:root {
  --bg: #0f1115; --card: #181b22; --card2: #1f232c; --text: #eef0f4; --muted: #8b93a3;
  --border: #2a2f3a; --accent: #f5b04c; --accent-text: #1a1200; --green: #3ecf8e; --red: #ff6b6b;
  --radius: 14px;
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--bg); color: var(--text); font: 16px/1.45 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; -webkit-font-smoothing: antialiased; }
main { max-width: 820px; margin: 0 auto; padding: 16px 16px calc(32px + env(safe-area-inset-bottom)); }
.hidden { display: none !important; }
h1 { font-size: 1.4rem; margin: 0; }
h2 { font-size: 1.1rem; margin: 0 0 10px; }
.muted { color: var(--muted); }
.small-text { font-size: .85rem; text-align: center; margin-top: 24px; }
.error { color: var(--red); min-height: 1.2em; margin: 6px 0 0; font-size: .9rem; }

.top { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 16px; flex-wrap: wrap; }
.who { display: flex; align-items: center; gap: 8px; font-size: .9rem; color: var(--muted); }

.card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 12px; margin-bottom: 16px; }
.person { display: flex; flex-direction: column; gap: 8px; }
.person .name { display: flex; justify-content: space-between; align-items: baseline; }
.person .name strong { font-size: 1.15rem; }
.person .name .id { font-size: .75rem; color: var(--muted); font-variant-numeric: tabular-nums; }
.person .balance { font-size: 2rem; font-weight: 700; letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.person .meta { display: flex; gap: 14px; color: var(--muted); font-size: .9rem; flex-wrap: wrap; }
.person .meta b { color: var(--text); font-weight: 600; }
.person .actions { display: flex; gap: 8px; margin-top: 4px; }
.person .actions .btn { flex: 1; }

.btn { appearance: none; border: 1px solid var(--border); background: var(--card2); color: var(--text); border-radius: 10px; padding: 10px 14px; font-size: .95rem; font-weight: 600; cursor: pointer; transition: transform .05s, background .15s; }
.btn:active { transform: scale(.98); }
.btn.primary { background: var(--accent); color: var(--accent-text); border-color: transparent; }
.btn.add { background: rgba(62,207,142,.15); border-color: rgba(62,207,142,.4); color: var(--green); }
.btn.sub { background: rgba(255,107,107,.15); border-color: rgba(255,107,107,.4); color: var(--red); }
.btn.small { padding: 6px 10px; font-size: .85rem; }
.btn.ghost { background: transparent; }
.btn:disabled { opacity: .5; cursor: not-allowed; }
.link { background: none; border: none; color: var(--accent); cursor: pointer; font: inherit; padding: 0; }

select, input[type=text], input[type=number], input[type=password] {
  width: 100%; background: var(--card2); color: var(--text); border: 1px solid var(--border); border-radius: 10px; padding: 10px 12px; font-size: 1rem; outline: none;
}
select { width: auto; }
input:focus, select:focus { border-color: var(--accent); }
label { display: block; font-size: .9rem; color: var(--muted); margin: 10px 0 0; }
label input { margin-top: 4px; }

.section-head { display: flex; justify-content: space-between; align-items: center; gap: 8px; flex-wrap: wrap; margin-bottom: 8px; }
.filters { display: flex; gap: 8px; align-items: center; }

.history { display: flex; flex-direction: column; }
.h-row { display: grid; grid-template-columns: auto 1fr auto; gap: 10px 12px; padding: 10px 0; border-top: 1px solid var(--border); align-items: center; }
.h-row:first-child { border-top: none; }
.h-amt { font-weight: 700; font-variant-numeric: tabular-nums; white-space: nowrap; min-width: 92px; text-align: right; }
.h-amt.add { color: var(--green); }
.h-amt.subtract { color: var(--red); }
.h-amt.other { color: var(--muted); font-weight: 500; }
.h-main { min-width: 0; }
.h-main .h-who { font-weight: 600; }
.h-main .h-note { color: var(--muted); font-size: .9rem; overflow-wrap: anywhere; }
.h-side { text-align: right; font-size: .8rem; color: var(--muted); white-space: nowrap; }
.h-side .after { font-variant-numeric: tabular-nums; color: var(--text); }
.h-row.undone { opacity: .5; }
.h-row.undone .h-amt { text-decoration: line-through; }
.empty { color: var(--muted); padding: 16px 0; text-align: center; }

.modal, .login { position: fixed; inset: 0; background: rgba(0,0,0,.6); display: flex; align-items: center; justify-content: center; padding: 16px; z-index: 10; }
.modal-card, .login-card { width: 100%; max-width: 420px; }
.login-card h1 { margin-bottom: 4px; }
.login-card input { margin: 12px 0; }
.login-card .btn { width: 100%; }
.row { display: flex; gap: 8px; margin-top: 14px; }
.row .btn { flex: 1; }
.seg { flex: 1; margin: 0; }
.seg input { display: none; }
.seg span { display: block; text-align: center; padding: 10px; border: 1px solid var(--border); border-radius: 10px; background: var(--card2); font-weight: 600; cursor: pointer; color: var(--text); }
.seg input:checked + span { border-color: var(--accent); background: rgba(245,176,76,.15); color: var(--accent); }
.seg input[value=subtract]:checked + span { border-color: var(--red); background: rgba(255,107,107,.15); color: var(--red); }

.toast { position: fixed; left: 50%; bottom: calc(20px + env(safe-area-inset-bottom)); transform: translateX(-50%); background: var(--card2); border: 1px solid var(--border); padding: 10px 16px; border-radius: 10px; font-size: .9rem; z-index: 20; box-shadow: 0 6px 20px rgba(0,0,0,.4); }

@media (max-width: 520px) {
  .h-row { grid-template-columns: auto 1fr; }
  .h-side { grid-column: 1 / -1; text-align: left; display: flex; gap: 10px; justify-content: space-between; }
}