:root {
  --bg: #f4f6f8;
  --card: #fff;
  --ink: #1a1d21;
  --muted: #6b7280;
  --line: #d8dee6;
  --income: #dbeafe;
  --sum: #bbf7d0;
  --spend: #fde68a;
  --remain: #86efac;
  --error: #b91c1c;
  font-family: "Segoe UI", "PT Root UI", system-ui, sans-serif;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
}
.login-page {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 1rem;
}
.login-card {
  width: min(22rem, 100%);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1.5rem;
}
.login-card h1 { margin: 0 0 0.25rem; font-size: 1.35rem; }
.muted { color: var(--muted); margin: 0 0 1rem; }
.error { color: var(--error); }
label { display: block; margin: 0.75rem 0 0.25rem; font-size: 0.9rem; }
input {
  width: 100%;
  padding: 0.55rem 0.65rem;
  border: 1px solid var(--line);
  border-radius: 8px;
  font: inherit;
}
.primary-btn, .ghost-btn {
  margin-top: 1rem;
  font: inherit;
  cursor: pointer;
  border-radius: 8px;
  padding: 0.55rem 0.9rem;
}
.primary-btn {
  width: 100%;
  border: 0;
  background: #111827;
  color: #fff;
}
.ghost-btn {
  border: 1px solid var(--line);
  background: transparent;
}
.status { font-weight: 600; }
.top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem 1rem;
  background: var(--card);
  border-bottom: 1px solid var(--line);
}
.brand { font-weight: 700; letter-spacing: 0.02em; }
.sheet-wrap { padding: 1rem; overflow-x: auto; }
.month-grid {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(14rem, 1fr);
  gap: 0.75rem;
  min-width: max-content;
}
.month-col {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
  padding-bottom: 0.5rem;
}
.month-col h2 {
  margin: 0;
  padding: 0.55rem 0.65rem;
  font-size: 0.95rem;
  border-bottom: 1px solid var(--line);
}
.sec-head {
  margin: 0.45rem 0 0;
  padding: 0.35rem 0.65rem;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
  background: #f8fafc;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.sec-head.total-head { color: #065f46; background: #ecfdf5; }
.month-col table { width: 100%; border-collapse: collapse; font-size: 0.82rem; }
.month-col th, .month-col td {
  padding: 0.2rem 0.4rem;
  border-bottom: 1px solid #eef2f6;
  text-align: left;
  font-weight: 500;
  vertical-align: middle;
}
.month-col td { text-align: right; font-variant-numeric: tabular-nums; white-space: nowrap; }
.month-col tr.income th,
.month-col tr.expense th { background: var(--income); }
.month-col tr.expense th { background: #fff7ed; }
.month-col tr.sum th, .month-col tr.sum td { background: var(--sum); font-weight: 700; }
.month-col tr.spend th, .month-col tr.spend td,
.month-col tr.balance th, .month-col tr.balance td { background: var(--spend); font-weight: 700; }
.month-col tr.remain th, .month-col tr.remain td { background: var(--remain); font-weight: 700; }
.month-col th { display: flex; align-items: center; gap: 0.25rem; }
.label-inp, .due-inp, .amt-inp {
  border: 1px solid transparent;
  background: transparent;
  border-radius: 4px;
  font: inherit;
  padding: 0.15rem 0.25rem;
  min-width: 0;
}
.label-inp { flex: 1; width: 100%; }
.due-inp { width: 2rem; flex: 0 0 auto; color: var(--muted); font-size: 0.75rem; text-align: center; }
.amt-inp { width: 6.5rem; text-align: right; font-variant-numeric: tabular-nums; }
.label-inp:focus, .due-inp:focus, .amt-inp:focus {
  outline: none;
  border-color: #93c5fd;
  background: #fff;
}
.add-row {
  display: block;
  width: calc(100% - 0.8rem);
  margin: 0.35rem 0.4rem 0;
  border: 1px dashed var(--line);
  background: transparent;
  border-radius: 6px;
  padding: 0.3rem;
  font: inherit;
  font-size: 0.78rem;
  color: var(--muted);
  cursor: pointer;
}
.add-row:hover { border-color: #94a3b8; color: var(--ink); }
.row-del {
  flex: 0 0 auto;
  border: 0;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 1rem;
  line-height: 1;
  padding: 0 0.15rem;
}
.row-del:hover { color: var(--error); }
.top .ghost-btn { margin-top: 0; }