledge li { padding: 14px 0; border-bottom: 1px solid rgba(230, 227, 218, 0.16); display: flex; justify-content: space-between; gap: 14px; align-items: baseline; }
.rfq-r .pledge li:last-child { border-bottom: 0; }
.rfq-r .pledge b { font-family: var(--num); font-stretch: 87.5%; font-size: 19px; font-weight: 500; color: #fff; }
.rfq-r .pledge span { font-size: 12.5px; color: #a8b0b5; }
.rfq-tel { margin-top: auto; padding-top: 28px; }
.rfq-tel .n { font-family: var(--num); font-stretch: 87.5%; font-size: clamp(24px, 2.4vw, 31px); font-weight: 500; color: #fff; margin-top: 6px; }

/* ---------- 表单反馈 ---------- */
.form-msg { margin-top: 18px; font-size: 13.5px; padding: 12px 16px; border-left: 2px solid var(--ink); background: var(--paper-2); }
.form-msg.err { border-color: var(--red); color: var(--red); }
.form-msg.ok { border-color: #2f6b4f; color: #2f6b4f; }

/* ---------- 页脚标题栏 ---------- */
.foot { padding-top: clamp(56px, 7vh, 88px); padding-bottom: 40px; }
.tblock { border: 1px solid var(--ink); background: var(--paper); }
.tb-row { display: grid; border-bottom: 1px solid var(--ink); }
.tb-row.tb-a { grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr) minmax(0, 1fr) minmax(0, .8fr) minmax(0, 1fr); }
.tb-row.tb-b { grid-template-columns: minmax(0, 2.2fr) minmax(0, 1fr) minmax(0, 1.2fr) minmax(0, 1.4fr) minmax(0, 1fr); }
.tb-row:last-child { border-bottom: 0; }
.tb-c { min-width: 0; padding: 16px 18px; border-right: 1px solid var(--line); }
.tb-c:last-child { border-right: 0; }
.tb-c .l { font-family: var(--mono); font-size: 8.5px; letter-spacing: 0.18em; color: var(--ink-3); text-transform: uppercase; }
.tb-c .v { margin-top: 5px; font-size: 12.5px; color: var(--ink); line-height: 1.5; overflow-wrap: anywhere; }
.tb-c .v.big { font-size: 15px; font-weight: 500; }
.foot-nav { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 32px; margin-bottom: 44px; }
.foot-nav h4 { font-size: 13px; font-weight: 500; margin-bottom: 14px; }
.foot-nav ul { list-style: none; }
.foot-nav li { margin-bottom: 8px; }
.foot-nav a { font-size: 12.5px; color: var(--ink-2); }
.foot-nav a:hover { color: var(--ink); text-decoration: underline; }
.foot-note { margin-top: 18px; display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap; font-family: var(--mono); font-size: 9.5px; letter-spacing: 0.1em; color: var(--ink-3); }

/* ---------- 内页页头 ---------- */
.phead { padding: clamp(36px, 5vh, 60px) 0 0; }
.phead h1 { font-size: clamp(30px, 3.6vw, 52px); line-height: 1.16; }
.phead .lede { margin-top: 18px; max-width: 62ch; color: var(--ink-2); font-size: 15px; line-height: 1.85; }
.crumb { display: flex; gap: 10px; align-items: center; font-family: var(--mono); font-size: 9.5px; letter-spacing: 0.14em; color: var(--ink-3); text-transform: uppercase; margin-bottom: 22px; }
.crumb a:hover { color: var(--ink); }
.crumb span.sep { color: var(--line-2); }

/* ---------- 案例详情 ---------- */
.case-hero { margin-top: 34px; position: relative; border: 1px solid var(--line-2); overflow: hidden; background: #10161a; height: clamp(300px, 46vh, 520px); }
.case-hero img, .case-hero video { width: 100%; height: 100%; object-fit: cover; filter: saturate(0.85) contrast(1.04); }
.case-hero .tag {
  position: absolute;
  left: 0;
  bottom: 0;
  background: rgba(16, 20, 23, 0.88);
  padding: 7px 14px;
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 0.16em;
  color: #a8b0b5;
}
.facts { display: grid; grid-template-columns: repeat(6, 1fr); border-bottom: 1px solid var(--ink); margin-top: 0; }
.fact { padding: 22px 16px 20px 0; border-right: 1px solid var(--line); }
.fact:last-child { border-right: 0; }
.fact .k { font-family: var(--mono); font-size: 9px; letter-spacing: 0.16em; color: var(--ink-3); text-transform: uppercase; }
.fact .v { margin-top: 8px; font-family: var(--num); font-stretch: 87.5%; font-size: clamp(17px, 1.7vw, 22px); font-weight: 500; letter-spacing: -0.01em; }
.case-body { display: grid; grid-template-columns: 1fr 320px; gap: 56px; margin-top: 44px; align-items: start; }
.case-body .txt p { margin-bottom: 20px; font-size: 15.5px; line-height: 1.95; color: var(--ink-2); max-width: 62ch; }
.case-side { border-top: 1px solid var(--ink); }
.case-side .row { display: flex; justify-content: space-between; gap: 16px; padding: 13px 0; border-bottom: 1px solid var(--line); font-size: 12.5px; }
.case-side .row span:first-child { font-family: var(--mono); font-size: 9.5px; letter-spacing: 0.14em; color: var(--ink-3); text-transform: uppercase; }
.gallery { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 16px; margin-top: 44px; }
.gallery img { width: 100%; height: 260px; object-fit: cover; border: 1px solid var(--line-2); filter: saturate(0.85) contrast(1.04); }
.case-nav { display: flex; justify-content: space-between; gap: 20px; margin-top: 64px; padding-top: 22px; border-top: 1px solid var(--ink); }
.case-nav a { font-size: 14px; }
.case-nav a:hover { color: var(--red); }
.case-nav .mono { display: block; margin-bottom: 6px; }

/* ---------- 解决方案详情 ---------- */
.sol-detail { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 56px; margin-top: 44px; align-items: start; }
.sol-detail .txt p { font-size: 15.5px; line-height: 1.95; color: var(--ink-2); margin-bottom: 20px; }
.sol-points { margin-top: 34px; border-top: 1px solid var(--ink); }
.sol-points .pt { display: grid; grid-template-columns: 120px 1fr; gap: 20px; padding: 18px 0; border-bottom: 1px solid var(--line); align-items: baseline; }
.sol-points .pt dt { font-family: var(--mono); font-size: 9.5px; letter-spacing: 0.16em; color: var(--ink-3); text-transform: uppercase; }
.sol-points .pt dd { font-size: 14.5px; line-height: 1.8; }
.related { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 34px; }

/* ---------- 关于 ---------- */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; margin-top: 44px; align-items: start; }
.about-img { position: relative; border: 1px solid var(--line-2); overflow: hidden; height: 460px; background: #10161a; }
.about-img img { width: 100%; height: 100%; object-fit: cover; filter: saturate(0.8) contrast(1.05); }
.about-img .tag {
  position: absolute;
  right: 0;
  bottom: 0;
  background: rgba(16, 20, 23, 0.88);
  padding: 6px 12px;
  font-family: var(--mono);
  font-size: 9px;
  letter-spacing: 0.16em;
  color: #a8b0b5;
}
.about-grid .txt p { font-size: 15.5px; line-height: 1.95; color: var(--ink-2); margin-bottom: 18px; }
.timeline { margin-top: 64px; border-top: 1px solid var(--ink); }
.tl-row { display: grid; grid-template-columns: 90px 1fr; gap: 24px; padding: 20px 0; border-bottom: 1px solid var(--line); align-items: baseline; }
.tl-row .y { font-family: var(--num); font-stretch: 87.5%; font-size: 26px; font-weight: 500; letter-spacing: -0.02em; }
.tl-row .t { font-size: 14.5px; color: var(--ink-2); }
.svc { display: grid; grid-template-columns: repeat(5, 1fr); gap: 0; margin-top: 34px; border-top: 1px solid var(--ink); border-bottom: 1px solid var(--ink); }
.svc div {
  padding: 24px 18px;
  border-right: 1px solid var(--line);
  font-size: 13.5px;
  line-height: 1.6;
}
.svc div:last-child { border-right: 0; }
.svc div span { display: block; font-family: var(--mono); font-size: 9px; color: var(--ink-3); letter-spacing: 0.16em; margin-bottom: 10px; }

/* ---------- 联系页 ---------- */
.contact-grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 56px; margin-top: 44px; align-items: start; }
.contact-grid.contact-split { grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr); }
.contact-list { border-top: 1px solid var(--ink); }
.contact-list .row { display: grid; grid-template-columns: 110px minmax(0, 1fr); gap: 18px; padding: 18px 0; border-bottom: 1px solid var(--line); align-items: baseline; }
.contact-list .row dt { font-family: var(--mono); font-size: 9.5px; letter-spacing: 0.16em; color: var(--ink-3); text-transform: uppercase; }
.contact-list .row dd { font-size: 15px; }
.map-plate { position: relative; height: 320px; border: 1px solid var(--line-2); margin-top: 24px; overflow: hidden; background: var(--paper-2); }

/* ---------- 响应式 ---------- */
@media (max-width: 1180px) {
  .sol { grid-template-columns: 1fr; }
  .sol-plates { display: none; }
  .fab, .about-grid, .contact-grid, .contact-grid.contact-split, .sol-detail { grid-template-columns: minmax(0, 1fr); gap: 34px; }
  .hero-grid { grid-template-columns: 1fr; gap: 34px; }
  .hero-plate { height: 300px; }
  .film-grid { grid-template-columns: minmax(0, 1fr); }
  .facts { grid-template-columns: repeat(3, 1fr); }
  .fact:nth-child(3n) { border-right: 0; }
  .svc { grid-template-columns: repeat(3, 1fr); }
  .svc div:nth-child(3n) { border-right: 0; }
  .svc div:nth-child(n + 4) { border-top: 1px solid var(--line); }
}
@media (max-width: 900px) {
  .nav { display: none; }
  .menu-btn {
    display: inline-flex;
    margin-left: auto;
    font-family: var(--mono);
    font-size: 10px;
    letter-spacing: 0.14em;
    border: 1px solid var(--ink);
    padding: 9px 12px;
    background: transparent;
    cursor: pointer;
  }
  .hdr-in .btn { display: none; }
  .databand { grid-template-columns: 1fr 1fr; }
  .dcell { border-bottom: 1px solid var(--line); padding-right: 16px; }
  .dcell:nth-child(2n) { border-right: 0; }
  .c-lg, .c-sm, .c-md { grid-column: 1 / -1; }
  .c-lg .ph, .c-sm .ph { height: 300px; }
  .c-md .ph { height: 240px; }
  .rfq { grid-template-columns: minmax(0, 1fr); }
  .rfq-l { border-right: 0; border-bottom: 1px solid var(--ink); }
  .tb-row, .tb-row.tb-a, .tb-row.tb-b { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
  .tb-c { border-bottom: 1px solid var(--line); }
  .gt-row, .gt-scale { grid-template-columns: 120px 1fr; }
  .spec-row { grid-template-columns: 100px 1fr; gap: 14px; }
  .rfq-fields { grid-template-columns: minmax(0, 1fr); }
  .case .meta { flex-direction: column; align-items: flex-start; gap: 4px; }
  .case-body { grid-template-columns: 1fr; gap: 32px; }
  .foot-nav { grid-template-columns: 1fr 1fr; gap: 24px; }
  .related { grid-template-columns: 1fr; }
  .natv { display: none; }
}
@media (max-width: 700px) {
  .sol-row { grid-template-columns: 34px 1fr; gap: 6px 12px; padding: 20px 0; }
  .sol-row .sp { grid-column: 2; text-align: left; font-size: 10px; }
  .sol-row .ar { display: none; }
  .sol-row.on { padding-left: 12px; }
}
@media (max-width: 560px) {
  .hdr-in { height: 64px; gap: 12px; }
  .hdr .btn { padding: 10px 14px; font-size: 12.5px; }
  .hero-plate { display: none; }
  .sheetbar span:nth-child(2) { display: none; }
  .sheetbar { font-size: 9px; letter-spacing: 0.12em; gap: 8px; overflow: hidden; white-space: nowrap; }
  .sheetbar .sb-x { display: none; }
  .dim .lbl { font-size: 9px; letter-spacing: 0.06em; }
  .databand { grid-template-columns: 1fr 1fr; }
  .dcell { padding: 22px 14px 20px 0; }
  .dcell:nth-child(2n) { border-right: 0; padding-left: 14px; }
  .dcell:nth-child(2n + 1) { padding-left: 0; }
  .dcell .v b { font-size: 34px; }
  .sec-head .meta { display: none; }
  .cases { gap: 28px; }
  .c-lg .ph, .c-sm .ph, .c-md .ph { height: 220px; }
  .tb-row, .tb-row.tb-a, .tb-row.tb-b { grid-template-columns: 1fr; }
  .tb-c { border-right: 0; }
  .gt-row, .gt-scale { grid-template-columns: 96px 1fr; }
  .gt-row .lbl { font-size: 12px; }
  .gt-row .lbl em { display: none; }
  .spec-row { grid-template-columns: 1fr; gap: 6px; padding: 14px 0; }
  .facts { grid-template-columns: 1fr 1fr; }
  .fact { border-right: 0; border-bottom: 1px solid var(--line); }
  .svc { grid-template-columns: 1fr 1fr; }
  .film-card.big, .film-card.sm { height: 220px; }
  .foot-nav { grid-template-columns: 1fr; }
  .about-img { height: 300px; }
  .fab-plate { height: 300px; }
  .case-hero { height: 240px; }
  .sol-points .pt { grid-template-columns: 1fr; gap: 6px; }
}

/* 移动端导航抽屉 */
.drawer { position: fixed; inset: 0; z-index: 80; background: var(--paper); display: none; flex-direction: column; padding: 24px clamp(20px, 5vw, 32px); }
.drawer.open { display: flex; }
.drawer .dr-top { display: flex; justify-content: space-between; align-items: center; padding-bottom: 22px; border-bottom: 1px solid var(--ink); }
.drawer .dr-top button { font-family: var(--mono); font-size: 11px; letter-spacing: 0.14em; background: transparent; border: 1px solid var(--ink); padding: 8px 12px; cursor: pointer; }
.drawer nav { display: flex; flex-direction: column; margin-top: 16px; }
.drawer nav a { padding: 18px 0; border-bottom: 1px solid var(--line); font-size: 20px; }
.drawer nav a i { font-family: var(--mono); font-size: 10px; font-style: normal; color: var(--ink-3); margin-right: 12px; }