/* £1M by 50 - mobile-first, system fonts, no frameworks */
:root{
  --ink:#1a2332; --muted:#5b6b82; --line:#e2e8f0; --bg:#f7f9fc; --card:#ffffff;
  --a:#2563eb; --b:#64748b;
  --radius:14px;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.55;font-size:16px}
.wrap{max-width:1080px;margin:0 auto;padding:0 16px}

/* Header */
.top{background:linear-gradient(160deg,#0f2440,#1e3a5f);color:#fff;padding:36px 0 30px}
.kicker{margin:0 0 6px;font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:#9db4d4}
.top h1{margin:0 0 8px;font-size:clamp(30px,6vw,46px);line-height:1.1;letter-spacing:-.01em}
.sub{margin:0 0 18px;color:#c9d6ea;max-width:640px}
.maths{background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.16);border-radius:var(--radius);
  padding:14px 16px;font-size:14.5px;color:#e8eef7}
.maths strong{color:#ffd166}
.maths .row{display:flex;gap:8px;flex-wrap:wrap;margin-top:8px}
.maths .pill{background:rgba(255,255,255,.1);border-radius:999px;padding:4px 12px;font-size:13px;white-space:nowrap}

/* Tabs */
.tabs{display:flex;gap:8px;margin:18px auto 4px;position:sticky;top:0;z-index:20;background:var(--bg);padding:10px 16px}
.tab{flex:1;display:flex;align-items:center;justify-content:center;gap:8px;border:2px solid var(--line);
  background:var(--card);border-radius:12px;padding:10px 6px;font-size:14px;font-weight:600;color:var(--ink);cursor:pointer}
.tab-letter{display:inline-flex;align-items:center;justify-content:center;width:26px;height:26px;border-radius:50%;
  background:#eef2f7;color:var(--ink);font-size:14px}
.tab[data-plan="a"].active{border-color:var(--a)} .tab[data-plan="a"].active .tab-letter{background:var(--a);color:#fff}
.tab[data-plan="b"].active{border-color:var(--b)} .tab[data-plan="b"].active .tab-letter{background:var(--b);color:#fff}
/* Backup tab reads secondary until selected */
.tab.backup-tab{opacity:.8}
.tab.backup-tab.active{opacity:1}
.tab-flag{font-size:10.5px;font-weight:700;text-transform:uppercase;letter-spacing:.06em;border-radius:999px;padding:3px 9px;white-space:nowrap}
.tab-flag.hero{background:var(--a);color:#fff}
.tab-flag.backup{background:#eef2f7;color:#64748b;border:1px solid var(--line)}
@media(max-width:520px){.tab-name{display:none}.tab-flag{display:none}.tab{padding:10px}}

/* Plan head */
.plan-head{margin:14px 0 6px}
.plan-head h2{margin:0;font-size:24px}
.plan-head .tagline{margin:4px 0 12px;color:var(--muted)}
.stat-row{display:flex;gap:10px;flex-wrap:wrap}
.stat{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:10px 14px;flex:1;min-width:140px}
.stat .k{font-size:12px;color:var(--muted);text-transform:uppercase;letter-spacing:.06em}
.stat .v{font-size:20px;font-weight:700}
.stat .v.a{color:var(--a)} .stat .v.b{color:var(--b)}
.plan-flag{display:inline-block;vertical-align:middle;font-size:11.5px;font-weight:700;text-transform:uppercase;
  letter-spacing:.07em;border-radius:999px;padding:4px 11px;margin-left:6px;white-space:nowrap}
.plan-flag.hero{background:var(--a);color:#fff}
.plan-flag.backup{background:#eef2f7;color:#64748b;border:1px solid var(--line)}

h2{font-size:20px;margin:28px 0 4px}
.hint{margin:0 0 12px;color:var(--muted);font-size:14px}

/* Rail */
.rail{display:flex;height:34px;border-radius:8px;overflow:hidden;margin-bottom:12px;border:1px solid var(--line)}
.rail-seg{display:flex;align-items:center;justify-content:center;color:#fff;font-size:11px;font-weight:600;
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis;padding:0 6px}

/* Timeline */
.timeline{display:flex;gap:12px;overflow-x:auto;padding-bottom:10px;scroll-snap-type:x mandatory;-webkit-overflow-scrolling:touch}
.phase{flex:0 0 290px;scroll-snap-align:start;background:var(--card);border:1px solid var(--line);
  border-radius:var(--radius);padding:14px;display:flex;flex-direction:column;gap:10px}
.phase-top{border-top:4px solid;border-radius:2px;padding-top:8px}
.phase h3{margin:0 0 2px;font-size:17px}
.phase .dates{font-size:13px;color:var(--muted)}
.phase .econ{font-size:13.5px;background:#f1f5f9;border-radius:8px;padding:8px 10px}
.phase .econ b{display:block;font-size:12px;color:var(--muted);text-transform:uppercase;letter-spacing:.05em;font-weight:600}
.mile{text-align:left;background:#fff;border:1px solid var(--line);border-radius:10px;padding:9px 10px 9px 12px;
  cursor:pointer;position:relative;font-size:14px;width:100%;color:var(--ink)}
.mile:hover{border-color:#94a3b8;background:#f8fafc}
.mile::before{content:"";position:absolute;left:0;top:0;bottom:0;width:4px;border-radius:10px 0 0 10px;background:var(--pc,#2563eb)}
.mile .md{font-size:12px;color:var(--muted)}
.mile .mt{font-weight:600}
@media(min-width:1100px){
  .timeline{display:grid;grid-template-columns:repeat(4,1fr);overflow:visible}
  .phase{flex:none}
}

/* Chart */
.chart-bar{margin:6px 0 10px}
.btn{border:1px solid var(--line);background:var(--card);border-radius:999px;padding:8px 16px;
  font-size:14px;font-weight:600;cursor:pointer;color:var(--ink)}
.btn.on{background:var(--ink);color:#fff;border-color:var(--ink)}
.chart-wrap{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:10px}
#chart{width:100%;height:300px;display:block}
.legend{display:flex;gap:14px;flex-wrap:wrap;margin:10px 2px;font-size:13.5px;color:var(--muted)}
.legend .sw{display:inline-block;width:22px;height:4px;border-radius:2px;vertical-align:middle;margin-right:6px}

/* Verdict */
.verdict{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:16px;margin-top:22px}
.verdict h2{margin-top:0}
.verdict .big{font-size:26px;font-weight:800;margin:6px 0}
.verdict p{margin:8px 0}

/* Assumptions */
.assume-grid{display:grid;gap:12px;margin-bottom:8px}
@media(min-width:760px){.assume-grid{grid-template-columns:1fr 1fr}}
.assume{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:14px 16px}
.assume h3{margin:0 0 8px;font-size:16px}
.assume ul{margin:0;padding-left:20px;font-size:14.5px}
.assume li{margin-bottom:6px}
.assume.break{border-left:4px solid #dc2626}
.assume.boost{border-left:4px solid #15803d}
.assume.base{border-left:4px solid #64748b}

/* Modal */
.modal-backdrop{position:fixed;inset:0;background:rgba(15,23,42,.55);z-index:50;display:flex;
  align-items:flex-end;justify-content:center;padding:0}
.modal{background:#fff;width:100%;max-width:560px;max-height:88vh;overflow:auto;border-radius:18px 18px 0 0;
  padding:20px 20px 28px;position:relative}
@media(min-width:700px){.modal-backdrop{align-items:center;padding:20px}.modal{border-radius:18px}}
.modal-close{position:absolute;top:10px;right:14px;border:none;background:none;font-size:28px;cursor:pointer;color:var(--muted)}
.modal-date{font-size:13px;color:var(--muted);margin:0 0 4px;text-transform:uppercase;letter-spacing:.06em}
.modal h3{margin:0 0 12px;font-size:20px;padding-right:30px}
.modal-dl{margin:0}
.modal-dl>div{margin-bottom:12px}
.modal-dl dt{font-size:12px;text-transform:uppercase;letter-spacing:.07em;color:var(--muted);font-weight:700;margin-bottom:2px}
.modal-dl dd{margin:0;font-size:15px}
[hidden]{display:none!important}

footer{padding:26px 16px 40px}
.disclaimer{font-size:13.5px;color:var(--muted);background:#fff8e6;border:1px solid #f0dfae;border-radius:12px;padding:14px 16px}
.foot-note{font-size:12.5px;color:#8a97ab;margin-top:10px}

/* View tabs */
.view-tabs{display:flex;gap:8px;margin:16px 0 4px}
.view-tab{flex:1;border:2px solid var(--line);background:var(--card);border-radius:12px;padding:9px 6px;
  font-size:14px;font-weight:600;color:var(--muted);cursor:pointer}
.view-tab.active{border-color:var(--ink);color:var(--ink)}

/* Month by month */
.mhead{display:grid;grid-template-columns:78px 104px 1fr 86px 86px;gap:8px;padding:8px 10px;
  font-size:11.5px;text-transform:uppercase;letter-spacing:.06em;color:var(--muted);font-weight:700}
.mhead .num{text-align:right}
.yr{margin-bottom:10px;border:1px solid var(--line);border-radius:var(--radius);background:var(--card)}
.yr-head{position:sticky;top:64px;z-index:5;width:100%;display:flex;align-items:center;gap:10px;
  background:#fff;border:none;border-bottom:1px solid var(--line);border-radius:var(--radius) var(--radius) 0 0;
  padding:10px 12px;cursor:pointer;font-size:15px;font-weight:700;color:var(--ink);text-align:left}
.yr-head[aria-expanded="false"]{border-radius:var(--radius);border-bottom:none}
.yr-name{font-size:16px}
.yr-meta{font-size:12.5px;font-weight:500;color:var(--muted)}
.yr-chev{margin-left:auto;color:var(--muted);transition:transform .15s}
.yr-head[aria-expanded="false"] .yr-chev{transform:rotate(-90deg)}
.yr-rows{border-radius:0 0 var(--radius) var(--radius);overflow:hidden}
.mrow{display:grid;grid-template-columns:78px 104px 1fr 86px 86px;gap:8px;align-items:start;
  padding:9px 10px 11px;border-top:1px solid #eef2f7;position:relative;font-size:13.5px}
.mc-month{font-weight:600;white-space:nowrap}
.mflag{color:#d97706;margin-left:4px;font-size:11px}
.ptag{display:inline-block;font-size:11px;font-weight:700;color:var(--muted);background:#eef2f7;
  border-radius:999px;padding:2px 8px;white-space:nowrap}
.mc-inv,.mc-nw{text-align:right;font-variant-numeric:tabular-nums;white-space:nowrap}
.mc-nw{font-weight:700}
.ev{display:block;font-size:11.5px;color:#b45309;font-weight:600}
.mc-bar{position:absolute;left:0;bottom:0;height:3px;opacity:.55;border-radius:0 3px 3px 0}
@media(max-width:640px){
  .mhead,.mrow{grid-template-columns:70px 1fr 72px 80px}
  .mh-phase,.mc-phase{display:none}
  .mrow{font-size:13px;padding:8px 8px 10px}
  .yr-head{top:58px}
}