/* 骨架: 左侧栏(分组可折叠) + 顶栏 + 内容区; 窄屏侧栏变抽屉 */
.app { display: flex; min-height: 100vh; }

.side { width: 260px; flex: none; background: var(--side-bg); border-right: 1px solid var(--line); display: flex; flex-direction: column; position: sticky; top: 0; height: 100vh; overflow-y: auto; z-index: 30; }
.brand { display: flex; align-items: center; gap: 12px; }
.side__brand { padding: 16px 20px; border-bottom: 1px solid var(--line); background: linear-gradient(180deg, var(--surface-2), var(--side-bg)); }
.brand__mark { width: 34px; height: 34px; border-radius: var(--radius); background: var(--grad); color: var(--on-primary); display: grid; place-items: center; flex: none; box-shadow: inset 0 1px 0 rgba(255, 255, 255, .3); }
.brand__mark .icon { width: 18px; height: 18px; }
.brand__name { display: block; font-family: var(--display); font-weight: 800; font-size: 14px; letter-spacing: .06em; color: var(--text); }
.brand__sub { display: block; font-size: 10px; font-weight: 600; letter-spacing: .12em; text-transform: uppercase; color: var(--primary); }
.side__label { display: flex; justify-content: space-between; align-items: center; padding: 18px 24px 8px; font-size: 10px; font-weight: 700; letter-spacing: .16em; text-transform: uppercase; color: var(--dim); }
.side__label::after { content: ""; width: 6px; height: 6px; border-radius: 50%; background: var(--primary); }

.nav { display: flex; flex-direction: column; gap: 4px; padding: 0 14px 20px; }
.nav__item { display: flex; align-items: center; gap: 10px; padding: 7px 10px; border: 1px solid transparent; border-radius: var(--radius); color: var(--muted); font-size: 13px; font-weight: 500; cursor: pointer; }
.nav__item:hover { background: var(--surface-2); color: var(--text); text-decoration: none; }
.nav__icon { width: 26px; height: 26px; border-radius: var(--radius); border: 1px solid var(--line); background: var(--surface-2); color: var(--primary); display: grid; place-items: center; flex: none; }
.nav__text { flex: 1; min-width: 0; }
.nav__badge { background: var(--danger); color: #fff; border-radius: 999px; padding: 0 7px; font-size: 11px; font-weight: 600; }

/* 分组: 原生 <details>, 展开/收起不用 JS */
.nav__group > summary { list-style: none; }
.nav__group > summary::-webkit-details-marker { display: none; }
.nav__chev { width: 14px; height: 14px; color: var(--dim); transition: transform .2s; }
.nav__group[open] .nav__chev { transform: rotate(180deg); }
.nav__sub { display: flex; flex-direction: column; gap: 2px; margin: 2px 0 4px 22px; padding-left: 14px; border-left: 1px solid var(--line); }
.nav__sub .nav__item { position: relative; padding: 6px 10px; font-size: 12.5px; }
.nav__sub .nav__item::before { content: ""; position: absolute; left: -15px; top: 50%; width: 8px; height: 1px; background: var(--line-strong); }

.nav__item--active, .nav__item--active:hover { color: var(--primary-strong); font-weight: 600; background: var(--primary-soft); border-color: var(--line-strong); }
.nav__sub .nav__item--active::before { left: -15px; width: 12px; height: 2px; background: var(--primary); }
.nav__group--active > summary { color: var(--primary-strong); font-weight: 600; }

.main { flex: 1; min-width: 0; display: flex; flex-direction: column; }
.top { height: 56px; flex: none; display: flex; align-items: center; gap: 12px; padding: 0 24px; background: var(--surface); border-bottom: 1px solid var(--line); position: sticky; top: 0; z-index: 20; }
.top__crumb { flex: 1; min-width: 0; font-size: 13px; color: var(--muted); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.top__crumb b { color: var(--text); font-family: var(--display); font-size: 15px; font-weight: 600; }
.top__user { display: flex; align-items: center; gap: 10px; }
.icon-btn.top__menu { display: none; }
.avatar { width: 32px; height: 32px; border-radius: 50%; background: var(--grad); color: var(--on-primary); display: grid; place-items: center; font-weight: 700; font-size: 13px; text-transform: uppercase; }
.who { display: flex; flex-direction: column; line-height: 1.25; }
.who b { font-size: 13px; }
.who small { font-size: 11px; color: var(--primary); text-transform: uppercase; letter-spacing: .06em; }

.content { padding: 24px; flex: 1; min-height: 0; }

.toolbar { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 16px; }
.toolbar__spacer { flex: 1; }
.grid { display: grid; gap: 16px; }
.grid--stats { grid-template-columns: repeat(auto-fill, minmax(210px, 1fr)); }
.grid--2 { grid-template-columns: 1fr 1fr; }
.split { display: grid; grid-template-columns: 280px 1fr; gap: 16px; align-items: start; }

/* 窄屏: 侧栏变左侧抽屉, 顶栏出菜单按钮 */
.side-mask { display: none; }
@media (max-width: 900px) {
  .side { position: fixed; left: 0; top: 0; transform: translateX(-100%); transition: transform .25s; box-shadow: var(--shadow-lg); }
  .app--nav-open .side { transform: none; }
  .app--nav-open .side-mask { display: block; position: fixed; inset: 0; background: var(--backdrop); z-index: 25; }
  .top { padding: 0 14px; }
  .icon-btn.top__menu { display: inline-grid; }
  .who { display: none; }
  .content { padding: 14px; }
  .grid--2, .split { grid-template-columns: 1fr; }
  .table th, .table td { white-space: nowrap; }
}