:root {
  --color-primary: #6b5bd6;
  --color-primary-pressed: #5847c4;
  --color-primary-soft: #e4def8;
  --color-link: #2f73c8;
  --color-canvas: #fbf6ee;
  --color-page: #ebe4d9;
  --color-surface: #f4ecdf;
  --color-surface-soft: #e7dccc;
  --color-paper: #f8efe0;
  --color-hairline: #d6cabb;
  --color-hairline-strong: #b9aa98;
  --color-ink: #342f29;
  --color-ink-deep: #1f1b17;
  --color-slate: #514a42;
  --color-stone: #71685d;
  --color-muted: #93887b;
  --color-success: #238a4b;
  --color-warning: #c96a1b;
  --color-error: #d83a3a;
  --color-price: #d83a3a;
  --tint-blush: #fbe7ee;
  --tint-peach: #ffe9d8;
  --tint-cream: #fff6dc;
  --tint-mint: #dff4e7;
  --tint-lavender: #e9e4f8;
  --tint-sky: #e1f0fa;
  --tint-sage: #e8f1df;
  --shadow-soft: 0 6px 18px rgba(38, 35, 31, 0.055);
  --shadow-card: 0 12px 28px rgba(38, 35, 31, 0.08);
  --radius-md: 16px;
  --radius-lg: 22px;
  --radius-xl: 28px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  overflow-x: hidden;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--color-ink);
  background:
    linear-gradient(180deg, rgba(224, 211, 197, 0.78) 0, rgba(235, 226, 214, 0.94) 240px, var(--color-page) 560px),
    var(--color-page);
  overflow-x: hidden;
}

button,
input,
select {
  font: inherit;
}

button {
  border: 0;
  background: none;
  color: inherit;
}

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

.page-shell {
  min-height: 100vh;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(250, 246, 239, 0.92);
  border-bottom: 1px solid rgba(216, 207, 194, 0.95);
  backdrop-filter: blur(18px);
}

.header-inner,
.hero-banner,
.filter-panel,
.catalog-panel,
.catalog-layout,
.detail-shell {
  width: min(1600px, calc(100vw - 400px));
  margin: 0 auto;
}

.header-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 13px;
}

.brand-mark {
  width: 46px;
  height: 46px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  color: #fff;
  font-size: 22px;
  font-weight: 700;
  background: var(--color-primary);
  box-shadow: 0 10px 20px rgba(107, 91, 214, 0.22);
}

.brand-copy strong,
.brand-copy span {
  display: block;
}

.brand-copy strong {
  color: var(--color-ink-deep);
  font-size: 22px;
  line-height: 1.2;
  font-weight: 700;
}

.brand-copy span {
  margin-top: 3px;
  color: var(--color-stone);
  font-size: 13px;
}

.header-links {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  min-height: 38px;
  padding: 0 14px;
  border-radius: 12px;
  color: var(--color-slate);
  cursor: pointer;
}

.nav-link:hover,
.nav-link.is-active {
  color: var(--color-primary);
  background: var(--color-primary-soft);
}

.nav-outline {
  border: 1px solid var(--color-hairline);
  background: var(--color-canvas);
  color: var(--color-ink);
}

.nav-login {
  min-height: 38px;
  padding: 0 16px;
  border-radius: 12px;
  background: var(--color-primary);
  color: #fff;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 8px 18px rgba(107, 91, 214, 0.18);
}

.nav-login:hover {
  background: var(--color-primary-pressed);
}

.nav-login:disabled {
  cursor: wait;
  opacity: 0.72;
}

.web-user-chip {
  position: relative;
  min-height: 38px;
}

.web-user-trigger {
  min-height: 38px;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 4px 12px 4px 5px;
  border: 1px solid var(--color-hairline);
  border-radius: 14px;
  background: var(--color-canvas);
  color: var(--color-ink);
  cursor: pointer;
}

.web-user-avatar {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-size: 13px;
  font-weight: 700;
}

.web-user-name {
  max-width: 92px;
  overflow: hidden;
  color: var(--color-slate);
  font-size: 14px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.web-user-arrow {
  width: 7px;
  height: 7px;
  border-right: 1.5px solid var(--color-stone);
  border-bottom: 1.5px solid var(--color-stone);
  transform: rotate(45deg) translateY(-2px);
}

.web-user-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  z-index: 30;
  width: 138px;
  padding: 8px;
  border: 1px solid var(--color-hairline);
  border-radius: 14px;
  background: #fffdf8;
  box-shadow: 0 14px 34px rgba(38, 35, 31, 0.14);
}

.web-user-menu button {
  width: 100%;
  min-height: 34px;
  padding: 0 10px;
  border-radius: 9px;
  color: var(--color-slate);
  text-align: left;
  cursor: pointer;
}

.web-user-menu button:hover {
  color: var(--color-primary);
  background: var(--color-primary-soft);
}

.login-modal-open {
  overflow: hidden;
}

.account-modal-open {
  overflow: hidden;
}

.login-modal {
  position: fixed;
  inset: 0;
  z-index: 80;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 32px;
}

.account-modal {
  position: fixed;
  inset: 0;
  z-index: 82;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 28px;
}

.account-modal.is-open {
  display: flex;
}

.account-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(38, 35, 31, 0.42);
  backdrop-filter: blur(6px);
}

.account-modal-panel {
  position: relative;
  width: min(560px, calc(100vw - 40px));
  max-height: calc(100vh - 56px);
  overflow-y: auto;
  padding: 30px;
  border: 1px solid rgba(231, 226, 218, 0.96);
  border-radius: 24px;
  background: #fffdf8;
  box-shadow: 0 24px 64px rgba(38, 35, 31, 0.2);
}

.account-modal-close {
  position: absolute;
  top: 16px;
  right: 18px;
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 11px;
  color: var(--color-stone);
  font-size: 28px;
  line-height: 1;
  cursor: pointer;
}

.account-modal-close:hover {
  background: var(--color-surface);
  color: var(--color-ink-deep);
}

.account-settings-head {
  padding-right: 38px;
}

.account-settings-head span {
  color: var(--color-primary);
  font-size: 13px;
  font-weight: 700;
}

.account-settings-head h2 {
  margin: 8px 0 8px;
  color: var(--color-ink-deep);
  font-size: 26px;
  line-height: 1.25;
}

.account-settings-head p {
  margin: 0;
  color: var(--color-stone);
  font-size: 14px;
  line-height: 1.7;
}

.account-current-card {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 22px;
  padding: 16px;
  border: 1px solid var(--color-hairline);
  border-radius: 16px;
  background: var(--color-surface);
}

.account-current-avatar {
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-weight: 800;
}

.account-current-card strong,
.account-current-card span {
  display: block;
}

.account-current-card strong {
  color: var(--color-ink-deep);
  font-size: 17px;
}

.account-current-card span {
  margin-top: 4px;
  color: var(--color-stone);
  font-size: 13px;
}

.account-bind-list {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.account-bind-item,
.account-bind-loading,
.account-bind-empty,
.account-bind-error {
  border: 1px solid var(--color-hairline);
  border-radius: 14px;
  background: #fff;
}

.account-bind-item {
  min-height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 14px;
}

.account-bind-item strong,
.account-bind-item span {
  display: block;
}

.account-bind-item strong {
  color: var(--color-ink-deep);
  font-size: 15px;
}

.account-bind-item span {
  margin-top: 4px;
  color: var(--color-stone);
  font-size: 13px;
  line-height: 1.5;
}

.account-bind-item em {
  flex: 0 0 auto;
  padding: 4px 9px;
  border-radius: 999px;
  background: var(--tint-mint);
  color: var(--color-success);
  font-size: 12px;
  font-style: normal;
  font-weight: 700;
}

.account-bind-item button {
  flex: 0 0 auto;
  min-height: 34px;
  padding: 0 14px;
  border-radius: 11px;
  background: var(--color-primary);
  color: #fff;
  font-weight: 700;
  cursor: pointer;
}

.account-bind-item.is-disabled {
  background: var(--color-surface);
}

.account-bind-item.is-disabled em {
  background: var(--color-surface-soft);
  color: var(--color-muted);
}

.account-bind-loading,
.account-bind-empty,
.account-bind-error {
  padding: 16px;
  color: var(--color-stone);
  font-size: 14px;
}

.account-bind-error {
  color: var(--color-error);
}

.account-bind-qr-panel {
  margin-top: 18px;
  padding: 16px;
  border: 1px solid var(--color-hairline);
  border-radius: 16px;
  background: var(--color-paper);
}

.account-bind-qr-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
}

.account-bind-qr-head strong {
  color: var(--color-ink-deep);
}

.account-bind-qr-head span {
  color: var(--color-stone);
  font-size: 13px;
}

.account-bind-qr-box {
  width: 238px;
  height: 238px;
  display: grid;
  place-items: center;
  margin: 0 auto;
  overflow: hidden;
  border: 1px solid var(--color-hairline);
  border-radius: 14px;
  background: #fff;
}

.account-bind-qr-box iframe {
  width: 238px !important;
  height: 238px !important;
}

.login-modal.is-open {
  display: flex;
}

.login-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(38, 35, 31, 0.46);
  backdrop-filter: blur(6px);
}

.login-modal-panel {
  position: relative;
  width: min(760px, calc(100vw - 48px));
  height: 540px;
  display: grid;
  grid-template-columns: 300px 1fr;
  overflow: hidden;
  border: 1px solid rgba(231, 226, 218, 0.9);
  border-radius: 30px;
  background: #fff;
  box-shadow: 0 24px 64px rgba(38, 35, 31, 0.22);
}

.login-modal-close {
  position: absolute;
  top: 22px;
  right: 24px;
  z-index: 2;
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  color: #817a70;
  font-size: 32px;
  line-height: 1;
  cursor: pointer;
}

.login-modal-close:hover {
  background: var(--color-surface);
  color: var(--color-ink-deep);
}

.login-brand-panel {
  position: relative;
  overflow: hidden;
  padding: 38px 34px;
  border-right: 1px solid rgba(255, 191, 109, 0.28);
  background:
    radial-gradient(circle at 68% 8%, rgba(255, 207, 139, 0.42) 0 8px, transparent 9px),
    radial-gradient(circle at 16% 84%, rgba(255, 190, 100, 0.42) 0 14px, transparent 15px),
    linear-gradient(180deg, #fff8ea 0%, #fffdf8 56%, #fff4df 100%);
}

.login-brand-panel::before,
.login-brand-panel::after {
  content: "";
  position: absolute;
  border-radius: 999px;
  background: rgba(255, 171, 87, 0.2);
}

.login-brand-panel::before {
  width: 240px;
  height: 240px;
  left: -130px;
  bottom: -110px;
}

.login-brand-panel::after {
  width: 120px;
  height: 120px;
  right: 74px;
  bottom: 118px;
}

.login-product-mark {
  width: 58px;
  height: 58px;
  display: grid;
  place-items: center;
  border-radius: 16px;
  background: #ff7a18;
  color: #fff;
  font-size: 34px;
  font-weight: 800;
  box-shadow: 0 12px 24px rgba(255, 122, 24, 0.22);
}

.login-product-name {
  position: absolute;
  top: 48px;
  left: 104px;
  color: var(--color-ink-deep);
  font-size: 22px;
  font-weight: 800;
}

.login-product-subtitle {
  position: absolute;
  top: 78px;
  left: 106px;
  color: var(--color-muted);
  font-size: 13px;
}

.login-brand-panel h2 {
  margin: 58px 0 0;
  color: var(--color-ink-deep);
  font-size: 28px;
  line-height: 1.25;
}

.login-accent {
  width: 66px;
  height: 8px;
  margin: 26px 0 34px;
  background: #ff821c;
}

.login-points {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 18px;
  margin: 0;
  padding: 0;
  list-style: none;
  color: var(--color-slate);
  font-size: 18px;
  line-height: 1.3;
}

.login-points li {
  display: flex;
  align-items: center;
  gap: 18px;
}

.login-points li::before {
  content: "";
  width: 28px;
  height: 28px;
  flex: 0 0 auto;
  border-radius: 50%;
  background:
    linear-gradient(135deg, transparent 49%, #fff 50%) 8px 13px / 8px 4px no-repeat,
    linear-gradient(45deg, transparent 46%, #fff 47%) 13px 8px / 9px 14px no-repeat,
    #ffa24b;
}

.login-illustration {
  position: absolute;
  left: 80px;
  right: 26px;
  bottom: 0;
  height: 190px;
}

.login-book {
  position: absolute;
  left: 96px;
  right: 24px;
  bottom: -12px;
  height: 92px;
  border-radius: 52% 44% 0 0;
  background:
    linear-gradient(172deg, rgba(255,255,255,0.9) 0 28%, transparent 29%),
    linear-gradient(180deg, #ffd8a9, #ff9b56);
  box-shadow: inset 0 12px 0 rgba(255,255,255,0.42);
}

.login-cap {
  position: absolute;
  left: 32px;
  bottom: 94px;
  width: 144px;
  height: 78px;
  transform: rotate(-22deg);
  background: #ff9d58;
  clip-path: polygon(0 30%, 58% 0, 100% 22%, 40% 54%);
  filter: drop-shadow(0 12px 14px rgba(255, 122, 24, 0.22));
}

.login-content-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  padding: 38px 46px 28px;
  background: #fff;
}

.login-content-panel h2 {
  margin: 0 0 22px;
  color: var(--color-ink-deep);
  font-size: 36px;
  line-height: 1.1;
}

.login-mode-tabs {
  width: 100%;
  display: none;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-bottom: 24px;
  padding: 4px;
  border: 1px solid var(--color-hairline);
  border-radius: 14px;
  background: var(--color-surface);
}

.login-mode-tabs button {
  min-height: 36px;
  border-radius: 11px;
  color: var(--color-slate);
  cursor: pointer;
}

.login-mode-tabs button.is-active {
  background: #fffdf8;
  color: var(--color-primary);
  box-shadow: 0 4px 12px rgba(38, 35, 31, 0.06);
}

.login-form {
  width: 100%;
  min-height: 372px;
  display: none;
}

.login-form.is-active {
  display: flex;
  flex-direction: column;
}

.login-form[data-login-panel="account"] {
  padding-top: 48px;
}

.login-field {
  display: grid;
  gap: 6px;
  margin-bottom: 12px;
  color: var(--color-slate);
  font-size: 14px;
}

.login-field input {
  width: 100%;
  height: 42px;
  padding: 0 14px;
  border: 1px solid var(--color-hairline);
  border-radius: 12px;
  background: #fffdf8;
  color: var(--color-ink);
  outline: none;
}

.login-field input:focus {
  border-color: rgba(107, 91, 214, 0.52);
  box-shadow: 0 0 0 3px rgba(107, 91, 214, 0.12);
}

.login-submit {
  width: 100%;
  height: 44px;
  margin-top: 2px;
  border-radius: 12px;
  background: var(--color-primary);
  color: #fff;
  font-weight: 700;
  cursor: pointer;
}

.login-submit:disabled {
  opacity: 0.72;
  cursor: wait;
}

.login-switch-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: auto;
  padding-top: 14px;
}

.login-switch-row button {
  color: var(--color-link);
  font-size: 14px;
  cursor: pointer;
}

.login-method-label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
  color: var(--color-slate);
  font-size: 17px;
}

.login-wechat-icon {
  width: 34px;
  height: 30px;
  display: inline-flex;
  color: #07c160;
}

.login-wechat-icon svg {
  width: 100%;
  height: 100%;
  display: block;
  fill: currentColor;
}

.login-wechat-icon circle {
  fill: #fff;
}

.login-qr-box {
  width: 276px;
  height: 276px;
  align-self: center;
  display: grid;
  place-items: center;
  overflow: hidden;
  border: 1px solid #e7e2da;
  border-radius: 8px;
  background: #fff;
}

.login-qr-box iframe {
  width: 276px !important;
  height: 276px !important;
  border: 0;
}

.login-qr-placeholder {
  width: 100%;
  height: 100%;
  display: grid;
  place-items: center;
  gap: 8px;
  padding: 32px;
  color: var(--color-stone);
  text-align: center;
  line-height: 1.6;
}

.login-qr-placeholder strong,
.login-qr-placeholder span {
  display: block;
}

.login-qr-tip {
  margin: 12px 0 0;
  color: var(--color-muted);
  font-size: 15px;
}

.login-password-rule {
  min-height: 18px;
  margin: -4px 0 10px;
  color: var(--color-stone);
  font-size: 12px;
  line-height: 1.5;
}

.login-password-rule.is-error {
  color: var(--color-error);
}

.home-view,
.detail-view {
  display: none;
  padding-bottom: 24px;
}

.home-view.is-active,
.detail-view.is-active {
  display: block;
}

.hero-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 10px 0;
}

.hero-copy {
  display: none;
}

.hero-copy h1 {
  margin: 0;
  max-width: 560px;
  color: var(--color-ink-deep);
  font-size: clamp(28px, 3vw, 38px);
  line-height: 1.18;
  letter-spacing: 0;
}

.hero-copy p {
  max-width: 520px;
  margin: 10px 0 0;
  color: var(--color-slate);
  font-size: 15px;
  line-height: 1.65;
}

.hero-search {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.search-box {
  order: 2;
  width: min(62%, 700px);
  min-height: 58px;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 0 22px;
  border-radius: 18px;
  border: 1px solid var(--color-hairline);
  background: rgba(250, 246, 239, 0.92);
  box-shadow: var(--shadow-card);
}

.search-icon {
  width: 26px;
  height: 26px;
  color: var(--color-stone);
  display: inline-flex;
}

.search-icon svg {
  width: 100%;
  height: 100%;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
}

.search-box input {
  flex: 1;
  min-width: 0;
  border: 0;
  outline: none;
  background: transparent;
  color: var(--color-ink);
  font-size: 18px;
}

.search-box input::placeholder {
  color: var(--color-muted);
}

.stage-tabs,
.subject-tabs,
.grade-strip,
.resource-strip,
.thumb-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.stage-tabs {
  order: 1;
  flex: 0 0 auto;
}

.stage-tab,
.subject-tab,
.detail-tab {
  position: relative;
  min-height: 40px;
  padding: 0 14px;
  border-radius: 999px;
  color: var(--color-slate);
  cursor: pointer;
  font-size: 15px;
  font-weight: 600;
}

.stage-tab,
.subject-tab {
  background: rgba(244, 236, 223, 0.82);
  border: 1px solid var(--color-hairline);
}

.stage-tab:hover,
.subject-tab:hover,
.stage-tab.is-active,
.subject-tab.is-active {
  color: var(--color-primary);
  border-color: rgba(107, 91, 214, 0.3);
  background: var(--color-primary-soft);
}

.filter-panel,
.catalog-panel,
.book-card,
.related-panel,
.detail-content-card {
  border: 1px solid var(--color-hairline);
  background: linear-gradient(180deg, #fbf7ef 0%, #f7f0e6 100%);
  box-shadow: var(--shadow-soft);
}

.filter-panel {
  display: grid;
  grid-template-rows: auto auto;
  border-radius: var(--radius-xl);
  overflow: hidden;
  padding: 18px 28px 24px;
}

.filter-row {
  position: relative;
  z-index: 3;
  min-height: 54px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  width: 100%;
}

.subject-group {
  flex: 1 1 auto;
  min-width: 0;
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.filter-label,
.version-select-wrap span {
  color: var(--color-stone);
  font-size: 14px;
  font-weight: 600;
}

.version-select-wrap {
  flex: 0 0 auto;
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.version-select-wrap select {
  min-width: 132px;
  min-height: 42px;
  padding: 0 34px 0 14px;
  border-radius: 14px;
  border: 1px solid var(--color-hairline);
  background: rgba(241, 232, 219, 0.92);
  color: var(--color-ink);
  outline: none;
}

.grade-carousel {
  position: relative;
  margin-top: 10px;
  width: 100%;
  min-width: 0;
  overflow: hidden;
}

.grade-strip-viewport {
  width: 100%;
  min-width: 0;
  overflow-x: auto;
  overflow-y: hidden;
  overscroll-behavior-x: contain;
  scroll-behavior: smooth;
  scrollbar-width: none;
  padding: 18px 18px 14px;
}

.grade-strip-viewport::-webkit-scrollbar {
  display: none;
}

.grade-strip {
  flex-wrap: nowrap;
  width: max-content;
  max-width: none;
  min-width: 0;
  padding: 0;
  gap: 18px;
}

.grade-scroll-button {
  position: absolute;
  top: 50%;
  z-index: 2;
  width: 54px;
  height: 54px;
  display: grid;
  place-items: center;
  border-radius: 999px;
  border: 1px solid rgba(216, 207, 194, 0.72);
  background: rgba(248, 240, 229, 0.9);
  box-shadow: 0 8px 20px rgba(38, 35, 31, 0.09);
  color: var(--color-stone);
  cursor: pointer;
  transform: translateY(-50%);
  transition: opacity 0.16s ease, transform 0.16s ease, color 0.16s ease;
}

.grade-scroll-button:hover {
  color: var(--color-primary);
  transform: translateY(-50%) scale(1.04);
}

.grade-scroll-button:disabled {
  opacity: 0;
  pointer-events: none;
}

.grade-scroll-button-prev {
  left: 10px;
}

.grade-scroll-button-next {
  right: 10px;
}

.grade-scroll-button span {
  width: 15px;
  height: 15px;
  border-top: 3px solid currentColor;
  border-right: 3px solid currentColor;
  transform: rotate(45deg);
}

.grade-scroll-button-prev span {
  transform: rotate(225deg);
}

.grade-card {
  position: relative;
  flex: 0 0 172px;
  width: 172px;
  height: 186px;
  display: block;
  padding: 0;
  overflow: hidden;
  border-radius: 14px;
  border: 2px solid transparent;
  background: #ebe5dc;
  cursor: pointer;
  transform-origin: center bottom;
  transition: transform 0.18s ease, border-color 0.18s ease, box-shadow 0.18s ease, filter 0.18s ease;
}

.grade-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 22px rgba(255, 121, 31, 0.12);
}

.grade-card.is-active {
  z-index: 3;
  border-color: #ff930f;
  transform: translateY(-9px) scale(1.08);
  box-shadow: 0 0 0 3px rgba(255, 147, 15, 0.12), 0 18px 34px rgba(255, 121, 31, 0.22);
}

.grade-book {
  width: 100%;
  height: 100%;
  display: block;
  border-radius: 12px;
  object-fit: cover;
  box-shadow: 0 8px 18px rgba(38, 35, 31, 0.075);
}

.grade-card-label {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  min-height: 34px;
  display: grid;
  place-items: center;
  padding: 2px 10px 4px;
  color: #fff;
  font-size: 18px;
  font-weight: 800;
  line-height: 1;
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.25);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.02) 0%, rgba(92, 91, 88, 0.78) 36%, rgba(80, 79, 77, 0.96) 100%);
}

.grade-card.is-active .grade-card-label {
  background: linear-gradient(180deg, rgba(255, 198, 118, 0.08) 0%, rgba(255, 148, 45, 0.84) 34%, #ff720f 100%);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.catalog-panel {
  border-radius: var(--radius-xl);
  margin-top: 10px;
  overflow: hidden;
  position: relative;
}

.catalog-layout {
  display: grid;
  width: 100%;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 0;
  margin-top: 0;
  align-items: stretch;
}

.catalog-sidebar,
.catalog-main,
.related-panel,
.detail-content-card,
.book-card {
  border-radius: var(--radius-xl);
}

.catalog-sidebar {
  align-self: stretch;
  position: sticky;
  top: 72px;
  min-height: auto;
  max-height: none;
  border-right: 1px solid var(--color-hairline);
  overflow: hidden;
}

.sidebar-head {
  min-height: 98px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 20px;
  border-bottom: 1px solid var(--color-hairline);
}

.sidebar-head strong,
.sidebar-head span {
  display: block;
}

.sidebar-head strong {
  color: var(--color-ink-deep);
  font-size: 18px;
}

.sidebar-head span {
  margin-top: 3px;
  color: var(--color-stone);
  font-size: 12px;
}

.diamond {
  flex: 0 0 auto;
  width: 12px;
  height: 12px;
  border-radius: 3px;
  background: var(--color-primary);
  transform: rotate(45deg);
}

.unit-list {
  display: grid;
  padding: 10px;
}

.unit-item {
  min-height: 46px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 0 12px;
  border-radius: 14px;
  color: var(--color-slate);
  cursor: pointer;
}

.unit-item:hover,
.unit-item.is-active {
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-weight: 700;
}

.unit-count {
  min-width: 28px;
  height: 24px;
  padding: 0 8px;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface-soft);
  color: var(--color-stone);
  font-size: 12px;
}

.unit-item.is-active .unit-count {
  background: var(--color-canvas);
  color: var(--color-primary);
}

.catalog-main {
  min-width: 0;
  display: flex;
  flex-direction: column;
  max-height: none;
  overflow-y: visible;
  overflow-x: hidden;
  padding: 0;
  scroll-behavior: smooth;
  scrollbar-width: thin;
  scrollbar-color: rgba(147, 136, 123, 0.42) transparent;
}

.catalog-main::-webkit-scrollbar {
  width: 8px;
}

.catalog-main::-webkit-scrollbar-track {
  background: transparent;
}

.catalog-main::-webkit-scrollbar-thumb {
  border-radius: 999px;
  background: rgba(147, 136, 123, 0.32);
}

.catalog-toolbar {
  position: sticky;
  top: 0;
  z-index: 2;
  flex: 0 0 auto;
  min-height: 98px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  margin: 0;
  padding: 0 32px;
  background: rgba(251, 247, 239, 0.96);
  border-bottom: 1px solid rgba(216, 207, 194, 0.58);
  backdrop-filter: blur(10px);
}

.catalog-book-title {
  min-width: 0;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--color-ink-deep);
  font-size: 26px;
  line-height: 1.2;
}

.catalog-book-title strong {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.catalog-book-icon {
  width: 18px;
  height: 26px;
  border-radius: 4px 4px 2px 2px;
  background: linear-gradient(180deg, #ff8e33, #ff7020);
  box-shadow: inset 4px 0 0 rgba(255, 255, 255, 0.82);
}

.catalog-search {
  flex: 0 0 300px;
  min-height: 44px;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 14px;
  border: 1px solid var(--color-hairline);
  border-radius: 10px;
  background: rgba(241, 232, 219, 0.86);
}

.catalog-search input {
  flex: 1;
  min-width: 0;
  border: 0;
  outline: none;
  background: transparent;
  color: var(--color-ink);
  font-size: 15px;
}

.catalog-search input::placeholder {
  color: var(--color-muted);
}

.catalog-search-icon {
  flex: 0 0 auto;
  width: 22px;
  height: 22px;
  color: var(--color-muted);
  display: inline-flex;
}

.catalog-search-icon svg {
  width: 100%;
  height: 100%;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
}

.catalog-head {
  flex: 0 0 auto;
  padding: 26px 32px 20px;
}

.catalog-head h2,
.catalog-head p,
.detail-title,
.detail-tip,
.info-block h3,
.files-block h3,
.related-head h3,
.feature-block h3,
.faq-list h3 {
  margin: 0;
}

.catalog-head h2 {
  color: var(--color-ink-deep);
  font-size: 28px;
  line-height: 1.25;
}

.catalog-head p {
  margin-top: 8px;
  color: var(--color-stone);
  font-size: 15px;
}

.lesson-grid {
  flex: 0 0 auto;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  overflow-y: visible;
  overflow-x: hidden;
  padding: 0 32px;
}

.lesson-card {
  min-width: 0;
  overflow: hidden;
  border: 1px solid rgba(216, 207, 194, 0.72);
  border-radius: 16px;
  background: rgba(251, 247, 239, 0.9);
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.lesson-card:hover,
.lesson-card:focus-visible {
  outline: none;
  transform: translateY(-2px);
  border-color: rgba(107, 91, 214, 0.35);
  box-shadow: 0 10px 24px rgba(38, 35, 31, 0.1);
}

.lesson-cover-wrap {
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--tint-sky);
}

.lesson-cover-wrap img,
.preview-stage img,
.related-thumb img,
.thumb-button img {
  width: 100%;
  height: 100%;
  display: block;
}

.lesson-cover-wrap img,
.related-thumb img,
.thumb-button img {
  object-fit: cover;
}

.lesson-body {
  padding: 14px 15px 16px;
}

.lesson-title {
  min-height: 48px;
  color: var(--color-ink-deep);
  font-size: 16px;
  font-weight: 700;
  line-height: 1.5;
}

.lesson-meta {
  margin-top: 7px;
  color: var(--color-stone);
  font-size: 13px;
}

.lesson-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: 14px;
}

.lesson-tags {
  min-width: 0;
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.lesson-tags span,
.status-chip,
.resource-pill-tag {
  border-radius: 999px;
  font-size: 12px;
  font-weight: 700;
}

.lesson-tags span {
  padding: 3px 8px;
  background: var(--tint-cream);
  color: var(--color-warning);
}

.lesson-price {
  flex: 0 0 auto;
  color: var(--color-price);
  font-size: 16px;
}

.detail-shell {
  padding-top: 24px;
}

.detail-back-row {
  margin-bottom: 14px;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--color-stone);
  cursor: pointer;
}

.back-link::before {
  content: "";
  width: 9px;
  height: 9px;
  border-left: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg);
}

.detail-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 22px;
}

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

.detail-sidebar {
  display: grid;
  gap: 18px;
  align-self: start;
}

.detail-topbar {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
}

.detail-title {
  color: var(--color-ink-deep);
  font-size: clamp(30px, 4vw, 44px);
  line-height: 1.22;
}

.detail-tip {
  margin-top: 10px;
  color: var(--color-stone);
  font-size: 15px;
}

.download-button {
  flex: 0 0 auto;
  min-width: 168px;
  min-height: 54px;
  padding: 0 24px;
  border-radius: 16px;
  background: var(--color-primary);
  color: #fff;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 12px 24px rgba(107, 91, 214, 0.22);
}

.download-button:hover {
  background: var(--color-primary-pressed);
}

.preview-panel {
  overflow: hidden;
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-xl);
  background: var(--color-canvas);
  box-shadow: var(--shadow-card);
}

.preview-stage {
  min-height: 520px;
  display: grid;
  place-items: center;
  background: linear-gradient(180deg, var(--color-paper), var(--color-surface-soft));
}

.preview-stage img {
  object-fit: contain;
  background: var(--color-paper);
}

.thumb-row {
  padding: 2px;
}

.thumb-button {
  width: 116px;
  height: 74px;
  padding: 0;
  overflow: hidden;
  border-radius: 14px;
  border: 2px solid transparent;
  background: var(--color-surface-soft);
  cursor: pointer;
}

.thumb-button.is-active {
  border-color: var(--color-primary);
}

.resource-strip {
  display: flex;
  flex-wrap: nowrap;
  gap: 12px;
  overflow-x: auto;
  overflow-y: hidden;
  padding: 2px 2px 8px;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.resource-pill {
  flex: 0 0 300px;
  width: 300px;
  min-height: 54px;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 14px;
  border: 1px solid var(--color-hairline);
  border-radius: 16px;
  background: var(--color-canvas);
  color: var(--color-ink);
  scroll-snap-align: start;
  text-align: left;
}

.preview-pdf-pill {
  cursor: pointer;
}

.preview-pdf-pill:hover,
.preview-pdf-file:hover {
  border-color: var(--color-primary);
  background: var(--color-paper);
}

.resource-pill-icon,
.resource-file-icon {
  display: grid;
  place-items: center;
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-weight: 800;
}

.resource-pill-icon {
  width: 26px;
  height: 26px;
  border-radius: 9px;
  font-size: 12px;
}

.resource-pill-name {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.resource-pill-tag {
  margin-left: auto;
  padding: 3px 8px;
  background: var(--tint-sky);
  color: var(--color-link);
}

.detail-tabs {
  display: flex;
  gap: 10px;
  padding-top: 4px;
}

.detail-tab {
  border: 1px solid var(--color-hairline);
  background: var(--color-canvas);
}

.detail-tab.is-active {
  color: var(--color-primary);
  border-color: rgba(107, 91, 214, 0.34);
  background: var(--color-primary-soft);
}

.detail-content-card {
  padding: 24px 28px 30px;
}

.detail-tab-panel {
  display: none;
}

.detail-tab-panel.is-active {
  display: block;
}

.info-columns {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 28px;
}

.info-block {
  display: grid;
  align-content: start;
  gap: 16px;
}

.info-block h3,
.files-block h3,
.feature-block h3,
.related-head h3,
.faq-list h3 {
  color: var(--color-ink-deep);
  font-size: 18px;
}

.detail-list {
  display: grid;
  gap: 10px;
}

.detail-item {
  display: grid;
  grid-template-columns: 92px minmax(0, 1fr);
  gap: 12px;
  line-height: 1.65;
  font-size: 15px;
}

.detail-item strong {
  color: var(--color-stone);
  font-weight: 600;
}

.description-box,
.feature-block,
.resource-files,
.faq-list {
  color: var(--color-slate);
  line-height: 1.75;
}

.description-box p {
  margin: 0 0 12px;
}

.feature-block,
.files-block {
  margin-top: 28px;
}

.feature-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 14px;
}

.feature-item {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  padding: 12px 14px;
  border-radius: 16px;
  background: var(--color-paper);
  border: 1px solid var(--color-hairline);
}

.feature-item::before {
  content: "";
  flex: 0 0 auto;
  width: 8px;
  height: 8px;
  margin-top: 9px;
  border-radius: 50%;
  background: var(--color-primary);
}

.resource-files {
  display: flex;
  flex-wrap: nowrap;
  gap: 12px;
  margin-top: 14px;
  overflow-x: auto;
  overflow-y: hidden;
  padding: 2px 2px 10px;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.resource-file {
  flex: 0 0 360px;
  width: 360px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 15px 16px;
  border-radius: 18px;
  border: 1px solid var(--color-hairline);
  background: var(--color-surface);
  color: var(--color-ink);
  scroll-snap-align: start;
  text-align: left;
}

button.resource-file {
  cursor: pointer;
}

.resource-file-info {
  min-width: 0;
  display: flex;
  align-items: center;
  gap: 13px;
}

.resource-file-icon {
  width: 42px;
  height: 42px;
  border-radius: 14px;
  font-size: 12px;
}

.resource-file-name {
  min-width: 0;
}

.resource-file-name strong,
.resource-file-name span {
  display: block;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.resource-file-name span {
  margin-top: 4px;
  color: var(--color-stone);
  font-size: 13px;
}

.status-chip {
  flex: 0 0 auto;
  padding: 5px 10px;
  background: var(--tint-mint);
  color: var(--color-success);
}

.preview-chip {
  background: var(--color-primary-soft);
  color: var(--color-primary);
}

.faq-list {
  display: grid;
  gap: 14px;
}

.faq-list article {
  padding: 18px;
  border: 1px solid var(--color-hairline);
  border-radius: 18px;
  background: var(--color-paper);
}

.faq-list p {
  margin: 8px 0 0;
  color: var(--color-slate);
}

.book-card {
  padding: 18px;
}

.book-card-grid {
  display: grid;
  grid-template-columns: 98px minmax(0, 1fr);
  gap: 15px;
  align-items: center;
}

.book-cover {
  width: 98px;
  height: 126px;
  overflow: hidden;
  border-radius: 16px;
  box-shadow: 0 12px 24px rgba(38, 35, 31, 0.12);
}

.book-cover img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

.book-meta span {
  color: var(--color-stone);
  font-size: 12px;
  font-weight: 700;
}

.book-meta h3 {
  margin: 7px 0 0;
  color: var(--color-ink-deep);
  font-size: 17px;
  line-height: 1.4;
}

.book-meta p {
  margin: 7px 0 0;
  color: var(--color-stone);
}

.related-panel {
  padding: 16px 14px;
}

.related-head {
  padding: 4px 4px 14px;
}

.related-list {
  display: grid;
  gap: 8px;
  max-height: 760px;
  overflow: auto;
}

.related-item {
  display: grid;
  grid-template-columns: 74px minmax(0, 1fr);
  gap: 11px;
  padding: 8px;
  border-radius: 16px;
  cursor: pointer;
  text-align: left;
}

.related-item:hover,
.related-item.is-active {
  background: var(--color-primary-soft);
}

.related-thumb {
  height: 52px;
  overflow: hidden;
  border-radius: 12px;
  background: var(--tint-sky);
}

.related-title {
  color: var(--color-ink);
  font-size: 13px;
  font-weight: 650;
  line-height: 1.45;
}

.related-meta {
  margin-top: 4px;
  color: var(--color-stone);
  font-size: 12px;
}

.preview-placeholder,
.empty-state,
.error-state {
  padding: 44px 22px;
  color: var(--color-stone);
  text-align: center;
  border-radius: 18px;
  background: var(--color-paper);
  border: 1px dashed var(--color-hairline-strong);
}

.empty-state.compact,
.error-state.compact {
  padding: 18px;
}

.error-state {
  color: var(--color-error);
  background: #fff7f7;
}

.pdf-modal-open {
  overflow: hidden;
}

.pdf-modal {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 28px;
}

.pdf-modal.is-open {
  display: flex;
}

.pdf-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(38, 35, 31, 0.46);
}

.pdf-modal-panel {
  position: relative;
  z-index: 1;
  width: min(1120px, 100%);
  height: min(88vh, 900px);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border-radius: 20px;
  border: 1px solid var(--color-hairline);
  background: var(--color-canvas);
  box-shadow: 0 24px 64px rgba(38, 35, 31, 0.18);
}

.pdf-modal.is-maximized {
  padding: 10px;
}

.pdf-modal.is-maximized .pdf-modal-panel {
  width: min(1680px, 100%);
  height: calc(100vh - 20px);
  border-radius: 16px;
}

.pdf-modal-head {
  flex: 0 0 auto;
  min-height: 58px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 10px 14px 10px 18px;
  border-bottom: 1px solid var(--color-hairline);
  background: var(--color-paper);
}

.pdf-modal-kicker {
  display: block;
  color: var(--color-primary);
  font-size: 11px;
  font-weight: 700;
  line-height: 1.2;
}

.pdf-modal-head h2 {
  margin: 2px 0 0;
  max-width: min(720px, 58vw);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  color: var(--color-ink-deep);
  font-size: 16px;
  line-height: 1.28;
}

.pdf-modal-actions {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.pdf-modal-action {
  flex: 0 0 auto;
  min-height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  padding: 0 12px;
  border-radius: 12px;
  border: 1px solid var(--color-hairline);
  background: var(--color-canvas);
  color: var(--color-slate);
  cursor: pointer;
  font-size: 14px;
  font-weight: 650;
}

.pdf-modal-action:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.pdf-action-icon {
  position: relative;
  width: 14px;
  height: 14px;
  display: inline-block;
}

.pdf-action-icon-maximize {
  border: 2px solid currentColor;
  border-radius: 3px;
}

.pdf-modal.is-maximized .pdf-action-icon-maximize::before,
.pdf-modal.is-maximized .pdf-action-icon-maximize::after {
  content: "";
  position: absolute;
  border: 2px solid currentColor;
  border-radius: 3px;
  background: var(--color-canvas);
}

.pdf-modal.is-maximized .pdf-action-icon-maximize::before {
  width: 9px;
  height: 9px;
  right: -4px;
  top: -4px;
}

.pdf-modal.is-maximized .pdf-action-icon-maximize::after {
  width: 9px;
  height: 9px;
  left: -4px;
  bottom: -4px;
}

.pdf-modal-body {
  flex: 1 1 auto;
  min-height: 0;
  background: var(--color-surface-soft);
}

.pdf-modal-body iframe {
  width: 100%;
  height: 100%;
  display: block;
  border: 0;
  background: var(--color-canvas);
}

.web-info-grid {
  flex: 0 0 auto;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin: 28px 32px 0;
}

.web-info-panel {
  min-width: 0;
  padding: 22px 24px;
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-lg);
  background: rgba(255, 253, 248, 0.82);
  box-shadow: var(--shadow-soft);
  scroll-margin-top: 96px;
}

.web-info-kicker {
  display: inline-flex;
  align-items: center;
  min-height: 24px;
  padding: 0 9px;
  border-radius: 9px;
  background: var(--tint-cream);
  color: var(--color-stone);
  font-size: 12px;
  font-weight: 700;
}

.web-info-panel h2 {
  margin: 12px 0 0;
  color: var(--color-ink-deep);
  font-size: 18px;
  line-height: 1.35;
}

.web-info-panel p {
  margin: 9px 0 0;
  color: var(--color-slate);
  font-size: 14px;
  line-height: 1.7;
}

.site-footer {
  flex: 0 0 auto;
  min-height: 72px;
  margin: 24px 0 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  flex-wrap: wrap;
  color: var(--color-stone);
  font-size: 13px;
  border-top: 1px solid rgba(216, 207, 194, 0.58);
  background: rgba(250, 248, 244, 0.74);
}

.site-footer a {
  color: var(--color-slate);
}

.site-footer a:hover {
  color: var(--color-primary);
}

@media (max-width: 1500px) {
  .header-inner,
  .hero-banner,
  .filter-panel,
  .catalog-panel,
  .catalog-layout,
  .detail-shell {
    width: min(1180px, calc(100vw - 40px));
  }
}

@media (max-width: 1080px) {
  .login-modal {
    padding: 22px;
  }

  .login-modal-panel {
    width: min(760px, calc(100vw - 32px));
    min-height: auto;
    grid-template-columns: 1fr;
  }

  .login-brand-panel {
    min-height: 300px;
    padding: 38px 42px;
  }

  .login-brand-panel h2 {
    margin-top: 46px;
    font-size: 30px;
  }

  .login-accent {
    margin-bottom: 28px;
  }

  .login-points {
    gap: 16px;
    font-size: 20px;
  }

  .login-illustration {
    left: auto;
    width: 240px;
    right: 24px;
    opacity: 0.72;
  }

  .login-content-panel {
    padding: 38px 32px 34px;
  }

  .hero-banner,
  .catalog-layout,
  .detail-layout,
  .info-columns {
    grid-template-columns: 1fr;
  }

  .detail-sidebar {
    order: 2;
  }

  .detail-main {
    order: 1;
  }

  .catalog-sidebar {
    position: static;
    min-height: auto;
    max-height: none;
  }

  .catalog-main {
    max-height: none;
    overflow: visible;
  }

  .catalog-toolbar {
    position: static;
  }

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

  .web-info-grid {
    grid-template-columns: 1fr;
    margin-right: 20px;
    margin-left: 20px;
  }
}

@media (max-width: 760px) {
  .login-modal {
    align-items: stretch;
    padding: 12px;
  }

  .account-modal {
    align-items: stretch;
    padding: 12px;
  }

  .account-modal-panel {
    width: calc(100vw - 24px);
    max-height: calc(100vh - 24px);
    padding: 24px 18px;
    border-radius: 22px;
  }

  .account-bind-item,
  .account-bind-qr-head {
    align-items: stretch;
    flex-direction: column;
  }

  .account-bind-item button {
    width: 100%;
  }

  .account-bind-qr-box,
  .account-bind-qr-box iframe {
    width: min(238px, calc(100vw - 76px)) !important;
    height: min(238px, calc(100vw - 76px)) !important;
  }

  .login-modal-panel {
    width: calc(100vw - 24px);
    max-height: calc(100vh - 24px);
    overflow-y: auto;
    border-radius: 22px;
  }

  .login-modal-close {
    top: 12px;
    right: 12px;
  }

  .login-brand-panel {
    min-height: 230px;
    padding: 30px 28px;
  }

  .login-product-name {
    top: 38px;
    left: 96px;
    font-size: 22px;
  }

  .login-product-subtitle {
    top: 68px;
    left: 98px;
  }

  .login-brand-panel h2 {
    margin-top: 38px;
    font-size: 27px;
  }

  .login-points {
    gap: 12px;
    font-size: 17px;
  }

  .login-points li::before {
    width: 22px;
    height: 22px;
  }

  .login-illustration {
    display: none;
  }

  .login-content-panel h2 {
    font-size: 32px;
  }

  .login-form[data-login-panel="account"] {
    padding-top: 24px;
  }

  .login-method-label {
    margin-bottom: 22px;
    font-size: 18px;
  }

  .login-qr-box {
    width: min(320px, calc(100vw - 88px));
    height: min(320px, calc(100vw - 88px));
  }

  .login-qr-box iframe {
    width: min(320px, calc(100vw - 88px)) !important;
    height: min(320px, calc(100vw - 88px)) !important;
  }

  .login-qr-tip {
    margin: 22px 0 18px;
    font-size: 17px;
  }

  .header-inner,
  .hero-banner,
  .filter-panel,
  .catalog-panel,
  .catalog-layout,
  .detail-shell {
    width: min(100vw - 24px, 1180px);
  }

  .header-inner,
  .filter-row,
  .detail-topbar {
    align-items: stretch;
    flex-direction: column;
  }

  .header-links {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .hero-banner {
    gap: 18px;
    padding: 20px 0 16px;
  }

  .hero-copy h1 {
    font-size: 34px;
  }

  .hero-copy p {
    font-size: 16px;
  }

  .search-box {
    min-height: 56px;
  }

  .search-box input {
    font-size: 17px;
  }

  .filter-panel,
  .catalog-main,
  .detail-content-card,
  .book-card,
  .related-panel {
    padding-left: 18px;
    padding-right: 18px;
  }

  .grade-card {
    flex-basis: 150px;
    width: 150px;
    height: 179px;
  }

  .lesson-grid,
  .feature-list {
    grid-template-columns: 1fr;
  }

  .catalog-sidebar {
    border-radius: 22px;
    min-height: auto;
    border-right: 0;
    border-bottom: 1px solid var(--color-hairline);
  }

  .unit-list {
    display: flex;
    overflow-x: auto;
  }

  .unit-item {
    flex: 0 0 auto;
  }

  .lesson-grid {
    max-height: none;
    overflow: visible;
  }

  .detail-item {
    grid-template-columns: 82px minmax(0, 1fr);
  }

  .preview-stage {
    min-height: 280px;
  }

  .download-button {
    width: 100%;
  }

  .resource-file {
    flex: 0 0 300px;
    width: 300px;
    align-items: center;
    flex-direction: row;
  }

  .resource-pill {
    flex-basis: 260px;
    width: 260px;
  }

  .pdf-modal {
    padding: 10px;
  }

  .pdf-modal-panel {
    width: 100%;
    height: 94vh;
    border-radius: 18px;
  }

  .pdf-modal.is-maximized {
    padding: 0;
  }

  .pdf-modal.is-maximized .pdf-modal-panel {
    height: 100vh;
    border-radius: 0;
  }

  .pdf-modal-head {
    min-height: 54px;
    padding: 9px 10px 9px 12px;
    gap: 10px;
  }

  .pdf-modal-head h2 {
    max-width: calc(100vw - 210px);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-size: 15px;
  }

  .pdf-modal-actions {
    gap: 6px;
  }

  .pdf-modal-action {
    min-height: 32px;
    padding: 0 9px;
    font-size: 13px;
  }

  .pdf-action-text {
    display: none;
  }
}