/* SPDX-License-Identifier: GPL-3.0-or-later */
/* Copyright (C) 2026 Darren Chi */
/* BX Tacho web: a cool, quiet page around the device's own OLED look. */

:root {
  --paper: #e9edf1;       /* stadium grey */
  --surface: #ffffff;
  --ink: #18202b;
  --muted: #5b6675;
  --line: #cdd4dc;
  --oled: #000000;        /* the real panel is black */
  --pixel: #cfe8ff;       /* its pixel colour */
  --pixel-dim: #7d97b0;
  --bezel: #232b36;
  --signal: #2b54e0;      /* actions, focus, the newest shot */
  --signal-soft: rgba(43, 84, 224, 0.1);
  --ok: #1f7a46;
  --warn: #9a5d0c;
  --bad: #b8312a;

  --sans: 'Archivo', system-ui, sans-serif;
  --mono: 'JetBrains Mono', ui-monospace, monospace;

  /* Type scale, ratio 1.25 from a 16 px body */
  --t-small: 0.8125rem;
  --t-body: 1rem;
  --t-lead: 1.25rem;
  --t-h2: 1.5625rem;
  --t-h1: 2.4375rem;
  --t-stat: 2.4375rem;

  --radius: 10px;
  --gutter: clamp(16px, 3vw, 32px);
}

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

/* Chinese: Archivo keeps the Latin letters and digits, the system's CJK font the rest */
:root:lang(zh-Hant) {
  --sans: 'Archivo', 'PingFang TC', 'Microsoft JhengHei', 'Noto Sans TC', 'Noto Sans CJK TC', system-ui, sans-serif;
}

:root:lang(zh-Hans) {
  --sans: 'Archivo', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', 'Noto Sans CJK SC', system-ui, sans-serif;
}

:root:lang(ja) {
  --sans: 'Archivo', 'Hiragino Sans', 'Hiragino Kaku Gothic ProN', 'Yu Gothic UI', 'Meiryo', 'Noto Sans JP', 'Noto Sans CJK JP', system-ui, sans-serif;
}

/* CJK text has no word spaces to stretch or tighten */
:lang(zh) .title,
:lang(ja) .title {
  letter-spacing: 0.02em;
}

html {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 100%;
  line-height: 1.5;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--paper);
}

main {
  flex: 1;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--gutter) 48px;
}

code {
  font-family: var(--mono);
  font-size: 0.875em;
}

button {
  font: inherit;
  color: inherit;
}

:focus-visible {
  outline: 3px solid var(--signal);
  outline-offset: 2px;
}

[hidden] {
  display: none !important;
}

/* ---------------------------------------------------------------- header */

.top {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px var(--gutter) 28px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: end;
  gap: 16px 32px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  line-height: 0;
  text-decoration: none;
}

.brand__icon {
  display: block;
  width: 44px;
  height: 44px;
}

.brand__plate {
  display: block;
  padding: 10px 12px;
  background: var(--oled);
  border-radius: 8px;
  border: 1px solid var(--bezel);
}

.switch {
  display: flex;
  gap: 28px;
  align-self: end;
}

.switch__tab {
  background: none;
  border: 0;
  padding: 0 0 6px;
  font-size: var(--t-lead);
  font-weight: 700;
  font-stretch: 112%;
  color: var(--muted);
  border-bottom: 4px solid transparent;
  cursor: pointer;
}

.switch__tab[aria-selected='true'] {
  color: var(--ink);
  border-bottom-color: var(--signal);
}

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

.link {
  margin: 0;
  justify-self: end;
  font-size: var(--t-small);
  color: var(--muted);
  display: flex;
  align-items: center;
  gap: 8px;
}

.link::before {
  content: '';
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--line);
}

.link[data-state='on']::before {
  background: var(--ok);
}

/* ---------------------------------------------------------------- shared */

.title {
  margin: 0;
  font-size: var(--t-h1);
  font-weight: 800;
  font-stretch: 125%;
  line-height: 1.05;
  letter-spacing: -0.01em;
}

.title--small {
  font-size: var(--t-h2);
  font-weight: 750;
}

.body {
  margin: 0;
  color: var(--muted);
  max-width: 60ch;
}

/* Which BX Tacho is connected: under the Bluetooth tab's heading */
.device-line {
  margin-top: 6px;
  font-variant-numeric: tabular-nums;
}

.body--wide {
  max-width: none;
}

.aside-text {
  margin: 0;
  font-size: var(--t-small);
  color: var(--muted);
}

.bar-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px 20px;
  flex-wrap: wrap;
}

.bar-row__end {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.note {
  margin: 14px 0 0;
  padding: 10px 14px;
  border-left: 3px solid var(--warn);
  background: var(--surface);
  color: var(--ink);
  font-size: var(--t-small);
  max-width: 70ch;
}

.note[data-tone='bad'] {
  border-left-color: var(--bad);
}

.note[data-tone='info'] {
  border-left-color: var(--signal);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 0 18px;
  border-radius: var(--radius);
  border: 1.5px solid var(--ink);
  background: var(--surface);
  font-weight: 650;
  cursor: pointer;
}

.btn:hover:not(:disabled) {
  background: var(--paper);
}

.btn--primary {
  background: var(--signal);
  border-color: var(--signal);
  color: #fff;
}

.btn--primary:hover:not(:disabled) {
  background: #2246c4;
}

.btn--wide {
  width: 100%;
}

.btn--danger,
.btn--primary.btn--danger {
  background: var(--bad);
  border-color: var(--bad);
  color: #fff;
}

.btn--primary.btn--danger:hover:not(:disabled) {
  background: #9c2822;
}

.btn:disabled {
  cursor: not-allowed;
  opacity: 0.45;
}

/* The device-like black panels */
.screen {
  background: var(--oled);
  color: var(--pixel);
  border: 1px solid var(--bezel);
  border-radius: 14px;
  position: relative;
}

/* ---------------------------------------------------------------- USB tab */

/* Console on top, firmware update below it */
.usb {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 40px;
}

.console {
  display: grid;
  gap: 16px;
  min-width: 0;
}

.screen--term {
  height: min(62vh, 520px);
  min-height: 320px;
  padding: 14px 6px 14px 16px;
  overflow: hidden;
}

.term {
  height: 100%;
}

.term .xterm-viewport {
  background: transparent !important;
}

.term__empty {
  position: absolute;
  inset: 0;
  margin: 0;
  display: grid;
  place-items: center;
  padding: 24px;
  text-align: center;
  color: var(--pixel-dim);
  font-size: var(--t-body);
  pointer-events: none;
}

.quick {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.chip {
  min-height: 36px;
  padding: 0 14px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--surface);
  font-family: var(--mono);
  font-size: 0.875rem;
  cursor: pointer;
}

.chip:hover:not(:disabled) {
  border-color: var(--ink);
}

.chip:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.chip--quiet {
  font-family: var(--sans);
  background: none;
  border-color: transparent;
  color: var(--muted);
  margin-left: auto;
}

/* Below the console, one column at every width: heading and text, then the controls */
.flash {
  display: grid;
  gap: 16px;
  border-top: 1px solid var(--line);
  padding-top: 32px;
}

/* The controls span the page; the text keeps a readable line length */
.flash__intro,
.flash__controls {
  display: grid;
  gap: 16px;
  min-width: 0;
}

.drop {
  position: relative;
  display: grid;
  gap: 2px;
  padding: 22px 18px;
  border: 1.5px dashed var(--muted);
  border-radius: var(--radius);
  background: var(--surface);
  cursor: pointer;
  text-align: center;
}

.drop input {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
}

.drop:focus-within {
  outline: 3px solid var(--signal);
  outline-offset: 2px;
}

.drop[data-over='true'] {
  border-color: var(--signal);
  background: var(--signal-soft);
}

.drop__label {
  font-weight: 700;
}

.drop__hint {
  font-size: var(--t-small);
  color: var(--muted);
}

.fw {
  border-left: 3px solid var(--signal);
  padding: 2px 0 2px 12px;
}

.fw[data-kind='full'] {
  border-left-color: var(--warn);
}

.fw[data-kind='invalid'] {
  border-left-color: var(--bad);
}

.fw__name {
  margin: 0;
  font-weight: 700;
}

.fw__detail {
  margin: 2px 0 0;
  font-size: var(--t-small);
  color: var(--muted);
}

/* The file's SHA-256, to compare with a release's SHA256SUMS.txt */
.fw__sum {
  margin: 4px 0 0;
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--muted);
  overflow-wrap: anywhere;
  user-select: all;
}

.adv {
  border-top: 1px solid var(--line);
  padding-top: 12px;
}

.adv__summary {
  cursor: pointer;
  font-weight: 650;
  font-size: var(--t-small);
  color: var(--muted);
  width: fit-content;
}

.adv[open] .adv__summary {
  margin-bottom: 10px;
  color: var(--ink);
}

.check {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  cursor: pointer;
  margin-bottom: 6px;
}

.adv__warn {
  margin: 0;
  font-size: var(--t-small);
  font-weight: 600;
  color: var(--bad);
}

.check input {
  width: 18px;
  height: 18px;
  accent-color: var(--bad);
  margin: 0;
}

.fw[data-erase='true'] {
  border-left-color: var(--bad);
}

.progress {
  display: grid;
  gap: 6px;
}

.progress__track {
  height: 8px;
  border-radius: 4px;
  background: var(--line);
  overflow: hidden;
}

.progress__fill {
  height: 100%;
  width: 0;
  background: var(--signal);
  transition: width 120ms linear;
}

.progress__text {
  margin: 0;
  font-size: var(--t-small);
  color: var(--muted);
}

.progress__text[data-tone='ok'] {
  color: var(--ok);
  font-weight: 700;
}

.progress__text[data-tone='bad'] {
  color: var(--bad);
}

.fw-log {
  margin: 0;
  max-height: 180px;
  overflow: auto;
  padding: 10px 12px;
  border-radius: 8px;
  background: var(--oled);
  color: var(--pixel-dim);
  font-family: var(--mono);
  font-size: 0.75rem;
  line-height: 1.45;
  white-space: pre-wrap;
}

/* ---------------------------------------------------------------- Bluetooth tab */

.hero {
  margin-top: 24px;
  display: grid;
  grid-template-columns: minmax(0, 1.7fr) minmax(220px, 1fr);
  gap: 32px;
  align-items: stretch;
}

.screen--readout {
  padding: 22px 26px 20px;
  display: grid;
  gap: 14px;
  align-content: space-between;
  min-height: 230px;
}

.screen__label,
.screen__foot {
  margin: 0;
  color: var(--pixel-dim);
  font-size: var(--t-small);
}

.screen__foot {
  color: var(--pixel);
}

.readout {
  display: flex;
  align-items: flex-end;
  gap: 14px;
  min-height: 1px;
}

.readout__digits {
  display: block;
  max-width: 100%;
}

.readout__unit {
  color: var(--pixel-dim);
  font-size: var(--t-lead);
  font-weight: 600;
  padding-bottom: 4px;
}

.stats {
  margin: 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 22px 24px;
  align-content: center;
}

.stat {
  border-top: 1px solid var(--line);
  padding-top: 10px;
}

.stat dt {
  font-size: var(--t-small);
  color: var(--muted);
}

.stat dd {
  margin: 2px 0 0;
  font-size: var(--t-stat);
  font-weight: 800;
  font-stretch: 118%;
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}

.stat dd[data-tone='ok'] {
  color: var(--ok);
}

.stat dd[data-tone='warn'] {
  color: var(--warn);
}

.block {
  margin-top: 48px;
  display: grid;
  gap: 16px;
}

.seg {
  display: inline-flex;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 3px;
  background: var(--surface);
}

.seg__btn {
  border: 0;
  background: none;
  padding: 6px 14px;
  border-radius: 6px;
  font-size: var(--t-small);
  font-weight: 600;
  color: var(--muted);
  cursor: pointer;
}

.seg__btn[aria-pressed='true'] {
  background: var(--ink);
  color: #fff;
}

.seg__btn:disabled {
  cursor: not-allowed;
  opacity: 0.45;
}

/* A setting under a console: label, then its choices */
.setting {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.setting__label {
  font-size: var(--t-small);
  font-weight: 600;
  color: var(--muted);
}

/* The calibration buttons under a console, shown while Calibration is on */
.cal {
  display: grid;
  gap: 8px;
}

.cal .aside-text {
  margin: 0;
}

.curve {
  margin: 0;
  background: var(--surface);
  border-radius: var(--radius);
  padding: 12px 12px 8px;
}

.curve__svg {
  display: block;
  width: 100%;
  height: auto;
  min-height: 180px;
}

.curve__caption {
  padding: 4px 6px 4px;
  font-size: var(--t-small);
  color: var(--muted);
}

.chart-grid line {
  stroke: var(--line);
  stroke-width: 1;
}

.chart-grid text {
  fill: var(--muted);
  font-family: var(--sans);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
}

.chart-grid .chart-axis {
  fill: var(--ink);
  font-size: 13px;
  font-weight: 600;
}

.chart-line {
  fill: none;
  stroke: var(--signal);
  stroke-width: 2.5;
  stroke-linejoin: round;
}

.chart-area {
  fill: var(--signal-soft);
}

.chart-dots circle {
  fill: var(--signal);
}

.chart-peak {
  fill: none;
  stroke: var(--ink);
  stroke-width: 2;
}

.history {
  list-style: none;
  margin: 0;
  padding: 14px 12px 0;
  height: 150px;
  display: flex;
  align-items: flex-end;
  gap: 3px;
  background: var(--surface);
  border-radius: var(--radius);
}

.bar {
  flex: 1 1 0;
  max-width: 28px;
  height: var(--h);
  background: #b3c0cd;
  border-radius: 3px 3px 0 0;
  cursor: default;
}

.bar:hover,
.bar:focus-visible {
  background: var(--ink);
}

.bar--latest {
  background: var(--signal);
}

/* Console over Bluetooth: output above, the command line below it */
.screen--bterm {
  height: min(46vh, 400px);
  min-height: 260px;
}

.cmdline {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
}

.cmdline__prompt {
  font-family: var(--mono);
  font-weight: 600;
  color: var(--muted);
}

.cmdline__input {
  flex: 1 1 auto;
  min-width: 0;
  min-height: 42px;
  padding: 0 12px;
  font: 0.9375rem var(--mono);
  color: var(--ink);
  background: var(--surface);
  border: 1.5px solid var(--line);
  border-radius: var(--radius);
}

.cmdline__input:focus-visible {
  outline: none;
  border-color: var(--signal);
}

.cmdline__input:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* The code dialog (console over Bluetooth) */
.dialog {
  width: min(420px, calc(100vw - 2 * var(--gutter)));
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--surface);
  color: var(--ink);
  box-shadow: 0 20px 60px rgba(24, 32, 43, 0.25);
}

.dialog::backdrop {
  background: rgba(24, 32, 43, 0.45);
}

.dialog__body {
  display: grid;
  gap: 16px;
  padding: 24px;
}

.dialog__body .note {
  margin: 0;
}

.code-input {
  width: 100%;
  min-height: 64px;
  padding: 0 12px;
  font: 600 2rem var(--mono);
  letter-spacing: 0.2em;
  text-align: center;
  color: var(--ink);
  background: var(--paper);
  border: 1.5px solid var(--line);
  border-radius: var(--radius);
}

.code-input:focus-visible {
  outline: none;
  border-color: var(--signal);
}

.dialog__actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
}

.history:empty::before {
  content: attr(data-empty);
  align-self: center;
  margin: 0 auto 40px;
  color: var(--muted);
  font-size: var(--t-small);
}

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

.foot {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px var(--gutter) 28px;
  color: var(--muted);
  font-size: var(--t-small);
}

.foot__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
  border-top: 1px solid var(--line);
  padding-top: 16px;
}

.foot__text {
  margin: 0;
  flex: 1 1 auto;
}

.lang {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.lang__select {
  font: inherit;
  color: var(--ink);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 6px 10px;
  cursor: pointer;
}

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

@media (max-width: 900px) {
  .usb,
  .hero {
    grid-template-columns: minmax(0, 1fr);
  }

  .top {
    grid-template-columns: auto 1fr;
  }

  .switch {
    grid-column: 1 / -1;
    grid-row: 2;
  }

  .link {
    grid-column: 2;
    grid-row: 1;
    align-self: center;
  }
}

@media (max-width: 520px) {
  :root {
    --t-h1: 1.953rem;
    --t-stat: 1.953rem;
  }

  .screen--term {
    height: 58vh;
  }

  .chip--quiet {
    margin-left: 0;
  }

  /* Prompt and input on one row, the buttons on the next */
  .cmdline {
    flex-wrap: wrap;
  }

  .cmdline__input {
    flex-basis: calc(100% - 60px);
  }

  .cmdline .btn {
    flex: 1 1 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .progress__fill {
    transition: none;
  }
}