/* Unit converter.
 *
 * One column, one input, one list of answers. The look follows the portfolio's
 * "Golden Hour" palette (warm orange on a cool off-white) but the tokens are
 * declared here, because a web-project is self-contained and never imports the
 * site's global CSS.
 *
 * Two rules shape most of what follows:
 *   - numbers are the content, so they get the size, the weight and
 *     `tabular-nums`, and everything else stays quiet around them
 *   - the input has to stay reachable while a long list of answers scrolls, so
 *     it sticks to the top on every screen
 */

:root {
  color-scheme: light dark;

  --bg: #eef0f5;
  --bg-wash-a: rgba(220, 90, 0, 0.07);
  --bg-wash-b: rgba(67, 28, 93, 0.06);
  --surface: #ffffff;
  --surface-sunk: #f4f5f8;
  --border: rgba(20, 20, 34, 0.09);
  --border-strong: rgba(20, 20, 34, 0.16);

  --text: #141422;
  --text-body: #2e2e3e;
  --muted: #6b6b80;

  --accent: rgb(220 90 0);
  --accent-rgb: 220, 90, 0;
  --accent-ink: rgb(150 58 0);
  --accent-soft: rgba(220, 90, 0, 0.1);

  --shadow-sm: 0 1px 3px rgba(20, 20, 34, 0.06);
  --shadow-md: 0 6px 24px rgba(20, 20, 34, 0.09);
  --shadow-lg: 0 16px 48px rgba(20, 20, 34, 0.14);

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 999px;

  --ease: cubic-bezier(0.25, 1, 0.5, 1);
  --fast: 140ms;
  --normal: 280ms;

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --measure: 40rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #101017;
    --bg-wash-a: rgba(255, 138, 61, 0.09);
    --bg-wash-b: rgba(128, 92, 200, 0.08);
    --surface: #1a1a24;
    --surface-sunk: #14141d;
    --border: rgba(255, 255, 255, 0.09);
    --border-strong: rgba(255, 255, 255, 0.18);

    --text: #f3f3f8;
    --text-body: #dcdce6;
    --muted: #9a9aae;

    --accent: #ff8f45;
    --accent-rgb: 255, 143, 69;
    --accent-ink: #ffb182;
    --accent-soft: rgba(255, 143, 69, 0.14);

    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 6px 24px rgba(0, 0, 0, 0.45);
    --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.55);
  }
}

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

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

/* The browser hides a `hidden` element with `display: none`, and any `display`
   an author writes wins over it. `app.js` shows and hides most of this page
   through that attribute, so without this rule a hidden `.chips` or
   `.text-button` stays on screen. It showed as a "Show 0 more units" button
   under a category that had nothing more to show. */
[hidden] {
  display: none !important;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.55;
  color: var(--text-body);
  background:
    radial-gradient(1100px 600px at 15% -10%, var(--bg-wash-a), transparent 60%),
    radial-gradient(900px 500px at 90% 5%, var(--bg-wash-b), transparent 55%),
    var(--bg);
  background-attachment: fixed;
}

h1,
h2 {
  color: var(--text);
  line-height: 1.15;
  margin: 0;
}

a {
  color: var(--accent-ink);
}

button {
  font: inherit;
  color: inherit;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 6px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 20;
  padding: 0.6rem 1rem;
  background: var(--surface);
  border-radius: 0 0 var(--radius-sm) 0;
}

.skip-link:focus {
  left: 0;
}

.page {
  max-width: var(--measure);
  margin: 0 auto;
  padding: 0 1rem 3rem;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* --- masthead ------------------------------------------------------------ */

.masthead {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  padding: 2.25rem 0 1.25rem;
}

h1 {
  font-size: clamp(1.6rem, 6vw, 2.1rem);
  letter-spacing: -0.02em;
  font-weight: 660;
}

.tagline {
  margin: 0.35rem 0 0;
  color: var(--muted);
  font-size: 0.95rem;
  max-width: 44ch;
}

.lang {
  display: flex;
  gap: 2px;
  padding: 3px;
  background: var(--surface-sunk);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  flex-shrink: 0;
}

.lang button {
  border: 0;
  background: transparent;
  color: var(--muted);
  padding: 0.3rem 0.7rem;
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--fast) var(--ease), color var(--fast) var(--ease);
}

.lang button[aria-pressed="true"] {
  background: var(--surface);
  color: var(--text);
  box-shadow: var(--shadow-sm);
}

/* --- the input ----------------------------------------------------------- */
/* Sticky, because the answer list can be long and the thing you want to edit
   is always the line you typed. */

.field-wrap {
  position: sticky;
  top: 0;
  z-index: 10;
  padding: 0.5rem 1rem 0.75rem;
  margin: 0 -1rem;
}

/* The bar carries the page's own background, pinned to the viewport exactly as
   the body's is, so the two line up at every scroll position. A gradient of a
   flat colour cannot do that: it shows as a paler rectangle over the washes. */
.field-wrap::before {
  content: "";
  position: absolute;
  inset: 0 0 -14px;
  z-index: -1;
  background:
    radial-gradient(1100px 600px at 15% -10%, var(--bg-wash-a), transparent 60%),
    radial-gradient(900px 500px at 90% 5%, var(--bg-wash-b), transparent 55%),
    var(--bg);
  background-attachment: fixed;
  mask-image: linear-gradient(#000 calc(100% - 14px), transparent);
  -webkit-mask-image: linear-gradient(#000 calc(100% - 14px), transparent);
}

.field {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.55rem 0.6rem 0.55rem 0.9rem;
  background: var(--surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  transition: border-color var(--fast) var(--ease), box-shadow var(--fast) var(--ease);
}

.field:focus-within {
  border-color: var(--accent);
  box-shadow: var(--shadow-md), 0 0 0 4px var(--accent-soft);
}

.field-icon {
  width: 22px;
  height: 22px;
  flex-shrink: 0;
  fill: none;
  stroke: var(--muted);
  stroke-width: 1.7;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.field:focus-within .field-icon {
  stroke: var(--accent);
}

#query {
  flex: 1;
  min-width: 0;
  border: 0;
  background: transparent;
  padding: 0.35rem 0;
  font-family: inherit;
  font-size: 1.35rem;
  font-weight: 560;
  letter-spacing: -0.01em;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

#query:focus {
  outline: none;
}

#query::placeholder {
  color: var(--muted);
  font-weight: 450;
  opacity: 0.75;
}

.icon-button {
  flex-shrink: 0;
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border: 0;
  border-radius: var(--radius-full);
  background: var(--surface-sunk);
  cursor: pointer;
  transition: background var(--fast) var(--ease), transform var(--fast) var(--ease);
}

.icon-button svg {
  width: 15px;
  height: 15px;
  fill: none;
  stroke: var(--muted);
  stroke-width: 2;
  stroke-linecap: round;
}

.icon-button:hover {
  background: var(--accent-soft);
}

.icon-button:hover svg {
  stroke: var(--accent);
}

/* --- suggestions --------------------------------------------------------- */

/* Floating over the answers rather than pushing them down: the list opens and
   closes on almost every keystroke, and content that jumps that often is
   unreadable. `.field-wrap` is sticky, which already makes it the box this is
   positioned against. */
.suggestions {
  position: absolute;
  left: 1rem;
  right: 1rem;
  top: 100%;
  z-index: 12;
  list-style: none;
  margin: -0.35rem 0 0;
  padding: 0.3rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  max-height: min(50vh, 320px);
  overflow-y: auto;
  overscroll-behavior: contain;
}

.suggestion {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  padding: 0.55rem 0.7rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
}

.suggestion[aria-selected="true"],
.suggestion:hover {
  background: var(--accent-soft);
}

.suggestion-sym {
  font-weight: 680;
  color: var(--text);
  font-variant-numeric: tabular-nums;
  min-width: 3.2rem;
}

.suggestion-name {
  color: var(--text-body);
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.suggestion-cat {
  font-size: 0.75rem;
  color: var(--muted);
  flex-shrink: 0;
}

/* --- what the page understood -------------------------------------------- */

.reading {
  margin: 0 0 0.9rem;
  font-size: 0.85rem;
  color: var(--muted);
  padding-inline: 0.2rem;
}

.reading strong {
  color: var(--text-body);
  font-weight: 620;
}

.reading.is-warning {
  color: var(--accent-ink);
}

/* --- headings ------------------------------------------------------------ */

.section-heading {
  font-size: 0.75rem;
  font-weight: 680;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 1.6rem 0 0.6rem;
  padding-inline: 0.2rem;
}

.results .section-heading:first-child {
  margin-top: 0.2rem;
}

/* --- the target a person asked for --------------------------------------- */

.target-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2px;
  width: 100%;
  text-align: left;
  padding: 1.05rem 1.15rem;
  margin-bottom: 0.9rem;
  background: var(--surface);
  border: 1px solid var(--accent);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-md), 0 0 0 4px var(--accent-soft);
  cursor: pointer;
  animation: rise var(--normal) var(--ease) both;
}

.target-card .value {
  font-size: clamp(1.7rem, 7vw, 2.3rem);
}

.target-card .sym {
  font-size: 1.1rem;
  color: var(--accent-ink);
}

/* --- the answers --------------------------------------------------------- */

.rows {
  list-style: none;
  margin: 0;
  padding: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.rows:empty {
  display: none;
}

.row {
  display: flex;
  align-items: center;
  border-top: 1px solid var(--border);
}

.row:first-child {
  border-top: 0;
}

.row-main {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 1px;
  padding: 0.7rem 0.5rem 0.75rem 1.05rem;
  border: 0;
  background: transparent;
  text-align: left;
  cursor: pointer;
  transition: background var(--fast) var(--ease);
}

.row-main:hover,
.target-card:hover {
  background: var(--accent-soft);
}

.value-line {
  display: flex;
  align-items: baseline;
  gap: 0.4rem;
  max-width: 100%;
}

.value {
  font-size: 1.3rem;
  font-weight: 650;
  color: var(--text);
  letter-spacing: -0.015em;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  flex-shrink: 1;
}

.about {
  min-width: 0;
  max-width: 100%;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.sym {
  font-size: 0.95rem;
  font-weight: 620;
  color: var(--muted);
  white-space: nowrap;
}

.about-note {
  font-size: 0.75rem;
  color: var(--muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.compound {
  font-variant-numeric: tabular-nums;
  color: var(--accent-ink);
}

.row-swap {
  flex-shrink: 0;
  display: grid;
  place-items: center;
  width: 44px;
  align-self: stretch;
  border: 0;
  border-left: 1px solid var(--border);
  background: transparent;
  cursor: pointer;
  transition: background var(--fast) var(--ease);
}

.row-swap svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: var(--muted);
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.row-swap:hover {
  background: var(--accent-soft);
}

.row-swap:hover svg {
  stroke: var(--accent);
}

.text-button {
  display: block;
  margin: 0.7rem auto 0;
  padding: 0.45rem 1rem;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-full);
  background: transparent;
  color: var(--text-body);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--fast) var(--ease), border-color var(--fast) var(--ease);
}

.text-button:hover {
  background: var(--accent-soft);
  border-color: var(--accent);
}

.note {
  margin: 0.9rem 0 0;
  font-size: 0.78rem;
  color: var(--muted);
  padding-inline: 0.2rem;
}

/* --- chips: examples, recents, categories -------------------------------- */

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  padding-inline: 0.2rem;
}

.chips-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(9.5rem, 1fr));
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  background: var(--surface);
  color: var(--text-body);
  font-size: 0.9rem;
  font-weight: 550;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--fast) var(--ease), transform var(--fast) var(--ease), background var(--fast) var(--ease);
}

.chip:hover {
  border-color: var(--accent);
  transform: translateY(-1px);
}

.chip-code {
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.chip-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  flex-shrink: 0;
  background: hsl(var(--hue) 58% 48%);
}

.chip-category {
  justify-content: flex-start;
  border-radius: var(--radius-md);
}

.prompt-hint {
  margin: 0 0 0.7rem;
  color: var(--muted);
  font-size: 0.9rem;
  padding-inline: 0.2rem;
}

/* --- footer -------------------------------------------------------------- */

.footer {
  margin-top: auto;
  padding-top: 2.5rem;
  font-size: 0.78rem;
  color: var(--muted);
  text-align: center;
}

.footer p {
  margin: 0.35rem 0;
}

.privacy {
  max-width: 44ch;
  margin-inline: auto;
}

/* --- toast --------------------------------------------------------------- */

.toast {
  position: fixed;
  left: 50%;
  bottom: 1.25rem;
  transform: translate(-50%, 1.5rem);
  z-index: 30;
  max-width: calc(100vw - 2rem);
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius-full);
  background: var(--text);
  color: var(--surface);
  font-size: 0.85rem;
  font-weight: 560;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--normal) var(--ease), transform var(--normal) var(--ease);
}

.toast.is-shown {
  opacity: 1;
  transform: translate(-50%, 0);
}

/* --- motion -------------------------------------------------------------- */

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(6px);
  }
}

.results:not([hidden]) .rows {
  animation: rise var(--normal) var(--ease) both;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 1ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 1ms !important;
  }
}

/* --- small screens ------------------------------------------------------- */

@media (max-width: 30rem) {
  .masthead {
    padding: 1.5rem 0 0.9rem;
  }

  .tagline {
    font-size: 0.88rem;
  }

  #query {
    font-size: 1.2rem;
  }

  .row-main {
    gap: 0.7rem;
    padding-left: 0.85rem;
  }

  .value {
    font-size: 1.15rem;
  }

  .chips-grid {
    grid-template-columns: repeat(auto-fill, minmax(8rem, 1fr));
  }
}

/* Wide screens get a two-column answer list, because a long single column
   makes a person scroll for something that already fits on the screen. */
@media (min-width: 56rem) {
  :root {
    --measure: 54rem;
  }

  .rows {
    display: grid;
    grid-template-columns: 1fr 1fr;
  }

  .row:nth-child(2) {
    border-top: 0;
  }

  .row:nth-child(even) {
    border-left: 1px solid var(--border);
  }
}