/* ==========================================================================
   Trackxpense — prototype stylesheet
   Reusable in real development. Mobile-first. System fonts only.
   ========================================================================== */

:root{
  --paper:#faf8f3;
  --panel:#ffffff;
  --ink:#1c1a17;
  --ink-soft:#55504a;
  --ink-faint:#8a837a;
  --line:#e7e1d6;
  --line-soft:#f0ebe1;
  --upi:#0a7d4d;          /* settle / confirmed / UPI / owed-to-you */
  --upi-bg:#e7f4ec;
  --upi-dark:#075c39;
  --owe:#b5411f;          /* debt / you owe */
  --owe-bg:#fbeae3;
  --hold:#9a6b00;         /* pending */
  --hold-bg:#fbf1d8;
  --blue:#2358c9;
  --radius:14px;
  --radius-sm:10px;
  --shadow:0 1px 2px rgba(28,26,23,.06),0 2px 8px rgba(28,26,23,.04);
  --shadow-lg:0 8px 30px rgba(28,26,23,.14);
  --maxw:460px;           /* phone-frame width */
  --header-h:56px;
  --nav-h:60px;
}

*{box-sizing:border-box}
html{ -webkit-text-size-adjust:100%; }
body{
  margin:0;
  background:#efe9dd;
  color:var(--ink);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  line-height:1.5;
  font-size:15px;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
button{font-family:inherit}
input,select,textarea{font-family:inherit;font-size:16px} /* 16px stops iOS zoom */

/* --------------------------------------------------------------------------
   Prototype banner (shown to stakeholders)
   -------------------------------------------------------------------------- */
.proto-banner{
  position:fixed;top:0;left:0;right:0;z-index:200;
  background:var(--hold-bg);color:var(--hold);
  font-size:12px;font-weight:600;text-align:center;
  padding:5px 12px;border-bottom:1px solid #e8d9a8;
  letter-spacing:.01em;
}
.proto-banner b{font-weight:800}
.has-banner{--banner-h:27px}

/* --------------------------------------------------------------------------
   Phone frame — centers the app on desktop, full-bleed on real phones
   -------------------------------------------------------------------------- */
.device{
  max-width:var(--maxw);
  margin:0 auto;
  min-height:100vh;
  background:var(--paper);
  position:relative;
  box-shadow:var(--shadow-lg);
  display:flex;flex-direction:column;
}
@media(min-width:520px){
  body.has-banner .device{margin-top:27px}
}

/* --------------------------------------------------------------------------
   App header
   -------------------------------------------------------------------------- */
.appbar{
  position:sticky;top:0;z-index:50;
  height:var(--header-h);
  display:flex;align-items:center;gap:10px;
  padding:0 14px;
  background:var(--paper);
  border-bottom:1px solid var(--line);
}
body.has-banner .appbar{top:27px}
.appbar .back{
  width:36px;height:36px;border-radius:9px;border:none;background:transparent;
  display:flex;align-items:center;justify-content:center;cursor:pointer;
  color:var(--ink);font-size:20px;margin-left:-6px;
}
.appbar .back:active{background:var(--line-soft)}
.appbar h1{font-size:17px;font-weight:700;margin:0;flex:1;letter-spacing:-.01em;
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.appbar .bar-action{
  border:none;background:transparent;color:var(--upi);font-weight:700;
  font-size:14px;cursor:pointer;padding:8px;border-radius:8px;
}
.appbar .bar-action:active{background:var(--upi-bg)}
.appbar .brand{font-weight:800;font-size:18px;letter-spacing:-.02em}
.appbar .brand .k{color:var(--upi)}

/* --------------------------------------------------------------------------
   Scroll area + bottom nav
   -------------------------------------------------------------------------- */
.screen{
  flex:1;
  padding:16px 16px calc(var(--nav-h) + 20px);
  overflow-y:auto;
}
.screen.no-nav{padding-bottom:24px}

.tabbar{
  position:fixed;bottom:0;left:50%;transform:translateX(-50%);
  width:100%;max-width:var(--maxw);
  height:var(--nav-h);
  background:var(--panel);
  border-top:1px solid var(--line);
  display:flex;z-index:60;
  padding-bottom:env(safe-area-inset-bottom);
}
.tabbar a{
  flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;
  gap:3px;color:var(--ink-faint);font-size:11px;font-weight:600;
}
.tabbar a .ic{font-size:19px;line-height:1}
.tabbar a.active{color:var(--upi)}

/* --------------------------------------------------------------------------
   Typography helpers
   -------------------------------------------------------------------------- */
.h-sec{font-size:12px;font-weight:700;color:var(--ink-faint);
  letter-spacing:.04em;text-transform:uppercase;margin:22px 2px 10px}
.h-sec:first-child{margin-top:6px}
.muted{color:var(--ink-soft)}
.faint{color:var(--ink-faint)}
.num{font-variant-numeric:tabular-nums}
.pos{color:var(--upi);font-weight:700}
.neg{color:var(--owe);font-weight:700}
.center{text-align:center}
.rupee{font-variant-numeric:tabular-nums;font-weight:700}

/* --------------------------------------------------------------------------
   Cards & list rows
   -------------------------------------------------------------------------- */
.card{
  background:var(--panel);border:1px solid var(--line);
  border-radius:var(--radius);box-shadow:var(--shadow);
  overflow:hidden;
}
.card + .card{margin-top:12px}
.pad{padding:16px}

.row{
  display:flex;align-items:center;gap:12px;
  padding:14px 16px;background:var(--panel);
  border-bottom:1px solid var(--line-soft);cursor:pointer;
}
.row:last-child{border-bottom:none}
.row:active{background:var(--line-soft)}
.row .grow{flex:1;min-width:0}
.row .r-title{font-weight:600;font-size:15px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.row .r-sub{font-size:13px;color:var(--ink-faint);margin-top:1px}
.row .r-right{text-align:right;white-space:nowrap}
.row .r-amt{font-weight:700;font-variant-numeric:tabular-nums}
.row .chev{color:var(--line);font-size:18px}

/* Avatar (initials, pure CSS — no images) */
.av{
  width:42px;height:42px;border-radius:50%;flex:none;
  display:flex;align-items:center;justify-content:center;
  font-weight:700;font-size:15px;color:#fff;letter-spacing:.02em;
}
.av.sm{width:32px;height:32px;font-size:12px}
.av.lg{width:60px;height:60px;font-size:22px}
.av-c0{background:#0a7d4d}.av-c1{background:#2358c9}.av-c2{background:#b5411f}
.av-c3{background:#7a4bbf}.av-c4{background:#c1820a}.av-c5{background:#0e8f9c}
.av-stack{display:flex}
.av-stack .av{margin-left:-10px;border:2px solid var(--panel)}
.av-stack .av:first-child{margin-left:0}

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  border:none;border-radius:var(--radius-sm);cursor:pointer;
  font-weight:700;font-size:15px;padding:13px 18px;width:100%;
  transition:transform .05s;
}
.btn:active{transform:scale(.985)}
.btn-primary{background:var(--upi);color:#fff}
.btn-primary:active{background:var(--upi-dark)}
.btn-dark{background:var(--ink);color:#f4f1ea}
.btn-ghost{background:var(--panel);color:var(--ink);border:1px solid var(--line)}
.btn-danger{background:var(--owe-bg);color:var(--owe)}
.btn-upi{background:#5f259f;color:#fff} /* UPI purple */
.btn-sm{width:auto;padding:9px 14px;font-size:13px;border-radius:9px}
.btn-row{display:flex;gap:10px}
.btn-row .btn{width:auto;flex:1}

.fab{
  position:fixed;bottom:calc(var(--nav-h) + 16px);left:50%;
  transform:translateX(calc(var(--maxw)/2 - 100%  - 16px + 0px));
  z-index:65;
}
@media(max-width:491px){
  .fab{transform:none;right:16px;left:auto}
}
.fab button{
  background:var(--upi);color:#fff;border:none;border-radius:999px;
  height:52px;padding:0 22px;font-weight:800;font-size:15px;cursor:pointer;
  box-shadow:0 6px 18px rgba(10,125,77,.42);display:flex;align-items:center;gap:8px;
}
.fab button:active{background:var(--upi-dark)}

/* --------------------------------------------------------------------------
   Badges / pills
   -------------------------------------------------------------------------- */
.pill{display:inline-flex;align-items:center;gap:5px;
  font-size:12px;font-weight:700;padding:3px 9px;border-radius:999px;white-space:nowrap}
.pill-pos{background:var(--upi-bg);color:var(--upi)}
.pill-neg{background:var(--owe-bg);color:var(--owe)}
.pill-hold{background:var(--hold-bg);color:var(--hold)}
.pill-neutral{background:var(--line-soft);color:var(--ink-soft)}
.pill .dot{width:6px;height:6px;border-radius:50%;background:currentColor}

.chip{
  display:inline-flex;align-items:center;gap:6px;
  border:1px solid var(--line);background:var(--panel);border-radius:999px;
  padding:7px 13px;font-size:13px;font-weight:600;cursor:pointer;color:var(--ink-soft);
}
.chip.on{background:var(--upi);color:#fff;border-color:var(--upi)}
.chip-wrap{display:flex;gap:8px;flex-wrap:wrap}

/* --------------------------------------------------------------------------
   Forms
   -------------------------------------------------------------------------- */
.field{margin-bottom:16px}
.field label{display:block;font-size:13px;font-weight:600;color:var(--ink-soft);margin-bottom:6px}
.input,select.input,textarea.input{
  width:100%;border:1px solid var(--line);border-radius:var(--radius-sm);
  padding:13px 14px;background:var(--panel);color:var(--ink);
  outline:none;transition:border-color .12s,box-shadow .12s;
}
.input:focus{border-color:var(--upi);box-shadow:0 0 0 3px var(--upi-bg)}
.input-amount{
  font-size:30px;font-weight:800;text-align:center;letter-spacing:-.01em;
  padding:16px;font-variant-numeric:tabular-nums;
}
.input-lead{position:relative}
.input-lead .lead{position:absolute;left:14px;top:50%;transform:translateY(-50%);
  color:var(--ink-faint);font-weight:700}
.input-lead .input{padding-left:30px}
.help{font-size:12px;color:var(--ink-faint);margin-top:6px}
.help.err{color:var(--owe);font-weight:600}
.seg{display:flex;background:var(--line-soft);border-radius:11px;padding:4px;gap:4px}
.seg button{
  flex:1;border:none;background:transparent;border-radius:8px;
  padding:9px 6px;font-weight:700;font-size:13px;color:var(--ink-soft);cursor:pointer;
}
.seg button.on{background:var(--panel);color:var(--ink);box-shadow:var(--shadow)}

/* Split participant row */
.split-row{display:flex;align-items:center;gap:12px;padding:11px 0;border-bottom:1px solid var(--line-soft)}
.split-row:last-child{border-bottom:none}
.split-row .grow{flex:1}
.split-row .s-name{font-weight:600;font-size:14px}
.split-row .s-val{width:96px}
.split-row .s-val .input{padding:9px 10px;text-align:right;font-weight:700}
.split-row .s-fixed{font-weight:700;font-variant-numeric:tabular-nums;color:var(--ink-soft)}
.toggle-check{width:24px;height:24px;border-radius:7px;border:2px solid var(--line);
  display:flex;align-items:center;justify-content:center;cursor:pointer;flex:none;color:#fff}
.toggle-check.on{background:var(--upi);border-color:var(--upi)}

/* Sum tracker under a split */
.sum-track{display:flex;justify-content:space-between;align-items:center;
  padding:12px 14px;border-radius:var(--radius-sm);font-size:14px;font-weight:700;margin-top:6px}
.sum-track.ok{background:var(--upi-bg);color:var(--upi)}
.sum-track.bad{background:var(--owe-bg);color:var(--owe)}

/* --------------------------------------------------------------------------
   Balance summary hero
   -------------------------------------------------------------------------- */
.hero{
  background:linear-gradient(150deg,#0a7d4d,#075c39);color:#fff;
  border-radius:var(--radius);padding:20px;box-shadow:var(--shadow);
}
.hero.owe{background:linear-gradient(150deg,#b5411f,#8f3117)}
.hero.settled{background:linear-gradient(150deg,#55504a,#3a3630)}
.hero .h-label{font-size:13px;opacity:.85;font-weight:600}
.hero .h-amt{font-size:34px;font-weight:800;letter-spacing:-.02em;margin-top:2px;font-variant-numeric:tabular-nums}
.hero .h-sub{font-size:13px;opacity:.85;margin-top:6px}

/* Debt line (who owes whom) */
.debt{display:flex;align-items:center;gap:10px;padding:14px 16px;border-bottom:1px solid var(--line-soft)}
.debt:last-child{border-bottom:none}
.debt .flow{flex:1;font-size:14px}
.debt .flow b{font-weight:700}
.debt .arrow{color:var(--ink-faint)}

/* --------------------------------------------------------------------------
   Notices / callouts
   -------------------------------------------------------------------------- */
.notice{
  display:flex;gap:10px;align-items:flex-start;
  background:var(--upi-bg);border:1px solid #cfe8db;color:var(--upi-dark);
  border-radius:var(--radius-sm);padding:12px 14px;font-size:13.5px;line-height:1.5;
}
.notice .ic{flex:none;font-size:16px;margin-top:1px}
.notice.hold{background:var(--hold-bg);border-color:#e8d9a8;color:var(--hold)}
.notice.info{background:#e8effb;border-color:#c9dbf5;color:var(--blue)}
.notice.plain{background:var(--line-soft);border-color:var(--line);color:var(--ink-soft)}

/* prototype-only inline label */
.proto-tag{
  display:inline-block;font-size:10px;font-weight:800;letter-spacing:.05em;
  background:var(--hold-bg);color:var(--hold);padding:2px 7px;border-radius:5px;
  vertical-align:middle;text-transform:uppercase;
}

/* --------------------------------------------------------------------------
   Empty states
   -------------------------------------------------------------------------- */
.empty{text-align:center;padding:48px 20px;color:var(--ink-faint)}
.empty .big{font-size:44px;margin-bottom:10px}
.empty h3{color:var(--ink);font-size:17px;margin:0 0 6px}
.empty p{margin:0 0 18px;font-size:14px}

/* --------------------------------------------------------------------------
   Auth screen (no phone chrome)
   -------------------------------------------------------------------------- */
.auth-wrap{min-height:100vh;display:flex;flex-direction:column;justify-content:center;
  padding:32px 24px;max-width:var(--maxw);margin:0 auto}
.auth-logo{font-weight:800;font-size:30px;letter-spacing:-.02em;text-align:center;margin-bottom:6px}
.auth-logo .k{color:var(--upi)}
.auth-sub{text-align:center;color:var(--ink-soft);margin-bottom:30px;font-size:14px}
.auth-switch{text-align:center;margin-top:20px;font-size:14px;color:var(--ink-soft)}
.auth-switch a{color:var(--upi);font-weight:700}
.divider{display:flex;align-items:center;gap:12px;color:var(--ink-faint);font-size:12px;margin:20px 0}
.divider::before,.divider::after{content:"";flex:1;height:1px;background:var(--line)}

/* --------------------------------------------------------------------------
   Modal / sheet
   -------------------------------------------------------------------------- */
.sheet-backdrop{
  position:fixed;inset:0;background:rgba(28,26,23,.45);z-index:120;
  display:none;align-items:flex-end;justify-content:center;
}
.sheet-backdrop.open{display:flex}
.sheet{
  background:var(--panel);width:100%;max-width:var(--maxw);
  border-radius:20px 20px 0 0;padding:8px 20px 26px;
  animation:slideup .22s ease;
}
@keyframes slideup{from{transform:translateY(100%)}to{transform:translateY(0)}}
.sheet .grab{width:40px;height:4px;background:var(--line);border-radius:2px;margin:8px auto 16px}
.sheet h3{margin:0 0 6px;font-size:18px}

/* misc */
.stat-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.stat{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius-sm);padding:14px}
.stat .s-k{font-size:12px;color:var(--ink-faint);font-weight:600}
.stat .s-v{font-size:20px;font-weight:800;margin-top:3px;font-variant-numeric:tabular-nums}
.list-flush{margin:0 -16px}
.divider-line{height:1px;background:var(--line);margin:16px 0}
.spacer{height:8px}
.spacer-lg{height:20px}