:root {
  --paper: #f5eee2;
  --paper-2: #efe4d5;
  --ink: #20262b;
  --muted: #637071;
  --oxide: #b85c38;
  --teal: #286a73;
  --green: #607f65;
  --gold: #dfb960;
  --line: #d9c9b8;
  --night: #1e272b;
  --cream: #fff8ea;
  color-scheme: light;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: var(--paper);
  color: var(--ink);
  font-family: "华文隶书", "STLiti", "LiSu", "Songti SC", serif;
}

button,
input,
select {
  font: inherit;
}

.app-shell {
  display: grid;
  grid-template-columns: 332px minmax(0, 1fr);
  min-height: 100vh;
}

.library-panel {
  background: #241f1b;
  color: var(--cream);
  padding: 28px 22px;
  display: flex;
  flex-direction: column;
  gap: 22px;
  border-right: 1px solid rgba(255,255,255,.08);
}

.brand-row {
  display: flex;
  align-items: center;
  gap: 14px;
}

.seal {
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  background: var(--oxide);
  color: var(--cream);
  font-size: 30px;
  font-weight: 700;
}

.eyebrow {
  margin: 0 0 6px;
  color: var(--oxide);
  font-family: Arial, sans-serif;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 0;
  font-size: 26px;
}

h2 {
  max-width: 780px;
  margin-bottom: 10px;
  font-size: 40px;
  line-height: 1.08;
}

h3 {
  margin-bottom: 8px;
  font-size: 26px;
  line-height: 1.12;
}

.search-box {
  display: grid;
  gap: 8px;
  color: rgba(255,255,255,.72);
  font-size: 14px;
}

.search-box input {
  width: 100%;
  height: 42px;
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(255,255,255,.08);
  color: var(--cream);
  padding: 0 12px;
  outline: none;
}

.search-box input::placeholder {
  color: rgba(255,255,255,.45);
}

.upload-card {
  display: grid;
  gap: 12px;
  padding: 14px;
  background: rgba(223,185,96,.12);
  border: 1px solid rgba(223,185,96,.28);
}

.upload-card strong {
  display: block;
  font-size: 20px;
}

.upload-btn {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 40px;
  background: var(--gold);
  color: #231f1b;
  font-weight: 700;
  cursor: pointer;
}

.upload-btn input {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
}

.filter-group {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.style-picker {
  display: grid;
  gap: 8px;
  color: rgba(255,255,255,.72);
  font-size: 14px;
}

.style-picker select {
  height: 40px;
  border: 1px solid rgba(255,255,255,.16);
  background: rgba(255,255,255,.08);
  color: var(--cream);
  padding: 0 10px;
  outline: none;
}

.style-picker option {
  background: #241f1b;
  color: var(--cream);
}

.style-hint {
  color: rgba(255,255,255,.58);
  font-size: 12px;
  line-height: 1.45;
}

.filter-chip {
  min-height: 34px;
  border: 1px solid rgba(255,255,255,.15);
  background: transparent;
  color: rgba(255,255,255,.74);
  cursor: pointer;
}

.filter-chip.active {
  background: var(--oxide);
  color: var(--cream);
  border-color: var(--oxide);
}

.section-label {
  padding-top: 8px;
  border-top: 1px solid rgba(255,255,255,.12);
  color: rgba(255,255,255,.55);
  font-size: 13px;
}

.art-list {
  display: grid;
  gap: 12px;
  overflow: auto;
  padding-right: 3px;
}

.art-item {
  display: grid;
  grid-template-columns: 76px 1fr;
  gap: 12px;
  width: 100%;
  border: 1px solid rgba(255,255,255,.12);
  background: rgba(255,255,255,.05);
  color: inherit;
  padding: 9px;
  text-align: left;
  cursor: pointer;
}

.art-item.active {
  border-color: var(--gold);
  background: rgba(223,185,96,.14);
}

.art-item img {
  width: 76px;
  height: 66px;
  object-fit: cover;
  display: block;
}

.art-item strong {
  display: block;
  margin-bottom: 5px;
  font-size: 18px;
}

.art-item span {
  display: block;
  color: rgba(255,255,255,.62);
  font-size: 13px;
  line-height: 1.35;
}

.library-count {
  color: rgba(255,255,255,.48);
  font-size: 12px;
  line-height: 1.3;
}

.workspace {
  position: relative;
  overflow: hidden;
  background:
    linear-gradient(90deg, transparent 0, transparent calc(100% - 82px), rgba(230,218,202,.9) calc(100% - 82px)),
    var(--paper);
}

.workspace::after {
  content: "O";
  position: absolute;
  right: 34px;
  top: 56px;
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  background: var(--oxide);
  color: var(--cream);
  font-size: 26px;
  font-weight: 700;
}

.learning-nav {
  position: sticky;
  top: 0;
  z-index: 30;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  margin-right: 82px;
  background: var(--line);
  border-bottom: 1px solid var(--line);
}

.learning-tab {
  display: grid;
  grid-template-columns: auto 1fr;
  column-gap: 10px;
  align-items: center;
  min-height: 72px;
  padding: 12px 18px;
  border: 0;
  background: rgba(255,248,234,.94);
  color: var(--ink);
  text-align: left;
  cursor: pointer;
}

.learning-tab > span {
  grid-row: 1 / 3;
  color: var(--oxide);
  font: 800 12px/1 Arial, sans-serif;
  letter-spacing: .08em;
  writing-mode: vertical-rl;
  transform: rotate(180deg);
}

.learning-tab strong {
  font-size: 19px;
}

.learning-tab small {
  color: var(--muted);
  font-size: 12px;
}

.learning-tab.active {
  background: var(--night);
  color: var(--cream);
}

.learning-tab.active small {
  color: rgba(255,255,255,.62);
}

.learning-view[hidden] {
  display: none !important;
}

.mode-page {
  min-height: calc(100vh - 73px);
  padding: 44px 128px 54px 48px;
}

.mode-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 30px;
  margin-bottom: 28px;
}

.mode-header h2 {
  margin-bottom: 12px;
}

.mode-header > div > p:last-child {
  max-width: 760px;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.55;
}

.mode-step-badge {
  position: relative;
  display: block;
  min-width: 248px;
  padding: 12px 14px 14px;
  overflow: hidden;
  border: 3px solid var(--pop-charcoal);
  border-radius: 22px;
  background:
    radial-gradient(circle, rgba(47,115,62,.11) 1px, transparent 1.3px),
    linear-gradient(135deg, rgba(191,227,234,.42), transparent 46%),
    rgba(255,253,248,.95);
  background-size: 13px 13px, auto, auto;
  box-shadow:
    7px 7px 0 var(--pop-yellow),
    12px 13px 0 rgba(100,200,223,.28);
  transform: rotate(.35deg);
  cursor: pointer;
}

.step-selector-kicker {
  display: block;
  margin: 0 0 10px 2px;
  color: var(--pop-deep-green);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: .11em;
  text-transform: uppercase;
}

.step-selector-display {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 34px;
  align-items: center;
  gap: 11px;
}

.step-selector-copy {
  display: grid;
  min-width: 0;
  gap: 2px;
}

.step-selector-copy small {
  color: #719064;
  font-family: Arial, sans-serif;
  font-size: 9px;
  font-weight: 900;
  letter-spacing: .2em;
}

.step-selector-copy strong {
  overflow: hidden;
  color: var(--pop-charcoal);
  font-size: 21px;
  line-height: 1.18;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.step-selector-arrow {
  display: grid;
  place-items: center;
  width: 31px;
  height: 31px;
  border: 2px solid var(--pop-charcoal);
  border-radius: 50%;
  background: var(--pop-blue);
  color: var(--pop-deep-green);
  font-family: Arial, sans-serif;
  font-size: 21px;
  font-style: normal;
  line-height: 1;
  box-shadow: 3px 3px 0 var(--pop-yellow);
  transition: transform .18s ease;
}

.mode-step-badge select {
  position: absolute;
  z-index: 3;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
  opacity: 0;
  cursor: pointer;
}

.mode-step-badge:hover .step-selector-arrow,
.mode-step-badge:focus-within .step-selector-arrow {
  transform: translateY(2px) rotate(3deg);
}

.mode-step-badge:focus-within {
  border-color: var(--pop-charcoal);
  box-shadow:
    7px 7px 0 var(--pop-yellow),
    12px 13px 0 rgba(100,200,223,.5),
    0 0 0 4px rgba(99,173,79,.18);
}

.trace-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 24px;
}

.trace-studio,
.trace-guide,
.analysis-compare,
.analysis-card,
.growth-hero-card,
.growth-section {
  border: 1px solid var(--line);
  background: rgba(255,248,234,.74);
}

.trace-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 24px;
  padding: 14px;
  border-bottom: 1px solid var(--line);
}

.trace-toolbar label {
  display: flex;
  align-items: center;
  gap: 9px;
  color: var(--muted);
  font-size: 14px;
}

.trace-toolbar input[type="range"] {
  width: 118px;
  accent-color: var(--oxide);
}

.color-control input {
  width: 34px;
  height: 28px;
  padding: 0;
  border: 1px solid var(--line);
  background: transparent;
}

.stroke-coach,
.color-mixer {
  margin: 18px 18px 0;
  padding: 18px;
  border: 2px solid var(--pop-charcoal);
  border-radius: 18px;
  background: rgba(255,253,248,.9);
}

.stroke-coach {
  box-shadow: 6px 6px 0 rgba(247,216,63,.65);
}

.stroke-coach-head,
.mixer-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
}

.stroke-coach h3,
.mixer-head h3 {
  margin: 3px 0 0;
  font-size: 21px;
}

.stroke-count {
  flex: 0 0 auto;
  padding: 7px 11px;
  border: 2px solid var(--pop-charcoal);
  border-radius: 999px;
  background: var(--pop-yellow);
  font-variant-numeric: tabular-nums;
}

.stroke-instruction {
  min-height: 48px;
  margin: 14px 0 10px;
  color: var(--ink);
  font-size: 17px;
  line-height: 1.55;
}

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

.stroke-meta span {
  padding: 5px 9px;
  border-radius: 999px;
  background: rgba(191,227,234,.46);
  color: #4c533f;
  font-size: 13px;
}

.stroke-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: 14px;
}

.stroke-controls button,
.mixer-actions button {
  min-height: 38px;
  padding: 0 13px;
  border: 2px solid var(--pop-charcoal);
  border-radius: 999px;
  background: white;
  color: var(--pop-charcoal);
  cursor: pointer;
}

.stroke-controls button:disabled {
  opacity: .4;
  cursor: not-allowed;
}

.stroke-controls label {
  margin-left: auto;
  color: var(--muted);
  font-size: 13px;
}

.stroke-progress {
  height: 8px;
  margin-top: 14px;
  overflow: hidden;
  border: 1px solid rgba(48,50,50,.42);
  border-radius: 999px;
  background: rgba(48,50,50,.08);
}

.stroke-progress span {
  display: block;
  width: 0;
  height: 100%;
  background: var(--pop-green);
  transition: width .25s ease;
}

.segmented-control {
  display: flex;
}

.segmented-control button,
.trace-actions button {
  min-height: 38px;
  padding: 0 14px;
  border: 1px solid var(--line);
  background: var(--cream);
  color: var(--ink);
  cursor: pointer;
}

.segmented-control button + button {
  border-left: 0;
}

.segmented-control button.active,
.trace-actions button.active {
  background: var(--teal);
  color: white;
}

.trace-board {
  position: relative;
  aspect-ratio: 900 / 620;
  margin: 18px;
  overflow: hidden;
  border: 1px solid var(--line);
  background:
    linear-gradient(rgba(71,66,59,.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(71,66,59,.06) 1px, transparent 1px),
    #fffdf7;
  background-size: 24px 24px;
  touch-action: none;
}

.trace-board img,
.trace-board canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.trace-board img {
  object-fit: contain;
  pointer-events: none;
  opacity: .42;
}

.trace-board #traceGuideCanvas {
  z-index: 2;
  pointer-events: none;
}

.trace-board #traceCanvas {
  z-index: 3;
  cursor: crosshair;
}

.trace-empty-hint {
  position: absolute;
  z-index: 4;
  left: 50%;
  bottom: 18px;
  padding: 8px 12px;
  background: rgba(32,38,43,.78);
  color: white;
  font-size: 13px;
  transform: translateX(-50%);
  pointer-events: none;
}

.color-mixer {
  box-shadow: 6px 6px 0 rgba(100,200,223,.45);
}

.mixer-swatches {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 12px;
  color: var(--muted);
}

.mixer-swatches span {
  display: flex;
  align-items: center;
  gap: 6px;
}

.mixer-swatches i {
  display: inline-block;
  width: 30px;
  height: 30px;
  border: 2px solid var(--pop-charcoal);
  border-radius: 50%;
  background: #eee;
}

.mixer-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
  margin-top: 16px;
}

.mixer-recipe {
  margin: 0 0 6px;
  color: var(--ink);
  font-weight: 700;
  line-height: 1.5;
}

.mixer-method {
  margin: 0 0 14px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
}

.mixer-pigments {
  display: grid;
  gap: 9px;
}

.pigment-row {
  display: grid;
  grid-template-columns: 112px minmax(90px, 1fr) 34px;
  align-items: center;
  gap: 10px;
}

.pigment-label {
  display: flex;
  align-items: center;
  gap: 7px;
  color: #4c533f;
  font-size: 13px;
}

.pigment-label i {
  width: 17px;
  height: 17px;
  border: 1px solid rgba(48,50,50,.7);
  border-radius: 50%;
}

.pigment-row input {
  width: 100%;
  accent-color: var(--pop-green);
}

.pigment-row output {
  font-variant-numeric: tabular-nums;
  text-align: right;
}

.mixer-result {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  text-align: left;
}

.mixer-well {
  width: 100%;
  height: 78px;
  border: 3px solid var(--pop-charcoal);
  border-radius: 48% 52% 44% 56%;
  background: #eee;
  box-shadow:
    inset 0 0 0 9px rgba(255,255,255,.25),
    5px 5px 0 rgba(247,216,63,.55);
}

.mixer-result strong {
  margin-top: 12px;
  font-size: 18px;
}

.mixer-result small {
  margin-top: 7px;
  color: var(--muted);
  line-height: 1.45;
}

.mixer-actions {
  display: grid;
  gap: 7px;
  width: 100%;
  margin-top: 13px;
}

.mixer-actions #mixerUse {
  background: var(--pop-green);
  color: white;
}

.trace-actions {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  padding: 0 18px 18px;
}

.primary-action,
.complete-btn {
  min-height: 44px;
  padding: 0 18px;
  border: 0;
  background: var(--oxide);
  color: white;
  font-weight: 700;
  cursor: pointer;
}

.complete-btn {
  width: 100%;
  background: var(--green);
}

.trace-guide {
  align-self: start;
  padding: 22px;
}

.trace-guide ol {
  padding-left: 23px;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.65;
}

.trace-stop-card {
  margin-top: 22px;
  padding: 16px;
  border-left: 4px solid var(--green);
  background: #eef3e8;
}

.trace-stop-card p {
  margin: 7px 0 0;
  color: var(--muted);
  line-height: 1.5;
}

.understand-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(280px, .65fr);
  gap: 24px;
}

.analysis-compare {
  padding: 18px;
}

.analysis-labels {
  display: flex;
  justify-content: space-between;
  margin-bottom: 10px;
  color: var(--muted);
}

.analysis-image-wrap {
  position: relative;
  aspect-ratio: 900 / 620;
  overflow: hidden;
  background: #e8dfd2;
}

.analysis-image-wrap img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.analysis-stage {
  clip-path: inset(0 50% 0 0);
}

.analysis-divider {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 2px;
  background: white;
  box-shadow: 0 0 0 1px rgba(32,38,43,.48);
  transform: translateX(-1px);
}

.analysis-compare > input {
  width: 100%;
  margin-top: 14px;
  accent-color: var(--oxide);
}

.analysis-cards {
  display: grid;
  gap: 12px;
}

.analysis-card {
  padding: 18px;
}

.analysis-card > span {
  color: var(--oxide);
  font: 700 11px/1 Arial, sans-serif;
}

.analysis-card h3 {
  margin-top: 10px;
  font-size: 22px;
}

.analysis-card p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.55;
}

.growth-dashboard {
  display: grid;
  gap: 18px;
}

.growth-hero-card {
  display: grid;
  grid-template-columns: 160px 1fr;
  align-items: center;
  gap: 28px;
  padding: 26px;
}

.growth-ring {
  --growth: 0deg;
  position: relative;
  width: 138px;
  height: 138px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: conic-gradient(var(--teal) var(--growth), var(--paper-2) 0);
}

.growth-ring::after {
  content: "";
  position: absolute;
  inset: 12px;
  border-radius: 50%;
  background: var(--cream);
}

.growth-ring strong,
.growth-ring span {
  position: relative;
  z-index: 1;
  display: block;
  text-align: center;
}

.growth-ring strong {
  font-size: 28px;
}

.growth-ring span {
  color: var(--muted);
  font-size: 12px;
}

.growth-progress-track {
  height: 10px;
  overflow: hidden;
  background: var(--paper-2);
}

.growth-progress-track span {
  display: block;
  width: 0;
  height: 100%;
  background: var(--teal);
  transition: width .25s ease;
}

.growth-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.growth-stats article {
  padding: 20px;
  border: 1px solid var(--line);
  background: rgba(255,248,234,.74);
}

.growth-stats strong,
.growth-stats span {
  display: block;
}

.growth-stats strong {
  font-size: 36px;
}

.growth-stats span {
  color: var(--muted);
}

.growth-section {
  padding: 22px;
}

.section-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 20px;
}

.section-heading small {
  color: var(--muted);
}

.skill-badges {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin-top: 14px;
}

.skill-badge {
  min-height: 110px;
  padding: 15px;
  border: 1px solid var(--line);
  background: var(--paper);
  opacity: .5;
}

.skill-badge.earned {
  border-color: var(--gold);
  background: rgba(223,185,96,.16);
  opacity: 1;
}

.skill-badge strong,
.skill-badge span {
  display: block;
}

.skill-badge span {
  margin-top: 7px;
  color: var(--muted);
  font-size: 13px;
}

.recent-progress {
  display: grid;
  gap: 8px;
  margin-top: 14px;
}

.recent-item {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  padding: 12px 0;
  border-top: 1px solid var(--line);
}

.recent-item span {
  color: var(--muted);
  font-size: 13px;
}

.empty-progress {
  padding: 22px;
  color: var(--muted);
  text-align: center;
}

.hero-band {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 28px;
  padding: 42px 128px 24px 48px;
}

.meta-line {
  max-width: 760px;
  color: var(--muted);
  font-size: 18px;
}

.primary-btn,
.secondary-btn {
  border: 0;
  cursor: pointer;
  white-space: nowrap;
  min-height: 44px;
  padding: 0 20px;
  font-weight: 700;
}

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

.secondary-btn {
  width: 100%;
  background: var(--oxide);
  color: var(--cream);
}

.stage-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 292px;
  gap: 24px;
  padding: 0 128px 22px 48px;
}

.viewer-zone {
  min-width: 0;
}

.viewer-toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  margin-bottom: 12px;
}

.tool-buttons {
  display: flex;
  gap: 8px;
}

.icon-btn {
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  background: var(--cream);
  color: var(--ink);
  cursor: pointer;
  font-size: 22px;
  line-height: 1;
}

.icon-btn.active {
  background: var(--teal);
  color: white;
  border-color: var(--teal);
}

.art-viewer {
  position: relative;
  height: min(46vh, 420px);
  min-height: 300px;
  overflow: hidden;
  background: #e8dfd2;
  border: 1px solid var(--line);
}

.art-viewer.loading::before {
  content: "正在生成图例步骤...";
  position: absolute;
  inset: 0;
  z-index: 5;
  display: grid;
  place-items: center;
  background: rgba(245,238,226,.78);
  color: var(--ink);
  font-size: 24px;
  font-weight: 700;
}

.art-viewer img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  transition: opacity .25s ease, clip-path .25s ease;
}

.stage-layer {
  filter: var(--stage-filter, none);
}

.visual-overlay {
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: var(--overlay-opacity, .18);
  background:
    linear-gradient(90deg, rgba(184,92,56,.26) 0 18%, transparent 18% 22%, rgba(40,106,115,.18) 22% 48%, transparent 48% 54%, rgba(223,185,96,.2) 54% 100%);
  mix-blend-mode: multiply;
  transition: opacity .2s ease, background .2s ease;
}

.final-layer {
  opacity: 0;
}

.compare .final-layer {
  opacity: 1;
}

.compare .stage-layer {
  clip-path: inset(0 48% 0 0);
}

.compare-slider {
  position: absolute;
  left: 40px;
  right: 40px;
  bottom: 20px;
  width: calc(100% - 80px);
  display: none;
  accent-color: var(--oxide);
}

.compare .compare-slider {
  display: block;
}

.step-rail {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 10px;
  margin-top: 12px;
}

.step-btn {
  border: 1px solid var(--line);
  background: rgba(255,248,234,.72);
  color: var(--ink);
  min-height: 80px;
  padding: 9px;
  text-align: left;
  cursor: pointer;
}

.step-btn img {
  width: 100%;
  height: 54px;
  object-fit: cover;
  display: block;
  margin-bottom: 8px;
  filter: var(--thumb-filter, none);
}

.step-btn .diff-note {
  display: block;
  color: inherit;
  opacity: .68;
  font-size: 13px;
  line-height: 1.25;
  margin-top: 4px;
}

.step-btn.active {
  background: var(--teal);
  color: white;
  border-color: var(--teal);
}

.step-btn span {
  display: block;
  font-family: Arial, sans-serif;
  font-size: 11px;
  font-weight: 700;
  margin-bottom: 8px;
}

.step-btn strong {
  display: block;
  font-size: 20px;
  line-height: 1.1;
}

.guide-panel {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.guide-card {
  background: rgba(255,248,234,.72);
  border: 1px solid var(--line);
  padding: 18px;
}

.guide-card p {
  color: var(--muted);
  font-size: 17px;
  line-height: 1.5;
}

.guide-card ul {
  margin: 0;
  padding-left: 20px;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.55;
}

.beginner-check-card {
  border-left: 4px solid var(--green);
  background: rgba(241,246,235,.82);
}

.beginner-check-card h3 {
  font-size: 22px;
}

.avoid-line {
  margin-bottom: 0;
  padding-top: 10px;
  border-top: 1px dashed var(--line);
}

.avoid-line strong {
  color: var(--oxide);
}

.micro-panel {
  margin: 4px 128px 34px 48px;
  padding: 20px;
  border-top: 2px solid var(--line);
  background: rgba(239,229,215,.84);
  transform: translateY(20px);
  opacity: 0;
  pointer-events: none;
  transition: transform .2s ease, opacity .2s ease;
}

.micro-panel.open {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.micro-header {
  display: flex;
  justify-content: space-between;
  align-items: start;
  gap: 20px;
}

.micro-steps {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
  margin-top: 14px;
}

.micro-step {
  border: 1px solid var(--line);
  background: var(--paper);
  padding: 10px;
  min-height: 210px;
}

.micro-visual {
  position: relative;
  height: 116px;
  margin-bottom: 12px;
  border: 1px solid var(--line);
  background:
    linear-gradient(90deg, rgba(255,255,255,.16), rgba(255,255,255,0)),
    #efe3cf;
  overflow: hidden;
}

.micro-visual img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.micro-base-img {
  opacity: var(--micro-base-opacity, 1);
  filter: saturate(.62) contrast(.92) brightness(1.08);
}

.micro-progress-img {
  clip-path: inset(0 calc(100% - var(--micro-progress)) 0 0);
  filter: saturate(.95) contrast(.98);
}

.micro-progress-line {
  position: absolute;
  top: 0;
  bottom: 0;
  left: var(--micro-progress);
  width: 2px;
  background: rgba(32,38,43,.62);
  box-shadow: 0 0 0 1px rgba(255,248,234,.72);
  transform: translateX(-1px);
}

.micro-step:last-child .micro-progress-line {
  display: none;
}

.micro-step strong {
  display: block;
  margin-bottom: 8px;
  font-size: 18px;
  line-height: 1.25;
}

.micro-step p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.45;
}

img {
  cursor: zoom-in;
}

.zoom-modal {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: none;
  place-items: center;
  padding: 34px;
  background: rgba(18, 16, 14, .88);
}

.zoom-modal.open {
  display: grid;
}

.zoom-frame {
  position: relative;
  display: grid;
  justify-items: center;
  gap: 12px;
  max-width: 96vw;
  max-height: 94vh;
}

.zoom-frame img {
  max-width: 92vw;
  max-height: 84vh;
  object-fit: contain;
  background: #f5efe4;
  border: 1px solid rgba(255,248,234,.32);
  box-shadow: 0 24px 70px rgba(0,0,0,.42);
  cursor: zoom-in;
  transition: transform .18s ease;
}

.zoom-modal.zoomed .zoom-frame {
  overflow: auto;
  width: 96vw;
  height: 92vh;
  align-items: start;
}

.zoom-modal.zoomed .zoom-frame img {
  max-width: none;
  max-height: none;
  width: min(1800px, 180vw);
  cursor: zoom-out;
}

.zoom-frame p {
  margin: 0;
  color: var(--cream);
  font-size: 16px;
}

.zoom-close {
  position: fixed;
  top: 18px;
  right: 22px;
  z-index: 1001;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(255,248,234,.32);
  background: rgba(245,238,226,.12);
  color: var(--cream);
  cursor: pointer;
  font-size: 30px;
  line-height: 1;
}

@media (max-width: 980px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .library-panel {
    min-height: auto;
    max-height: none;
    overflow: visible;
  }

  .library-panel .art-list {
    max-height: 210px;
    overflow: auto;
  }

  .stage-grid,
  .hero-band,
  .micro-panel,
  .mode-page {
    margin-right: 0;
    padding-right: 28px;
  }

  .stage-grid,
  .trace-layout,
  .understand-grid {
    grid-template-columns: 1fr;
  }

  .step-rail,
  .micro-steps,
  .skill-badges,
  .growth-stats {
    grid-template-columns: 1fr 1fr;
  }

  .learning-nav {
    position: static;
    margin-right: 0;
    grid-template-columns: 1fr 1fr;
  }

  .mode-page {
    padding-left: 28px;
  }

  .growth-hero-card {
    grid-template-columns: 1fr;
  }

  .stroke-coach-head,
  .mixer-head {
    display: grid;
  }

  .stroke-controls label {
    width: 100%;
    margin-left: 0;
  }

  .mixer-body {
    grid-template-columns: 1fr;
  }

  .mixer-result {
    align-items: stretch;
    text-align: left;
  }

  .mixer-well {
    width: 100%;
    height: 76px;
  }

  .zoom-modal {
    padding: 18px;
  }

  .zoom-frame img {
    max-width: 94vw;
    max-height: 82vh;
  }
}

@media (max-width: 560px) {
  .stroke-coach,
  .color-mixer {
    margin: 14px 12px 0;
    padding: 15px;
  }

  .stroke-controls button {
    flex: 1 1 30%;
    padding: 0 8px;
  }

  .pigment-row {
    grid-template-columns: 104px minmax(70px, 1fr) 28px;
    gap: 7px;
  }
}

/* Obra botanical watercolor identity */
:root {
  --paper: #f2ece3;
  --paper-2: #e9e4da;
  --ink: #333333;
  --muted: #6f746b;
  --oxide: #6e965c;
  --teal: #7baf5a;
  --green: #5f8951;
  --gold: #f2d56b;
  --line: rgba(91, 112, 79, .18);
  --night: #507747;
  --cream: #fffdf8;
  --mist-blue: #bfdde6;
  --leaf: #7baf5a;
  --sun: #f2d56b;
}

body {
  background:
    radial-gradient(circle at 12% 8%, rgba(255,255,255,.86), transparent 24%),
    radial-gradient(circle at 88% 13%, rgba(191,221,230,.16), transparent 22%),
    repeating-linear-gradient(7deg, rgba(91,80,61,.018) 0 1px, transparent 1px 5px),
    #f2ece3;
  color: var(--ink);
  font-family: "Source Han Serif SC", "思源宋体", "Songti SC", "STSong", serif;
}

button,
input,
select {
  border-radius: 12px;
}

.library-panel {
  position: relative;
  color: var(--ink);
  background:
    radial-gradient(circle at 18% 5%, rgba(191,221,230,.46), transparent 24%),
    radial-gradient(circle at 86% 18%, rgba(242,213,107,.2), transparent 19%),
    linear-gradient(180deg, rgba(255,253,248,.97), rgba(242,236,227,.97));
  border-right: 1px solid rgba(91,112,79,.18);
  box-shadow: 12px 0 34px rgba(66,79,56,.07);
}

.library-panel::after {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 190px;
  pointer-events: none;
  opacity: .22;
  background:
    radial-gradient(ellipse at 12% 100%, #7baf5a 0 8%, transparent 9%),
    radial-gradient(ellipse at 34% 100%, #bfdde6 0 13%, transparent 14%),
    radial-gradient(ellipse at 65% 100%, #7baf5a 0 10%, transparent 11%),
    radial-gradient(ellipse at 88% 100%, #f2d56b 0 7%, transparent 8%);
  filter: blur(14px);
}

.brand-row {
  position: relative;
  z-index: 1;
}

.seal {
  position: relative;
  overflow: hidden;
  width: 58px;
  height: 58px;
  border-radius: 19px;
  background:
    radial-gradient(circle at 62% 34%, var(--sun) 0 7%, transparent 8%),
    radial-gradient(ellipse at 48% 55%, transparent 0 30%, rgba(78,132,68,.92) 32% 38%, transparent 40%),
    linear-gradient(145deg, rgba(255,255,255,.95), rgba(242,236,227,.96));
  color: var(--green);
  box-shadow:
    0 9px 20px rgba(66,79,56,.15),
    inset 0 0 0 1px rgba(255,255,255,.86);
  font-family: Georgia, serif;
  font-size: 31px;
}

.brand-row h1 {
  color: #527848;
  font-size: 31px;
  letter-spacing: .08em;
}

.eyebrow {
  color: #648a56;
  font-family: "Source Han Sans SC", "思源黑体", Arial, sans-serif;
  letter-spacing: .1em;
}

.search-box,
.style-picker {
  color: #687062;
}

.search-box input,
.style-picker select {
  border-color: rgba(95,137,81,.2);
  background: rgba(255,255,255,.64);
  color: var(--ink);
  box-shadow: inset 0 1px 1px rgba(79,75,66,.04);
}

.search-box input::placeholder {
  color: #9a9b93;
}

.style-picker option {
  background: #fffdf8;
  color: var(--ink);
}

.style-hint,
.section-label,
.library-count {
  color: #7a8174;
}

.section-label {
  border-top-color: rgba(95,137,81,.16);
}

.upload-card {
  border-color: rgba(123,175,90,.28);
  border-radius: 18px;
  background:
    linear-gradient(135deg, rgba(191,221,230,.27), rgba(255,255,255,.58) 42%, rgba(242,213,107,.18));
  box-shadow: 0 10px 24px rgba(66,79,56,.06);
}

.upload-btn {
  border-radius: 999px;
  background: var(--sun);
  color: #4c533f;
  box-shadow: 0 5px 12px rgba(202,171,61,.14);
}

.filter-chip {
  border-color: rgba(95,137,81,.19);
  border-radius: 999px;
  background: rgba(255,255,255,.46);
  color: #65705f;
}

.filter-chip.active {
  border-color: #7baf5a;
  background: #7baf5a;
  color: white;
  box-shadow: 0 5px 12px rgba(91,137,76,.16);
}

.art-item {
  border-color: rgba(95,137,81,.14);
  border-radius: 16px;
  background: rgba(255,255,255,.5);
  box-shadow: 0 5px 14px rgba(66,79,56,.035);
}

.art-item.active {
  border-color: rgba(123,175,90,.72);
  background: rgba(123,175,90,.12);
  box-shadow: 0 8px 20px rgba(78,115,67,.11);
}

.art-item img {
  border-radius: 11px;
}

.art-item strong {
  color: #40513d;
}

.art-item span,
.art-item span span {
  color: #73796e;
}

.workspace {
  background:
    radial-gradient(circle at 84% 0, rgba(191,221,230,.18), transparent 22%),
    radial-gradient(circle at 68% 95%, rgba(123,175,90,.1), transparent 28%),
    repeating-linear-gradient(-4deg, rgba(76,71,61,.014) 0 1px, transparent 1px 6px),
    #f7f3ec;
}

.workspace::after {
  border-radius: 50%;
  background: transparent;
  color: #628a55;
  border: 2px solid rgba(95,137,81,.62);
  font-family: Georgia, serif;
  box-shadow: 0 8px 18px rgba(66,79,56,.08);
}

.learning-nav {
  gap: 10px;
  padding: 12px 18px;
  background: rgba(247,243,236,.9);
  border-bottom-color: rgba(95,137,81,.15);
  backdrop-filter: blur(12px);
}

.learning-tab {
  min-height: 68px;
  border: 1px solid rgba(95,137,81,.15);
  border-radius: 18px;
  background: rgba(255,253,248,.76);
  box-shadow: 0 5px 14px rgba(66,79,56,.045);
}

.learning-tab > span {
  color: #6d955e;
}

.learning-tab strong {
  color: #4d6648;
}

.learning-tab.active {
  border-color: rgba(123,175,90,.48);
  background:
    linear-gradient(135deg, rgba(123,175,90,.95), rgba(102,148,88,.95));
  color: white;
  box-shadow: 0 9px 22px rgba(72,116,61,.18);
}

.learning-tab.active strong,
.learning-tab.active > span {
  color: white;
}

h2,
h3 {
  color: #394b38;
}

.primary-btn,
.primary-action {
  border-radius: 999px;
  background: #5f8951;
  box-shadow: 0 7px 16px rgba(75,117,65,.16);
}

.secondary-btn {
  border-radius: 999px;
  background: #7baf5a;
}

.complete-btn {
  border-radius: 999px;
  background: #f2d56b;
  color: #4e543f;
}

.icon-btn,
.step-btn,
.guide-card,
.micro-step,
.trace-studio,
.trace-guide,
.analysis-compare,
.analysis-card,
.growth-hero-card,
.growth-section,
.growth-stats article,
.mode-step-badge {
  border-color: rgba(95,137,81,.17);
  border-radius: 18px;
  background: rgba(255,253,248,.72);
  box-shadow: 0 8px 24px rgba(66,79,56,.055);
}

.icon-btn.active,
.step-btn.active {
  border-color: #7baf5a;
  background: #7baf5a;
  color: white;
}

.art-viewer,
.micro-visual,
.trace-board,
.analysis-image-wrap {
  border-color: rgba(95,137,81,.16);
  border-radius: 20px;
  background:
    linear-gradient(rgba(95,137,81,.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(95,137,81,.035) 1px, transparent 1px),
    #fdfbf6;
  background-size: 24px 24px;
  box-shadow:
    0 18px 36px rgba(66,79,56,.08),
    inset 0 0 0 8px rgba(255,255,255,.42);
}

.step-btn img {
  border-radius: 11px;
}

.guide-card p,
.guide-card ul,
.trace-guide ol,
.analysis-card p {
  color: #70776b;
}

.beginner-check-card,
.trace-stop-card {
  border-left-color: #7baf5a;
  background: rgba(123,175,90,.1);
}

.avoid-line strong {
  color: #668e57;
}

.micro-panel {
  border-top-color: rgba(95,137,81,.18);
  border-radius: 24px;
  background:
    radial-gradient(circle at 92% 15%, rgba(191,221,230,.22), transparent 24%),
    rgba(242,236,227,.82);
}

.trace-toolbar {
  border-bottom-color: rgba(95,137,81,.15);
}

.segmented-control button,
.trace-actions button {
  border-color: rgba(95,137,81,.2);
  background: rgba(255,253,248,.86);
}

.segmented-control button.active,
.trace-actions button.active {
  background: #7baf5a;
}

.trace-empty-hint {
  border-radius: 999px;
  background: rgba(82,120,72,.86);
}

.analysis-divider {
  background: #f2d56b;
  box-shadow: 0 0 0 1px rgba(95,137,81,.3);
}

.growth-ring {
  background: conic-gradient(#7baf5a var(--growth), rgba(191,221,230,.32) 0);
}

.growth-progress-track {
  border-radius: 999px;
  background: rgba(191,221,230,.35);
}

.growth-progress-track span {
  border-radius: 999px;
  background: linear-gradient(90deg, #7baf5a, #a5c96d);
}

.skill-badge {
  border-color: rgba(95,137,81,.15);
  border-radius: 16px;
  background: rgba(255,255,255,.48);
}

.skill-badge.earned {
  border-color: rgba(123,175,90,.48);
  background:
    radial-gradient(circle at 88% 16%, rgba(242,213,107,.3), transparent 24%),
    rgba(123,175,90,.12);
}

.recent-item {
  border-top-color: rgba(95,137,81,.14);
}

input[type="range"] {
  accent-color: #7baf5a;
}

/* Botanical pop: bold blocks, handmade outlines and halftone rhythm */
:root {
  --pop-green: #63ad4f;
  --pop-deep-green: #2f733e;
  --pop-yellow: #f7d83f;
  --pop-blue: #bfe3ea;
  --pop-cream: #f6efe5;
  --pop-charcoal: #303232;
}

body {
  background-color: var(--pop-cream);
  background-image:
    radial-gradient(circle, rgba(47,115,62,.09) 1.2px, transparent 1.5px),
    radial-gradient(circle at 18% 9%, rgba(191,227,234,.62), transparent 23%),
    radial-gradient(circle at 88% 24%, rgba(247,216,63,.17), transparent 17%);
  background-position: 0 0, 0 0, 0 0;
  background-size: 15px 15px, auto, auto;
}

.library-panel {
  border-right: 3px solid var(--pop-charcoal);
}

.brand-row h1 {
  color: var(--pop-deep-green);
  font-size: 36px;
  font-weight: 800;
  text-shadow: 2px 2px 0 rgba(247,216,63,.72);
}

.seal {
  border: 2px solid var(--pop-charcoal);
  box-shadow:
    6px 6px 0 var(--pop-yellow),
    0 12px 22px rgba(54,77,49,.12);
  transform: rotate(-2deg);
}

.seal img {
  display: block;
  width: 100%;
  height: 100%;
  border-radius: inherit;
  object-fit: cover;
}

.upload-card,
.art-item,
.guide-card,
.trace-studio,
.trace-guide,
.analysis-compare,
.analysis-card,
.growth-hero-card,
.growth-section,
.growth-stats article {
  border-width: 2px;
  border-color: rgba(48,50,50,.72);
}

.upload-card {
  box-shadow: 6px 6px 0 rgba(191,227,234,.72);
}

.upload-btn,
.complete-btn {
  border: 2px solid var(--pop-charcoal);
  box-shadow: 4px 4px 0 var(--pop-green);
}

.filter-chip {
  border-width: 2px;
  border-color: rgba(48,50,50,.68);
}

.filter-chip.active {
  border-color: var(--pop-charcoal);
  background: var(--pop-yellow);
  color: var(--pop-charcoal);
  box-shadow: 3px 3px 0 var(--pop-green);
}

.art-item.active {
  border-color: var(--pop-charcoal);
  background:
    radial-gradient(circle, rgba(47,115,62,.13) 1.2px, transparent 1.5px),
    rgba(247,216,63,.24);
  background-size: 12px 12px;
  box-shadow: 5px 5px 0 var(--pop-blue);
}

.learning-nav {
  gap: 12px;
  background:
    linear-gradient(90deg, rgba(191,227,234,.56), rgba(246,239,229,.84) 40%, rgba(247,216,63,.2));
}

.learning-tab {
  border: 2px solid var(--pop-charcoal);
  box-shadow: 4px 4px 0 rgba(48,50,50,.13);
  transition: transform .16s ease, box-shadow .16s ease;
}

.learning-tab:nth-child(2) {
  transform: rotate(.35deg);
}

.learning-tab:nth-child(3) {
  transform: rotate(-.35deg);
}

.learning-tab:hover {
  transform: translate(-1px, -2px);
  box-shadow: 6px 7px 0 rgba(48,50,50,.15);
}

.learning-tab.active {
  border-color: var(--pop-charcoal);
  background:
    radial-gradient(circle, rgba(255,255,255,.22) 1.2px, transparent 1.6px),
    var(--pop-green);
  background-size: 13px 13px;
  box-shadow: 6px 6px 0 var(--pop-yellow);
  transform: translate(-2px, -2px);
}

.learning-tab > span {
  font-weight: 900;
}

.mode-header h2,
.hero-band h2 {
  display: inline;
  background:
    linear-gradient(transparent 65%, rgba(247,216,63,.72) 65% 90%, transparent 90%);
  text-shadow: 1px 1px 0 white;
}

.primary-btn,
.primary-action,
.secondary-btn {
  border: 2px solid var(--pop-charcoal);
  color: var(--pop-charcoal);
  box-shadow: 5px 5px 0 var(--pop-yellow);
}

.primary-btn,
.primary-action {
  background: var(--pop-green);
  color: white;
  box-shadow: 5px 5px 0 var(--pop-blue);
}

.secondary-btn {
  background: var(--pop-blue);
}

.icon-btn,
.step-btn,
.mode-step-badge {
  border-width: 2px;
  border-color: rgba(48,50,50,.7);
}

.icon-btn.active,
.step-btn.active {
  border-color: var(--pop-charcoal);
  background: var(--pop-green);
  box-shadow: 4px 4px 0 var(--pop-yellow);
}

.step-btn:nth-child(3n + 2) {
  transform: rotate(.25deg);
}

.step-btn:nth-child(3n) {
  transform: rotate(-.25deg);
}

.art-viewer,
.trace-board,
.analysis-image-wrap {
  border: 3px solid var(--pop-charcoal);
  box-shadow:
    9px 9px 0 rgba(191,227,234,.75),
    0 20px 36px rgba(54,77,49,.08);
}

.beginner-check-card,
.trace-stop-card {
  position: relative;
  border-left: 8px solid var(--pop-green);
}

.beginner-check-card::after,
.trace-stop-card::after {
  content: "";
  position: absolute;
  top: 14px;
  right: 15px;
  width: 25px;
  height: 25px;
  border: 2px solid var(--pop-charcoal);
  border-radius: 50%;
  background:
    radial-gradient(circle at 50% 50%, var(--pop-yellow) 0 32%, transparent 34%),
    white;
  box-shadow: 3px 3px 0 var(--pop-blue);
}

.analysis-card:nth-child(1) {
  box-shadow: 6px 6px 0 rgba(191,227,234,.78);
}

.analysis-card:nth-child(2) {
  box-shadow: 6px 6px 0 rgba(247,216,63,.62);
}

.analysis-card:nth-child(3) {
  box-shadow: 6px 6px 0 rgba(99,173,79,.45);
}

.analysis-card > span {
  display: inline-block;
  padding: 5px 9px;
  border: 2px solid var(--pop-charcoal);
  border-radius: 999px;
  background: var(--pop-yellow);
  color: var(--pop-charcoal);
}

.trace-toolbar {
  background:
    radial-gradient(circle, rgba(47,115,62,.1) 1.1px, transparent 1.4px),
    rgba(191,227,234,.24);
  background-size: 14px 14px;
}

.segmented-control button,
.trace-actions button {
  border-width: 2px;
  border-color: var(--pop-charcoal);
}

.segmented-control button.active,
.trace-actions button.active {
  background: var(--pop-yellow);
  color: var(--pop-charcoal);
}

.growth-ring {
  border: 3px solid var(--pop-charcoal);
  box-shadow: 6px 6px 0 var(--pop-yellow);
}

.growth-stats article:nth-child(1) {
  background: rgba(191,227,234,.36);
}

.growth-stats article:nth-child(2) {
  background: rgba(247,216,63,.24);
}

.growth-stats article:nth-child(3) {
  background: rgba(99,173,79,.17);
}

.growth-stats article:nth-child(4) {
  background: rgba(255,255,255,.56);
}

.skill-badge.earned {
  border: 2px solid var(--pop-charcoal);
  box-shadow: 4px 4px 0 var(--pop-yellow);
}

@media (prefers-reduced-motion: reduce) {
  .learning-tab,
  .step-btn {
    transform: none !important;
    transition: none;
  }
}

/* Bright modern color planes inspired by sunlit pools and playful perspective */
:root {
  --pool-blue: #64c8df;
  --sky-blue: #a9dfea;
  --coral: #f28e72;
  --lilac: #aaa5d9;
}

.workspace {
  background:
    linear-gradient(118deg, transparent 0 73%, rgba(100,200,223,.12) 73% 81%, transparent 81%),
    radial-gradient(circle at 84% 0, rgba(100,200,223,.2), transparent 22%),
    radial-gradient(circle at 68% 95%, rgba(123,175,90,.1), transparent 28%),
    repeating-linear-gradient(-4deg, rgba(76,71,61,.014) 0 1px, transparent 1px 6px),
    #f7f3ec;
}

.learning-tab:nth-child(2) {
  background: rgba(100,200,223,.2);
}

.learning-tab:nth-child(3) {
  background: rgba(242,142,114,.13);
}

.learning-tab:nth-child(4) {
  background: rgba(170,165,217,.14);
}

.learning-tab:nth-child(2).active {
  background:
    linear-gradient(135deg, rgba(255,255,255,.16), transparent 45%),
    var(--pool-blue);
}

.learning-tab:nth-child(3).active {
  background:
    linear-gradient(135deg, rgba(255,255,255,.14), transparent 45%),
    var(--coral);
}

.learning-tab:nth-child(4).active {
  background:
    linear-gradient(135deg, rgba(255,255,255,.18), transparent 45%),
    var(--lilac);
}

.trace-board {
  background:
    linear-gradient(132deg, transparent 0 62%, rgba(100,200,223,.13) 62% 74%, transparent 74%),
    repeating-linear-gradient(0deg, rgba(48,50,50,.035) 0 1px, transparent 1px 26px),
    repeating-linear-gradient(90deg, rgba(48,50,50,.035) 0 1px, transparent 1px 26px),
    #fffdf7;
}

.analysis-image-wrap::after {
  content: "";
  position: absolute;
  right: 18px;
  bottom: 18px;
  width: 74px;
  height: 20px;
  border: 2px solid var(--pop-charcoal);
  background: var(--pool-blue);
  box-shadow: 5px 5px 0 var(--pop-yellow);
  transform: skewX(-18deg);
  pointer-events: none;
  opacity: .72;
}

.analysis-card:nth-child(1) {
  background: rgba(100,200,223,.13);
  box-shadow: 6px 6px 0 rgba(100,200,223,.74);
}

.analysis-card:nth-child(2) {
  background: rgba(247,216,63,.12);
}

.analysis-card:nth-child(3) {
  background: rgba(242,142,114,.1);
  box-shadow: 6px 6px 0 rgba(242,142,114,.5);
}

.growth-stats article:nth-child(2) {
  background: rgba(100,200,223,.25);
}

.growth-stats article:nth-child(3) {
  background: rgba(247,216,63,.24);
}

.growth-stats article:nth-child(4) {
  background: rgba(242,142,114,.16);
}

.skill-badge.earned {
  box-shadow: 4px 4px 0 var(--pool-blue);
}

.growth-section:nth-of-type(2) {
  background:
    linear-gradient(160deg, rgba(100,200,223,.12), transparent 48%),
    rgba(255,253,248,.72);
}

.growth-section:nth-of-type(3) {
  background:
    linear-gradient(20deg, rgba(247,216,63,.13), transparent 52%),
    rgba(255,253,248,.72);
}

/* TRACE stage selector: keep the native control, dress it like an Obra card. */
.mode-header .mode-step-badge {
  min-width: 248px;
  padding: 12px 14px 14px;
  border: 3px solid var(--pop-charcoal);
  border-radius: 22px;
  background:
    radial-gradient(circle, rgba(47,115,62,.11) 1px, transparent 1.3px),
    linear-gradient(135deg, rgba(191,227,234,.42), transparent 46%),
    rgba(255,253,248,.95);
  background-size: 13px 13px, auto, auto;
  box-shadow:
    7px 7px 0 var(--pop-yellow),
    12px 13px 0 rgba(100,200,223,.28);
}

#traceStepNumber,
.step-selector-number {
  display: none !important;
}

.workspace::after {
  content: none !important;
  display: none !important;
}

.learning-nav {
  margin-right: 0;
}

.trace-expanded-only {
  display: none;
}

body.trace-expanded-open {
  overflow: hidden;
}

.trace-board.trace-expanded {
  position: fixed;
  inset: 0;
  z-index: 1200;
  width: 100vw;
  height: 100dvh;
  aspect-ratio: auto;
  margin: 0;
  border: 0;
  border-radius: 0;
  background:
    radial-gradient(circle at 50% 50%, rgba(191,227,234,.16), transparent 36%),
    #f7f3ec;
  isolation: isolate;
}

.trace-board.trace-expanded img,
.trace-board.trace-expanded canvas {
  inset: auto;
  left: 50%;
  top: calc(50% - 42px);
  width: min(96vw, calc((100dvh - 178px) * 1.4516));
  height: min(calc(100dvh - 178px), calc(96vw / 1.4516));
  transform: translate(-50%, -50%);
}

.trace-board.trace-expanded img {
  border: 3px solid var(--pop-charcoal);
  border-radius: 26px;
  box-shadow:
    9px 10px 0 rgba(191,227,234,.8),
    0 22px 70px rgba(48,50,50,.2);
}

.trace-board.trace-expanded .trace-empty-hint {
  bottom: 136px;
}

.trace-board.trace-expanded .trace-expanded-only {
  display: flex;
}

.trace-expand-close {
  position: absolute;
  top: 14px;
  right: 16px;
  z-index: 11;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: 3px solid var(--pop-charcoal);
  border-radius: 50%;
  background: #fffdf8;
  color: var(--pop-charcoal);
  font-size: 28px;
  line-height: 1;
  box-shadow: 4px 5px 0 rgba(100,200,223,.4);
}

.trace-side-step {
  position: absolute;
  z-index: 10;
  top: 50%;
  align-items: center;
  justify-content: center;
  min-width: 74px;
  min-height: 54px;
  padding: 0 16px;
  border: 3px solid var(--pop-charcoal);
  border-radius: 999px;
  background: #fffdf8;
  color: var(--pop-charcoal);
  font-weight: 800;
  box-shadow: 5px 6px 0 rgba(247,216,63,.72);
  transform: translateY(-50%);
}

.trace-side-step:disabled {
  opacity: .42;
}

.trace-side-step-prev {
  left: max(12px, env(safe-area-inset-left));
}

.trace-side-step-next {
  right: max(12px, env(safe-area-inset-right));
}

.trace-expand-bottom {
  position: absolute;
  z-index: 10;
  left: 50%;
  bottom: max(14px, env(safe-area-inset-bottom));
  width: min(720px, calc(100vw - 24px));
  gap: 10px;
  transform: translateX(-50%);
}

.trace-board.trace-expanded .trace-expand-bottom {
  display: grid !important;
}

.trace-expand-play-row {
  display: flex;
  justify-content: center;
}

.trace-expand-play-row button,
.trace-expand-actions button {
  min-height: 48px;
  padding: 0 18px;
  border: 3px solid var(--pop-charcoal);
  border-radius: 999px;
  background: #fffdf8;
  color: var(--pop-charcoal);
  font-size: 17px;
  font-weight: 800;
  box-shadow: 5px 6px 0 rgba(191,227,234,.86);
}

.trace-expand-play-row button {
  min-width: 170px;
  background: var(--pop-yellow);
}

.trace-expand-actions {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, auto));
  justify-content: center;
  gap: 10px;
}

.trace-expand-actions .primary-action {
  min-width: 176px;
}

@media (max-width: 560px) {
  .mode-header {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    gap: 16px;
  }

  .mode-header .mode-step-badge {
    min-width: 0;
    width: 100%;
    padding: 10px 11px 12px;
    border-radius: 19px;
    box-shadow:
      5px 5px 0 var(--pop-yellow),
      9px 9px 0 rgba(100,200,223,.26);
  }

  .step-selector-kicker {
    margin-bottom: 8px;
    font-size: 9px;
    letter-spacing: .07em;
  }

  .step-selector-display {
    grid-template-columns: minmax(0, 1fr) 30px;
    gap: 10px;
  }

  .step-selector-copy strong {
    font-size: 19px;
  }

  .step-selector-arrow {
    width: 26px;
    height: 26px;
    font-size: 17px;
  }

  .trace-board.trace-expanded img,
  .trace-board.trace-expanded canvas {
    top: calc(50% - 54px);
    width: min(96vw, calc((100dvh - 208px) * 1.4516));
    height: min(calc(100dvh - 208px), calc(96vw / 1.4516));
  }

  .trace-side-step {
    min-width: 56px;
    min-height: 48px;
    padding: 0 10px;
    font-size: 14px;
  }

  .trace-expand-actions {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 7px;
  }

  .trace-expand-play-row button,
  .trace-expand-actions button {
    min-height: 46px;
    padding: 0 8px;
    font-size: 15px;
  }

  .trace-expand-actions .primary-action {
    min-width: 0;
  }
}