:root {
  --pku-red: #a71930;
  --pku-red-dark: #751020;
  --ink: #25262a;
  --muted: #6b6e73;
  --line: #dedfe2;
  --paper: #ffffff;
  font-family: Inter, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--paper);
  font-synthesis: none;
}

* {
  box-sizing: border-box;
  word-break: keep-all;
  overflow-wrap: normal;
  hyphens: none;
}
html, body { margin: 0; min-width: 320px; min-height: 100%; background: #fff; }
button { font: inherit; }
button:focus-visible { outline: 3px solid #f4bb45; outline-offset: 3px; }

.page-shell { min-height: 100vh; display: flex; flex-direction: column; }
.site-header {
  min-height: 104px;
  display: grid;
  grid-template-columns: minmax(210px, 300px) 1fr minmax(180px, 250px);
  align-items: center;
  gap: 24px;
  padding: 18px clamp(20px, 3vw, 48px);
  border-bottom: 1px solid var(--line);
}
.brand { display: block; width: min(100%, 285px); height: auto; }
.title-block { text-align: center; }
.title-block h1 { margin: 0; font: 600 clamp(25px, 2.3vw, 38px)/1.05 Georgia, "Times New Roman", "Songti SC", serif; letter-spacing: -.5px; white-space: nowrap; }
.title-block p { margin: 7px 0 0; color: var(--pku-red); font-size: clamp(16px, 1.5vw, 21px); font-weight: 700; letter-spacing: .08em; }
.instruction { justify-self: end; display: flex; align-items: center; gap: 11px; color: var(--muted); font-size: 12px; line-height: 1.45; }
.instruction b { color: var(--pku-red); font-weight: 650; }
.camera-icon { width: 30px; height: 30px; display: grid; place-items: center; border: 1px solid #e4bcc3; border-radius: 50%; color: var(--pku-red); background: #fff4f5; font-size: 12px; }

.map-section { flex: 1; display: grid; place-items: center; align-content: center; padding: clamp(18px, 3vw, 44px); }
.map-frame { position: relative; width: min(100%, 1500px); aspect-ratio: 16 / 9; background: #fff; box-shadow: 0 18px 55px rgba(30, 31, 34, .08); border: 1px solid #ececee; overflow: visible; }
.map-image { display: block; width: 100%; height: 100%; object-fit: contain; user-select: none; }
.map-note { margin: 16px 0 0; color: var(--muted); font-size: 13px; text-align: center; }

.photo-point { position: absolute; width: 32px; height: 32px; padding: 0; border: 0; border-radius: 50%; background: transparent; cursor: pointer; transform: translate(-50%, -50%); z-index: 2; }
.photo-point .dot { position: absolute; inset: 7px; border-radius: 50%; background: var(--pku-red); border: 2px solid #fff; box-shadow: 0 3px 10px rgba(80, 8, 20, .35); transition: transform .18s ease, background .18s ease; }
.photo-point .pulse { position: absolute; inset: 2px; border: 1px solid rgba(167, 25, 48, .34); border-radius: 50%; animation: breathe 2.4s ease-out infinite; }
.photo-point:hover .dot, .photo-point:focus-visible .dot { transform: scale(1.2); background: var(--pku-red-dark); }
.point-label { position: absolute; left: 50%; bottom: calc(100% + 9px); transform: translateX(-50%) translateY(4px); min-width: 152px; padding: 7px 10px; color: #fff; background: rgba(31, 32, 35, .92); border-radius: 5px; font-size: 10px; line-height: 1.35; white-space: nowrap; opacity: 0; pointer-events: none; transition: opacity .16s ease, transform .16s ease; box-shadow: 0 7px 20px rgba(0, 0, 0, .16); }
.photo-point:hover .point-label, .photo-point:focus-visible .point-label { opacity: 1; transform: translateX(-50%) translateY(0); }
.label-left, .label-right { left: auto; right: calc(100% + 8px); bottom: 50%; transform: translateY(50%) translateX(4px); }
.photo-point:hover .label-left, .photo-point:focus-visible .label-left, .photo-point:hover .label-right, .photo-point:focus-visible .label-right { transform: translateY(50%) translateX(0); }
.point-deans { left: 29.5%; top: 74.6%; }
.point-410 { left: 62.25%; top: 53%; }
.point-left { left: 85.56%; top: 69.1%; }
.point-right { left: 85.56%; top: 63.9%; }

.lightbox[hidden] { display: none; }
.lightbox { position: fixed; inset: 0; z-index: 100; display: grid; place-items: center; padding: clamp(12px, 3vw, 36px); }
.lightbox-backdrop { position: absolute; inset: 0; background: rgba(18, 18, 20, .78); backdrop-filter: blur(9px); }
.viewer-card { position: relative; width: min(1180px, 96vw); height: min(860px, 92vh); display: grid; grid-template-rows: auto minmax(0, 1fr) auto; background: #111214; color: #fff; border: 1px solid rgba(255, 255, 255, .16); box-shadow: 0 30px 90px rgba(0, 0, 0, .45); overflow: hidden; border-radius: 12px; }
.viewer-header { min-height: 76px; display: flex; justify-content: space-between; align-items: center; gap: 20px; padding: 14px 16px 14px 22px; background: #fff; color: var(--ink); border-bottom: 1px solid var(--line); }
.viewer-header h2 { margin: 0; font: 600 clamp(20px, 2.2vw, 30px)/1.1 Georgia, "Times New Roman", "Songti SC", serif; white-space: nowrap; }
.viewer-header p { margin: 4px 0 0; color: var(--pku-red); font-size: 14px; font-weight: 650; }
.close-button { flex: 0 0 auto; width: 48px; height: 48px; border: 0; border-radius: 50%; background: #f2f2f3; color: #2f3033; cursor: pointer; font-size: 32px; font-weight: 300; line-height: 1; transition: background .16s ease, color .16s ease, transform .16s ease; }
.close-button:hover { background: var(--pku-red); color: #fff; transform: rotate(4deg); }
.photo-viewport { position: relative; min-height: 0; overflow: hidden; display: grid; place-items: center; background: #17181a; cursor: zoom-in; touch-action: none; }
.photo-viewport.is-zoomed { cursor: grab; }
.photo-viewport.is-dragging { cursor: grabbing; }
#locationPhoto { position: absolute; inset: 0; display: block; width: 100%; height: 100%; object-fit: contain; transform-origin: center center; will-change: transform; user-select: none; -webkit-user-drag: none; pointer-events: none; }
.viewer-toolbar { min-height: 66px; display: flex; justify-content: space-between; align-items: center; gap: 20px; padding: 10px 20px; background: #fff; color: var(--ink); border-top: 1px solid var(--line); }
.viewer-toolbar p { margin: 0; color: var(--muted); font-size: 12px; text-align: right; }
.zoom-group { display: flex; align-items: center; height: 40px; border: 1px solid #d7d8db; border-radius: 6px; overflow: hidden; }
.zoom-group button { height: 100%; min-width: 42px; border: 0; border-right: 1px solid #d7d8db; background: #fff; color: var(--ink); cursor: pointer; font-size: 20px; }
.zoom-group button:hover { background: #fff1f3; color: var(--pku-red); }
.zoom-group button:disabled { color: #b7b8bb; background: #f5f5f5; cursor: default; }
.zoom-group output { min-width: 62px; text-align: center; color: var(--muted); font-size: 12px; }
.zoom-group #resetZoom { padding: 0 14px; border-right: 0; font-size: 12px; font-weight: 650; }
.zoom-group #resetZoom span { color: var(--pku-red); }

@keyframes breathe { 0% { transform: scale(.65); opacity: .8; } 75%, 100% { transform: scale(1.45); opacity: 0; } }

@media (max-width: 760px) {
  .site-header { min-height: auto; grid-template-columns: 1fr auto; gap: 10px; padding: 14px 16px; }
  .brand { width: 150px; }
  .title-block { text-align: right; }
  .title-block h1 { font-size: clamp(15px, 4.8vw, 19px); }
  .title-block p { margin-top: 4px; font-size: 14px; }
  .instruction { display: none; }
  .map-section { padding: 16px 8px 24px; overflow-x: auto; justify-content: start; }
  .map-frame { width: 900px; max-width: none; transform-origin: left top; }
  .map-note { position: sticky; left: 8px; width: calc(100vw - 16px); font-size: 11px; }
  .viewer-card { width: 100%; height: 92dvh; border-radius: 8px; }
  .viewer-header { min-height: 68px; padding-left: 16px; }
  .viewer-header h2 { font-size: 20px; }
  .viewer-header p { font-size: 12px; }
  .close-button { width: 43px; height: 43px; font-size: 29px; }
  .viewer-toolbar { min-height: 62px; padding: 9px 12px; }
  .viewer-toolbar p { display: none; }
  .zoom-group { width: 100%; }
  .zoom-group output { flex: 1; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation: none !important; transition: none !important; }
}