/* 某部综合楼改造 · 作品展示
   配色取自工程封面（深蓝科技底），内容区走浅色专业版面 */

:root {
  --navy-900: #071733;
  --navy-800: #0b2350;
  --navy-700: #123a72;
  --blue-600: #1f5fbf;
  --blue-500: #2b7de9;
  --blue-050: #eaf2fe;
  --ink:      #16202e;
  --ink-2:    #4a5768;
  --ink-3:    #8b96a6;
  --line:     #e3e8f0;
  --bg:       #f5f7fb;
  --card:     #ffffff;
  --radius:   14px;
  --shadow:   0 1px 2px rgba(16,32,64,.04), 0 8px 24px -12px rgba(16,32,64,.18);
  --shadow-lg:0 24px 60px -24px rgba(7,23,51,.45);
  --maxw:     1240px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 76px; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }

.wrap { width: min(100% - 48px, var(--maxw)); margin-inline: auto; }

/* ---------------- 顶部导航 ---------------- */
.nav {
  position: fixed; inset: 0 0 auto 0; z-index: 60;
  height: 64px; display: flex; align-items: center;
  background: rgba(255,255,255,0);
  border-bottom: 1px solid transparent;
  transition: background .3s, border-color .3s, box-shadow .3s;
}
.nav.is-solid {
  background: rgba(255,255,255,.9);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom-color: var(--line);
  box-shadow: 0 6px 24px -18px rgba(16,32,64,.4);
}
.nav__inner { display: flex; align-items: center; gap: 28px; width: min(100% - 48px, var(--maxw)); margin-inline: auto; }
.nav__brand { font-weight: 700; letter-spacing: .06em; font-size: 15px; color: #fff; transition: color .3s; white-space: nowrap; }
.nav.is-solid .nav__brand { color: var(--navy-800); }
.nav__brand small { display: block; font-weight: 400; font-size: 11px; letter-spacing: .22em; opacity: .72; }
.nav__links { display: flex; gap: 4px; margin-left: auto; flex-wrap: wrap; }
.nav__links a {
  padding: 7px 13px; border-radius: 999px; font-size: 13.5px; color: rgba(255,255,255,.82);
  transition: background .2s, color .2s;
}
.nav.is-solid .nav__links a { color: var(--ink-2); }
.nav__links a:hover { background: rgba(255,255,255,.14); color: #fff; }
.nav.is-solid .nav__links a:hover { background: var(--blue-050); color: var(--blue-600); }
.nav__links a.is-active { background: rgba(255,255,255,.18); color: #fff; font-weight: 600; }
.nav.is-solid .nav__links a.is-active { background: var(--blue-050); color: var(--blue-600); }

/* ---------------- 封面 ---------------- */
.hero {
  position: relative; min-height: 100svh; display: flex; align-items: center;
  color: #fff; overflow: hidden; isolation: isolate;
}
.hero__bg {
  position: absolute; inset: 0; z-index: -2;
  background-image: url("assets/effect/p19.jpg");
  background-size: cover; background-position: center 46%;
  transform: scale(1.04);
  filter: saturate(.9) contrast(1.02);
}
.hero__veil {
  position: absolute; inset: 0; z-index: -1;
  background:
    radial-gradient(115% 85% at 82% 8%, rgba(43,125,233,.34) 0%, rgba(7,23,51,0) 58%),
    linear-gradient(105deg, rgba(5,16,36,.94) 0%, rgba(7,23,51,.86) 42%, rgba(7,23,51,.62) 100%),
    linear-gradient(180deg, rgba(7,23,51,.55) 0%, rgba(5,16,36,.72) 100%);
}
.hero__inner { padding: 120px 0 96px; }
.hero__eyebrow {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: 12.5px; letter-spacing: .28em; text-transform: uppercase;
  color: #9fc4ff; border: 1px solid rgba(159,196,255,.34);
  padding: 7px 16px; border-radius: 999px; margin-bottom: 30px;
  background: rgba(159,196,255,.07);
}
.hero h1 {
  margin: 0; font-size: clamp(38px, 7.2vw, 82px); line-height: 1.06;
  letter-spacing: .06em; font-weight: 800; text-shadow: 0 6px 40px rgba(0,0,0,.4);
}
.hero h1 em { font-style: normal; display: block; font-size: .3em; letter-spacing: .5em; font-weight: 500; color: #a9c9ff; margin-top: 22px; }
.hero__lead {
  max-width: 640px; margin: 30px 0 0; font-size: clamp(15px, 1.5vw, 17.5px);
  color: rgba(233,240,252,.9); line-height: 1.85;
}
.hero__facts { display: flex; flex-wrap: wrap; gap: 14px 34px; margin-top: 46px; }
.hero__fact { border-left: 2px solid rgba(159,196,255,.5); padding-left: 14px; }
.hero__fact b { display: block; font-size: 26px; font-weight: 700; letter-spacing: .02em; line-height: 1.2; }
.hero__fact span { font-size: 12.5px; color: rgba(200,216,242,.78); letter-spacing: .12em; }
.hero__scroll {
  position: absolute; left: 50%; bottom: 30px; transform: translateX(-50%);
  font-size: 11.5px; letter-spacing: .3em; color: rgba(200,216,242,.62);
  display: flex; flex-direction: column; align-items: center; gap: 8px;
}
.hero__scroll::after {
  content: ""; width: 1px; height: 42px;
  background: linear-gradient(180deg, rgba(200,216,242,.7), rgba(200,216,242,0));
  animation: drop 1.9s ease-in-out infinite;
}
@keyframes drop { 0%,100% { opacity: .25; transform: translateY(-6px); } 50% { opacity: 1; transform: translateY(0); } }

/* ---------------- 区块通用 ---------------- */
.section { padding: 96px 0; }
.section--tint { background: linear-gradient(180deg, #fff 0%, var(--bg) 100%); }
.section--paper { background: var(--card); border-block: 1px solid var(--line); }

.sec-head { display: flex; align-items: flex-end; gap: 26px; flex-wrap: wrap; margin-bottom: 46px; }
.sec-head__idx {
  flex: none; font-size: 12px; letter-spacing: .24em; color: var(--blue-600);
  border: 1px solid #cfe0fa; background: var(--blue-050);
  padding: 5px 12px; border-radius: 999px; font-weight: 600;
}
.sec-head__txt { flex: 1 1 320px; }
.sec-head h2 {
  margin: 0; font-size: clamp(26px, 3.4vw, 38px); letter-spacing: .04em;
  font-weight: 700; color: var(--navy-900); line-height: 1.25;
}
.sec-head p { margin: 10px 0 0; color: var(--ink-2); max-width: 74ch; font-size: 15px; }
.sec-head__rule { flex: none; width: 120px; height: 3px; background: linear-gradient(90deg, var(--blue-500), transparent); border-radius: 3px; margin-bottom: 12px; }

/* ---------------- 概览卡 ---------------- */
.ov { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 18px; }
.ov__card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 24px; box-shadow: var(--shadow); position: relative; overflow: hidden;
}
.ov__card::before {
  content: ""; position: absolute; inset: 0 auto 0 0; width: 3px;
  background: linear-gradient(180deg, var(--blue-500), var(--navy-700));
}
.ov__card b { display: block; font-size: 34px; font-weight: 800; color: var(--navy-800); letter-spacing: .02em; line-height: 1.15; }
.ov__card b i { font-style: normal; font-size: .45em; color: var(--ink-3); margin-left: 5px; font-weight: 600; }
.ov__card span { display: block; margin-top: 8px; font-size: 13.5px; color: var(--ink-2); }
.ov__card em { display: block; margin-top: 3px; font-size: 11.5px; color: var(--ink-3); font-style: normal; letter-spacing: .06em; }

/* ---------------- 布局图 + 规格表 ---------------- */
.plan { display: grid; grid-template-columns: 1.55fr 1fr; gap: 30px; align-items: start; margin-bottom: 56px; }
.plan__fig {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow);
}
.plan__fig img { width: 100%; cursor: zoom-in; }
.plan__cap { padding: 13px 18px; font-size: 12.5px; color: var(--ink-3); border-top: 1px solid var(--line); letter-spacing: .04em; }
.spec { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 8px 24px 20px; box-shadow: var(--shadow); }
.spec h3 { font-size: 15px; margin: 18px 0 6px; color: var(--navy-800); letter-spacing: .06em; }
.spec dl { margin: 0; }
.spec dt { font-size: 14px; font-weight: 700; color: var(--navy-800); margin-top: 16px; display: flex; align-items: center; gap: 8px; }
.spec dt::before { content: ""; width: 6px; height: 6px; border-radius: 50%; background: var(--blue-500); flex: none; }
.spec dd { margin: 4px 0 0 14px; font-size: 13.5px; color: var(--ink-2); line-height: 1.7; }

/* ---------------- 效果图栅格 ---------------- */
.gal { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 20px; }
.gal--wide { grid-template-columns: repeat(auto-fill, minmax(430px, 1fr)); }
.gal--narrow { grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); }

.shot {
  position: relative; background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow);
  cursor: zoom-in; transition: transform .35s cubic-bezier(.2,.7,.3,1), box-shadow .35s, border-color .35s;
}
.shot:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: #cfe0fa; }
.shot__img { width: 100%; aspect-ratio: var(--ar, 16/10); object-fit: cover; background: #eef2f8; }
.shot__meta { padding: 13px 16px 15px; border-top: 1px solid var(--line); display: flex; align-items: baseline; gap: 10px; }
.shot__meta b { font-size: 13.5px; font-weight: 600; color: var(--ink); flex: 1; }
.shot__meta span { font-size: 11.5px; color: var(--ink-3); letter-spacing: .04em; flex: none; }
.shot__no {
  position: absolute; top: 12px; left: 12px; z-index: 2;
  background: rgba(7,23,51,.72); color: #fff; font-size: 11px; letter-spacing: .1em;
  padding: 4px 9px; border-radius: 999px; -webkit-backdrop-filter: blur(6px); backdrop-filter: blur(6px);
}
.shot--flat .shot__meta { display: none; }

/* ---------------- 素材库 ---------------- */
.filters { display: flex; flex-wrap: wrap; gap: 9px; margin-bottom: 28px; }
.chip {
  border: 1px solid var(--line); background: var(--card); color: var(--ink-2);
  padding: 8px 15px; border-radius: 999px; font-size: 13px; cursor: pointer;
  transition: all .2s; font-family: inherit; display: inline-flex; align-items: center; gap: 7px;
}
.chip:hover { border-color: #bcd5f7; color: var(--blue-600); }
.chip.is-on { background: var(--navy-800); border-color: var(--navy-800); color: #fff; font-weight: 600; }
.chip u { text-decoration: none; font-size: 11px; opacity: .6; font-variant-numeric: tabular-nums; }

.libgroup { margin-bottom: 44px; }
.libgroup__head { display: flex; align-items: center; gap: 14px; margin-bottom: 16px; }
.libgroup__head h3 { margin: 0; font-size: 17px; letter-spacing: .05em; color: var(--navy-800); }
.libgroup__head i { font-style: normal; font-size: 12px; color: var(--ink-3); letter-spacing: .1em; }
.libgroup__head::after { content: ""; flex: 1; height: 1px; background: var(--line); }

.lib { display: grid; grid-template-columns: repeat(auto-fill, minmax(158px, 1fr)); gap: 12px; }
.lib__item {
  position: relative; border: 1px solid var(--line); border-radius: 10px; overflow: hidden;
  background: var(--card); cursor: zoom-in; transition: transform .28s, box-shadow .28s, border-color .28s;
}
.lib__item:hover { transform: translateY(-3px); box-shadow: var(--shadow); border-color: #cfe0fa; }
.lib__item img { width: 100%; aspect-ratio: 1/1; object-fit: cover; background: #eef2f8; }
.lib__item figcaption {
  position: absolute; inset: auto 0 0 0; padding: 18px 9px 7px; font-size: 10.5px; color: #fff;
  background: linear-gradient(180deg, rgba(7,23,51,0), rgba(7,23,51,.86));
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis; opacity: 0; transition: opacity .25s;
}
.lib__item:hover figcaption { opacity: 1; }

/* ---------------- 灯箱 ---------------- */
.lb {
  position: fixed; inset: 0; z-index: 200; display: none;
  background: rgba(4,11,24,.94); -webkit-backdrop-filter: blur(6px); backdrop-filter: blur(6px);
}
.lb.is-on { display: grid; grid-template-rows: 1fr auto; }
.lb__stage { position: relative; display: flex; align-items: center; justify-content: center; padding: 58px 84px 12px; min-height: 0; }
.lb__img { max-width: 100%; max-height: 100%; object-fit: contain; border-radius: 6px; box-shadow: 0 30px 80px -30px #000; }
.lb__bar { padding: 16px 28px 22px; color: #e6edf9; display: flex; align-items: center; gap: 18px; flex-wrap: wrap; }
.lb__bar b { font-size: 15px; font-weight: 600; }
.lb__bar span { font-size: 12.5px; color: #93a6c4; letter-spacing: .06em; }
.lb__count { margin-left: auto; font-variant-numeric: tabular-nums; font-size: 12.5px; color: #93a6c4; }
.lb__btn {
  position: absolute; top: 50%; transform: translateY(-50%);
  width: 46px; height: 46px; border-radius: 50%; border: 1px solid rgba(255,255,255,.22);
  background: rgba(255,255,255,.09); color: #fff; font-size: 20px; cursor: pointer;
  display: grid; place-items: center; transition: background .2s, transform .2s; font-family: inherit;
}
.lb__btn:hover { background: rgba(255,255,255,.2); }
.lb__btn--prev { left: 22px; }
.lb__btn--next { right: 22px; }
.lb__close {
  position: absolute; top: 18px; right: 22px; width: 40px; height: 40px; border-radius: 50%;
  border: 1px solid rgba(255,255,255,.22); background: rgba(255,255,255,.09); color: #fff;
  font-size: 18px; cursor: pointer; display: grid; place-items: center; font-family: inherit;
}
.lb__close:hover { background: rgba(255,255,255,.2); }
.lb__hint { position: absolute; top: 26px; left: 28px; font-size: 11.5px; letter-spacing: .16em; color: #7f92b2; }

/* ---------------- 页脚 ---------------- */
.foot { background: var(--navy-900); color: #b9c8e0; padding: 58px 0 44px; }
.foot__grid { display: flex; gap: 40px; flex-wrap: wrap; align-items: flex-start; }
.foot h4 { color: #fff; margin: 0 0 12px; font-size: 15px; letter-spacing: .1em; }
.foot p { margin: 0 0 8px; font-size: 13px; line-height: 1.8; color: #8ea3c4; max-width: 60ch; }
.foot__meta { margin-left: auto; text-align: right; font-size: 12.5px; color: #7f92b2; line-height: 1.9; }
.foot__rule { height: 1px; background: rgba(255,255,255,.1); margin: 34px 0 20px; }
.foot small { font-size: 12px; color: #6f83a3; }

/* ---------------- 滚动浮现 ---------------- */
.rv { opacity: 0; transform: translateY(22px); transition: opacity .7s cubic-bezier(.2,.7,.3,1), transform .7s cubic-bezier(.2,.7,.3,1); }
.rv.is-in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .rv-ready .rv { opacity: 1; transform: none; transition: none; }
  .hero__scroll::after { animation: none; }
}

/* ---------------- 响应式 ---------------- */
@media (max-width: 1000px) {
  .plan { grid-template-columns: 1fr; }
  .nav__links { gap: 0; }
  .nav__links a { padding: 6px 9px; font-size: 12.5px; }
}
@media (max-width: 720px) {
  .wrap { width: calc(100% - 32px); }
  .section { padding: 64px 0; }
  .hero__inner { padding: 104px 0 84px; }
  .gal, .gal--wide { grid-template-columns: 1fr; }
  .lib { grid-template-columns: repeat(auto-fill, minmax(118px, 1fr)); gap: 9px; }
  .lb__stage { padding: 62px 14px 8px; }
  .lb__btn--prev { left: 6px; } .lb__btn--next { right: 6px; }
  .lb__btn { width: 40px; height: 40px; }
  .foot__meta { margin-left: 0; text-align: left; }
}