/* India Air Quality: glass cards over slow waves of colour, light and dark, hand-written SVG charts. */
:root {
  color-scheme: light;
  --page: #eef1f6;
  --glass: rgba(252, 252, 251, 0.78);
  --glass-strong: rgba(252, 252, 251, 0.92);
  --glass-border: rgba(255, 255, 255, 0.7);
  --ring: rgba(11, 11, 11, 0.08);
  --shadow: 0 10px 40px rgba(31, 45, 80, 0.10);
  --ink: #0b0b0b;
  --ink-2: #52514e;
  --muted: #6f6d68;
  --grid: #e1e0d9;
  --axis: #c3c2b7;
  --surface: #fcfcfb;
  --s1: #2a78d6; --s2: #eb6834; --s3: #1baf7a; --s4: #eda100;
  --neutral-series: #9b9992;
  --good: #0ca30c; --warning: #fab219; --critical: #d03b3b;
  --o1: #86b6ef; --o2: #5598e7; --o3: #2a78d6; --o4: #1c5cab; --o5: #104281; --o6: #0b2a52;
  --seq-lo: #e3eefc; --seq-hi: #0b2a52;
  --blob-a: #8fb8f5; --blob-b: #f5b38f; --blob-c: #8fe0c2;
  --wave-alpha: 0.75;
  --chip: rgba(11, 11, 11, 0.05);
  --chip-on: #0b0b0b; --chip-on-ink: #fcfcfb;
}
@media (prefers-color-scheme: dark) {
  :root:where(:not([data-theme="light"])) {
    color-scheme: dark;
    --page: #0d0f14;
    --glass: rgba(26, 26, 25, 0.72);
    --glass-strong: rgba(26, 26, 25, 0.9);
    --glass-border: rgba(255, 255, 255, 0.08);
    --ring: rgba(255, 255, 255, 0.08);
    --shadow: 0 10px 40px rgba(0, 0, 0, 0.45);
    --ink: #f0efec; --ink-2: #c3c2b7; --muted: #9a988f;
    --grid: #2c2c2a; --axis: #383835; --surface: #1a1a19;
    --s1: #3987e5; --s2: #d95926; --s3: #199e70; --s4: #c98500;
    --neutral-series: #75736c;
    --o1: #cde2fb; --o2: #9ec5f4; --o3: #6da7ec; --o4: #3987e5; --o5: #256abf; --o6: #184f95;
    --seq-lo: #1b2a40; --seq-hi: #9ec5f4;
    --blob-a: #1d4f9c; --blob-b: #8a3a17; --blob-c: #0f6b4b;
    --wave-alpha: 0.65;
    --chip: rgba(255, 255, 255, 0.07);
    --chip-on: #f0efec; --chip-on-ink: #1a1a19;
  }
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --page: #0d0f14;
  --glass: rgba(26, 26, 25, 0.72);
  --glass-strong: rgba(26, 26, 25, 0.9);
  --glass-border: rgba(255, 255, 255, 0.08);
  --ring: rgba(255, 255, 255, 0.08);
  --shadow: 0 10px 40px rgba(0, 0, 0, 0.45);
  --ink: #f0efec; --ink-2: #c3c2b7; --muted: #9a988f;
  --grid: #2c2c2a; --axis: #383835; --surface: #1a1a19;
  --s1: #3987e5; --s2: #d95926; --s3: #199e70; --s4: #c98500;
  --neutral-series: #75736c;
  --o1: #cde2fb; --o2: #9ec5f4; --o3: #6da7ec; --o4: #3987e5; --o5: #256abf; --o6: #184f95;
  --seq-lo: #1b2a40; --seq-hi: #9ec5f4;
  --blob-a: #1d4f9c; --blob-b: #8a3a17; --blob-c: #0f6b4b;
  --wave-alpha: 0.65;
  --chip: rgba(255, 255, 255, 0.07);
  --chip-on: #f0efec; --chip-on-ink: #1a1a19;
}

* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--page);
  color: var(--ink);
  font: 15px/1.55 system-ui, -apple-system, "Segoe UI", sans-serif;
  min-height: 100vh;
  overflow-x: hidden;
}

/* background: slow waves of soft colour, drawn small by bg.js and scaled up */
.sky { position: fixed; inset: 0; z-index: 0; pointer-events: none; background: var(--page); }
.sky canvas { position: absolute; inset: 0; width: 100%; height: 100%; }

main { position: relative; z-index: 1; max-width: 1180px; margin: 0 auto; padding: 28px 16px 64px; }

.glass {
  background: var(--glass);
  -webkit-backdrop-filter: blur(18px) saturate(140%);
  backdrop-filter: blur(18px) saturate(140%);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow), inset 0 0 0 1px var(--ring);
  border-radius: 20px;
}

/* header */
header.top { position: relative; display: flex; flex-wrap: wrap; gap: 16px; align-items: flex-end; justify-content: space-between; padding: 20px 24px; }
header.top > div:first-child { padding-right: 72px; }
header.top h1 { font-size: 26px; line-height: 1.2; margin: 0 0 4px; letter-spacing: -0.01em; }
header.top p { margin: 0; color: var(--ink-2); max-width: 640px; }
.top-right { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
/* light/dark switch in the header's top-right corner; the knob follows the theme in CSS, so it is right before JS runs */
.theme-switch { position: absolute; top: 18px; right: 20px; width: 56px; height: 30px; padding: 0; border-radius: 999px;
  border: 1px solid var(--ring); background: var(--chip); cursor: pointer; }
.theme-switch:hover { background: var(--glass-strong); }
.theme-switch:focus-visible { outline: 2px solid var(--s1); outline-offset: 2px; }
.theme-switch .knob { position: absolute; top: 3px; left: 3px; width: 22px; height: 22px; border-radius: 50%;
  display: grid; place-items: center; background: #fcfcfb; box-shadow: 0 1px 4px rgba(0, 0, 0, 0.25);
  transition: transform 0.2s ease; }
.theme-switch svg { grid-area: 1 / 1; width: 14px; height: 14px; fill: none; stroke-width: 2; stroke-linecap: round; }
.theme-switch .sun { stroke: var(--s4); fill: none; }
.theme-switch .sun circle { fill: var(--s4); }
.theme-switch .moon { fill: var(--s1); stroke: none; display: none; }
:root[data-theme="dark"] .theme-switch .knob { transform: translateX(26px); }
:root[data-theme="dark"] .theme-switch .sun { display: none; }
:root[data-theme="dark"] .theme-switch .moon { display: block; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-switch .knob { transform: translateX(26px); }
  :root:not([data-theme="light"]) .theme-switch .sun { display: none; }
  :root:not([data-theme="light"]) .theme-switch .moon { display: block; }
}
.pill { display: inline-flex; align-items: center; gap: 8px; padding: 7px 12px; border-radius: 999px; background: var(--chip); color: var(--ink-2); font-size: 13px; }
.pill b { color: var(--ink); font-weight: 600; }
.status-icon { width: 16px; height: 16px; flex: none; }
.btn { font: inherit; font-size: 13px; color: var(--ink); background: var(--chip); border: 1px solid var(--ring); border-radius: 999px; padding: 6px 12px; cursor: pointer; }
.btn:hover { background: var(--glass-strong); }
.btn:focus-visible, select:focus-visible, .chip:focus-visible { outline: 2px solid var(--s1); outline-offset: 2px; }

/* KPI tiles */
.kpis { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; margin: 16px 0; }
.kpi { padding: 18px 20px; }
.kpi .label { color: var(--ink-2); font-size: 13px; }
.kpi .value { font-size: 32px; font-weight: 650; letter-spacing: -0.02em; line-height: 1.2; margin-top: 4px; }
.kpi .sub { color: var(--muted); font-size: 12.5px; margin-top: 2px; }

.note { padding: 16px 20px; margin-bottom: 16px; color: var(--ink-2); }
.note b { color: var(--ink); }

/* cards */
.grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.card { padding: 20px 20px 16px; min-width: 0; }
.card.wide { grid-column: 1 / -1; }
.card-head { display: flex; flex-wrap: wrap; gap: 10px 16px; align-items: flex-start; justify-content: space-between; }
.card h2 { font-size: 17px; margin: 0; letter-spacing: -0.005em; }
.card .sub { color: var(--ink-2); font-size: 13px; margin: 2px 0 0; }
.controls { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.seg { display: inline-flex; background: var(--chip); border-radius: 999px; padding: 3px; }
.chip { font: inherit; font-size: 12.5px; border: 0; background: transparent; color: var(--ink-2); padding: 5px 11px; border-radius: 999px; cursor: pointer; }
.chip[aria-pressed="true"] { background: var(--chip-on); color: var(--chip-on-ink); }
select { font: inherit; font-size: 13px; color: var(--ink); background: var(--chip); border: 1px solid var(--ring); border-radius: 999px; padding: 5px 10px; }
select option { background: var(--surface); color: var(--ink); }

/* tabs */
.tabs { display: flex; width: fit-content; margin: 16px 0 0; }
.tabs .chip { font-size: 13.5px; padding: 7px 18px; }
.tabs .chip[aria-selected="true"] { background: var(--chip-on); color: var(--chip-on-ink); }
[role="tabpanel"] > .grid:first-child { margin-top: 16px; }

/* City tab */
.today { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.25fr); gap: 28px; margin-top: 14px; }
.today .sub { margin-bottom: 6px; }
.big { display: flex; flex-wrap: wrap; align-items: baseline; gap: 8px 12px; }
.big b { font-size: 52px; font-weight: 650; letter-spacing: -0.02em; line-height: 1; font-variant-numeric: tabular-nums; }
.big-label { color: var(--ink-2); font-size: 14px; }
.badge { display: inline-flex; align-items: center; gap: 6px; padding: 4px 10px; border-radius: 999px; background: var(--chip); font-size: 13px; font-weight: 600; }
.badge i { width: 10px; height: 10px; border-radius: 3px; }
.today dl { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px 18px; margin: 20px 0 0; }
.today dt { color: var(--ink-2); font-size: 12.5px; }
.today dd { margin: 0; font-weight: 600; font-variant-numeric: tabular-nums; }
.chart .pick { cursor: pointer; }
/* the City and Pipeline tables are short: show them whole, and keep dates and names on one line */
#panel-city .table-wrap, #panel-check .table-wrap, #panel-pipeline .table-wrap { max-height: none; }
#panel-city td:first-child, #panel-check td:first-child, #panel-pipeline td:first-child { white-space: nowrap; }
.check-note { margin: 16px 0 0; }

/* Pipeline tab */
.flow { list-style: none; padding: 0; margin: 14px 0 4px; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; }
.flow li { position: relative; padding: 12px 14px; border-radius: 14px; background: var(--chip); }
.flow li b { display: block; margin-bottom: 2px; }
.flow li span { display: block; color: var(--ink-2); font-size: 13px; }
.flow li .metric { margin-top: 8px; font-size: 13px; font-weight: 600; font-variant-numeric: tabular-nums; }
.flow li:not(:last-child)::after { content: "→"; position: absolute; right: -13px; top: 50%; transform: translateY(-50%); color: var(--muted); }
.chart a { cursor: pointer; }
h3.minor { font-size: 14px; margin: 18px 0 0; }
code { font-size: 12px; overflow-wrap: anywhere; }

.finding { margin: 12px 0 6px; padding: 10px 12px; border-radius: 12px; background: var(--chip); color: var(--ink-2); font-size: 13.5px; }
.finding b { color: var(--ink); }

.legend { display: flex; flex-wrap: wrap; gap: 6px 14px; margin: 10px 0 4px; font-size: 12.5px; color: var(--ink-2); }
.legend span { display: inline-flex; align-items: center; gap: 6px; }
.legend i { width: 12px; height: 12px; border-radius: 3px; display: inline-block; }
.legend i.line { height: 3px; border-radius: 2px; width: 16px; }

.chart { position: relative; width: 100%; }
.chart svg { display: block; width: 100%; height: auto; overflow: visible; }
.chart text { fill: var(--muted); font-size: 11px; font-variant-numeric: tabular-nums; }
.chart text.lbl { fill: var(--ink-2); font-size: 11.5px; }
.chart text.val { fill: var(--ink); font-size: 11.5px; font-weight: 600; }
.chart text.ref { paint-order: stroke; stroke: var(--surface); stroke-width: 4px; stroke-linejoin: round; }
.chart .gridline { stroke: var(--grid); stroke-width: 1; }
.chart .baseline { stroke: var(--axis); stroke-width: 1; }
.chart .refline { stroke: var(--axis); stroke-width: 1; stroke-dasharray: 3 4; }
.chart .marker-line { stroke: var(--ink-2); stroke-width: 1; stroke-dasharray: 2 3; }
.chart .series { fill: none; stroke-width: 2; stroke-linejoin: round; stroke-linecap: round; }
.chart .hit { fill: transparent; }
.chart .crosshair { stroke: var(--ink-2); stroke-width: 1; opacity: 0; }
.chart .dot { stroke: var(--surface); stroke-width: 2; opacity: 0; }

/* entrance animations: bars grow from the baseline, lines draw, cells fade */
.grow-x { transform-box: fill-box; transform-origin: left center; transform: scaleX(0); transition: transform 900ms cubic-bezier(.2,.8,.2,1); }
.grow-y { transform-box: fill-box; transform-origin: center bottom; transform: scaleY(0); transition: transform 900ms cubic-bezier(.2,.8,.2,1); }
.draw { transition: stroke-dashoffset 1400ms cubic-bezier(.4,.1,.2,1); }
.fade { opacity: 0; transition: opacity 600ms ease; }
.in .grow-x { transform: scaleX(1); }
.in .grow-y { transform: scaleY(1); }
.in .fade { opacity: 1; }
.reveal { opacity: 0; transform: translateY(14px); transition: opacity 700ms ease, transform 700ms ease; }
.reveal.shown { opacity: 1; transform: none; }

.tooltip {
  position: fixed; z-index: 10; pointer-events: none; min-width: 140px; max-width: 260px;
  padding: 10px 12px; border-radius: 12px; font-size: 12.5px; color: var(--ink);
  background: var(--glass-strong); -webkit-backdrop-filter: blur(14px); backdrop-filter: blur(14px);
  border: 1px solid var(--glass-border); box-shadow: var(--shadow), inset 0 0 0 1px var(--ring);
  opacity: 0; transition: opacity 120ms ease;
}
.tooltip.on { opacity: 1; }
.tooltip .t-title { font-weight: 600; margin-bottom: 4px; }
.tooltip .t-row { display: flex; justify-content: space-between; gap: 12px; color: var(--ink-2); }
.tooltip .t-row b { color: var(--ink); font-weight: 600; font-variant-numeric: tabular-nums; }
.tooltip .sw { display: inline-block; width: 8px; height: 8px; border-radius: 2px; margin-right: 6px; }

.table-wrap { max-height: 320px; overflow: auto; margin-top: 8px; border-radius: 12px; border: 1px solid var(--ring); }
table { border-collapse: collapse; width: 100%; font-size: 12.5px; }
th, td { padding: 6px 10px; text-align: right; border-bottom: 1px solid var(--grid); font-variant-numeric: tabular-nums; }
th:first-child, td:first-child { text-align: left; }
th { position: sticky; top: 0; background: var(--glass-strong); color: var(--ink-2); font-weight: 600; }
.table-toggle { margin-top: 8px; }

footer { margin-top: 16px; padding: 18px 22px; color: var(--ink-2); font-size: 13px; }
footer a, .note a { color: var(--s1); }
footer ul { margin: 6px 0 0; padding-left: 18px; }

/* guided tour: the spotlight dims everything around the target; the page stays clickable */
.tour-spot, .tour-pop { position: fixed; z-index: 20; display: none; }
.tour-spot.on, .tour-pop.on { display: block; }
.tour-spot {
  pointer-events: none; border-radius: 24px;
  box-shadow: 0 0 0 9999px rgba(8, 10, 16, 0.55), 0 0 0 2px var(--s1);
  transition: left 350ms ease, top 350ms ease, width 350ms ease, height 350ms ease;
}
.tour-pop {
  padding: 16px 18px 14px; border-radius: 18px; color: var(--ink);
  background: var(--glass-strong); -webkit-backdrop-filter: blur(18px); backdrop-filter: blur(18px);
  border: 1px solid var(--glass-border); box-shadow: var(--shadow), inset 0 0 0 1px var(--ring);
  transition: left 350ms ease, top 350ms ease;
}
/* keep the spotlight's padding on screen when a target scrolls to the top */
.touring #freshness, .touring main > section, .touring .card, .touring footer { scroll-margin: 24px; }
.tour-pop h3 { margin: 2px 0 6px; font-size: 16px; }
.tour-pop p { margin: 0 0 12px; color: var(--ink-2); font-size: 13.5px; }
.tour-count { color: var(--muted); font-size: 12px; font-variant-numeric: tabular-nums; }
.tour-actions { display: flex; gap: 8px; align-items: center; }
.tour-gap { flex: 1; }
.tour-next { background: var(--chip-on); color: var(--chip-on-ink); border-color: transparent; }
.tour-next:hover { background: var(--chip-on); opacity: 0.9; }
.btn:disabled { opacity: 0.4; cursor: default; }

@media (max-width: 860px) {
  .kpis { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid { grid-template-columns: 1fr; }
  .kpi .value { font-size: 26px; }
  .today { grid-template-columns: 1fr; }
  .flow { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .flow li:nth-child(2)::after { content: none; }
}
@media (max-width: 520px) {
  .flow { grid-template-columns: 1fr; }
  .flow li::after { content: none !important; }
}
@media (prefers-reduced-motion: reduce) {
  .grow-x, .grow-y, .draw, .fade, .reveal, .tour-spot, .tour-pop, .theme-switch .knob { transition: none; }
}
.no-motion *, .no-motion *::before { transition: none !important; animation: none !important; }
.no-motion .grow-x, .no-motion .grow-y { transform: none; }
.no-motion .fade, .no-motion .reveal { opacity: 1; transform: none; }
@media (forced-colors: active) {
  .glass { backdrop-filter: none; }
}

/* "Ask the data" chat (chat.js): a button in the bottom-right corner that opens a panel above it */
.chat-fab { position: fixed; right: 20px; bottom: 20px; z-index: 15; display: inline-flex; align-items: center; gap: 8px;
  font: inherit; font-size: 14px; font-weight: 600; color: var(--ink); padding: 11px 16px; border-radius: 999px; cursor: pointer; }
.chat-fab svg { width: 18px; height: 18px; fill: none; stroke: var(--s1); stroke-width: 2; stroke-linejoin: round; }
.chat-fab:hover { background: var(--glass-strong); }
.chat-fab:focus-visible, .chat-close:focus-visible, .chat-form input:focus-visible { outline: 2px solid var(--s1); outline-offset: 2px; }
.chat-panel { position: fixed; right: 20px; bottom: 76px; z-index: 15; width: 390px; height: min(560px, calc(100vh - 110px));
  display: flex; flex-direction: column; background: var(--glass-strong); overflow: hidden; }
.chat-panel[hidden] { display: none; }
.chat-head { display: flex; gap: 12px; align-items: flex-start; padding: 14px 16px 10px; border-bottom: 1px solid var(--ring); }
.chat-head p { margin: 2px 0 0; font-size: 12.5px; color: var(--muted); line-height: 1.4; }
.chat-clear { margin-left: auto; flex: none; }
.chat-clear:not([hidden]) + .chat-close { margin-left: 0; }
.chat-close { margin-left: auto; flex: none; width: 30px; height: 30px; border-radius: 50%; border: 1px solid var(--ring);
  background: var(--chip); color: var(--ink); font-size: 18px; line-height: 1; cursor: pointer; }
.chat-log { flex: 1; overflow-y: auto; padding: 14px 16px; display: flex; flex-direction: column; gap: 10px; }
.chat-chips { display: flex; flex-direction: column; align-items: flex-start; gap: 6px; }
.chat-chips::before { content: "Try asking"; font-size: 12.5px; color: var(--muted); }
.chat-chips .chip { background: var(--chip); color: var(--ink); text-align: left; }
.chat-chips .chip:hover { background: var(--glass); box-shadow: inset 0 0 0 1px var(--ring); }
.chat-msg { max-width: 88%; padding: 9px 12px; border-radius: 14px; font-size: 14px; line-height: 1.5; overflow-wrap: anywhere; }
.chat-msg p { margin: 0; }
.chat-msg p + p, .chat-msg ul { margin-top: 6px; }
.chat-msg ul { margin-bottom: 0; padding-left: 18px; }
.chat-msg.user { align-self: flex-end; background: var(--chip-on); color: var(--chip-on-ink); border-bottom-right-radius: 4px; }
.chat-msg.bot { align-self: flex-start; background: var(--chip); border-bottom-left-radius: 4px; }
.chat-msg.thinking { color: var(--muted); }
.chat-msg.error { box-shadow: inset 3px 0 0 var(--warning); }
.chat-src { margin-top: 6px; font-size: 12px; color: var(--muted); }
.chat-form { display: flex; gap: 8px; padding: 10px 12px 12px; border-top: 1px solid var(--ring); }
.chat-form input { flex: 1; min-width: 0; font: inherit; font-size: 14px; color: var(--ink); background: var(--surface);
  border: 1px solid var(--ring); border-radius: 999px; padding: 8px 14px; }
.chat-send { font-size: 14px; padding: 8px 16px; background: var(--chip-on); color: var(--chip-on-ink); border-color: transparent; }
.chat-send:hover { background: var(--chip-on); opacity: 0.9; }
@media (max-width: 520px) {
  .chat-fab { right: 16px; bottom: 16px; }
  .chat-panel { left: 16px; right: 16px; bottom: 72px; width: auto; height: calc(100vh - 100px); }
}