/* ============================================================
   音乐实验室 · 学生端样式（实验中心 + 实验运行）
   ============================================================
   与 tower.css 同一套暖纸质配色（--paper / --ink / --gold）。
   手机端（<760px）自动切换为单栏卡片。
   ============================================================ */

.lab-host {
  --l-paper: #efeee3;
  --l-white: #faf9f2;
  --l-ink: #2c4034;
  --l-soft: #7a806d;
  --l-line: #d9dccd;
  --l-gold: #a87c4b;
  --l-green: #526d4e;
  --l-tip: #eaf0e2;
  --l-warn: #f4ead9;
  color: var(--l-ink);
  font-family: 'Microsoft YaHei', 'PingFang SC', system-ui, sans-serif;
  font-size: 15px;
  line-height: 1.8;
  padding: 4px 2px 24px;
}
.lab-host *, .lab-host *::before, .lab-host *::after { box-sizing: border-box; }
.lab-host button { font-family: inherit; cursor: pointer; }
.lab-host img { max-width: 100%; }

.lab-loading, .lab-empty {
  text-align: center;
  padding: 64px 20px;
  color: var(--l-soft);
  background: var(--l-white);
  border: 1px solid var(--l-line);
  border-radius: 14px;
}
.lab-loading b, .lab-empty b {
  display: block;
  color: var(--l-ink);
  font-size: 17px;
  margin-bottom: 6px;
}

/* ---------- 顶部 ---------- */
.lab-top {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 12px;
  margin: 6px 0 14px;
  flex-wrap: wrap;
}
.lab-top-title h2 { margin: 0; font-size: 22px; }
.lab-top-title p { margin: 2px 0 0; color: var(--l-soft); font-size: 13px; }
.lab-view-switch { display: flex; gap: 4px; background: var(--l-white); border: 1px solid var(--l-line); border-radius: 10px; padding: 3px; }
.lab-view-switch button {
  border: 0; background: none; border-radius: 7px;
  width: 34px; height: 30px; font-size: 15px; color: var(--l-soft);
}
.lab-view-switch button.on { background: var(--l-green); color: #fff; }

/* ---------- 筛选 ---------- */
.lab-filters {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  margin-bottom: 14px;
}
.lab-filters label { font-size: 13px; color: var(--l-soft); }
.lab-filters select {
  font-family: inherit; font-size: 13px; color: var(--l-ink);
  background: var(--l-white); border: 1px solid var(--l-line);
  border-radius: 8px; padding: 5px 8px;
}
.lab-count { margin-left: auto; font-size: 13px; color: var(--l-soft); }

/* ---------- 卡片网格 ---------- */
.lab-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 14px;
}
.lab-featured-head {
  font-size: 14px; font-weight: 600; color: var(--l-gold);
  margin: 18px 0 10px;
}
.lab-featured-head:first-of-type { margin-top: 0; }
.lab-group h3 {
  font-size: 15px; color: var(--l-green);
  border-bottom: 1px solid var(--l-line);
  padding-bottom: 6px; margin: 20px 0 12px;
}

.lab-card {
  background: var(--l-white);
  border: 1px solid var(--l-line);
  border-radius: 14px;
  overflow: hidden;
  cursor: pointer;
  transition: transform .16s ease, box-shadow .16s ease;
  display: flex; flex-direction: column;
}
.lab-card:hover, .lab-card:focus-visible {
  transform: translateY(-3px);
  box-shadow: 0 10px 22px rgba(44, 64, 52, .14);
  outline: none;
  border-color: var(--l-gold);
}
.lab-card-cover { width: 100%; height: 132px; object-fit: cover; display: block; background: var(--l-tip); }
.lab-card-placeholder {
  display: flex; align-items: center; justify-content: center;
  font-size: 40px; color: var(--l-green); opacity: .55;
  background: linear-gradient(160deg, #e7eddf, #dde5d2);
}
.lab-card-body { padding: 12px 14px 14px; display: flex; flex-direction: column; gap: 4px; flex: 1; }
.lab-card-body h4 { margin: 0; font-size: 16px; line-height: 1.4; }
.lab-star { font-style: normal; font-size: 13px; }
.lab-sub { margin: 0; font-size: 13px; color: var(--l-gold); }
.lab-meta { font-size: 12px; color: var(--l-soft); display: flex; flex-wrap: wrap; gap: 4px; }
.lab-desc {
  margin: 4px 0 0; font-size: 13px; color: var(--l-soft);
  line-height: 1.65; flex: 1;
}
.lab-card-foot { margin-top: 8px; }
.lab-go { font-size: 13px; color: var(--l-green); font-weight: 600; }
.lab-card:hover .lab-go { text-decoration: underline; }

/* ---------- 紧凑列表 ---------- */
.lab-rows { display: flex; flex-direction: column; gap: 8px; }
.lab-rows .lab-card { flex-direction: row; align-items: stretch; }
.lab-rows .lab-card-cover, .lab-rows .lab-card-placeholder { width: 130px; height: auto; min-height: 84px; flex: none; }
.lab-rows .lab-card-body { padding: 10px 14px; }

/* ---------- 运行页 ---------- */
.lab-run {
  display: flex; flex-direction: column;
  height: 100%; min-height: 480px;
  background: var(--l-white);
  border: 1px solid var(--l-line);
  border-radius: 14px;
  overflow: hidden;
}
.lab-run-top {
  display: flex; align-items: center; gap: 12px;
  padding: 10px 14px;
  background: var(--l-tip);
  border-bottom: 1px solid var(--l-line);
  flex-wrap: wrap;
}
.lab-run-back {
  border: 1px solid var(--l-line); background: var(--l-white);
  color: var(--l-green); font-weight: 600;
  border-radius: 9px; padding: 6px 12px; font-size: 13px;
}
.lab-run-back:hover { border-color: var(--l-green); }
.lab-run-title { flex: 1; min-width: 160px; }
.lab-run-title b { font-size: 15px; }
.lab-run-title span { display: block; font-size: 12px; color: var(--l-soft); }
.lab-run-acts { display: flex; gap: 6px; }
.lab-run-acts button {
  border: 1px solid var(--l-line); background: var(--l-white);
  border-radius: 9px; padding: 6px 10px; font-size: 13px; color: var(--l-ink);
}
.lab-run-acts button:hover { border-color: var(--l-gold); }

.lab-run-stage {
  position: relative; flex: 1;
  background: repeating-conic-gradient(#f3f2e8 0 25%, #eceade 0 50%) 0 0 / 22px 22px;
}
.lab-run-frame {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  border: 0; background: #fff;
  opacity: 0; transition: opacity .25s ease;
}
.lab-run-frame.on { opacity: 1; }
.lab-run-loading {
  position: absolute; inset: 0;
  display: flex; align-items: center; justify-content: center; gap: 10px;
  color: var(--l-soft); background: var(--l-white); font-size: 14px;
}
.lab-spin {
  width: 18px; height: 18px; border-radius: 50%;
  border: 3px solid var(--l-line); border-top-color: var(--l-green);
  animation: lab-spin 0.9s linear infinite;
}
@keyframes lab-spin { to { transform: rotate(360deg); } }
.lab-run-error {
  position: absolute; inset: 0;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 8px; text-align: center; padding: 24px;
  background: var(--l-white);
}
.lab-run-error b { font-size: 17px; }
.lab-run-error p { margin: 0; color: var(--l-soft); font-size: 14px; max-width: 420px; }
.lab-retry {
  margin-top: 10px; border: 0; background: var(--l-green); color: #fff;
  border-radius: 9px; padding: 8px 18px; font-size: 14px;
}

/* ---------- 说明弹窗 ---------- */
.lab-modal {
  position: fixed; inset: 0; z-index: 90;
  background: rgba(30, 40, 33, .45);
  display: flex; align-items: center; justify-content: center;
  padding: 20px;
}
.lab-modal-box {
  width: min(560px, 100%);
  background: var(--l-white);
  border-radius: 14px; border: 1px solid var(--l-line);
  max-height: 80vh; display: flex; flex-direction: column;
}
.lab-modal-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 16px; border-bottom: 1px solid var(--l-line);
}
.lab-modal-head button { border: 0; background: none; font-size: 20px; color: var(--l-soft); }
.lab-modal-body { padding: 14px 16px; overflow: auto; }
.lab-modal-body h5 { margin: 10px 0 4px; color: var(--l-green); font-size: 13px; }
.lab-modal-body p { margin: 0 0 6px; font-size: 14px; }

/* ---------- 手机端：单栏 ---------- */
@media (max-width: 760px) {
  .lab-grid { grid-template-columns: 1fr; }
  .lab-rows .lab-card { flex-direction: column; }
  .lab-rows .lab-card-cover, .lab-rows .lab-card-placeholder { width: 100%; height: 120px; }
  .lab-run { min-height: 420px; }
  .lab-top-title h2 { font-size: 19px; }
}

/* 全屏时撑满 */
.lab-run:fullscreen { border-radius: 0; border: 0; }