:root {
  --bg: #ffffff; --fg: #0f2a3a; --muted: #5b7384; --line: #dbe5ec;
  --accent: #0b6fa4; --curve-fill: rgba(11, 111, 164, .14); --hi: #0b6fa4; --lo: #a35a00;
}
:root[data-theme="dark"] {
  --bg: #0d1f2b; --fg: #e8f1f6; --muted: #8fa6b5; --line: #24404f;
  --accent: #5cc0ee; --curve-fill: rgba(92, 192, 238, .16); --hi: #5cc0ee; --lo: #f0b25c;
}
@media (prefers-color-scheme: dark) {
  :root[data-theme="auto"] {
    --bg: #0d1f2b; --fg: #e8f1f6; --muted: #8fa6b5; --line: #24404f;
    --accent: #5cc0ee; --curve-fill: rgba(92, 192, 238, .16); --hi: #5cc0ee; --lo: #f0b25c;
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; background: var(--bg); color: var(--fg);
  font: 14px/1.4 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
#tm { padding: 14px 16px 10px; max-width: 720px; margin: 0 auto; }
h1 { font-size: 16px; margin: 0; font-weight: 650; }
.tm-sub { color: var(--muted); font-size: 12px; margin: 2px 0 10px; }
.tm-next { font-size: 15px; margin: 0 0 6px; }
.tm-next strong { color: var(--accent); }
svg.tm-chart { width: 100%; height: auto; display: block; }
.tm-axis { fill: var(--muted); font-size: 12px; }
.tm-lbl { fill: var(--fg); font-size: 12px; font-weight: 600; }
.tm-grid { stroke: var(--line); stroke-width: 1; }
.tm-curve { fill: none; stroke: var(--accent); stroke-width: 2; }
/* Observed water level (NWLON): the app's observed blue, over the prediction. */
.tm-observed { fill: none; stroke: #58a6ff; stroke-width: 2.4; stroke-linecap: round; stroke-linejoin: round; }
.tm-live { font-size: 13px; margin: 0 0 6px; color: var(--muted); }
.tm-live b { color: var(--fg); }
.tm-area { fill: var(--curve-fill); stroke: none; }
.tm-now { stroke: var(--fg); stroke-width: 1; stroke-dasharray: 3 3; }
.tm-hilo { display: grid; grid-template-columns: repeat(auto-fit, minmax(110px, 1fr)); gap: 6px; margin: 8px 0 14px; }
.tm-hilo > div { border: 1px solid var(--line); border-radius: 8px; padding: 6px 8px; }
.tm-hilo b { display: block; font-size: 12px; color: var(--muted); font-weight: 600; }
.tm-hilo .H b { color: var(--hi); } .tm-hilo .L b { color: var(--lo); }
h2 { font-size: 13px; margin: 6px 0 6px; color: var(--muted); text-transform: uppercase; letter-spacing: .05em; }
.tm-fc { display: grid; grid-auto-flow: column; grid-auto-columns: minmax(104px, 1fr); gap: 6px; overflow-x: auto; padding-bottom: 4px; }
.tm-fc > div { border: 1px solid var(--line); border-radius: 8px; padding: 8px; font-size: 12px; }
.tm-fc .n { font-weight: 650; font-size: 12px; }
.tm-fc .t { font-size: 22px; font-weight: 650; margin: 2px 0; }
.tm-fc .s { color: var(--muted); }
footer { display: flex; justify-content: space-between; gap: 8px; flex-wrap: wrap;
  border-top: 1px solid var(--line); margin-top: 10px; padding-top: 8px; font-size: 11px; color: var(--muted); }
footer a { color: var(--accent); text-decoration: none; font-weight: 600; }
.tm-status { color: var(--muted); }
.tm-err { color: #b3261e; }