:root {
  color-scheme: light;
  --bg: #f4f6f8;
  --surface: #ffffff;
  --surface-2: #eef2f6;
  --text: #17202a;
  --muted: #68727d;
  --border: #dfe4e9;
  --blue: #1677ff;
  --blue-soft: #e8f1ff;
  --green: #138a56;
  --green-soft: #e5f6ee;
  --amber: #b35c00;
  --amber-soft: #fff0df;
  --red: #c43e3e;
  --red-soft: #fdecec;
  --purple: #7652b5;
  --shadow: 0 12px 32px rgba(20, 32, 48, .12);
}

[data-theme="dark"] {
  color-scheme: dark;
  --bg: #141719;
  --surface: #1d2125;
  --surface-2: #252b30;
  --text: #edf1f4;
  --muted: #a4adb5;
  --border: #343b42;
  --blue: #6aa7ff;
  --blue-soft: #233650;
  --green: #54c18a;
  --green-soft: #1d3a2d;
  --amber: #f0a34f;
  --amber-soft: #432e1b;
  --red: #ff7a7a;
  --red-soft: #482727;
  --purple: #b49ae0;
  --shadow: 0 16px 38px rgba(0, 0, 0, .28);
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
html, body { min-height: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font: 14px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; letter-spacing: 0; }
button, input, select, textarea { font: inherit; letter-spacing: 0; }
button { cursor: pointer; }
button:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible { outline: 3px solid color-mix(in srgb, var(--blue) 28%, transparent); outline-offset: 1px; }

.app-shell { min-height: 100vh; }
.topbar { min-height: 68px; display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 12px clamp(16px, 4vw, 42px); background: var(--surface); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 20; }
.brand { display: flex; align-items: center; gap: 10px; min-width: 0; }
.brand img { border-radius: 8px; }
.brand h1 { margin: 0; font-size: 18px; line-height: 1.2; }
.brand p { margin: 2px 0 0; color: var(--muted); font-size: 12px; }
.dot { display: inline-block; width: 7px; height: 7px; margin-right: 6px; border-radius: 50%; background: var(--amber); }
.dot.ok { background: var(--green); }
.dot.error { background: var(--red); }
.top-actions { display: flex; align-items: center; gap: 8px; }
.icon-button { width: 36px; height: 36px; display: inline-grid; place-items: center; border: 1px solid var(--border); border-radius: 7px; background: var(--surface); color: var(--text); font-size: 20px; line-height: 1; }
.icon-button:hover { background: var(--surface-2); }
.primary, .danger, .drawer-actions button, .dialog-actions button { min-height: 38px; border: 1px solid var(--border); border-radius: 7px; padding: 7px 14px; background: var(--surface); color: var(--text); font-weight: 600; }
.primary { border-color: var(--blue); background: var(--blue); color: white; }
.danger { border-color: var(--red); color: var(--red); background: transparent; }
.add-button { display: flex; align-items: center; gap: 4px; }

main { padding: 20px clamp(14px, 4vw, 42px) 48px; max-width: 1680px; margin: 0 auto; }
.stats { display: grid; grid-template-columns: repeat(5, minmax(120px, 1fr)); border: 1px solid var(--border); background: var(--surface); }
.stat { min-height: 88px; padding: 14px 16px; border-right: 1px solid var(--border); }
.stat:last-child { border-right: 0; }
.stat strong { display: block; font-size: 25px; line-height: 1.1; }
.stat span { color: var(--muted); font-size: 12px; }
.stat.overdue strong { color: var(--red); }
.stat.done strong { color: var(--green); }

.workbar { margin-top: 16px; display: flex; align-items: center; justify-content: space-between; gap: 12px; border-bottom: 1px solid var(--border); }
.tabs { display: flex; align-self: stretch; overflow-x: auto; }
.tabs button { min-width: 70px; padding: 12px 14px; border: 0; border-bottom: 2px solid transparent; background: transparent; color: var(--muted); }
.tabs button.active { color: var(--blue); border-bottom-color: var(--blue); font-weight: 700; }
.filters { display: flex; gap: 8px; padding-bottom: 8px; }
.filters input, .filters select { height: 36px; border: 1px solid var(--border); border-radius: 6px; background: var(--surface); color: var(--text); padding: 0 10px; }
.filters input { width: min(250px, 24vw); }

.view { margin-top: 16px; min-height: 400px; }
.board { display: grid; grid-template-columns: repeat(3, minmax(240px, 1fr)); gap: 12px; align-items: start; }
.column { min-width: 0; background: var(--surface-2); border-top: 3px solid var(--blue); }
.column[data-status="进行中"] { border-top-color: var(--amber); }
.column[data-status="已完成"] { border-top-color: var(--green); }
.column-head { display: flex; align-items: center; justify-content: space-between; padding: 12px; font-weight: 700; }
.column-head span { color: var(--muted); font-weight: 500; }
.task-stack { display: grid; gap: 8px; padding: 0 8px 8px; min-height: 80px; }
.task-card { width: 100%; text-align: left; border: 1px solid var(--border); border-radius: 7px; background: var(--surface); color: var(--text); padding: 12px; box-shadow: 0 1px 2px rgba(15, 23, 42, .05); }
.task-card:hover { border-color: var(--blue); }
.task-card.done .task-title { text-decoration: line-through; color: var(--muted); }
.task-card.overdue { border-left: 3px solid var(--red); }
.task-title { font-weight: 650; overflow-wrap: anywhere; }
.task-meta { display: flex; align-items: center; flex-wrap: wrap; gap: 5px; margin-top: 10px; }
.tag { border-radius: 4px; padding: 2px 6px; font-size: 11px; color: var(--muted); background: var(--surface-2); }
.tag.high { color: var(--red); background: var(--red-soft); }
.tag.medium { color: var(--amber); background: var(--amber-soft); }
.tag.low { color: var(--green); background: var(--green-soft); }
.tag.due { color: var(--blue); background: var(--blue-soft); }

.task-table { width: 100%; border-collapse: collapse; background: var(--surface); border: 1px solid var(--border); }
.task-table th, .task-table td { padding: 11px 12px; border-bottom: 1px solid var(--border); text-align: left; vertical-align: middle; }
.task-table th { color: var(--muted); font-size: 12px; background: var(--surface-2); }
.task-table tr[data-id] { cursor: pointer; }
.task-table tr[data-id]:hover { background: var(--blue-soft); }

.calendar-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 10px; }
.calendar-head div { display: flex; gap: 6px; }
.calendar-grid { display: grid; grid-template-columns: repeat(7, minmax(90px, 1fr)); border-top: 1px solid var(--border); border-left: 1px solid var(--border); background: var(--surface); }
.weekday, .calendar-day { border-right: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.weekday { padding: 8px; color: var(--muted); font-size: 12px; text-align: center; background: var(--surface-2); }
.calendar-day { min-height: 118px; padding: 7px; min-width: 0; }
.calendar-day.outside { color: var(--muted); background: color-mix(in srgb, var(--surface-2) 55%, transparent); }
.calendar-day.today { box-shadow: inset 0 0 0 2px var(--blue); }
.day-number { font-size: 12px; font-weight: 700; }
.calendar-task { display: block; width: 100%; margin-top: 5px; border: 0; border-radius: 4px; padding: 4px 5px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; text-align: left; color: var(--text); background: var(--blue-soft); font-size: 11px; }

.empty { min-height: 260px; display: grid; place-items: center; color: var(--muted); border: 1px dashed var(--border); }
.skeleton { height: 86px; margin-bottom: 8px; background: linear-gradient(90deg, var(--surface-2), var(--surface), var(--surface-2)); background-size: 200% 100%; animation: shimmer 1.1s infinite; }
@keyframes shimmer { to { background-position: -200% 0; } }

.backdrop { position: fixed; inset: 0; z-index: 39; background: rgba(9, 16, 24, .45); }
.drawer { position: fixed; z-index: 40; top: 0; right: 0; width: min(520px, 100vw); height: 100dvh; overflow: auto; background: var(--surface); box-shadow: var(--shadow); transform: translateX(105%); transition: transform .2s ease; padding-bottom: env(safe-area-inset-bottom); }
.drawer.open { transform: translateX(0); }
.drawer > header { min-height: 68px; display: flex; align-items: center; justify-content: space-between; padding: 12px 18px; border-bottom: 1px solid var(--border); }
.drawer h2, .drawer p { margin: 0; }
.drawer h2 { font-size: 18px; }
.drawer p { color: var(--muted); font-size: 11px; }
.drawer form { padding: 18px; display: grid; gap: 15px; }
.drawer label { display: grid; gap: 6px; color: var(--muted); font-size: 12px; }
.drawer input, .drawer select, .drawer textarea { width: 100%; border: 1px solid var(--border); border-radius: 6px; background: var(--surface); color: var(--text); padding: 9px 10px; font-size: 14px; }
.drawer textarea { resize: vertical; }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.drawer-actions { display: flex; justify-content: flex-end; gap: 8px; padding-top: 8px; }
.drawer-actions .danger { margin-right: auto; }
.history { border-top: 1px solid var(--border); padding: 16px 18px; }
.history h3 { margin: 0 0 8px; font-size: 14px; }
.history ol { margin: 0; padding-left: 22px; color: var(--muted); font-size: 12px; }
.history li { margin: 7px 0; }

dialog { max-width: 420px; border: 1px solid var(--border); border-radius: 8px; background: var(--surface); color: var(--text); box-shadow: var(--shadow); }
dialog::backdrop { background: rgba(9, 16, 24, .5); }
dialog h2 { margin: 0; font-size: 18px; }
dialog p { color: var(--muted); }
.dialog-actions { display: flex; justify-content: flex-end; gap: 8px; }

.toast { position: fixed; z-index: 60; left: 50%; bottom: max(22px, env(safe-area-inset-bottom)); transform: translate(-50%, 30px); opacity: 0; pointer-events: none; border-radius: 7px; background: #17202a; color: white; padding: 9px 14px; box-shadow: var(--shadow); transition: .18s ease; }
.toast.show { opacity: 1; transform: translate(-50%, 0); }

.login-screen { min-height: 100dvh; display: grid; place-items: center; padding: 24px; }
.login-panel { width: min(360px, 100%); display: grid; gap: 13px; padding: 28px; background: var(--surface); border: 1px solid var(--border); box-shadow: var(--shadow); }
.login-panel img { border-radius: 8px; }
.login-panel h1 { margin: 0; font-size: 24px; }
.login-panel label { color: var(--muted); font-size: 12px; }
.login-panel input { width: 100%; height: 42px; margin-top: 5px; border: 1px solid var(--border); border-radius: 6px; padding: 0 10px; background: var(--surface); color: var(--text); }
.wide { width: 100%; }
.form-error { min-height: 20px; margin: 0; color: var(--red); font-size: 12px; }

@media (max-width: 900px) {
  .stats { grid-template-columns: repeat(3, 1fr); }
  .stat:nth-child(3) { border-right: 0; }
  .stat:nth-child(n+4) { border-top: 1px solid var(--border); }
  .board { grid-template-columns: 1fr; }
  .column { display: grid; grid-template-columns: 132px 1fr; }
  .column-head { align-items: start; }
  .task-stack { padding-top: 8px; }
  .calendar-grid { min-width: 760px; }
  .view:has(.calendar-grid) { overflow-x: auto; }
}

@media (max-width: 640px) {
  .topbar { padding: 10px 12px; }
  .brand p { max-width: 150px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
  .top-actions { gap: 5px; }
  .top-actions .icon-button { width: 34px; height: 34px; }
  .add-button span:last-child { display: none; }
  main { padding: 12px 10px 32px; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .stat { min-height: 76px; }
  .stat:nth-child(2) { border-right: 0; }
  .stat:nth-child(3) { border-right: 1px solid var(--border); border-top: 1px solid var(--border); }
  .stat:nth-child(4) { border-right: 0; }
  .stat:last-child { grid-column: 1 / -1; border-top: 1px solid var(--border); }
  .workbar { display: block; }
  .tabs button { min-width: 78px; }
  .filters { padding: 8px 0; overflow-x: auto; }
  .filters input { width: 160px; flex: 0 0 auto; }
  .filters select { flex: 0 0 auto; }
  .column { display: block; }
  .task-table th:nth-child(3), .task-table td:nth-child(3), .task-table th:nth-child(5), .task-table td:nth-child(5) { display: none; }
  .task-table th, .task-table td { padding: 10px 8px; }
  .form-grid { grid-template-columns: 1fr; }
}