:root {
  --bg: #14161a;
  --fg: #e8eaed;
  --muted: #9aa0a6;
  --line: #2a2e35;
  --accent: #4c8dff;
}

* { box-sizing: border-box; }

/* 下面几个覆盖层都是 display:grid，会把 hidden 的默认样式顶掉，必须显式压回去。 */
[hidden] { display: none !important; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 15px/1.5 system-ui, "PingFang SC", "Microsoft YaHei", sans-serif;
}

header {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 20px;
  background: rgba(20, 22, 26, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}

h1 { margin: 0; font-size: 18px; font-weight: 600; }

.tools { display: flex; gap: 8px; }

button {
  font: inherit;
  color: var(--fg);
  background: #23272e;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 7px 14px;
  cursor: pointer;
}

button:hover { border-color: #454b55; }

button.primary { background: var(--accent); border-color: var(--accent); color: #fff; }

main { padding: 20px; }

.up-box {
  border: 1px dashed var(--line);
  border-radius: 12px;
  padding: 16px 18px;
  margin-bottom: 22px;
}

.up-text { color: var(--muted); margin-bottom: 10px; }
.up-text span { display: block; font-size: 13px; opacity: 0.75; }

#upList { list-style: none; margin: 0; padding: 0; display: grid; gap: 4px; }
#upList li { display: flex; justify-content: space-between; gap: 16px; font-size: 13px; }
#upList .fn { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--muted); }
#upList .st { flex: none; }

#gallery { columns: 4 220px; column-gap: 12px; }

.card { position: relative; margin: 0 0 12px; break-inside: avoid; }

.card img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 10px;
  cursor: zoom-in;
  background: #1d2126;
}

.card .del {
  position: absolute;
  top: 8px;
  right: 8px;
  padding: 3px 9px;
  font-size: 12px;
  border-radius: 6px;
  background: rgba(0, 0, 0, 0.62);
  opacity: 0;
}

.card:hover .del { opacity: 1; }

.empty { color: var(--muted); text-align: center; padding: 60px 0; }

.drop-hint {
  position: fixed;
  inset: 0;
  z-index: 20;
  display: grid;
  place-items: center;
  font-size: 20px;
  color: #fff;
  background: rgba(76, 141, 255, 0.18);
  border: 2px dashed var(--accent);
  pointer-events: none;
}

#lightbox {
  position: fixed;
  inset: 0;
  z-index: 30;
  display: grid;
  place-items: center;
  background: rgba(8, 9, 11, 0.94);
}

#lightbox figure { margin: 0; display: grid; justify-items: center; gap: 10px; }

#lbImg { max-width: 92vw; max-height: 82vh; border-radius: 8px; }

#lightbox figcaption { display: flex; gap: 16px; color: var(--muted); font-size: 13px; }
#lightbox figcaption a { color: var(--accent); }

.lb-btn {
  position: fixed;
  background: transparent;
  border: none;
  color: #fff;
  font-size: 30px;
  line-height: 1;
  padding: 10px 16px;
  opacity: 0.65;
}
.lb-btn:hover { opacity: 1; border: none; }
.lb-close { top: 10px; right: 12px; font-size: 22px; }
.lb-prev { left: 6px; top: 50%; transform: translateY(-50%); }
.lb-next { right: 6px; top: 50%; transform: translateY(-50%); }

@media (max-width: 640px) {
  main { padding: 12px; }
  #gallery { columns: 2 140px; }
  .card .del { opacity: 1; }
}