:root {
  --bg: #ffffff;
  --card: #ffffff;
  --text: #1a1a1e;
  --muted: #8a8a93;
  --accent: #007aff;
  --border: #e8e8ee;
  --danger: #ff3b30;
  --ok: #34c759;
  --warn: #ff9500;
  --shadow: 0 2px 12px rgba(0,0,0,0.06);
}
* { margin: 0; padding: 0; box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html { overscroll-behavior-y: none; height: 100%; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  height: 100dvh;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: background .3s, color .3s;
}
.status-tint {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: env(safe-area-inset-top);
  background: #ffffff;
  z-index: 210;
  pointer-events: none;
}
#app {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  overflow-x: hidden;
  overscroll-behavior: contain;
  -webkit-overflow-scrolling: touch;
  padding: 0 16px calc(88px + env(safe-area-inset-bottom));
}
#nav {
  position: fixed;
  left: 0; right: 0; bottom: 0;
  display: flex;
  background: var(--card);
  border-top: 1px solid var(--border);
  padding: 5px 10px calc(7px + env(safe-area-inset-bottom));
  z-index: 100;
}
.nav-btn {
  flex: 1;
  background: none;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14.5px;
  font-weight: 600;
  color: var(--muted);
  cursor: pointer;
  padding: 10px 0;
  border-radius: 10px;
  transition: color .2s, transform .1s;
  font-family: inherit;
}
.nav-btn:active { transform: scale(.94); }
.nav-btn.active { color: var(--accent); font-weight: 700; }
.topbar {
  position: sticky;
  top: 0;
  background: var(--bg);
  z-index: 50;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 10px;
  padding: calc(14px + env(safe-area-inset-top)) 2px 10px;
}
.topbar::after {
  content: '';
  position: absolute;
  left: -16px;
  right: -16px;
  top: 100%;
  height: 26px;
  background: linear-gradient(var(--bg), transparent);
  pointer-events: none;
  z-index: 1;
}
.topbar h1 { font-size: 28px; font-weight: 800; letter-spacing: -0.6px; }
.topbar .sub { font-size: 13px; color: var(--muted); margin-top: 2px; }
.gear-btn {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  width: 38px; height: 38px;
  font-size: 16px;
  color: var(--text);
  cursor: pointer;
  flex-shrink: 0;
}
.back-btn {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 8px 14px 8px 10px;
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
  cursor: pointer;
  font-family: inherit;
  flex-shrink: 0;
}
.fab {
  position: fixed;
  bottom: calc(88px + env(safe-area-inset-bottom));
  right: 18px;
  width: 54px;
  height: 54px;
  border-radius: 27px;
  background: var(--accent);
  color: #fff;
  border: none;
  font-size: 26px;
  line-height: 1;
  box-shadow: 0 4px 20px rgba(0,122,255,0.4);
  cursor: pointer;
  z-index: 90;
  transition: transform .2s cubic-bezier(.34,1.56,.64,1);
}
.fab:active { transform: scale(.85) rotate(90deg); }
.fab.hidden { display: none; }
.section-label {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  padding: 16px 4px 8px;
}
.section-label.red { color: var(--danger); }
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 14px;
  box-shadow: var(--shadow);
  margin-bottom: 10px;
}
.tap { cursor: pointer; transition: transform .12s; }
.tap:active { transform: scale(.98); }
.list { display: flex; flex-direction: column; gap: 9px; }
.hw-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 13px;
  box-shadow: var(--shadow);
  display: flex;
  gap: 12px;
  align-items: center;
  animation: cardIn .3s cubic-bezier(.34,1.4,.64,1) backwards;
}
@keyframes cardIn {
  from { opacity: 0; transform: translateY(10px) scale(.97); }
  to { opacity: 1; transform: none; }
}
.hw-dot { width: 9px; height: 40px; border-radius: 6px; flex-shrink: 0; }
.hw-info { flex: 1; min-width: 0; }
.hw-title { font-size: 16px; font-weight: 600; margin-bottom: 4px; }
.hw-card.done-card .hw-title { color: var(--muted); text-decoration: line-through; }
.hw-meta { display: flex; gap: 6px; flex-wrap: wrap; align-items: center; }
.badge {
  font-size: 11.5px;
  font-weight: 700;
  padding: 3px 9px;
  border-radius: 10px;
  white-space: nowrap;
}
.badge.subject { background: #007aff22; }
.badge.late { background: rgba(255,59,48,.12); color: var(--danger); }
.badge.today { background: rgba(255,149,0,.14); color: var(--warn); }
.badge.soon { background: rgba(0,122,255,.09); color: var(--accent); }
.badge.st-todo { background: rgba(138,138,147,.13); color: var(--muted); }
.badge.st-progress { background: rgba(255,149,0,.14); color: var(--warn); }
.badge.st-done { background: rgba(52,199,89,.15); color: var(--ok); }
.badge.q-ok { background: rgba(52,199,89,.15); color: var(--ok); }
.badge.q-wrong { background: rgba(255,59,48,.12); color: var(--danger); }
.quick-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 9px; }
.quick-btn {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 15px 6px;
  box-shadow: var(--shadow);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: transform .12s;
  font-family: inherit;
}
.quick-btn:active { transform: scale(.96); }
.quick-btn .q-txt { font-size: 13.5px; font-weight: 700; color: var(--text); text-align: center; }
.progress-bar { height: 6px; border-radius: 4px; background: var(--border); overflow: hidden; margin-top: 10px; }
.progress-fill {
  height: 100%;
  border-radius: 4px;
  background: var(--accent);
  transition: width .5s cubic-bezier(.32,.72,.35,1);
}
.stat-row { display: flex; gap: 9px; margin-top: 14px; }
.stat {
  flex: 1;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 11px 6px;
  text-align: center;
  box-shadow: var(--shadow);
}
.stat b { display: block; font-size: 21px; letter-spacing: -0.4px; }
.stat span { font-size: 10.5px; font-weight: 700; color: var(--muted); text-transform: uppercase; letter-spacing: .04em; }
.stat.red b { color: var(--danger); }
.stat.orange b { color: var(--warn); }
.stat.green b { color: var(--ok); }
.class-chip-row { display: flex; flex-direction: column; gap: 8px; }
.class-chip {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 11px 14px;
  box-shadow: var(--shadow);
  display: flex;
  align-items: center;
  gap: 12px;
  animation: cardIn .3s ease backwards;
}
.class-chip .c-time { font-size: 13px; font-weight: 700; color: var(--accent); font-variant-numeric: tabular-nums; width: 92px; flex-shrink: 0; }
.class-chip .c-name { font-size: 15px; font-weight: 600; flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.class-chip .c-room { font-size: 12px; color: var(--muted); flex-shrink: 0; max-width: 40%; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.filter-tabs {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  padding: 10px 6px;
  margin: 0 -6px;
  scrollbar-width: none;
}
.filter-tabs::-webkit-scrollbar { display: none; }
.filter-tab {
  flex-shrink: 0;
  padding: 8px 16px;
  border-radius: 20px;
  background: var(--card);
  border: 1px solid var(--border);
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
  cursor: pointer;
  user-select: none;
  transition: all .25s cubic-bezier(.34,1.56,.64,1);
}
.filter-tab.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
  transform: scale(1.05);
}
.day-tab {
  flex: 1;
  min-width: 0;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 11px;
  padding: 9px 0;
  font-size: 13px;
  font-weight: 700;
  color: var(--muted);
  cursor: pointer;
  transition: all .2s;
  font-family: inherit;
  text-align: center;
}
.day-tab.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.filter-row { display: flex; gap: 8px; }
.upload-zone {
  border: 2px dashed var(--border);
  border-radius: 16px;
  padding: 24px 16px;
  text-align: center;
  color: var(--muted);
  background: var(--card);
  margin-bottom: 12px;
}
.upload-zone .u-ico { font-size: 32px; display: block; margin-bottom: 8px; }
.upload-zone .u-title { font-size: 15px; font-weight: 700; color: var(--text); margin-bottom: 3px; }
.upload-zone .u-sub { font-size: 12.5px; line-height: 1.5; }
.pick-btn {
  display: inline-block;
  margin-top: 12px;
  background: var(--accent);
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  padding: 10px 20px;
  border-radius: 12px;
  cursor: pointer;
}
.sheet-backdrop {
  position: fixed;
  top: env(safe-area-inset-top);
  left: 0; right: 0; bottom: 0;
  background: transparent;
  opacity: 0;
  pointer-events: none;
  transition: opacity .25s;
  z-index: 300;
}
.sheet-backdrop.open { opacity: 1; pointer-events: auto; }
.sheet {
  position: fixed;
  left: 0; right: 0; bottom: 0;
  background: #f2f2f6;
  border-radius: 22px 22px 0 0;
  padding: 12px 20px calc(30px + env(safe-area-inset-bottom));
  transform: translateY(105%);
  transition: transform .38s cubic-bezier(.32,.72,.35,1);
  z-index: 310;
  max-height: 92%;
  overflow-y: auto;
  overscroll-behavior: contain;
}
.sheet.open { transform: translateY(0); }
.sheet.dragging { transition: none; }
.sheet .grabber { width: 40px; height: 5px; border-radius: 3px; background: var(--muted); opacity: .4; margin: 0 auto 14px; cursor: grab; touch-action: none; }
.sheet h2 { font-size: 20px; font-weight: 700; margin-bottom: 16px; text-align: center; }
.field { margin-bottom: 13px; }
.field label { display: block; font-size: 12.5px; font-weight: 700; color: var(--muted); margin-bottom: 6px; }
.field input, .field select, .field textarea {
  width: 100%;
  padding: 12px 14px;
  font-size: 16px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--bg);
  color: var(--text);
  -webkit-appearance: none;
  appearance: none;
  font-family: inherit;
  transition: border-color .2s;
}
.field textarea { min-height: 70px; resize: vertical; }
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--accent); outline: none; }
.btn {
  width: 100%;
  padding: 14px;
  font-size: 16px;
  font-weight: 700;
  border: none;
  border-radius: 14px;
  background: var(--accent);
  color: #fff;
  cursor: pointer;
  margin-top: 6px;
  font-family: inherit;
  transition: transform .15s;
}
.btn:active { transform: scale(.97); }
.btn.secondary { background: var(--bg); color: var(--danger); }
.btn.mini {
  width: auto;
  padding: 8px 16px;
  font-size: 13px;
  border-radius: 11px;
  margin: 0;
}
.bulk-row {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 10px;
  margin-bottom: 9px;
}
.bulk-row-top { display: flex; gap: 8px; align-items: center; margin-bottom: 7px; }
.bulk-num {
  width: 25px; height: 25px;
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  font-size: 12px;
  font-weight: 800;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.bulk-row-top input {
  flex: 1;
  min-width: 0;
  padding: 9px 11px;
  font-size: 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--card);
  color: var(--text);
  font-family: inherit;
}
.bulk-del {
  margin-left: auto;
  background: rgba(255,59,48,.1);
  color: var(--danger);
  border: none;
  border-radius: 9px;
  width: 30px; height: 30px;
  font-size: 14px;
  cursor: pointer;
  flex-shrink: 0;
}
.divider { height: 1px; background: var(--border); margin: 16px 0; }
.small-note { font-size: 12px; color: var(--muted); line-height: 1.5; margin-top: 8px; }
.q-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 14px;
  box-shadow: var(--shadow);
  margin-bottom: 10px;
  animation: cardIn .3s ease backwards;
}
.q-card.correct { border-color: var(--ok); }
.q-card.wrong { border-color: var(--danger); }
.q-head { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; }
.q-num {
  min-width: 29px; height: 29px;
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  font-size: 13px;
  font-weight: 800;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.q-card.correct .q-num { background: var(--ok); }
.q-card.wrong .q-num { background: var(--danger); }
.q-text { font-size: 15px; line-height: 1.5; margin-bottom: 10px; white-space: pre-wrap; }
.q-answer-input {
  width: 100%;
  padding: 11px 13px;
  font-size: 15px;
  border: 1.5px solid var(--border);
  border-radius: 12px;
  background: var(--bg);
  color: var(--text);
  font-family: inherit;
}
.q-answer-input:focus { border-color: var(--accent); outline: none; }
.q-actions { display: flex; gap: 8px; margin-top: 10px; }
.q-feedback { font-size: 13.5px; line-height: 1.5; margin-top: 10px; padding: 10px 12px; border-radius: 12px; }
.q-feedback.ok { background: rgba(52,199,89,.11); color: var(--ok); font-weight: 600; }
.q-feedback.no { background: rgba(255,59,48,.09); color: var(--danger); }
.q-feedback.hint { background: rgba(255,149,0,.11); color: #c77700; }
.remind-banner {
  background: var(--card);
  border: 1px solid var(--border);
  border-left: 4px solid var(--danger);
  border-radius: 14px;
  padding: 12px 15px;
  margin-bottom: 12px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--danger);
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
}
.busy {
  position: fixed;
  inset: 0;
  background: rgba(255,255,255,0.65);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 500;
}
.busy.on { display: flex; }
.busy-box {
  background: var(--card);
  border-radius: 18px;
  padding: 20px 28px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  font-size: 13.5px;
  font-weight: 600;
}
.spinner {
  width: 28px; height: 28px;
  border: 3.5px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.toast {
  position: fixed;
  bottom: calc(92px + env(safe-area-inset-bottom));
  left: 50%;
  transform: translateX(-50%) translateY(16px);
  background: var(--text);
  color: var(--bg);
  font-size: 13.5px;
  font-weight: 600;
  padding: 11px 20px;
  border-radius: 20px;
  opacity: 0;
  pointer-events: none;
  transition: all .3s cubic-bezier(.34,1.4,.64,1);
  z-index: 600;
  max-width: 86vw;
  text-align: center;
}
.toast.on { opacity: 1; transform: translateX(-50%) translateY(0); }
.edit-form-title {
  font-size: 12px;
  font-weight: 800;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: .07em;
  padding: 16px 4px 10px;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }