:root {
  --bg: #f5f1e8;
  --paper: rgba(255, 251, 244, 0.86);
  --paper-strong: rgba(255, 251, 244, 0.97);
  --ink: #1d2430;
  --muted: #55606f;
  --line: rgba(29, 36, 48, 0.12);
  --accent: #0d7a72;
  --accent-2: #d56c1d;
  --accent-soft: rgba(13, 122, 114, 0.1);
  --shadow: 0 22px 55px rgba(48, 43, 34, 0.12);
  --radius: 24px;
  --radius-sm: 16px;
  --title-font: "Noto Serif SC", "Source Han Serif SC", "STSong", serif;
  --body-font: "Avenir Next", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

* {
  box-sizing: border-box;
}

.skip-link {
  position: absolute;
  left: 12px;
  top: 12px;
  padding: 10px 16px;
  border-radius: 999px;
  background: var(--ink);
  color: #fffdf8;
  font-weight: 700;
  font-size: 0.9rem;
  z-index: 20;
  transform: translateY(-160%);
  transition: transform 160ms ease;
}

.skip-link:focus {
  transform: translateY(0);
  outline: 2px solid var(--accent-2);
  outline-offset: 2px;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at top, rgba(213, 108, 29, 0.14), transparent 28%),
    radial-gradient(circle at 20% 20%, rgba(13, 122, 114, 0.16), transparent 22%),
    linear-gradient(180deg, #f7f2ea 0%, #efe7da 100%);
  font-family: var(--body-font);
}

a {
  color: inherit;
  text-decoration: none;
}

.site-shell {
  position: relative;
  min-height: 100vh;
  overflow-x: hidden;
}

.site-backdrop {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(29, 36, 48, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(29, 36, 48, 0.03) 1px, transparent 1px);
  background-size: 32px 32px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.6), transparent 85%);
}

.topbar,
.hero-grid,
.content-stack,
.page-intro {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 28px 0 0;
}

.brand {
  font-family: var(--title-font);
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.topbar-links {
  display: flex;
  gap: 18px;
  color: var(--muted);
}

.hero,
.page-header {
  padding-bottom: 32px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(280px, 0.9fr);
  gap: 24px;
  align-items: center;
  padding: 56px 0 24px;
}

.home-hero-grid {
  align-items: stretch;
}

.home-hero-premium {
  padding-bottom: 40px;
}

.home-hero-premium-grid {
  grid-template-columns: minmax(0, 1.05fr) minmax(420px, 0.95fr);
  gap: 28px;
}

.eyebrow,
.section-kicker {
  margin: 0 0 10px;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.8rem;
  font-weight: 700;
}

.section-kicker--zh {
  text-transform: none;
  letter-spacing: 0.08em;
  font-size: 0.85rem;
}

h1,
h2,
h3 {
  margin: 0;
  font-family: var(--title-font);
  line-height: 1.15;
}

h1 {
  font-size: clamp(2.5rem, 5vw, 4.8rem);
  max-width: 11ch;
}

.home-hero .hero-title {
  max-width: min(100%, 14em);
  line-height: 1.12;
}

h2 {
  font-size: clamp(1.6rem, 2.4vw, 2.2rem);
}

h3 {
  font-size: 1.15rem;
}

.lead,
.hero-copy p,
.page-intro p,
.section-card p,
.problem-copy p,
.step-card p,
.bullet-list li {
  color: var(--muted);
  line-height: 1.75;
}

.hero-actions,
.meta-strip,
.hero-panel,
.card-grid,
.two-column-copy,
.problem-body,
.problem-layout,
.nav-links,
.step-list {
  display: grid;
  gap: 18px;
}

.hero-actions {
  grid-template-columns: repeat(2, fit-content(260px));
  margin-top: 28px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 22px;
  border-radius: 999px;
  font-weight: 700;
  transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

.button:hover {
  transform: translateY(-1px);
}

.button-primary {
  background: var(--ink);
  color: #fffdf8;
  box-shadow: 0 16px 30px rgba(29, 36, 48, 0.18);
}

.button-secondary {
  background: rgba(255, 255, 255, 0.5);
  border: 1px solid var(--line);
}

.hero-lead-wide {
  max-width: 42rem;
}

.trust-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.trust-row span {
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.52);
  border: 1px solid rgba(29, 36, 48, 0.08);
  color: var(--muted);
  font-size: 0.92rem;
}

.quick-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.quick-jump-label {
  width: 100%;
  margin: 0;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--muted);
  letter-spacing: 0.04em;
}

.quick-jump a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 16px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.92rem;
  border: 1px solid rgba(13, 122, 114, 0.35);
  background: rgba(13, 122, 114, 0.08);
  color: var(--ink);
  transition: background 180ms ease, border-color 180ms ease, transform 180ms ease;
}

.quick-jump a:hover {
  background: rgba(13, 122, 114, 0.14);
  border-color: rgba(13, 122, 114, 0.5);
  transform: translateY(-1px);
}

.quick-jump a[href="#parents"] {
  border-color: rgba(213, 108, 29, 0.42);
  background: rgba(213, 108, 29, 0.1);
}

.quick-jump a[href="#parents"]:hover {
  background: rgba(213, 108, 29, 0.16);
  border-color: rgba(213, 108, 29, 0.55);
}

.hero-footnote {
  margin: 14px 0 0;
  font-size: 0.9rem;
  color: var(--muted);
  line-height: 1.65;
  max-width: 42em;
}

.home-hero-showcase {
  display: grid;
  gap: 18px;
}

.home-workspace-showcase {
  align-content: stretch;
}

.showcase-card {
  background: rgba(255, 252, 247, 0.86);
  border-radius: 30px;
  border: 1px solid rgba(255, 255, 255, 0.68);
  box-shadow: var(--shadow);
  padding: 22px;
  backdrop-filter: blur(14px);
}

.showcase-preview {
  min-height: 360px;
}

.showcase-preview-product {
  padding: 18px;
}

.workspace-mock {
  display: grid;
  gap: 14px;
  min-height: 100%;
  padding: 16px;
  border-radius: 24px;
  border: 1px solid rgba(29, 36, 48, 0.08);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.92), rgba(250, 246, 238, 0.96));
}

.workspace-topline,
.workspace-problembar,
.workspace-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.workspace-breadcrumb,
.workspace-badge,
.workspace-problembar span,
.workspace-slider label,
.workspace-slider-value {
  font-size: 0.8rem;
  color: var(--muted);
}

.workspace-badge {
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(13, 122, 114, 0.08);
  color: var(--accent);
  font-weight: 700;
}

.workspace-problembar {
  padding: 12px 14px;
  border-radius: 16px;
  border: 1px solid rgba(29, 36, 48, 0.08);
  background: rgba(255, 255, 255, 0.76);
}

.workspace-problembar strong {
  font-size: 0.92rem;
  color: #0f172a;
}

.workspace-main {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(220px, 0.8fr);
  gap: 14px;
  align-items: stretch;
}

.workspace-canvas,
.workspace-panel {
  position: relative;
  border-radius: 18px;
  border: 1px solid rgba(29, 36, 48, 0.08);
  background: rgba(255, 255, 255, 0.8);
}

.workspace-canvas {
  min-height: 340px;
  overflow: hidden;
}

.workspace-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(29, 36, 48, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(29, 36, 48, 0.05) 1px, transparent 1px);
  background-size: 28px 28px;
}

.workspace-axis {
  position: absolute;
  background: rgba(29, 36, 48, 0.18);
}

.workspace-axis-x {
  left: 10%;
  right: 8%;
  bottom: 22%;
  height: 2px;
}

.workspace-axis-y {
  top: 10%;
  bottom: 14%;
  left: 18%;
  width: 2px;
}

.workspace-rect,
.workspace-fold,
.workspace-overlap {
  position: absolute;
  border-radius: 12px;
}

.workspace-rect {
  left: 18%;
  top: 20%;
  width: 43%;
  height: 46%;
  border: 2px solid rgba(217, 119, 6, 0.8);
  background: rgba(245, 158, 11, 0.12);
}

.workspace-fold {
  left: 30%;
  top: 13%;
  width: 34%;
  height: 56%;
  border: 2px solid rgba(13, 122, 114, 0.82);
  background: rgba(15, 118, 110, 0.12);
  transform: skewX(-18deg);
}

.workspace-overlap {
  left: 34%;
  top: 28%;
  width: 24%;
  height: 24%;
  background: rgba(220, 38, 38, 0.14);
  border: 1px solid rgba(185, 28, 28, 0.28);
}

.workspace-point,
.workspace-label {
  position: absolute;
  font-weight: 700;
  color: var(--ink);
}

.workspace-point {
  display: inline-grid;
  place-items: center;
  width: 22px;
  height: 22px;
  border-radius: 999px;
  background: #fffdf8;
  border: 2px solid var(--accent);
  font-size: 0.7rem;
  box-shadow: 0 8px 18px rgba(29, 36, 48, 0.08);
}

.workspace-point-o {
  left: 16%;
  bottom: 19%;
}

.workspace-point-p {
  left: 40%;
  bottom: 19%;
}

.workspace-point-q {
  left: 30%;
  top: 20%;
}

.workspace-label-a {
  left: 58%;
  top: 22%;
  color: var(--accent);
}

.workspace-label-f {
  left: 62%;
  top: 42%;
  color: var(--accent-2);
}

.workspace-panel {
  padding: 16px;
  display: grid;
  gap: 14px;
}

.workspace-panel-head {
  display: grid;
  gap: 6px;
}

.workspace-panel-head span {
  justify-self: start;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(13, 122, 114, 0.08);
  color: var(--accent);
  font-size: 0.74rem;
  font-weight: 700;
}

.workspace-panel-head strong {
  font-size: 0.98rem;
  line-height: 1.4;
}

.workspace-derive {
  display: grid;
  gap: 10px;
  font-family: "SF Mono", "Menlo", "Consolas", monospace;
  font-size: 0.84rem;
  color: var(--muted);
}

.workspace-derive p {
  margin: 0;
  line-height: 1.6;
}

.workspace-derive strong {
  margin-right: 8px;
  color: var(--accent);
}

.workspace-answer {
  padding: 10px 12px;
  border-radius: 14px;
  background: rgba(13, 122, 114, 0.08);
  color: #115e59;
  font-size: 0.84rem;
  font-weight: 700;
}

.workspace-answer span {
  color: #0f172a;
}

.workspace-slider {
  display: grid;
  gap: 8px;
  flex: 1;
}

.workspace-slider-track {
  position: relative;
  height: 8px;
  border-radius: 999px;
  background: rgba(29, 36, 48, 0.1);
  overflow: hidden;
}

.workspace-slider-fill {
  position: absolute;
  inset: 0 auto 0 0;
  width: 58%;
  background: linear-gradient(90deg, #0f766e, #14b8a6);
}

.workspace-slider-thumb {
  position: absolute;
  top: 50%;
  left: 58%;
  width: 16px;
  height: 16px;
  border-radius: 999px;
  background: #fff;
  border: 2px solid var(--accent);
  transform: translate(-50%, -50%);
  box-shadow: 0 6px 16px rgba(29, 36, 48, 0.16);
}

.workspace-lock {
  border: 0;
  border-radius: 999px;
  padding: 10px 16px;
  background: linear-gradient(135deg, #b45309, #d97706);
  color: #fff;
  font-weight: 700;
}

.showcase-browser {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
}

.showcase-browser span {
  width: 11px;
  height: 11px;
  border-radius: 999px;
  background: rgba(29, 36, 48, 0.16);
}

.showcase-canvas {
  position: relative;
  min-height: 286px;
  overflow: hidden;
  border-radius: 24px;
  background:
    radial-gradient(circle at top left, rgba(13, 122, 114, 0.15), transparent 28%),
    linear-gradient(180deg, rgba(248, 244, 236, 0.95), rgba(255, 255, 255, 0.9));
  border: 1px solid rgba(29, 36, 48, 0.08);
}

.showcase-canvas::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(29, 36, 48, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(29, 36, 48, 0.04) 1px, transparent 1px);
  background-size: 34px 34px;
}

.canvas-shape,
.canvas-point,
.canvas-step {
  position: absolute;
}

.canvas-shape-a {
  left: 18%;
  top: 22%;
  width: 170px;
  height: 170px;
  border-radius: 24px;
  border: 3px solid rgba(13, 122, 114, 0.88);
  transform: rotate(-9deg);
}

.canvas-shape-b {
  left: 39%;
  top: 18%;
  width: 150px;
  height: 150px;
  border-radius: 24px;
  border: 3px dashed rgba(213, 108, 29, 0.78);
  transform: rotate(18deg);
}

.canvas-point {
  left: 26%;
  top: 54%;
  width: 18px;
  height: 18px;
  border-radius: 999px;
  background: var(--accent-2);
  box-shadow: 0 0 0 12px rgba(213, 108, 29, 0.14);
}

.canvas-step {
  right: 18px;
  bottom: 18px;
  width: min(240px, calc(100% - 36px));
  padding: 16px 18px;
  border-radius: 18px;
  background: rgba(29, 36, 48, 0.92);
  color: #fff9f0;
}

.canvas-step strong {
  display: block;
  margin-bottom: 6px;
}

.canvas-step p {
  margin: 0;
  color: rgba(255, 249, 240, 0.8);
  line-height: 1.6;
}

.journey-list {
  margin: 8px 0 18px;
  padding-left: 18px;
  color: var(--muted);
  line-height: 1.8;
}

.inline-link {
  color: var(--accent);
  font-weight: 700;
}

.hero-panel,
.card-grid {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.hero-card,
.section-card,
.info-card,
.nav-group,
.slot-card,
.problem-card,
.panel-card,
.step-card,
.summary-card {
  background: var(--paper);
  border: 1px solid rgba(255, 255, 255, 0.65);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

.hero-card,
.info-card,
.slot-card,
.problem-card,
.step-card,
.summary-card {
  padding: 24px;
}

.accent-card {
  background: linear-gradient(160deg, rgba(13, 122, 114, 0.9), rgba(7, 75, 95, 0.95));
  color: #f3f7f7;
}

.accent-card .feature-list,
.accent-card p {
  color: rgba(243, 247, 247, 0.88);
}

.feature-list,
.bullet-list {
  margin: 18px 0 0;
  padding-left: 18px;
}

.content-stack {
  padding: 24px 0 72px;
}

.content-stack > * + * {
  margin-top: 24px;
}

.section-card {
  padding: 28px;
}

.section-emphasis {
  background:
    linear-gradient(135deg, rgba(255, 248, 236, 0.92), rgba(245, 252, 250, 0.92));
}

.section-head {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: end;
  margin-bottom: 22px;
}

.two-column-copy {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.pain-grid,
.audience-grid,
.entry-grid,
.support-layout,
.final-callout-row {
  display: grid;
  gap: 18px;
}

.pain-grid,
.audience-grid,
.entry-grid {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.pain-card,
.audience-card,
.entry-card,
.support-note {
  padding: 22px;
  border-radius: 22px;
  border: 1px solid rgba(29, 36, 48, 0.08);
  background: rgba(255, 255, 255, 0.62);
}

.pain-card h3,
.audience-card h3,
.entry-card h3 {
  margin-bottom: 10px;
}

.audience-card-student {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.84), rgba(242, 248, 255, 0.84));
}

.section-card-premium {
  background:
    linear-gradient(160deg, rgba(255, 252, 247, 0.92), rgba(248, 251, 250, 0.9));
}

.audience-grid-premium,
.entry-grid-premium,
.coverage-grid {
  display: grid;
  gap: 18px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.coverage-card {
  padding: 22px;
  border-radius: 22px;
  border: 1px solid rgba(29, 36, 48, 0.08);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.82), rgba(246, 250, 248, 0.82));
}

.coverage-card h3 {
  margin-bottom: 10px;
}

.audience-card-parent {
  background:
    linear-gradient(180deg, rgba(255, 252, 247, 0.92), rgba(255, 245, 235, 0.9));
  border-color: rgba(213, 108, 29, 0.14);
}

.scope-note {
  margin: 0;
  padding: 16px 20px;
  border-radius: 18px;
  border: 1px dashed rgba(29, 36, 48, 0.16);
  background: rgba(255, 255, 255, 0.45);
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

.scope-note strong {
  color: var(--ink);
}

.support-layout {
  grid-template-columns: minmax(0, 1.2fr) minmax(260px, 0.8fr);
  align-items: start;
}

.support-panel {
  display: grid;
}

.support-note {
  background: linear-gradient(160deg, rgba(13, 122, 114, 0.12), rgba(213, 108, 29, 0.1));
}

.entry-card {
  display: block;
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.entry-card:hover {
  transform: translateY(-2px);
  border-color: rgba(13, 122, 114, 0.28);
}

.entry-card-primary {
  background: linear-gradient(160deg, rgba(29, 36, 48, 0.96), rgba(53, 63, 77, 0.94));
}

.entry-card-primary h3,
.entry-card-primary p {
  color: #fff8ed;
}

.entry-card-primary p {
  color: rgba(255, 248, 237, 0.8);
}

.entry-card-soft {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.82), rgba(248, 251, 250, 0.84));
}

.final-callout {
  background: linear-gradient(160deg, rgba(255, 252, 247, 0.9), rgba(242, 248, 245, 0.92));
}

.final-callout-row {
  grid-template-columns: minmax(0, 1.2fr) fit-content(360px);
  align-items: center;
}

.page-intro {
  padding: 56px 0 12px;
}

.nav-groups {
  display: grid;
  gap: 22px;
}

.nav-group {
  padding: 24px;
}

.group-head {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
  margin-bottom: 20px;
}

.slot-grid {
  display: grid;
  gap: 18px;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.slot-card {
  background: var(--paper-strong);
}

.problem-list {
  display: grid;
  gap: 12px;
  margin-top: 16px;
}

.problem-card {
  padding: 16px 18px;
  background: rgba(255, 255, 255, 0.7);
  border-radius: var(--radius-sm);
  box-shadow: none;
}

.problem-card:hover {
  border-color: rgba(13, 122, 114, 0.3);
  transform: translateY(-1px);
}

.meta-line,
.problem-caption,
.meta-chip {
  color: var(--muted);
  font-size: 0.92rem;
}

.problem-page {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 24px 0 72px;
}

.problem-shell {
  display: grid;
  gap: 24px;
}

.problem-hero {
  padding: 32px;
}

.meta-strip {
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  margin-top: 24px;
}

.meta-item {
  padding: 18px 20px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--line);
}

.meta-item strong {
  display: block;
  margin-bottom: 6px;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
}

.problem-layout {
  grid-template-columns: minmax(0, 1.15fr) minmax(320px, 0.85fr);
}

.panel-card {
  padding: 28px;
}

.problem-layout .panel-card,
.problem-body .panel-card {
  background: var(--paper-strong);
}

.figure-frame {
  padding: 20px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(245, 241, 232, 0.95), rgba(255, 255, 255, 0.88));
}

.figure-frame img,
.source-placeholder {
  width: 100%;
  display: block;
}

.source-placeholder {
  min-height: 220px;
  border-radius: var(--radius-sm);
  border: 1px dashed rgba(29, 36, 48, 0.22);
  background:
    linear-gradient(135deg, rgba(13, 122, 114, 0.1), rgba(213, 108, 29, 0.1)),
    rgba(255, 255, 255, 0.92);
  padding: 24px;
}

.interactive-board {
  position: relative;
  overflow: hidden;
  min-height: 360px;
  padding: 24px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background:
    radial-gradient(circle at top left, rgba(13, 122, 114, 0.12), transparent 30%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.92), rgba(241, 235, 223, 0.95));
}

.interactive-board::before,
.interactive-board::after {
  content: "";
  position: absolute;
  inset: 16px;
  border-radius: calc(var(--radius) - 6px);
  border: 1px solid rgba(29, 36, 48, 0.06);
  pointer-events: none;
}

.geo-stage {
  position: relative;
  height: 300px;
  border-radius: var(--radius-sm);
  background:
    linear-gradient(rgba(29, 36, 48, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(29, 36, 48, 0.05) 1px, transparent 1px),
    #fcfaf5;
  background-size: 36px 36px;
}

.geo-shape {
  position: absolute;
  left: 52%;
  top: 54%;
  width: 150px;
  height: 150px;
  border: 3px solid var(--accent);
  border-radius: 18px;
  transform: translate(-50%, -50%) rotate(var(--shape-rotation, 0deg));
  transition: transform 180ms ease;
}

.geo-point,
.geo-anchor {
  position: absolute;
  width: 18px;
  height: 18px;
  border-radius: 50%;
}

.geo-point {
  left: var(--point-left, 24%);
  top: 62%;
  background: var(--accent-2);
  box-shadow: 0 0 0 10px rgba(213, 108, 29, 0.14);
  transition: left 180ms ease, top 180ms ease;
}

.geo-anchor {
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  background: var(--ink);
}

.label {
  position: absolute;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--ink);
}

.label-anchor {
  left: calc(50% + 18px);
  top: calc(50% - 4px);
}

.label-point {
  left: calc(var(--point-left, 24%) + 18px);
  top: calc(62% - 4px);
  transition: left 180ms ease;
}

.interactive-controls {
  display: grid;
  gap: 14px;
  margin-top: 18px;
}

.control-row {
  display: grid;
  gap: 8px;
}

.control-row label {
  font-weight: 700;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--accent);
}

.step-list {
  margin-top: 18px;
}

.step-card.active-step {
  border: 1px solid rgba(13, 122, 114, 0.28);
  background: linear-gradient(180deg, rgba(13, 122, 114, 0.08), rgba(255, 255, 255, 0.92));
}

.summary-card {
  background: linear-gradient(160deg, rgba(29, 36, 48, 0.96), rgba(49, 58, 71, 0.94));
  color: #f8f3ea;
}

.summary-card p,
.summary-card li {
  color: rgba(248, 243, 234, 0.8);
}

.nav-links {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  margin-top: 18px;
}

.nav-link-card {
  padding: 18px 20px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--line);
}

.muted-note {
  color: var(--muted);
  font-size: 0.95rem;
}

.student-tip {
  margin: -8px 0 18px;
}

@media (max-width: 900px) {
  .hero-grid,
  .problem-layout,
  .support-layout,
  .final-callout-row {
    grid-template-columns: 1fr;
  }

  .home-hero-premium-grid,
  .workspace-main {
    grid-template-columns: 1fr;
  }

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

  h1 {
    max-width: none;
  }

  .section-head,
  .group-head {
    align-items: start;
    flex-direction: column;
  }

  .showcase-preview {
    min-height: 300px;
  }
}

@media (max-width: 640px) {
  .topbar {
    flex-direction: column;
    align-items: start;
    gap: 10px;
  }

  .content-stack,
  .problem-page {
    width: min(100% - 20px, 1120px);
  }

  .hero-grid,
  .page-intro {
    width: min(100% - 20px, 1120px);
  }

  .section-card,
  .panel-card,
  .problem-hero {
    padding: 22px;
  }
}

/* Homepage v2: close to the product mockup direction. */
.home-v2 {
  --home-ink: #0b2f34;
  --home-muted: #5f686d;
  --home-line: rgba(15, 54, 58, 0.13);
  --home-panel: rgba(255, 252, 246, 0.86);
  --home-teal: #0f6b68;
  --home-amber: #c97828;
  background:
    linear-gradient(90deg, rgba(252, 248, 240, 0.96) 0%, rgba(252, 249, 242, 0.86) 45%, rgba(248, 244, 235, 0.96) 100%),
    #fbf8f1;
  color: var(--home-ink);
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

.home-v2 .site-backdrop {
  opacity: 0.38;
  background-size: 40px 40px;
}

.home-v2-hero,
.home-v2-main {
  width: min(1180px, calc(100% - 56px));
  margin: 0 auto;
}

.home-v2-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 24px;
  padding: 36px 0 26px;
}

.home-v2-brand {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  justify-self: start;
  font-family: "Songti SC", "Noto Serif SC", "STSong", serif;
  font-size: 2.55rem;
  font-weight: 700;
  letter-spacing: 0;
}

.home-v2-brand-mark {
  position: relative;
  display: inline-block;
  width: 32px;
  height: 40px;
  border: 3px solid var(--home-teal);
  border-right-width: 1px;
  transform: skewY(-22deg);
  opacity: 0.82;
}

.home-v2-brand-mark::after {
  content: "";
  position: absolute;
  inset: 8px -9px 8px 9px;
  border-right: 2px solid var(--home-teal);
  transform: skewY(22deg);
  opacity: 0.38;
}

.home-v2-nav-links {
  display: flex;
  gap: 56px;
  justify-self: center;
  color: #1f2f33;
  font-size: 1.02rem;
}

.home-v2-nav-links a {
  position: relative;
  padding: 10px 0;
}

.home-v2-nav-links a[aria-current="page"]::after,
.home-v2-nav-links a:hover::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 2px;
  width: 28px;
  height: 2px;
  background: var(--home-teal);
  transform: translateX(-50%);
}

.home-v2-hero-grid {
  display: grid;
  grid-template-columns: 0.74fr 1.26fr;
  gap: 72px;
  align-items: center;
  min-height: 720px;
  padding: 38px 0 68px;
}

.home-v2-copy h1 {
  margin: 0;
  max-width: 7em;
  font-family: "Songti SC", "Noto Serif SC", "STSong", serif;
  font-size: 4.38rem;
  line-height: 1.18;
  letter-spacing: 0;
  color: var(--home-ink);
}

.home-v2-copy h1::first-letter {
  color: inherit;
}

.home-v2-title-accent {
  color: var(--home-amber);
}

.home-v2-lead {
  margin: 30px 0 0;
  max-width: 34.5rem;
  color: #4f5b60;
  font-size: 1.08rem;
  line-height: 2;
}

.home-v2-points {
  display: grid;
  gap: 24px;
  margin-top: 42px;
}

.home-v2-point {
  display: grid;
  grid-template-columns: 46px 1fr;
  gap: 18px;
  align-items: start;
}

.home-v2-point-icon {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(15, 107, 104, 0.28);
  border-radius: 999px;
  color: var(--home-teal);
  font-size: 1.35rem;
  background: rgba(255, 255, 255, 0.58);
}

.home-v2-point strong {
  display: block;
  color: #25383c;
  font-size: 1.08rem;
  margin-bottom: 7px;
}

.home-v2-point p {
  margin: 0;
  color: var(--home-muted);
  line-height: 1.7;
}

.home-v2-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 28px;
  margin-top: 50px;
}

.home-v2-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  min-width: 184px;
  height: 64px;
  border-radius: 7px;
  font-weight: 700;
  font-size: 1.04rem;
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}

.home-v2-button:hover {
  transform: translateY(-1px);
}

.home-v2-button-primary {
  background: linear-gradient(135deg, #0d5958, #0f7772);
  color: #fffdf8;
  box-shadow: 0 16px 34px rgba(15, 107, 104, 0.24);
}

.home-v2-button-secondary {
  border: 1px solid rgba(201, 120, 40, 0.52);
  color: var(--home-amber);
  background: rgba(255, 255, 255, 0.48);
}

.home-v2-product {
  display: block;
  color: inherit;
  padding: 16px;
  border: 1px solid rgba(15, 54, 58, 0.13);
  border-radius: 12px;
  background: rgba(255, 252, 246, 0.9);
  box-shadow: 0 24px 70px rgba(61, 45, 24, 0.13);
}

.product-topbar {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 4px 6px 16px;
  color: #647174;
  font-size: 0.9rem;
}

.product-topbar strong {
  color: #1e3438;
  font-size: 1rem;
}

.product-chip {
  margin-left: auto;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(15, 107, 104, 0.1);
  color: var(--home-teal);
  font-size: 0.78rem;
  font-weight: 700;
}

.product-question {
  padding: 16px 18px;
  border-top: 1px solid var(--home-line);
  border-bottom: 1px solid var(--home-line);
  color: #4f5b60;
  font-size: 0.92rem;
  line-height: 1.85;
}

.product-body {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(216px, 0.72fr);
  gap: 14px;
  padding: 14px 0 0;
}

.product-canvas,
.product-steps {
  border: 1px solid rgba(15, 54, 58, 0.11);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.62);
}

.product-canvas svg {
  display: block;
  width: 100%;
  aspect-ratio: 1.23;
  border-radius: 8px 8px 0 0;
  background: #fffdfa;
}

.product-controls {
  display: grid;
  grid-template-columns: 138px 1fr;
  gap: 10px 16px;
  padding: 16px 18px;
  border-top: 1px solid rgba(15, 54, 58, 0.1);
}

.product-controls label {
  display: contents;
}

.product-controls label > span:first-child {
  color: #4f5b60;
  font-size: 0.9rem;
}

.fake-input {
  justify-self: end;
  padding: 7px 10px;
  border: 1px solid rgba(15, 54, 58, 0.1);
  border-radius: 6px;
  background: #fff;
  color: #4f5b60;
  font-size: 0.88rem;
}

.control-line {
  grid-column: 1 / -1;
  position: relative;
  height: 4px;
  border-radius: 999px;
  background: rgba(15, 54, 58, 0.16);
}

.control-line span {
  position: absolute;
  left: 0;
  top: 0;
  width: 52%;
  height: 100%;
  border-radius: inherit;
  background: var(--home-teal);
}

.control-line-strong span {
  width: 62%;
}

.product-steps {
  padding: 14px;
}

.product-tabs {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(15, 54, 58, 0.1);
  color: #7c8588;
  font-size: 0.86rem;
}

.product-tabs strong {
  color: #273d40;
}

.product-steps ol {
  display: grid;
  gap: 10px;
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.product-steps li {
  display: grid;
  grid-template-columns: 24px 1fr;
  gap: 10px;
  align-items: start;
}

.product-steps li span {
  display: grid;
  place-items: center;
  width: 22px;
  height: 22px;
  border-radius: 5px;
  background: rgba(15, 107, 104, 0.12);
  color: var(--home-teal);
  font-size: 0.78rem;
  font-weight: 700;
}

.product-steps li p {
  margin: 0;
  color: #5f686d;
  font-size: 0.84rem;
  line-height: 1.55;
}

.product-footer {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  padding: 14px 2px 0;
  color: #758083;
  font-size: 0.86rem;
}

.home-v2-main {
  display: grid;
  gap: 42px;
  padding: 0 0 70px;
}

.home-v2-band {
  padding: 48px;
  border: 1px solid rgba(15, 54, 58, 0.1);
  border-radius: 10px;
  background: rgba(255, 252, 246, 0.72);
}

.home-v2-section-head {
  text-align: center;
  margin: 0 auto 42px;
  max-width: 680px;
}

.home-v2-section-head h2,
.home-v2-final h2 {
  margin: 0;
  font-family: "Songti SC", "Noto Serif SC", "STSong", serif;
  font-size: 2.35rem;
  letter-spacing: 0;
  color: var(--home-ink);
}

.home-v2-section-head p,
.home-v2-final p {
  margin: 14px 0 0;
  color: var(--home-muted);
  line-height: 1.8;
}

.home-v2-final p + p {
  margin-top: 10px;
}

.home-v2-step-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 48px;
  align-items: stretch;
}

.home-v2-step {
  min-height: 360px;
  padding: 28px;
  border: 1px solid rgba(15, 54, 58, 0.1);
  border-radius: 9px;
  background: rgba(255, 255, 255, 0.48);
}

.home-v2-step > span {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border: 1px solid rgba(15, 54, 58, 0.12);
  border-radius: 999px;
  color: var(--home-teal);
  font-size: 1.05rem;
}

.home-v2-step:nth-child(2) > span {
  color: var(--home-amber);
}

.home-v2-step h3,
.home-v2-topic h3 {
  margin: 34px 0 12px;
  font-size: 1.24rem;
  color: #283c40;
  letter-spacing: 0;
}

.home-v2-step p,
.home-v2-topic p {
  margin: 0;
  color: var(--home-muted);
  line-height: 1.75;
}

.mini-figure {
  position: relative;
  margin-top: 28px;
  height: 118px;
  border-radius: 8px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.62), rgba(248, 245, 238, 0.62));
}

.mini-figure svg {
  display: block;
  width: 100%;
  height: 100%;
}

.home-v2-topic-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 18px;
}

.home-v2-topic {
  display: block;
  min-height: 300px;
  padding: 22px;
  border: 1px solid rgba(15, 54, 58, 0.1);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.5);
}

.topic-visual {
  height: 116px;
  border-radius: 6px;
  border: 1px solid rgba(15, 54, 58, 0.08);
  background:
    linear-gradient(rgba(15, 54, 58, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(15, 54, 58, 0.06) 1px, transparent 1px),
    #fffdf8;
  background-size: 24px 24px;
  overflow: hidden;
}

.topic-visual svg {
  display: block;
  width: 100%;
  height: 100%;
}

.topic-bg {
  fill: rgba(255, 255, 255, 0.54);
  stroke: rgba(15, 54, 58, 0.08);
}

.topic-axis {
  fill: none;
  stroke: rgba(40, 60, 64, 0.3);
  stroke-width: 1.5;
}

.topic-line {
  fill: none;
  stroke: #0f6b68;
  stroke-width: 2.1;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.topic-line-soft {
  stroke: rgba(15, 107, 104, 0.42);
  stroke-width: 2;
}

.topic-line-amber {
  stroke: rgba(201, 120, 40, 0.55);
}

.topic-line-thick {
  stroke-width: 3.4;
}

.topic-line-thin {
  stroke-width: 1.4;
}

.topic-fill-none {
  fill: none;
}

.topic-fill-soft {
  fill: rgba(15, 107, 104, 0.1);
}

.topic-dot {
  fill: #0f6b68;
}

.topic-dot-amber {
  fill: #c97828;
}

.topic-dot-quiet {
  fill: #fffdf8;
  stroke: #0f6b68;
  stroke-width: 1.3;
}

.topic-dot-ring {
  fill: #0f6b68;
  stroke: rgba(15, 107, 104, 0.18);
  stroke-width: 9;
}

.topic-text {
  fill: #283c40;
  font-size: 12px;
  font-weight: 700;
}

.home-v2-final {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 34px;
  align-items: center;
  padding: 46px 58px;
}

.home-v2-final p {
  max-width: 640px;
}

.back-to-top {
  position: fixed;
  right: clamp(16px, 4vw, 34px);
  bottom: clamp(16px, 4vw, 32px);
  z-index: 40;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(15, 107, 104, 0.34);
  border-radius: 999px;
  background: rgba(255, 252, 246, 0.94);
  color: var(--home-teal);
  font-size: 1.3rem;
  line-height: 1;
  cursor: pointer;
  box-shadow: 0 12px 30px rgba(15, 54, 58, 0.16);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity 180ms ease, transform 180ms ease, visibility 180ms ease, background 180ms ease;
}

.back-to-top:hover {
  background: rgba(15, 107, 104, 0.1);
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:focus-visible {
  outline: 2px solid var(--home-amber);
  outline-offset: 2px;
}

@media (max-width: 1100px) {
  .home-v2-hero-grid,
  .product-body,
  .home-v2-final {
    grid-template-columns: 1fr;
  }

  .home-v2-topic-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  .home-v2-hero,
  .home-v2-main {
    width: min(100% - 28px, 1180px);
  }

  .home-v2-nav {
    grid-template-columns: 1fr;
    justify-items: start;
  }

  .home-v2-brand {
    font-size: 1.8rem;
  }

  .home-v2-nav-links {
    gap: 24px;
    justify-self: start;
  }

  .home-v2-hero-grid {
    min-height: auto;
    gap: 30px;
    padding: 14px 0 34px;
  }

  .home-v2-copy h1 {
    font-size: 2.72rem;
    line-height: 1.12;
    max-width: 8em;
  }

  .home-v2-lead {
    margin-top: 20px;
    font-size: 1rem;
    line-height: 1.78;
  }

  .home-v2-points {
    gap: 18px;
    margin-top: 30px;
  }

  .home-v2-actions {
    gap: 16px;
    margin-top: 34px;
  }

  .home-v2-product {
    padding: 12px;
  }

  .product-question {
    padding: 12px 14px;
    line-height: 1.68;
  }

  .product-canvas svg {
    aspect-ratio: 1.45;
  }

  .home-v2-step-grid,
  .home-v2-topic-grid {
    grid-template-columns: 1fr;
  }

  .home-v2-band {
    padding: 28px;
  }

  .home-v2-main {
    gap: 30px;
    padding-bottom: 48px;
  }

  .home-v2-section-head {
    margin-bottom: 28px;
  }

  .home-v2-section-head h2,
  .home-v2-final h2 {
    font-size: 2.05rem;
    line-height: 1.22;
  }

  .home-v2-step {
    min-height: 0;
    padding: 24px;
  }

  .home-v2-step h3,
  .home-v2-topic h3 {
    margin-top: 22px;
  }

  .mini-figure {
    height: 96px;
    margin-top: 20px;
  }

  .home-v2-topic {
    min-height: 0;
    padding: 22px;
  }

  .topic-visual {
    height: 104px;
  }

  .home-v2-final {
    padding: 30px;
  }

  .product-footer {
    flex-wrap: wrap;
  }
}

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

.library-page {
  --library-ink: #0b2f34;
  --library-muted: #5f686d;
  --library-line: rgba(15, 54, 58, 0.12);
  --library-teal: #0f6b68;
  --library-amber: #c97828;
  --home-ink: var(--library-ink);
  --home-muted: var(--library-muted);
  --home-line: var(--library-line);
  --home-teal: var(--library-teal);
  --home-amber: var(--library-amber);
  background:
    linear-gradient(90deg, rgba(252, 248, 240, 0.96) 0%, rgba(252, 249, 242, 0.86) 45%, rgba(248, 244, 235, 0.96) 100%),
    #fbf8f1;
  color: var(--library-ink);
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

.library-header,
.library-shell {
  width: min(1180px, calc(100% - 56px));
  margin: 0 auto;
}

.library-shell {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  padding: 8px 0 42px;
}

.library-control-panel,
.library-results-panel {
  border: 1px solid rgba(15, 54, 58, 0.1);
  border-radius: 10px;
  background: rgba(255, 252, 246, 0.76);
}

.library-control-panel {
  display: grid;
  gap: 12px;
  padding: 14px;
  position: static;
}

.library-control-block {
  display: grid;
  gap: 8px;
}

.library-control-head,
.library-results-head {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  align-items: end;
}

.library-control-head h2,
.library-filter-row h2,
.library-results-head h2 {
  margin: 0;
  font-family: "Songti SC", "Noto Serif SC", "STSong", serif;
  letter-spacing: 0;
  color: var(--library-ink);
}

.library-control-head h2,
.library-filter-row h2 {
  font-size: 1rem;
}

.library-control-head span,
.library-filter-row p {
  color: var(--library-muted);
  font-size: 0.86rem;
}

.library-city-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.library-city-card,
.library-slot-card,
.library-exam-tab {
  appearance: none;
  cursor: pointer;
  border: 1px solid rgba(15, 54, 58, 0.1);
  background: rgba(255, 255, 255, 0.58);
  color: var(--library-ink);
  transition: border-color 160ms ease, background 160ms ease, transform 160ms ease;
}

.library-city-card:hover,
.library-slot-card:hover,
.library-exam-tab:hover {
  transform: translateY(-1px);
  border-color: rgba(15, 107, 104, 0.34);
}

.library-city-card {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border-radius: 8px;
  text-align: left;
}

.library-city-card strong {
  font-size: 0.94rem;
  font-weight: 800;
}

.library-city-card span,
.library-slot-card strong {
  color: var(--library-muted);
  font-size: 0.8rem;
  font-weight: 600;
}

.library-city-card.is-active,
.library-slot-card.is-active,
.library-exam-tab.is-active {
  background: rgba(15, 107, 104, 0.1);
  border-color: rgba(15, 107, 104, 0.42);
  color: var(--library-teal);
}

.library-slot-grid {
  display: grid;
  grid-template-columns: repeat(8, minmax(0, 1fr));
  gap: 8px;
}

.library-slot-card {
  display: grid;
  gap: 4px;
  justify-items: center;
  padding: 9px 6px;
  border-radius: 8px;
}

.library-slot-card span {
  font-weight: 800;
  font-size: 0.86rem;
}

.library-filter-row {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 12px;
  align-items: center;
  padding-top: 0;
}

.library-filter-row p {
  margin: 2px 0 0;
  line-height: 1.4;
}

.library-exam-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  justify-content: flex-end;
}

.library-exam-tab {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border-radius: 999px;
  font-weight: 800;
  font-size: 0.86rem;
}

.library-exam-tab span {
  display: grid;
  place-items: center;
  min-width: 22px;
  height: 22px;
  padding: 0 7px;
  border-radius: 999px;
  background: rgba(15, 54, 58, 0.08);
  color: var(--library-muted);
  font-size: 0.78rem;
}

.library-results-panel {
  padding: 14px;
}

.library-results-head {
  margin-bottom: 10px;
}

.library-results-head h2 {
  font-size: 1.32rem;
}

.library-count-pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 54px;
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(15, 107, 104, 0.1);
  color: var(--library-teal);
  font-weight: 800;
}

.library-results-list {
  display: grid;
  gap: 8px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.library-problem-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px 10px;
  align-items: start;
  padding: 12px 12px 10px;
  border: 1px solid rgba(15, 54, 58, 0.1);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.58);
  transition: border-color 160ms ease, background 160ms ease, transform 160ms ease;
}

.library-problem-row:hover {
  transform: translateY(-1px);
  border-color: rgba(15, 107, 104, 0.3);
  background: rgba(255, 255, 255, 0.82);
}

.library-problem-main strong {
  display: block;
  color: var(--library-ink);
  font-size: 0.95rem;
  line-height: 1.45;
}

.library-problem-main p {
  margin: 4px 0 0;
  color: var(--library-muted);
  line-height: 1.45;
  font-size: 0.9rem;
}

.library-problem-meta {
  display: flex;
  flex-wrap: wrap;
  grid-column: 1 / 2;
  justify-content: flex-start;
  gap: 6px;
}

.library-problem-meta span {
  display: inline-flex;
  align-items: center;
  padding: 4px 8px;
  border-radius: 999px;
  background: rgba(15, 54, 58, 0.06);
  color: var(--library-muted);
  font-size: 0.78rem;
  font-weight: 700;
}

.library-problem-meta .is-published {
  background: rgba(15, 107, 104, 0.1);
  color: var(--library-teal);
}

.library-problem-arrow {
  justify-self: end;
  align-self: end;
  color: var(--library-teal);
  font-size: 1.1rem;
}

.library-empty {
  padding: 42px 28px;
  border: 1px dashed rgba(15, 54, 58, 0.18);
  border-radius: 8px;
  text-align: center;
  color: var(--library-muted);
  background: rgba(255, 255, 255, 0.42);
}

.library-empty h3 {
  margin: 0 0 10px;
  color: var(--library-ink);
}

.library-empty p {
  margin: 0;
  line-height: 1.7;
}

@media (max-width: 900px) {
  .library-filter-row {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .library-exam-tabs {
    justify-content: flex-start;
  }

  .library-slot-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .library-results-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  .library-header,
  .library-shell {
    width: min(100% - 28px, 1180px);
  }

  .library-shell {
    gap: 10px;
    padding: 4px 0 28px;
  }

  .library-control-panel,
  .library-results-panel {
    padding: 12px;
  }

  .library-city-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
  }

  .library-slot-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .library-results-head {
    align-items: flex-start;
    flex-direction: column;
    gap: 10px;
  }

  .library-results-head h2 {
    font-size: 1.2rem;
  }

  .library-results-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .library-problem-row {
    padding: 10px;
  }
}

@media (max-width: 560px) {
  .library-results-list {
    grid-template-columns: 1fr;
  }
}