/* ===================================================================
   大事年表 — UI 组件层（弹窗 / 表单 / 列表 / 详情卡 / Toast）
   =================================================================== */

/* ------------------------------ 弹窗骨架 ------------------------------ */

.modal-root {
  position: fixed;
  inset: 0;
  z-index: 80;
  display: grid;
  place-items: center;
  padding: calc(1rem + var(--safe-top)) 1rem calc(1rem + var(--safe-bottom));
  background: var(--mask);
  -webkit-backdrop-filter: blur(3px);
  backdrop-filter: blur(3px);
  animation: fade var(--dur) var(--ease);
}
.modal-root[hidden] { display: none; }

@keyframes fade { from { opacity: 0; } to { opacity: 1; } }
@keyframes rise { from { opacity: 0; transform: translateY(14px) scale(0.985); } to { opacity: 1; transform: none; } }
@keyframes sheet { from { transform: translateY(100%); } to { transform: none; } }

.modal {
  width: min(92vw, 520px);
  max-height: min(86vh, 900px);
  display: flex;
  flex-direction: column;
  border-radius: var(--radius-xl);
  background: var(--glass-strong);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow);
  -webkit-backdrop-filter: blur(22px) saturate(160%);
  backdrop-filter: blur(22px) saturate(160%);
  overflow: hidden;
  animation: rise var(--dur-slow) var(--ease);
}
.modal--sm { width: min(92vw, 400px); }
.modal--lg { width: min(94vw, 720px); }
.modal--xl { width: min(96vw, 940px); }

.modal__head {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.9rem 0.75rem 0.9rem 1.1rem;
  border-bottom: 1px solid var(--line-soft);
  flex: 0 0 auto;
}
.modal__title {
  margin: 0;
  font-size: 1rem;
  font-weight: 650;
  letter-spacing: 0.01em;
  flex: 1 1 auto;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.modal__sub { display: block; font-size: 0.75rem; font-weight: 400; color: var(--text-dim); margin-top: 0.1rem; }
.modal__close { flex: 0 0 auto; }

.modal__body {
  padding: 1rem 1.1rem;
  overflow: auto;
  overscroll-behavior: contain;
  -webkit-overflow-scrolling: touch;
  flex: 1 1 auto;
  min-height: 0;
}

.modal__foot {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 0.5rem;
  padding: 0.75rem 1.1rem;
  border-top: 1px solid var(--line-soft);
  flex: 0 0 auto;
  flex-wrap: wrap;
}
.modal__foot .spacer { flex: 1 1 auto; }

@media (max-width: 640px) {
  .modal-root { place-items: end stretch; padding: 0; }
  .modal {
    width: 100%;
    max-height: 88vh;
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
    animation: sheet var(--dur-slow) var(--ease);
    padding-bottom: var(--safe-bottom);
  }
  .modal--sm, .modal--lg, .modal--xl { width: 100%; }
  .modal__foot { position: sticky; bottom: 0; background: var(--glass-strong); }
}

/* ------------------------------ 表单 ------------------------------ */

.field { display: block; margin-bottom: 0.85rem; }
.field__label {
  display: block;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-dim);
  margin-bottom: 0.3rem;
  letter-spacing: 0.02em;
}
.field__hint { font-size: 0.6875rem; color: var(--text-faint); margin-top: 0.3rem; line-height: 1.5; }
.field__err { font-size: 0.6875rem; color: var(--danger); margin-top: 0.3rem; }

.row { display: grid; gap: 0.6rem; grid-template-columns: 1fr 1fr; }
.row--3 { grid-template-columns: 1fr 1fr 1fr; }
@media (max-width: 520px) {
  .row, .row--3 { grid-template-columns: 1fr; }
}

input[type="text"], input[type="search"], input[type="number"], input[type="date"], select, textarea {
  width: 100%;
  min-height: var(--tap);
  padding: 0.5rem 0.7rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--input-border);
  background: var(--input-bg);
  color: var(--text);
  font-family: inherit;
  font-size: 0.875rem;
  line-height: 1.4;
  outline: none;
  transition: border-color var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}
textarea { min-height: 6.5rem; resize: vertical; padding-top: 0.55rem; }
input:focus, select:focus, textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
input::placeholder, textarea::placeholder { color: var(--text-faint); }
select {
  -webkit-appearance: none;
  appearance: none;
  background-image: linear-gradient(45deg, transparent 50%, var(--text-dim) 50%),
                    linear-gradient(135deg, var(--text-dim) 50%, transparent 50%);
  background-position: calc(100% - 16px) 50%, calc(100% - 11px) 50%;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
  padding-right: 2rem;
}
select option { background: var(--panel); color: var(--text); }

.check {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  min-height: 36px;
  font-size: 0.8125rem;
  color: var(--text);
  cursor: pointer;
  user-select: none;
}
.check input { width: 1.05rem; height: 1.05rem; accent-color: var(--accent); flex: 0 0 auto; }

.btn {
  -webkit-appearance: none;
  appearance: none;
  border: 1px solid var(--input-border);
  background: var(--input-bg);
  color: var(--text);
  font-family: inherit;
  font-size: 0.8125rem;
  font-weight: 550;
  min-height: 38px;
  padding: 0 0.9rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  transition: background var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
  white-space: nowrap;
}
.btn:hover { background: var(--glass-hi); }
.btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.btn--primary { background: var(--accent); border-color: var(--accent); color: var(--accent-text); }
.btn--primary:hover { filter: brightness(1.08); }
.btn--danger { color: var(--danger); border-color: color-mix(in srgb, var(--danger) 40%, transparent); }
.btn--danger:hover { background: var(--danger-soft); }
.btn--ghost { border-color: transparent; background: transparent; }
.btn--ghost:hover { background: var(--glass-hi); }
.btn--sm { min-height: 32px; padding: 0 0.6rem; font-size: 0.75rem; }
.btn[disabled] { opacity: 0.45; cursor: not-allowed; }

/* ------------------------------ 通用块 ------------------------------ */

.sec-title {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-faint);
  text-transform: uppercase;
  margin: 1.1rem 0 0.5rem;
}
.sec-title:first-child { margin-top: 0; }

.list { display: flex; flex-direction: column; gap: 0.375rem; }

.item {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.55rem 0.7rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--line-soft);
  background: var(--input-bg);
  transition: border-color var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);
}
.item:hover { border-color: var(--line); }
.item.is-active { border-color: var(--accent); background: var(--accent-soft); }
.item__bar { width: 3px; align-self: stretch; border-radius: 2px; background: var(--accent); flex: 0 0 auto; }
.item__main { flex: 1 1 auto; min-width: 0; }
.item__title {
  font-size: 0.875rem;
  font-weight: 550;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.item__meta { font-size: 0.6875rem; color: var(--text-dim); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; margin-top: 0.05rem; }
.item__actions { display: flex; gap: 0.2rem; flex: 0 0 auto; }
.item__desc { font-size: 0.8125rem; color: var(--text-dim); margin-top: 0.3rem; line-height: 1.6; }

.pill {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  height: 19px;
  padding: 0 0.45rem;
  border-radius: 999px;
  font-size: 0.6875rem;
  font-weight: 600;
  background: var(--panel-2);
  color: var(--text-dim);
  flex: 0 0 auto;
}
.pill--l1 { background: rgba(224, 90, 79, 0.16); color: #e0716a; }
.pill--l2 { background: rgba(229, 176, 84, 0.16); color: #d9a950; }
.pill--l3 { background: var(--panel-2); color: var(--text-dim); }
.pill--accent { background: var(--accent-soft); color: var(--accent); }

.empty {
  padding: 1.6rem 1rem;
  text-align: center;
  color: var(--text-faint);
  font-size: 0.8125rem;
  line-height: 1.7;
}

/* ------------------------------ 搜索结果 ------------------------------ */

.search-box { position: relative; margin-bottom: 0.75rem; }
.search-box input { padding-left: 2.1rem; }
.search-box svg {
  position: absolute;
  left: 0.7rem; top: 50%; transform: translateY(-50%);
  width: 15px; height: 15px; color: var(--text-faint); pointer-events: none;
}

.result {
  display: block;
  width: 100%;
  text-align: left;
  border: 1px solid transparent;
  background: transparent;
  color: inherit;
  font-family: inherit;
  padding: 0.55rem 0.7rem;
  border-radius: var(--radius-md);
  cursor: pointer;
}
.result:hover { background: var(--glass-hi); }
.result.is-sel { background: var(--accent-soft); border-color: color-mix(in srgb, var(--accent) 40%, transparent); }
.result__top { display: flex; align-items: baseline; gap: 0.45rem; }
.result__time { font-size: 0.75rem; color: var(--accent); font-variant-numeric: tabular-nums; flex: 0 0 auto; }
.result__name { font-size: 0.875rem; font-weight: 600; }
.result__tl { font-size: 0.6875rem; color: var(--text-faint); margin-left: auto; flex: 0 0 auto; }
.result__snip {
  font-size: 0.75rem;
  color: var(--text-dim);
  margin-top: 0.15rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.result mark { background: var(--accent-soft); color: var(--accent); border-radius: 2px; padding: 0 1px; }

/* ------------------------------ 详情卡 ------------------------------ */

.detail {
  position: fixed;
  z-index: 60;
  width: min(90vw, 380px);
  border-radius: var(--radius-lg);
  background: var(--glass-strong);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow);
  -webkit-backdrop-filter: blur(22px) saturate(160%);
  backdrop-filter: blur(22px) saturate(160%);
  animation: rise var(--dur) var(--ease);
  overflow: hidden;
}
.detail__head { padding: 0.85rem 0.9rem 0.7rem; border-bottom: 1px solid var(--line-soft); }
.detail__time { font-size: 0.75rem; color: var(--accent); font-variant-numeric: tabular-nums; margin-bottom: 0.15rem; }
.detail__title { font-size: 1rem; font-weight: 650; line-height: 1.4; }
.detail__body { padding: 0.75rem 0.9rem; font-size: 0.8125rem; line-height: 1.75; color: var(--text-dim); max-height: 34vh; overflow: auto; }
.detail__tags { display: flex; flex-wrap: wrap; gap: 0.3rem; padding: 0 0.9rem 0.7rem; }
.detail__foot { display: flex; gap: 0.35rem; padding: 0.6rem 0.7rem; border-top: 1px solid var(--line-soft); flex-wrap: wrap; }
.detail__foot .btn { flex: 1 1 auto; }

@media (max-width: 640px) {
  .detail {
    left: 0 !important; right: 0 !important;
    bottom: 0 !important; top: auto !important;
    width: 100%;
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
    padding-bottom: var(--safe-bottom);
    animation: sheet var(--dur-slow) var(--ease);
  }
  .detail__body { max-height: 30vh; }
}

/* 聚合节点展开列表 */
.cluster-list { max-height: 52vh; overflow: auto; }

/* ------------------------------ Toast ------------------------------ */

.toast-root {
  position: fixed;
  z-index: 95;
  left: 50%;
  transform: translateX(-50%);
  bottom: calc(5rem + var(--safe-bottom));
  display: flex;
  flex-direction: column-reverse;
  align-items: center;
  gap: 0.4rem;
  pointer-events: none;
  width: max-content;
  max-width: 92vw;
}
.toast {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.55rem 0.9rem;
  border-radius: 999px;
  background: var(--glass-strong);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow);
  -webkit-backdrop-filter: blur(18px);
  backdrop-filter: blur(18px);
  font-size: 0.8125rem;
  color: var(--text);
  animation: rise var(--dur) var(--ease);
  max-width: 92vw;
}
.toast--ok { color: var(--ok); }
.toast--warn { color: var(--warn); }
.toast--err { color: var(--danger); }

/* ------------------------------ 更多面板 / 帮助 ------------------------------ */

.grid-actions {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(104px, 1fr));
  gap: 0.5rem;
}
.grid-actions .btn { min-height: 60px; flex-direction: column; gap: 0.35rem; font-size: 0.75rem; }
.grid-actions .btn svg { width: 20px; height: 20px; }

.kbd-list { display: grid; gap: 0.35rem; }
.kbd-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.8125rem;
  color: var(--text-dim);
  padding: 0.3rem 0;
}
.kbd-row > span:last-child { color: var(--text); }
kbd {
  display: inline-block;
  min-width: 24px;
  padding: 0.1rem 0.4rem;
  border-radius: var(--radius-xs);
  border: 1px solid var(--line);
  border-bottom-width: 2px;
  background: var(--input-bg);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text);
  text-align: center;
}

.note {
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius-md);
  background: var(--input-bg);
  border: 1px solid var(--line-soft);
  font-size: 0.75rem;
  line-height: 1.7;
  color: var(--text-dim);
}
.note--warn { border-color: color-mix(in srgb, var(--warn) 35%, transparent); color: var(--warn); }
.note--danger { border-color: color-mix(in srgb, var(--danger) 35%, transparent); color: var(--danger); }
.note b { color: var(--text); }

.counter { font-size: 0.6875rem; color: var(--text-faint); text-align: right; margin-top: 0.2rem; font-variant-numeric: tabular-nums; }
.counter.is-over { color: var(--danger); }

.scroll-y { max-height: 46vh; overflow: auto; overscroll-behavior: contain; }

/* ===================================================================
   弹窗自适应：避免元素重叠 / 溢出（桌面与手机都适用）
   =================================================================== */

.modal { width: min(92vw, 520px); }
.modal--sm { width: min(92vw, 400px); }
.modal--lg { width: min(94vw, 760px); }
.modal--xl { width: min(96vw, 960px); }

.modal__body > *:last-child { margin-bottom: 0; }
.modal__foot { row-gap: 0.45rem; }
.modal__foot .btn { min-height: 40px; }

/* 小屏：底部抽屉，按钮撑满、可换行，杜绝横向溢出 */
@media (max-width: 640px) {
  .modal { width: 100%; max-height: 92vh; }
  .modal--sm, .modal--lg, .modal--xl { width: 100%; }
  .modal__body { padding: 0.9rem 0.9rem 1rem; }
  .modal__head { padding: 0.8rem 0.6rem 0.8rem 0.95rem; }
  .modal__foot { padding: 0.7rem 0.9rem; }
  .modal__foot .btn { flex: 1 1 auto; min-width: 84px; }
  .modal__foot .spacer { flex: 0 0 0; }
}

/* ===================================================================
   时间轴管理列表
   =================================================================== */

.item--tl {
  align-items: flex-start;
  flex-wrap: wrap;
  row-gap: 0.45rem;
}
.item--tl .item__bar { align-self: stretch; min-height: 34px; }
.item--tl .item__main { flex: 1 1 190px; }
.item--tl .item__title { flex-wrap: wrap; white-space: normal; }
/* 中文标题不在字与字之间断行，只在标点/空格处换行；确实放不下时才任意断 */
.item--tl .item__name { word-break: keep-all; overflow-wrap: anywhere; }
/* 元信息按「片段」换行：只允许在片段之间断开，不会把「112 个事件」拆成两行 */
.item--tl .item__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  white-space: normal;
}
.item--tl .item__meta .mi { white-space: nowrap; }
.item--tl .item__meta .mi + .mi::before {
  content: '·';
  margin: 0 0.42rem;
  opacity: 0.65;
}
.item--tl .item__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  justify-content: flex-end;
  flex: 1 1 auto;
}

.act-pair { display: inline-flex; gap: 0.15rem; flex: 0 0 auto; }

.btn--icon {
  width: 34px;
  min-width: 34px;
  padding: 0;
  justify-content: center;
}
.btn--icon svg { width: 1.05em; height: 1.05em; }
.btn.is-disabled,
.btn.is-disabled:hover {
  opacity: 0.32;
  cursor: not-allowed;
  background: transparent;
}

@media (max-width: 640px) {
  .item--tl { flex-direction: column; align-items: stretch; }
  .item--tl .item__bar { width: 100%; height: 3px; min-height: 3px; border-radius: 2px; }
  /* 列方向下必须取消主轴 flex-basis，否则会被撑成 190px 的空白高度 */
  .item--tl .item__main { flex: 0 0 auto; }
  .item--tl .item__actions { justify-content: flex-start; }
  .item--tl .item__actions .btn { min-height: 32px; }
}

/* 主题色选择 */
.swatches { display: flex; flex-wrap: wrap; gap: 0.35rem; }
.swatch {
  width: 34px;
  height: 28px;
  border-radius: var(--radius-sm);
  border: 2px solid transparent;
  box-shadow: inset 0 0 0 1px var(--glass-border);
  cursor: pointer;
  padding: 0;
  transition: transform var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}
.swatch:hover { transform: translateY(-1px); }
.swatch.is-on { border-color: var(--text); transform: translateY(-1px); }
.swatch:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ===================================================================
   横向折叠控制面板（浮层，不遮挡画布，可实时观察）
   =================================================================== */

.fold-panel {
  position: fixed;
  z-index: 45;
  width: min(92vw, 360px);
  padding: 0.75rem;
  border-radius: var(--radius-lg);
  background: var(--glass-strong);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow);
  -webkit-backdrop-filter: blur(20px) saturate(150%);
  backdrop-filter: blur(20px) saturate(150%);
  animation: rise var(--dur) var(--ease);
}
.fold-panel__head {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  margin-bottom: 0.6rem;
}
.fold-panel__title {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.8125rem;
  font-weight: 650;
  flex: 1 1 auto;
}
.fold-panel__title svg { width: 15px; height: 15px; color: var(--accent); }
.fold-panel__x { width: 30px; height: 30px; min-height: 30px; min-width: 30px; padding: 0; }
.fold-panel__row { display: flex; align-items: center; gap: 0.4rem; }
.fold-panel__row .fp-btn { flex: 0 0 auto; min-width: 78px; }
.fold-panel__row .fp-btn svg { width: 1em; height: 1em; }
.fold-panel__row input[type="range"] {
  flex: 1 1 auto;
  min-width: 60px;
  min-height: 26px;
  padding: 0;
  border: 0;
  background: transparent;
  accent-color: var(--accent);
  height: 26px;
}
.fold-panel__now {
  margin-top: 0.5rem;
  font-size: 0.75rem;
  color: var(--text-dim);
  font-variant-numeric: tabular-nums;
}
.fold-panel__presets {
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem;
  margin-top: 0.5rem;
}
.fold-panel__presets .btn { min-height: 30px; padding: 0 0.5rem; font-size: 0.6875rem; }
.fp-full { width: 100%; margin-top: 0.5rem; min-height: 32px; }
.fold-panel__hint {
  margin-top: 0.55rem;
  font-size: 0.6875rem;
  line-height: 1.6;
  color: var(--text-faint);
}
.fold-panel__hint b { color: var(--text-dim); }

/* ===================================================================
   详情卡：查看态 / 内联编辑态
   =================================================================== */

.detail .pill--mini {
  height: 17px;
  font-size: 0.625rem;
  padding: 0 0.35rem;
  margin-left: 0.4rem;
  vertical-align: middle;
  background: var(--panel-2);
  color: var(--text-faint);
  font-weight: 600;
}
.detail__pills { display: flex; gap: 0.3rem; flex-wrap: wrap; margin-top: 0.4rem; }
.detail__meta {
  padding: 0 0.9rem 0.65rem;
  font-size: 0.6875rem;
  color: var(--text-faint);
  line-height: 1.6;
}
.detail__hintline {
  padding: 0 0.9rem 0.75rem;
  font-size: 0.6875rem;
  color: var(--text-dim);
  line-height: 1.6;
}
.detail__hintline--dim { color: var(--text-faint); padding-bottom: 0.8rem; }
.linkbtn {
  border: 0;
  background: transparent;
  color: var(--accent);
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  padding: 0 0.1rem;
  text-decoration: underline;
}
.linkbtn:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.detail--edit { max-height: 82vh; display: flex; flex-direction: column; }
.detail--edit .detail__head { flex: 0 0 auto; }
.detail__headrow { display: flex; align-items: center; gap: 0.4rem; flex-wrap: wrap; }
.detail__eyebrow {
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text-faint);
  text-transform: uppercase;
}
.detail__body--form {
  padding: 0.75rem 0.9rem;
  max-height: none;
  overflow: auto;
  flex: 1 1 auto;
  min-height: 0;
  color: var(--text);
}
.detail__body--form .field { margin-bottom: 0.7rem; }
.detail__body--form .row { grid-template-columns: 1fr; }
.detail--edit .detail__foot {
  flex: 0 0 auto;
  border-top: 1px solid var(--line-soft);
  padding: 0.6rem 0.7rem;
  flex-wrap: wrap;
}
.detail--edit .detail__foot .btn { flex: 0 0 auto; }
.detail--edit .detail__foot .spacer { flex: 1 1 auto; }

/* 标签编辑器 */
.tag-edit { display: flex; flex-wrap: wrap; gap: 0.3rem; margin-bottom: 0.35rem; }
.tagchip {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  height: 24px;
  padding: 0 0.3rem 0 0.5rem;
  border-radius: 999px;
  background: var(--panel-2);
  color: var(--text);
  font-size: 0.6875rem;
  font-weight: 550;
}
.tagchip--empty { background: transparent; color: var(--text-faint); padding: 0; font-weight: 400; }
.tagchip__x {
  border: 0;
  background: transparent;
  color: var(--text-dim);
  font-size: 0.9rem;
  line-height: 1;
  cursor: pointer;
  padding: 0 0.15rem;
  border-radius: 50%;
}
.tagchip__x:hover { color: var(--danger); }
.tag-add { display: flex; gap: 0.35rem; }
.tag-add input { flex: 1 1 auto; min-width: 0; }
.tag-add .btn { flex: 0 0 auto; }

@media (max-width: 640px) {
  .detail--edit { max-height: 78vh; }
  .detail--edit .detail__foot .btn { flex: 1 1 auto; min-width: 72px; }
  .detail--edit .detail__foot .spacer { flex: 0 0 0; }
}