/* silt — a geological survey sheet. Day: printed paper. Night: the same
   sheet in reverse, light linework on a dark ground. */

:root {
  --paper: #e4dcc7;
  --sheet: #f4eedf;
  --ink: #2a2016;
  --ink-2: #594836;
  --rule: #9b8567;
  --hair: #cbbb9d;
  --accent: #9b3117;
  --river: #2b479f;
  --sea: #9aa3c2;
  --shoal: #c0c2ce;
  --silt: #cdd0a0;
  --waterline: #2b479f;
  --coast: #1b2c6e;
  --contour: #6b4222;
  --stipple: #5e3f25;
  --btn-ink: #f4eedf;
  --shadow: 0 1px 0 #fffaf0 inset, 0 18px 40px -26px rgb(60 40 20 / 0.55);
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #0e0d0a;
    --sheet: #1a1813;
    --ink: #efe6d2;
    --ink-2: #c7baa0;
    --rule: #6a5f4d;
    --hair: #3b352b;
    --accent: #ec946c;
    --river: #7b95ea;
    --sea: #212b4b;
    --shoal: #353c55;
    --silt: #5f6444;
    --waterline: #6f88d8;
    --coast: #9fb0ea;
    --contour: #efe2c4;
    --stipple: #e8d3a8;
    --btn-ink: #1a1813;
    --shadow: 0 0 0 1px #2a261e, 0 24px 60px -30px rgb(0 0 0 / 0.9);
    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --paper: #0e0d0a;
  --sheet: #1a1813;
  --ink: #efe6d2;
  --ink-2: #c7baa0;
  --rule: #6a5f4d;
  --hair: #3b352b;
  --accent: #ec946c;
  --river: #7b95ea;
  --sea: #212b4b;
  --shoal: #353c55;
  --silt: #5f6444;
  --waterline: #6f88d8;
  --coast: #9fb0ea;
  --contour: #efe2c4;
  --stipple: #e8d3a8;
  --btn-ink: #1a1813;
  --shadow: 0 0 0 1px #2a261e, 0 24px 60px -30px rgb(0 0 0 / 0.9);
  color-scheme: dark;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  background-color: var(--paper);
  /* fibres in the paper */
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='220' height='220'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 .45 0 0 0 0 .38 0 0 0 0 .28 0 0 0 .07 0'/%3E%3C/filter%3E%3Crect width='220' height='220' filter='url(%23n)'/%3E%3C/svg%3E");
  color: var(--ink);
  font-family: "EB Garamond", "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  font-size: 17px;
  line-height: 1.4;
  font-feature-settings: "kern", "liga", "onum";
  overflow-x: hidden;
}

.sheet {
  max-width: 1320px;
  margin: 14px auto;
  padding: 14px 22px 12px;
  background: var(--sheet);
  box-shadow: var(--shadow);
}

.sheet-head,
.sheet-foot {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  font-variant-caps: all-small-caps;
  letter-spacing: 0.14em;
  font-size: 0.95rem;
  color: var(--ink-2);
}

.sheet-head {
  padding-bottom: 6px;
  border-bottom: 1px solid var(--ink);
  box-shadow: 0 2px 0 var(--sheet), 0 3px 0 var(--ink);
  margin-bottom: 16px;
}

.sheet-no {
  color: var(--ink);
  font-weight: 600;
}

.sheet-foot {
  margin-top: 14px;
  padding-top: 6px;
  border-top: 1px solid var(--rule);
  flex-wrap: wrap;
}

/* --- layout: tools | map | reference ------------------------------------ */

.sheet-body {
  display: grid;
  grid-template-columns: 220px minmax(0, auto) 240px;
  grid-template-rows: auto 1fr;
  grid-template-areas:
    "mast map ref"
    "tools map ref";
  justify-content: space-between;
  column-gap: 26px;
  align-items: start;
}

.masthead {
  grid-area: mast;
}

.margin-tools {
  grid-area: tools;
}

.map-wrap {
  grid-area: map;
}

.margin-ref {
  grid-area: ref;
}

.margin {
  min-width: 0;
}

.map-wrap {
  margin: 0;
  min-width: 0;
}

.map-frame {
  --size: min(calc(100vh - 150px), 820px);
  position: relative;
  width: var(--size);
  max-width: 100%;
  padding: 16px 0 0 22px; /* room for the kilometre ticks */
}

.neat {
  position: relative;
  aspect-ratio: 1;
  border: 1px solid var(--ink);
  padding: 4px;
}

.neat::after {
  /* inner neat line */
  content: "";
  position: absolute;
  inset: 3px;
  border: 1.5px solid var(--ink);
  pointer-events: none;
}

#map {
  display: block;
  width: 100%;
  height: 100%;
  touch-action: none;
  cursor: none;
  background: var(--sheet);
}

#map:focus {
  outline: none;
}

#map:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 5px;
}

.brush-ring {
  position: absolute;
  left: 0;
  top: 0;
  width: 0;
  height: 0;
  border: 1.5px solid var(--accent);
  border-radius: 50%;
  pointer-events: none;
  opacity: 0;
  transform: translate(-50%, -50%);
  box-shadow: 0 0 0 1px rgb(255 255 255 / 0.35);
}

.brush-ring::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 3px;
  height: 3px;
  margin: -1.5px 0 0 -1.5px;
  background: var(--accent);
  border-radius: 50%;
}

.brush-ring.is-on {
  opacity: 1;
}

.brush-ring.is-lower {
  border-style: dashed;
}

/* Notes sit low on the sheet, over the open sea, not over the land. */
.map-status {
  position: absolute;
  left: 50%;
  bottom: 7%;
  transform: translateX(-50%);
  margin: 0;
  max-width: 80%;
  padding: 0.5em 0.9em;
  background: var(--sheet);
  border: 1px solid var(--ink);
  text-align: center;
  font-style: italic;
}

.map-status:empty {
  display: none;
}

.ticks {
  position: absolute;
  inset: 0;
  pointer-events: none;
  font-size: 0.78rem;
  color: var(--ink-2);
  font-variant-numeric: lining-nums;
}

.tick {
  position: absolute;
  background: var(--ink);
}

.tick-x {
  top: 12px;
  width: 1px;
  height: 4px;
}

.tick-y {
  left: 18px;
  height: 1px;
  width: 4px;
}

.tick-label {
  position: absolute;
  line-height: 1;
  white-space: nowrap;
}

.tick-label-x {
  top: 0;
  transform: translateX(-50%);
}

.tick-label-y {
  left: 0;
  transform: translateY(-50%);
}

.map-cap {
  margin: 8px 0 0 22px;
  font-style: italic;
  color: var(--ink-2);
  font-size: 0.95rem;
}

/* --- type ------------------------------------------------------------------ */

.title {
  margin: 0;
  font-weight: 500;
  font-size: 3.4rem;
  line-height: 0.95;
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

.tagline {
  margin: 0.5rem 0 1.2rem;
  font-style: italic;
  font-size: 1.08rem;
  line-height: 1.3;
}

h2 {
  margin: 0 0 0.55rem;
  font-size: 1rem;
  font-weight: 600;
  font-variant-caps: all-small-caps;
  letter-spacing: 0.16em;
  display: flex;
  align-items: center;
  gap: 0.6em;
}

h2::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--rule);
}

.tool,
.margin-ref > section {
  margin-bottom: 1.25rem;
}

.hint,
.footnote,
.note,
.msg {
  margin: 0.4rem 0 0;
  font-size: 0.9rem;
  line-height: 1.3;
  color: var(--ink-2);
}

.msg {
  color: var(--accent);
  font-style: italic;
}

.msg:empty,
.note:empty {
  display: none;
}

kbd {
  font-family: inherit;
  font-variant-caps: all-small-caps;
  letter-spacing: 0.06em;
  border: 1px solid var(--rule);
  padding: 0 0.25em;
}

/* --- instruments ----------------------------------------------------------- */

.btn {
  font: inherit;
  font-size: 0.98rem;
  font-variant-caps: all-small-caps;
  letter-spacing: 0.1em;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--ink);
  border-radius: 0;
  padding: 0.28em 0.8em 0.36em;
  cursor: pointer;
  line-height: 1.1;
}

.btn:hover {
  background: var(--ink);
  color: var(--btn-ink);
}

.btn-primary {
  background: var(--ink);
  color: var(--btn-ink);
  min-width: 5.4em;
}

.btn-primary:hover {
  background: var(--accent);
  border-color: var(--accent);
}

.btn-primary[aria-pressed="true"] {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--btn-ink);
}

.btn-quiet {
  border-color: var(--rule);
}

.btn:disabled {
  opacity: 0.5;
  cursor: progress;
}

.btn:focus-visible,
.stamp input:focus-visible + span,
input[type="range"]:focus-visible,
input[type="text"]:focus-visible,
a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.time-row,
.export-row,
.seed-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.stamps {
  display: flex;
  gap: 8px;
  margin-bottom: 0.7rem;
}

.stamp {
  position: relative;
  cursor: pointer;
}

.stamp input {
  position: absolute;
  opacity: 0;
  width: 1px;
  height: 1px;
}

.stamp span {
  display: inline-block;
  padding: 0.2em 0.75em 0.3em;
  border: 1px solid var(--rule);
  font-variant-caps: all-small-caps;
  letter-spacing: 0.12em;
  color: var(--ink-2);
}

.stamp input:checked + span {
  color: var(--accent);
  border: 3px double var(--accent);
  padding: 0.1em 0.65em 0.2em;
  font-weight: 600;
  transform: rotate(-1.5deg);
}

.stamp-small span {
  font-variant-numeric: lining-nums;
}

.rule-field {
  display: block;
  margin: 0.4rem 0 0.6rem;
}

.rule-label {
  display: flex;
  justify-content: space-between;
  font-variant-caps: all-small-caps;
  letter-spacing: 0.1em;
}

.rule-label output {
  font-variant-caps: normal;
  letter-spacing: 0;
  font-style: italic;
  color: var(--ink-2);
  font-variant-numeric: lining-nums;
}

/* Range inputs drawn as a ruler with a pointer. */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 20px;
  margin: 2px 0 0;
  background:
    linear-gradient(var(--ink), var(--ink)) 0 100% / 100% 1px no-repeat,
    repeating-linear-gradient(to right, var(--ink) 0 1px, transparent 1px 10%) 0 100% / calc(100% - 1px) 8px no-repeat,
    repeating-linear-gradient(to right, var(--rule) 0 1px, transparent 1px 2%) 0 100% / calc(100% - 1px) 4px no-repeat;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-runnable-track {
  height: 20px;
  background: transparent;
}

input[type="range"]::-moz-range-track {
  height: 20px;
  background: transparent;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 13px;
  height: 14px;
  margin-top: 0;
  background: var(--accent);
  clip-path: polygon(0 0, 100% 0, 50% 100%);
  border: 0;
}

input[type="range"]::-moz-range-thumb {
  width: 13px;
  height: 14px;
  background: var(--accent);
  clip-path: polygon(0 0, 100% 0, 50% 100%);
  border: 0;
  border-radius: 0;
}

.years {
  margin: 0.9rem 0 0;
  display: flex;
  align-items: baseline;
  gap: 0.35em;
}

.years-n {
  font-size: 2.6rem;
  line-height: 1;
  font-weight: 500;
  font-variant-numeric: lining-nums tabular-nums;
}

.years-u {
  font-variant-caps: all-small-caps;
  letter-spacing: 0.12em;
  font-size: 1.05rem;
}

.ref-mark {
  color: var(--accent);
  text-decoration: none;
  margin-left: 0.1em;
}

input[type="text"] {
  font: inherit;
  font-variant-numeric: lining-nums;
  width: 6.5em;
  padding: 0.18em 0.4em;
  color: var(--ink);
  background: transparent;
  border: 0;
  border-bottom: 1px solid var(--ink);
  border-radius: 0;
}

input[aria-invalid="true"] {
  border-bottom-color: var(--accent);
  border-bottom-width: 2px;
}

.field-label {
  display: block;
  font-variant-caps: all-small-caps;
  letter-spacing: 0.1em;
  margin-bottom: 0.2rem;
  padding: 0;
}

.grid-set {
  border: 0;
  margin: 0.8rem 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}

.grid-set legend {
  float: left;
  margin: 0 0.4rem 0 0;
}

.export-row {
  margin-top: 0.8rem;
}

/* --- legend ------------------------------------------------------------------ */

.legend,
.symbols {
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 0.92rem;
}

.legend {
  display: grid;
  grid-template-columns: 1fr;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
  margin-bottom: 0.7rem;
}

.legend li {
  display: flex;
  align-items: center;
  gap: 0.6em;
  line-height: 1.05;
  font-size: 0.88rem;
  font-variant-numeric: lining-nums tabular-nums;
}

.legend .sw {
  width: 30px;
  height: 13px;
  border-left: 1px solid var(--ink);
  border-right: 1px solid var(--ink);
  flex: none;
}

.symbols li {
  display: flex;
  align-items: center;
  gap: 0.6em;
  margin: 0.22rem 0;
  line-height: 1.2;
}

.sym {
  width: 30px;
  height: 12px;
  flex: none;
  position: relative;
}

.sym-river::before {
  content: "";
  position: absolute;
  left: 1px;
  right: 1px;
  top: 50%;
  height: 3px;
  margin-top: -1.5px;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--river) 0 100%);
  clip-path: polygon(0 35%, 100% 0, 100% 100%, 0 65%);
}

.sym-sea {
  background:
    linear-gradient(var(--coast), var(--coast)) 0 0 / 100% 1px no-repeat,
    linear-gradient(var(--waterline), var(--waterline)) 0 3px / 100% 1px no-repeat,
    linear-gradient(color-mix(in srgb, var(--waterline) 60%, transparent), color-mix(in srgb, var(--waterline) 60%, transparent)) 0 7px / 100% 1px no-repeat,
    var(--sea);
}

.sym-contour::before,
.sym-index::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  border-top: 1px solid var(--contour);
  opacity: 0.7;
}

.sym-index::before {
  border-top-width: 2px;
  margin-top: -1px;
  opacity: 1;
}

.sym-newland {
  background: var(--silt);
  outline: 1px solid var(--hair);
}

.sym-shoal {
  background-color: var(--shoal);
  background-image: radial-gradient(circle, var(--waterline) 0 0.7px, transparent 1px);
  background-size: 3.4px 3.4px;
  outline: 1px solid var(--hair);
}

.sym-alluvium {
  background-image: radial-gradient(circle, var(--stipple) 0 1.1px, transparent 1.4px);
  background-size: 5px 5px;
  outline: 1px solid var(--hair);
}

.orient {
  display: flex;
  align-items: flex-end;
  gap: 16px;
  margin: 0.2rem 0 1.2rem;
}

.north {
  width: 28px;
  height: 45px;
  flex: none;
}

.north-open {
  fill: none;
  stroke: var(--ink);
  stroke-width: 1.4;
  stroke-linejoin: round;
}

.north-fill {
  fill: var(--ink);
}

.north-n {
  fill: var(--ink);
  font: 600 14px "EB Garamond", Georgia, serif;
}

.scale-wrap {
  flex: 1;
  min-width: 0;
}

.scale {
  color: var(--ink);
}

.scale-cap {
  margin: 2px 0 0;
  font-size: 0.8rem;
  font-style: italic;
  line-height: 1.2;
  color: var(--ink-2);
}

.scale svg {
  display: block;
  overflow: visible;
}

.scale text {
  fill: var(--ink);
  font: 12px "EB Garamond", Georgia, serif;
  font-variant-numeric: lining-nums;
}

.scale .sc-fill {
  fill: var(--ink);
  stroke: var(--ink);
}

.scale .sc-open {
  fill: var(--sheet);
  stroke: var(--ink);
}

.scale .sc-cap {
  fill: var(--ink-2);
  font-style: italic;
}

/* --- title block -------------------------------------------------------------- */

.title-block {
  margin: 0 0 0.8rem;
  border: 1.5px solid var(--ink);
  outline: 1px solid var(--ink);
  outline-offset: 2px;
  font-size: 0.86rem;
  line-height: 1.25;
}

.title-block > div {
  display: grid;
  grid-template-columns: 5.2em 1fr;
  gap: 0.5em;
  padding: 0.24em 0.5em;
  border-top: 1px solid var(--rule);
}

.title-block > div:first-child {
  border-top: 0;
}

.title-block dt {
  font-variant-caps: all-small-caps;
  letter-spacing: 0.1em;
  color: var(--ink-2);
}

.title-block dd {
  margin: 0;
  font-variant-numeric: lining-nums;
}

.tb-head {
  background: var(--ink);
  color: var(--btn-ink);
}

.tb-head dt {
  color: var(--btn-ink);
}

.tb-name {
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.theme-btn {
  font-size: 0.9rem;
}

/* --- narrower sheets ---------------------------------------------------------- */

@media (max-width: 1180px) {
  .sheet-body {
    grid-template-columns: minmax(0, auto) 250px;
    grid-template-rows: auto auto 1fr;
    grid-template-areas:
      "map mast"
      "map tools"
      "map ref";
  }
}

@media (max-width: 780px) {
  body {
    font-size: 16px;
  }
  .sheet {
    margin: 0;
    padding: 12px 14px;
  }
  .sheet-head {
    font-size: 0.85rem;
    letter-spacing: 0.1em;
  }
  .sheet-body {
    display: flex;
    flex-direction: column;
    gap: 14px;
  }
  .map-frame {
    --size: 100%;
    padding: 14px 0 0 18px;
  }
  .tick-x {
    top: 10px;
  }
  .tick-y {
    left: 14px;
  }
  .map-cap {
    margin-left: 18px;
  }
  .title {
    font-size: 2.5rem;
  }
  .tagline {
    margin-bottom: 0;
  }
}