/* MathStandard — academic editorial layout. Brand colours live in theme.css. */
:root {
  --editorial-serif:'Kanit',Tahoma,sans-serif;
}
.sr-only {
  position:absolute;
  width:1px;
  height:1px;
  padding:0;
  margin:-1px;
  overflow:hidden;
  clip:rect(0,0,0,0);
  white-space:nowrap;
  border:0;
}
.academic-header .header-inner {
  min-height:104px;
  padding-block:22px;
  gap:30px;
}
.academic-header .brand-lockup {
  width:243px;
}
.masthead-note {
  font:500 10px/1.8 'Kanit',sans-serif;
  letter-spacing:1.65px;
  margin-left:auto;
  color:var(--muted);
}
.masthead-links {
  display:flex;
  gap:24px;
  align-items:center;
  font-size:13px;
}
.masthead-links a {
  padding-block:12px;
}
.academic-header .main-nav {
  border-top:1px solid var(--line);
  display:flex;
  justify-content:space-between;
  gap:24px;
  padding-block:8px;
  width:min(1160px,calc(100% - 64px));
  margin-inline:auto;
  font-size:14px;
}
.academic-header .main-nav a {
  padding-block:7px;
  background:none;
  border-radius:0;
  min-height:44px;
}
.academic-header .main-nav a:last-child {
  margin-left:auto;
  color:var(--muted);
}
.academic-header a:hover {
  color:var(--blue);
}
.journal-home h1,.journal-home h2,.journal-home h3 {
  font-family:var(--editorial-serif);
  font-weight:500;
}
.journal-home .button {
  border-radius:2px;
  padding:14px 23px;
  font-size:14px;
}
.journal-kicker {
  font-size:12px;
  letter-spacing:.6px;
  font-weight:600;
  color:var(--blue);
  margin-bottom:24px;
}
.journal-kicker[lang=en] {
  font-size:10px;
  letter-spacing:1.7px;
}
.editorial-link {
  display:inline-block;
  font-size:14px;
  font-weight:500;
  color:var(--blue);
  text-decoration:underline;
  text-decoration-thickness:1px;
  text-underline-offset:6px;
  padding-block:10px;
}
.editorial-link:hover {
  text-decoration-thickness:2px;
}
.journal-hero {
  display:grid;
  grid-template-columns:1.15fr 1fr;
  gap:75px;
  align-items:center;
  padding-block:54px 62px;
}
.hero-editorial h1 {
  font-size:clamp(40px,4.2vw,56px);
  line-height:1.62;
  letter-spacing:-1.2px;
  font-weight:600;
}
.hero-editorial h1 span {
  color:var(--blue);
}
.hero-deck {
  font-size:17px;
  line-height:1.95;
  color:var(--muted);
  margin-top:22px;
  max-width:475px;
}
.hero-editorial .actions {
  gap:15px 24px;
  margin-top:28px;
}
.hero-availability {
  display:flex;
  gap:9px;
  align-items:baseline;
  color:var(--muted);
  font-size:12px;
  margin-top:17px;
}
.status-dot {
  width:6px;
  height:6px;
  flex:none;
  background:var(--blue);
  border-radius:50%;
}
.hero-colophon {
  display:flex;
  gap:28px;
  align-items:center;
  margin-top:40px;
  border-top:1px solid var(--line);
  padding-top:23px;
  max-width:460px;
}
.hero-colophon>span {
  font:500 11px/1.8 'Kanit',sans-serif;
  letter-spacing:1.1px;
  color:var(--blue);
  border-left:3px solid var(--lime);
  padding-left:13px;
}
.hero-colophon p {
  font-size:12px;
  line-height:1.8;
  color:var(--muted);
  margin:0;
}
.document-study {
  min-width:0;
  background:var(--pale);
  padding:18px 29px 20px;
  border-top:2px solid var(--blue);
}
.study-heading {
  display:flex;
  justify-content:space-between;
  gap:10px;
  font-size:10px;
  color:var(--muted);
  margin-bottom:17px;
}
.study-heading [lang=en] {
  letter-spacing:1.3px;
  font-size:9px;
}
.document-page {
  display:block;
  width:100%;
  max-width:307px;
  margin-inline:auto;
  background:white;
  box-shadow:0 5px 22px #13254c12;
  transition:box-shadow .2s;
}
.document-page:hover {
  box-shadow:0 5px 24px #13254c26;
}
.document-page img {
  width:100%;
  height:auto;
}
.document-study figcaption {
  border-top:1px solid #d2dcec;
  margin-top:20px;
  padding-top:16px;
  display:flex;
  justify-content:space-between;
  gap:15px;
  align-items:center;
}
.document-study figcaption strong {
  font-size:12px;
  font-weight:600;
  display:block;
}
.document-study figcaption div>span {
  font-size:10px;
  color:var(--muted);
  display:block;
  margin-top:4px;
}
.study-price {
  font:500 24px 'Kanit',sans-serif;
  color:var(--blue);
  white-space:nowrap;
}
.study-price small {
  font:400 10px 'Kanit',sans-serif;
  display:block;
  margin-top:5px;
  color:var(--muted);
}
.editorial-collections {
  border-top:1px solid var(--navy);
  padding-block:40px 74px;
}
.journal-section-heading {
  display:flex;
  justify-content:space-between;
  gap:24px;
  align-items:end;
  margin-bottom:33px;
}
.journal-section-heading .journal-kicker {
  margin-bottom:10px;
}
.journal-section-heading h2 {
  font-size:34px;
  line-height:1.6;
}
.collection-spread {
  display:grid;
  grid-template-columns:minmax(0,1.68fr) minmax(0,1fr);
  gap:57px;
}
.collection-main {
  min-width:0;
  padding-right:4px;
}
.collection-heading {
  display:flex;
  gap:22px;
  align-items:start;
}
.section-number {
  font:500 46px/1.2 'Kanit',sans-serif;
  color:var(--blue);
  padding-top:4px;
}
.overline {
  font-size:11px;
  color:var(--muted);
  letter-spacing:.4px;
  margin-bottom:8px;
}
.collection-heading h3 {
  font-size:28px;
  line-height:1.6;
}
.collection-intro {
  font-size:15px;
  line-height:1.9;
  color:var(--muted);
  margin-block:22px 25px;
  max-width:540px;
}
.exam-index {
  border-top:1px solid var(--navy);
  margin-bottom:18px;
}
.exam-index-row {
  display:grid;
  grid-template-columns:49px minmax(0,1fr) auto;
  gap:18px;
  align-items:center;
  padding-block:20px;
  border-bottom:1px solid var(--line);
}
.exam-index-number {
  font:500 18px 'Kanit',sans-serif;
  color:var(--muted);
}
.exam-index-row h4 {
  font-size:16px;
  font-weight:500;
  line-height:1.7;
}
.exam-index-row h4 a:hover {
  color:var(--blue);
  text-decoration:underline;
  text-underline-offset:4px;
}
.exam-index-row p {
  font-size:12px;
  color:var(--muted);
  margin-top:5px;
}
.exam-index-purchase {
  text-align:right;
}
.exam-index-purchase>span {
  font:500 22px 'Kanit',sans-serif;
  color:var(--navy);
  white-space:nowrap;
}
.exam-index-purchase small {
  font:400 11px 'Kanit',sans-serif;
}
.exam-index-purchase a {
  display:block;
  font-size:12px;
  color:var(--blue);
  padding-block:5px;
  text-decoration:underline;
  text-underline-offset:4px;
}
.collection-aside {
  border-left:1px solid var(--line);
  padding-left:38px;
}
.university-collection {
  padding-block:2px 29px;
  border-bottom:1px solid var(--line);
}
.collection-aside h3 {
  font-size:27px;
  line-height:1.65;
}
.collection-aside p:not(.overline) {
  font-size:14px;
  color:var(--muted);
  line-height:1.9;
  margin-top:15px;
}
.collection-aside .availability-note {
  font-size:11px!important;
  padding-left:10px;
  border-left:2px solid #bac6dd;
}
.summary-feature {
  padding-top:27px;
}
.summary-foot {
  display:flex;
  justify-content:space-between;
  gap:12px;
  align-items:center;
  margin-top:18px;
}
.summary-price {
  font:500 25px 'Kanit',sans-serif;
  white-space:nowrap;
}
.summary-price small {
  font:400 11px 'Kanit',sans-serif;
  color:var(--muted);
}
.sample-inline {
  font-size:12px;
  color:var(--blue);
  display:inline-block;
  padding-block:9px;
  text-decoration:underline;
  text-underline-offset:4px;
}
.academic-section {
  background:var(--navy);
  color:white;
  padding-block:67px;
}
.academic-layout {
  display:grid;
  grid-template-columns:1fr 1.18fr;
  gap:95px;
}
.academic-intro .journal-kicker {
  color:var(--lime);
}
.academic-intro h2 {
  font-size:35px;
  line-height:1.8;
}
.academic-intro>p:not(.journal-kicker) {
  font-size:14px;
  color:#d0d9eb;
  margin-block:22px 16px;
  line-height:1.9;
}
.academic-section .editorial-link {
  color:white;
}
.academic-notes {
  margin:0;
}
.academic-notes>div {
  padding-block:23px;
  border-top:1px solid #506080;
}
.academic-notes>div:first-child {
  padding-top:0;
  border-top:0;
}
.academic-notes>div:last-child {
  padding-bottom:0;
}
.academic-notes dt {
  font-size:18px;
  font-weight:500;
  display:flex;
  gap:20px;
}
.academic-notes dt span {
  font:500 13px/2.4 'Kanit',sans-serif;
  color:var(--lime);
  flex:none;
}
.academic-notes dd {
  margin:12px 0 0 39px;
  font-size:14px;
  line-height:1.95;
  color:#d0d9eb;
}
.practice-editorial {
  display:grid;
  grid-template-columns:.9fr 1.1fr;
  gap:110px;
  padding-block:77px;
}
.practice-heading h2 {
  font:500 clamp(44px,5.2vw,66px)/1.32 'Kanit',sans-serif;
  letter-spacing:-1.7px;
}
.practice-heading h2 em {
  font-style:normal;
  color:var(--blue);
  text-decoration:underline;
  text-decoration-color:var(--lime);
  text-decoration-thickness:5px;
  text-underline-offset:10px;
}
.practice-prose {
  padding-top:35px;
}
.practice-prose .practice-lead {
  font-family:var(--editorial-serif);
  font-size:25px;
  line-height:1.9;
  color:var(--navy);
}
.practice-prose>p:not(.practice-lead) {
  font-size:15px;
  line-height:2;
  color:var(--muted);
  margin-top:18px;
}
.teaching-note {
  border-top:1px solid var(--line);
  margin-top:28px;
  padding-top:24px;
}
.teaching-note h3 {
  font-size:20px;
}
.teaching-note p {
  font-size:14px;
  color:var(--muted);
  line-height:1.95;
  margin-top:13px;
}
.closing-strip {
  background:var(--pale);
  border-top:1px solid var(--line);
  padding-block:35px;
}
.closing-strip .wrap {
  display:flex;
  justify-content:space-between;
  gap:28px;
  align-items:center;
}
.closing-strip .journal-kicker {
  margin-bottom:8px;
}
.closing-strip h2 {
  font-size:24px;
  line-height:1.8;
}
.level-empty {
  display:grid;
  grid-template-columns:1.2fr 1fr;
  gap:60px;
  align-items:start;
  border-block:1px solid var(--line);
  padding-block:40px;
  margin-bottom:50px;
}
.level-empty h2 {
  font-family:var(--editorial-serif);
  font-size:30px;
  margin-bottom:17px;
}
.level-empty p {
  color:var(--muted);
}
.level-empty .level-index {
  border-left:1px solid var(--line);
  padding-left:30px;
}
.level-index .text-link {
  display:block;
  padding-block:10px;
}
@media(min-width:761px) and (max-width:1050px) {
  .masthead-note {
    display:none;
  }
  .journal-hero {
    gap:35px;
  }
  .hero-editorial h1 {
    font-size:43px;
  }
  .hero-deck {
    font-size:16px;
  }
  .document-study {
    padding-inline:20px;
  }
  .collection-spread {
    gap:30px;
  }
  .collection-aside {
    padding-left:27px;
  }
  .academic-layout {
    gap:50px;
  }
  .practice-editorial {
    gap:65px;
  }
}
@media(max-width:760px) {
  .academic-header .header-inner {
    min-height:88px;
    padding-block:18px;
    flex-wrap:wrap;
    gap:16px;
  }
  .academic-header .brand-lockup {
    width:211px;
  }
  .masthead-note,.masthead-links {
    display:none;
  }
  .academic-header .nav-toggle {
    margin-left:auto;
  }
  .academic-header .main-nav {
    display:grid;
    grid-template-columns:1fr 1fr;
    gap:0 18px;
    width:calc(100% - 40px);
    padding-block:7px 13px;
  }
  .academic-header .main-nav a {
    font-size:13px;
    padding:10px 0;
    border-bottom:1px solid var(--line);
    min-height:46px;
  }
  .academic-header .main-nav a:last-child {
    margin:0;
  }
  .journal-hero {
    grid-template-columns:1fr;
    gap:34px;
    padding-block:32px 38px;
  }
  .journal-kicker {
    font-size:11px;
    margin-bottom:17px;
  }
  .hero-editorial h1 {
    font-size:clamp(31px,8.1vw,48px);
    line-height:1.65;
    letter-spacing:-.65px;
  }
  .hero-deck {
    font-size:15px;
    line-height:1.95;
    margin-top:17px;
    max-width:490px;
  }
  .desktop-break {
    display:none;
  }
  .hero-editorial .actions {
    margin-top:23px;
    gap:12px 18px;
    align-items:center;
  }
  .journal-home .button {
    font-size:13px;
    padding-inline:16px;
  }
  .hero-availability {
    font-size:11px;
    margin-top:14px;
    line-height:1.9;
  }
  .hero-colophon {
    margin-top:23px;
    padding-top:17px;
    gap:24px;
  }
  .hero-colophon>span {
    font-size:9px;
  }
  .hero-colophon p {
    font-size:11px;
  }
  .document-study {
    padding:17px 22px 20px;
    max-width:490px;
    width:100%;
    justify-self:center;
  }
  .document-page {
    max-width:270px;
  }
  .study-heading {
    font-size:9px;
  }
  .study-heading [lang=en] {
    font-size:8px;
    letter-spacing:1px;
  }
  .document-study figcaption {
    margin-top:18px;
    padding-top:15px;
  }
  .document-study figcaption strong {
    font-size:11px;
  }
  .study-price {
    font-size:23px;
  }
  .editorial-collections {
    padding-block:30px 40px;
  }
  .journal-section-heading {
    align-items:start;
    gap:14px;
    margin-bottom:29px;
  }
  .journal-section-heading h2 {
    font-size:27px;
  }
  .journal-section-heading .editorial-link {
    font-size:12px;
    margin-top:30px;
    white-space:nowrap;
  }
  .collection-spread {
    grid-template-columns:1fr;
    gap:35px;
  }
  .collection-heading {
    gap:18px;
  }
  .section-number {
    font-size:39px;
  }
  .collection-heading h3 {
    font-size:25px;
  }
  .collection-intro {
    font-size:14px;
    margin-block:18px 22px;
  }
  .exam-index-row {
    grid-template-columns:26px minmax(0,1fr) auto;
    gap:10px;
    padding-block:19px;
  }
  .exam-index-row h4 {
    font-size:14px;
  }
  .exam-index-row p {
    font-size:11px;
  }
  .exam-index-purchase>span {
    font-size:20px;
  }
  .exam-index-purchase a {
    font-size:11px;
    min-height:40px;
    display:flex;
    align-items:center;
    justify-content:end;
  }
  .exam-index-number {
    font-size:15px;
  }
  .collection-aside {
    border-left:0;
    border-top:1px solid var(--navy);
    padding:28px 0 0;
    display:grid;
    grid-template-columns:1fr;
    gap:25px;
  }
  .university-collection {
    padding:0 0 25px;
  }
  .collection-aside h3 {
    font-size:25px;
  }
  .summary-feature {
    padding-top:0;
  }
  .summary-foot {
    justify-content:start;
    gap:26px;
  }
  .summary-foot .editorial-link {
    margin-left:auto;
  }
  .sample-inline {
    min-height:44px;
    display:inline-flex;
    align-items:center;
  }
  .academic-section {
    padding-block:40px;
  }
  .academic-layout {
    grid-template-columns:1fr;
    gap:32px;
  }
  .academic-intro h2 {
    font-size:30px;
    line-height:1.75;
  }
  .academic-intro h2 br {
    display:none;
  }
  .academic-intro>p:not(.journal-kicker) {
    margin-block:18px 12px;
  }
  .academic-notes dt {
    font-size:16px;
    gap:16px;
  }
  .academic-notes dd {
    margin-left:34px;
    font-size:14px;
  }
  .practice-editorial {
    grid-template-columns:1fr;
    gap:25px;
    padding-block:42px;
  }
  .practice-heading h2 {
    font-size:49px;
    line-height:1.32;
  }
  .practice-heading .journal-kicker {
    margin-bottom:20px;
  }
  .practice-prose {
    padding:0;
  }
  .practice-prose .practice-lead {
    font-size:24px;
    line-height:1.8;
  }
  .practice-prose>p:not(.practice-lead) {
    font-size:14px;
  }
  .teaching-note h3 {
    font-size:21px;
  }
  .closing-strip {
    padding-block:29px;
  }
  .closing-strip .wrap {
    display:block;
  }
  .closing-strip h2 {
    font-size:24px;
  }
  .closing-strip .button {
    margin-top:20px;
    width:100%;
  }
  .level-empty {
    grid-template-columns:1fr;
    gap:27px;
    padding-block:26px;
  }
  .level-empty .level-index {
    border-left:0;
    border-top:1px solid var(--line);
    padding:22px 0 0;
  }
}
@media(max-width:360px) {
  .academic-header .brand-lockup {
    width:192px;
  }
  .academic-header .main-nav {
    width:calc(100% - 32px);
  }
  .hero-editorial .actions {
    display:grid;
    grid-template-columns:1fr;
  }
  .hero-editorial .actions .editorial-link {
    text-align:center;
  }
  .document-study {
    padding-inline:15px;
  }
  .study-heading [lang=en] {
    letter-spacing:.6px;
  }
  .hero-colophon {
    gap:16px;
  }
  .journal-section-heading {
    display:block;
  }
  .journal-section-heading .editorial-link {
    margin-top:8px;
  }
}
@media(prefers-reduced-motion:reduce) {
  .document-page {
    transition:none;
  }
}
@media print {
  .masthead-links,.academic-header .main-nav {
    display:none;
  }
  .journal-hero,.collection-spread,.academic-layout,.practice-editorial {
    display:block;
  }
  .academic-section {
    background:white;
    color:var(--navy);
  }
  .document-study {
    max-width:350px;
    break-inside:avoid;
  }
}
/* Utility links move into the expanded menu on narrow screens. */
.academic-header .main-nav .nav-utility {
  display:none;
}
@media(max-width:760px) {
  .academic-header .main-nav .nav-utility {
    display:flex;
  }
  .js .academic-header .main-nav:not(.is-open) {
    display:none;
  }
  .academic-header .main-nav a:last-child {
    margin:0;
  }
}

/* Free learning edition and the brand's educational Facebook channel. */
.hero-free-context { font-size:14px; line-height:1.85; color:var(--muted); max-width:450px; margin-top:10px; }
.collection-status { font-size:13px; line-height:1.9; color:var(--muted); margin:20px 0; }
.exam-index-row.is-free { background:#f4f7ff; padding-inline:12px; border-left:3px solid var(--blue); }
.free-label { color:var(--blue); }
.exam-index-purchase .free-label small { display:block; line-height:1.6; }
.free-product { border-top:3px solid var(--blue); }
.product-availability { font-size:13px; color:var(--muted); margin:8px 0 15px; }
.free-panel { border-left:3px solid var(--blue); background:#f4f7ff; }
.free-panel .badge { background:var(--lime); color:var(--navy); }
.free-sample .small { margin-top:18px; }
.facebook-editorial { display:grid; grid-template-columns:minmax(0,1fr) minmax(0,1.1fr); gap:72px; padding-block:62px; border-top:1px solid var(--line); }
.facebook-editorial h2 { font-family:'Kanit',sans-serif; font-weight:500; line-height:1.5; font-size:clamp(25px,3vw,36px); }
.facebook-editorial p { line-height:1.9; }
.facebook-editorial .button { margin:22px 0 12px; }
.contact-facebook { margin-top:40px; padding-bottom:0; }
@media(max-width:760px) {
  .facebook-editorial { grid-template-columns:1fr; gap:20px; padding-block:36px; }
  .facebook-editorial h2 br { display:none; }
  .hero-free-context { margin-top:12px; }
  .exam-index-purchase .free-label small { font-size:11px; }
}
@media(max-width:420px) {
  .exam-index-row.is-free { padding-inline:8px; }
}

/* Knowledge-sharing home: an open reading collection before the paid catalogue. */
.sharing-home .journal-hero { gap:64px; }
.sharing-home .hero-editorial h1 { font-size:clamp(36px,4vw,52px); }
.sharing-intent { max-width:475px; font-size:15px; line-height:1.95; color:var(--muted); margin-top:22px; }
.sharing-home .hero-colophon { margin-top:28px; }
.open-library { padding-block:50px 64px; border-top:1px solid var(--line); }
.section-deck { max-width:820px; font-size:16px; line-height:1.95; color:var(--muted); margin:0 0 32px; }
.open-resource-spread { display:grid; grid-template-columns:1.15fr 1fr; border-top:2px solid var(--blue); }
.open-resource { padding:32px 34px 34px 0; min-width:0; display:flex; flex-direction:column; align-items:flex-start; }
.open-resource-exam { padding-left:34px; padding-right:0; border-left:1px solid var(--line); }
.resource-overline { display:flex; justify-content:space-between; align-items:center; gap:18px; width:100%; margin-bottom:24px; font-size:12px; color:var(--muted); }
.open-label { color:var(--blue); font-weight:600; border-bottom:3px solid var(--lime); white-space:nowrap; }
.open-resource h3 { font-family:'Kanit',sans-serif; font-size:clamp(23px,2.3vw,29px); line-height:1.6; font-weight:500; margin-bottom:17px; }
.open-resource>p { color:var(--muted); font-size:15px; line-height:1.95; }
.open-resource-facts { display:flex; gap:32px; margin:24px 0 18px; padding:0; }
.open-resource-facts dt { color:var(--blue); font:500 32px/1.4 'Kanit',sans-serif; }
.open-resource-facts dd { font-size:12px; color:var(--muted); margin:4px 0 0; }
.open-resource .resource-detail { font-size:12px; margin-bottom:24px; }
.open-resource .actions { margin-top:auto; gap:16px; }
.open-use-note { border-top:1px solid var(--line); padding-top:24px; display:grid; grid-template-columns:1fr auto; gap:32px; align-items:center; }
.open-use-note p { color:var(--muted); font-size:14px; line-height:1.9; }
.open-use-note strong { color:var(--navy); }
.open-use-note .editorial-link { font-size:13px; }
.paid-collection-band { background:#f7f9fd; padding-block:58px; border-block:1px solid var(--line); }
.paid-collection-band .journal-section-heading { margin-bottom:30px; }
.paid-collection-band .collection-main { padding-top:0; }
.lesson-direction { min-width:0; padding-left:34px; border-left:1px solid var(--line); }
.lesson-direction h3 { font-family:'Kanit',sans-serif; font-size:29px; font-weight:500; line-height:1.6; margin:12px 0 22px; }
.lesson-direction p { color:var(--muted); font-size:15px; line-height:1.95; }
.lesson-direction .editorial-link { margin-top:28px; }
.catalog-access-group { margin-top:36px; }
.catalog-access-group .section-head { margin-bottom:24px; }
.catalog-access-group h2 { font-size:25px; }
.catalog-access-note { font-size:14px; color:var(--muted); margin:0 0 25px; }
.free-doc-links { margin:22px 0 0; padding:0; list-style:none; }
.free-doc-links li { border-top:1px solid var(--line); padding:17px 0; }
.free-doc-links .text-link { display:inline-block; margin-bottom:8px; }
@media(max-width:1050px) {
 .sharing-home .journal-hero { gap:34px; }
 .open-resource .actions { flex-direction:column; align-items:flex-start; }
}
@media(max-width:760px) {
 .sharing-home .journal-hero { gap:36px; }
 .sharing-home .hero-editorial h1 { font-size:clamp(31px,7.6vw,43px); }
 .sharing-intent { font-size:14px; }
 .open-library { padding-block:34px 40px; }
 .open-resource-spread { grid-template-columns:1fr; }
 .open-resource { padding:28px 0 32px; }
 .open-resource-exam { border-left:0; border-top:1px solid var(--line); }
 .resource-overline { margin-bottom:20px; }
 .open-resource h3 { font-size:25px; }
 .open-resource .actions { width:100%; flex-direction:row; align-items:center; }
 .open-use-note { grid-template-columns:1fr; gap:12px; }
 .paid-collection-band { padding-block:38px; }
 .paid-collection-band .availability-note { display:block; margin-top:16px; }
 .lesson-direction { border-left:0; border-top:1px solid var(--line); padding:30px 0 0; margin-top:12px; }
 .lesson-direction h3 { font-size:26px; }
}
@media(max-width:360px) {
 .open-resource h3 { font-size:23px; }
 .open-resource .actions { flex-direction:column; align-items:flex-start; }
}
.lesson-index { margin:52px 0 64px; }
.lesson-index-heading { display:grid; grid-template-columns:1fr auto; gap:40px; border-top:2px solid var(--navy); padding:32px 0; }
.lesson-index-heading h2 { font:500 clamp(25px,3vw,36px)/1.6 var(--editorial-serif); margin:8px 0 15px; }
.lesson-index-heading p:not(.eyebrow):not(.lesson-index-price) { color:var(--muted); max-width:650px; }
.lesson-index-price { font:500 38px/1.5 'Kanit',sans-serif; text-align:right; color:var(--blue); }
.lesson-index-price span { font:400 14px/1.8 'Kanit',sans-serif; }
.lesson-index-price small { display:block; font:400 12px/1.8 'Kanit',sans-serif; color:var(--muted); }
.lesson-jumps { display:flex; flex-wrap:wrap; gap:12px 30px; border-block:1px solid var(--line); padding:18px 0; }
.lesson-jumps a { font-size:15px; padding-block:8px; }
.lesson-jumps span { color:var(--muted); font-size:12px; margin-left:10px; }
.lesson-search { margin:26px 0 40px; max-width:650px; }
.lesson-search label { display:block; font-size:14px; margin-bottom:10px; }
.lesson-search input { width:100%; border:1px solid #aebbd2; padding:14px 16px; border-radius:3px; background:white; color:var(--navy); font:inherit; min-height:48px; }
.lesson-search p { margin-top:9px; }
.lesson-subject { scroll-margin-top:30px; margin-top:42px; }
.lesson-subject>header { display:flex; align-items:baseline; justify-content:space-between; gap:24px; padding-bottom:19px; border-bottom:1px solid var(--navy); }
.lesson-subject h3 { font:500 26px/1.7 var(--editorial-serif); }
.lesson-subject>header .eyebrow { order:2; max-width:50%; }
.lesson-row { display:grid; grid-template-columns:148px minmax(0,1fr) 220px; gap:28px; padding:30px 0; border-bottom:1px solid var(--line); align-items:center; }
.lesson-row-image { display:block; width:148px; }
.lesson-row-image img { display:block; width:100%; height:auto; border:1px solid var(--line); }
.lesson-row h4 { font:500 23px/1.65 var(--editorial-serif); margin:6px 0 10px; }
.lesson-row-copy>p:not(.product-meta) { font-size:14px; color:var(--muted); line-height:1.9; }
.lesson-row-facts { margin-top:10px; }
.lesson-row-actions { display:flex; flex-direction:column; gap:14px; align-items:flex-start; }
.lesson-price { font:500 28px/1.5 'Kanit',sans-serif; color:var(--blue); }
.lesson-price small { font:400 12px/1.8 'Kanit',sans-serif; color:var(--muted); }
.lesson-row-actions .button { font-size:13px; padding:12px 14px; min-height:44px; width:100%; }
.lesson-row-actions .text-link { font-size:13px; padding-block:8px; }
.lesson-no-results { padding:35px 0; color:var(--muted); }
.lesson-home-price { font:500 38px/1.5 'Kanit',sans-serif; color:var(--blue); margin-block:18px; }
.lesson-home-price small { font:400 14px/1.8 'Kanit',sans-serif; }
.lesson-detail .detail-intro h1 { font-family:var(--editorial-serif); font-weight:500; }
.lesson-overview { border-top:1px solid var(--line); }
.lesson-topic-list li { break-inside:avoid; }
.lesson-related { display:flex; flex-direction:column; border-top:1px solid var(--line); }
.lesson-related a { display:flex; justify-content:space-between; gap:20px; padding:20px 0; border-bottom:1px solid var(--line); }
.lesson-related span { color:var(--muted); font-size:13px; }
@media(max-width:1000px) {
 .lesson-row { grid-template-columns:120px minmax(0,1fr); gap:22px; }
 .lesson-row-image { width:120px; }
 .lesson-row-actions { grid-column:2; flex-direction:row; flex-wrap:wrap; align-items:center; gap:12px 20px; }
 .lesson-row-actions .button { width:auto; }
 .lesson-subject>header { display:block; }
 .lesson-subject>header .eyebrow { max-width:none; }
}
@media(max-width:600px) {
 .lesson-index-heading { grid-template-columns:1fr; gap:18px; padding:25px 0; }
 .lesson-index-price { text-align:left; font-size:32px; }
 .lesson-jumps { display:grid; gap:4px; }
 .lesson-jumps a { display:flex; justify-content:space-between; }
 .lesson-row { grid-template-columns:76px minmax(0,1fr); gap:14px; padding:25px 0; align-items:start; }
 .lesson-row-image { width:76px; }
 .lesson-row h4 { font-size:20px; }
 .lesson-row-actions { grid-column:1/-1; width:100%; gap:12px; }
 .lesson-row-actions .button { margin-left:auto; }
 .lesson-row-actions .text-link { width:100%; }
 .lesson-price { font-size:25px; }
 .lesson-row-facts { font-size:12px!important; }
 .lesson-related a { flex-direction:column; gap:5px; }
}

/* Opening announcement follows the existing academic masthead. */
[hidden]{display:none!important}
.launch-announcement{background:#13254c;color:white;border-bottom:3px solid #d4f37b}
.launch-announcement>.wrap>span{display:flex;align-items:center;justify-content:space-between;gap:24px;padding:17px 0;font-size:.95rem;line-height:1.65}
.launch-announcement strong{font-weight:600;margin-right:12px;color:#d4f37b}
.launch-announcement time{display:inline}
.launch-announcement a{flex-shrink:0;color:white;text-decoration:underline;text-underline-offset:5px}
.launch-order{margin-top:18px}
@media(max-width:700px){.launch-announcement>.wrap>span{display:block;padding:14px 0;font-size:.86rem}.launch-announcement strong{display:block}.launch-announcement a{display:inline-block;margin-top:7px}.launch-announcement time{display:block}}

/* Shared knowledge: junior mathematics learning map. */
.map-home{display:grid;grid-template-columns: .8fr 1.3fr;gap:48px;align-items:center;padding-top:70px;padding-bottom:70px;border-top:1px solid #ccd5e5}.map-home img{display:block;width:100%;height:auto;border:1px solid #ccd5e5}.map-home p{max-width:42ch}.learning-map .page-head{max-width:850px}.learning-map .page-head h1{line-height:1.3}.map-full{padding-bottom:48px}.map-tools{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin:20px 0}.map-tools button{font:inherit;cursor:pointer}.map-viewport{border:1px solid #ccd5e5;overflow:auto;max-height:760px;background:white}.map-viewport a{display:block}.map-viewport img{display:block;width:100%;max-width:none;height:auto}.map-viewport.is-enlarged a{width:200%;min-width:1800px}.map-reading{display:grid;grid-template-columns:1fr 1.4fr;gap:48px;padding:44px 0;border-top:1px solid #ccd5e5;border-bottom:1px solid #ccd5e5}.map-reading ol{margin:0;padding-left:24px}.map-reading li{padding:0 0 20px 10px}.map-reading strong{display:block}.map-jumps{display:flex;gap:12px;flex-wrap:wrap;padding:30px 0}.map-jumps a{border-bottom:1px solid #ccd5e5;padding:12px 16px 12px 0}.map-jumps span{color:#163cab;margin-right:14px}.map-chapter{display:grid;grid-template-columns:.65fr 1.6fr;gap:40px;padding:46px 0;border-top:1px solid #ccd5e5;scroll-margin-top:180px}.map-chapter header h2{line-height:1.45}.map-detail-images{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:26px}.map-detail-images figure{margin:0}.map-detail-images img{display:block;width:100%;height:auto;border:1px solid #e6eaf2}.map-detail-images figcaption{margin-top:12px}.map-detail-images h3{font-size:20px;line-height:1.6;margin-bottom:5px}.map-detail-images p{font-size:15px;color:#54627b;line-height:1.8}.map-use{padding:40px;background:#f3f6fc;margin:35px 0 60px}.map-use p{max-width:75ch}
@media(max-width:760px){.map-home,.map-reading,.map-chapter{grid-template-columns:1fr;gap:24px}.map-home{padding-top:40px;padding-bottom:40px}.learning-map .page-head h1{font-size:clamp(30px,8vw,44px)}.map-full .journal-section-heading{align-items:flex-start;gap:16px}.map-viewport{max-height:520px}.map-detail-images{grid-template-columns:1fr}.map-detail-images figure{max-width:520px}.map-use{padding:24px}.map-chapter{scroll-margin-top:110px}.map-tools .small{width:100%}.map-jumps{display:grid;gap:0}.map-reading{padding:30px 0}}
/* Public two-page review library: editorial rows and generous reading space. */
.review-intro{display:grid;grid-template-columns:1fr 1.18fr;gap:6%;align-items:center;padding-block:70px;border-top:1px solid var(--line,#ccd5e5)}
.review-intro h2{margin:12px 0 20px}.review-intro-art img,.review-detail-banner img{width:100%;height:auto;display:block}.review-intro-art{background:#f3f6fc}
.review-jumps{display:flex;gap:0;flex-wrap:wrap;border-block:1px solid #ccd5e5;margin:0 0 60px}.review-jumps a{padding:18px 24px 18px 0;margin-right:30px;color:#13254c;text-decoration:none;font-weight:600}.review-jumps span{display:block;font-size:.8rem;font-weight:400;color:#54627b;margin-top:5px}
.review-group{display:grid;grid-template-columns:230px 1fr;gap:40px;margin-bottom:70px;scroll-margin-top:30px}.review-group h2{font-size:1.65rem}.review-row{display:grid;grid-template-columns:132px 1fr;gap:22px;align-items:start;border-top:1px solid #ccd5e5;padding:24px 0}.review-thumb img{width:100%;display:block;height:auto}.review-row h3{font-size:1.35rem;margin:8px 0}.review-row h3 a{color:inherit;text-decoration:none}.review-row-text p{margin:6px 0}.review-row-actions{grid-column:2;display:flex;gap:18px;align-items:center;flex-wrap:wrap;margin-top:-8px}.review-row-actions .button{padding:10px 15px;font-size:.87rem}.review-library a:focus-visible,.review-detail a:focus-visible{outline:3px solid #163cab;outline-offset:4px}
.review-use{padding:35px 0 50px;border-top:1px solid #ccd5e5;max-width:850px}.review-detail-banner{margin:0 0 60px;max-width:1050px}.review-pages{margin-bottom:45px}.review-page-spread{display:grid;grid-template-columns:1fr 1fr;gap:24px}.review-page-spread figure{margin:0}.review-page-spread img{display:block;width:100%;height:auto;border:1px solid #ccd5e5}.review-page-spread figcaption{font-size:.85rem;color:#54627b;margin:12px 0}.review-adjacent{display:flex;justify-content:space-between;gap:25px;margin:0 0 70px}.review-adjacent a{color:#13254c;text-decoration:none}.review-adjacent span{display:block;color:#54627b;font-size:.8rem;margin-bottom:8px}
@media(max-width:850px){.review-group{grid-template-columns:1fr;gap:20px}.review-group>header{max-width:none}.review-intro{gap:30px;grid-template-columns:1fr;padding-block:45px}.review-detail-banner{margin-bottom:35px}}
@media(max-width:560px){.review-row{grid-template-columns:88px minmax(0,1fr);gap:14px}.review-row h3{font-size:1.14rem;overflow-wrap:anywhere}.review-row-actions{grid-column:1/-1;margin-top:0}.review-row-text p{font-size:.88rem}.review-jumps{display:grid;grid-template-columns:1fr;gap:0;margin-bottom:35px}.review-jumps a{padding:12px 0;margin:0;border-bottom:1px solid #ccd5e5}.review-jumps a:last-child{border:0}.review-jumps span{display:inline;margin-left:12px}.review-page-spread{grid-template-columns:1fr}.review-pages .journal-section-heading{align-items:start;gap:12px;flex-direction:column}.review-detail .page-head h1{font-size:2.3rem}.review-adjacent{flex-direction:column}}
/* Unified library navigation and accessible topic search. */
.library-search{background:#f3f6fc;padding:28px;margin:24px 0 0;border-top:3px solid #163cab}.library-search label{display:block;font-size:.9rem;font-weight:600;margin-bottom:9px}.library-query-row{display:flex;gap:12px}.library-search input,.library-search select{font:inherit;color:#13254c;background:#fff;border:1px solid #aebbd3;border-radius:3px;min-height:48px;padding:10px 14px;max-width:100%}.library-search input{flex:1;min-width:0}.library-filters{display:flex;gap:24px;margin-top:20px}.library-filters>div{flex:1}.library-search select{width:100%}.library-toolbar{display:flex;justify-content:space-between;gap:20px;align-items:center;margin:24px 0}.library-toolbar p{margin:0}.library-row{display:grid;grid-template-columns:128px minmax(0,1fr);gap:28px;padding:27px 0;border-top:1px solid #ccd5e5}.library-row-art img{display:block;width:100%;height:128px;object-fit:contain;background:#f3f6fc}.library-row h2{font-size:1.55rem;line-height:1.6;margin:7px 0}.library-row h2 a{color:#13254c;text-decoration:none}.library-row-copy>p{margin:6px 0}.library-kind{color:#54627b;font-size:.84rem}.library-badge{display:inline-block;border:1px solid #b7c5de;padding:4px 10px;font-size:.85rem;margin-top:10px}.library-badge.is-free{color:#163cab;background:#eff3ff;border-color:#ccd9ff}.library-opening{font-size:.8rem;color:#54627b;margin-left:12px}.library-row-actions{display:flex;gap:22px;align-items:center;margin-top:18px;flex-wrap:wrap}.library-row-actions .button{padding:10px 15px;font-size:.87rem}.library-empty{padding:40px;background:#f3f6fc}.library-shortcuts{display:flex;flex-wrap:wrap;gap:0;border-block:1px solid #ccd5e5;margin:30px 0}.library-shortcuts a{padding:18px 24px 18px 0;margin-right:26px;font-weight:600;color:#13254c;text-decoration:none}.library-shortcuts span{display:block;color:#54627b;font-size:.8rem;font-weight:400;margin-top:5px}.quick-search{margin:20px 0 0;display:flex;gap:10px;max-width:620px}.quick-search input{min-width:0;flex:1;border:1px solid #aebbd3;border-radius:3px;padding:12px;font:inherit}.quick-search .button{white-space:nowrap}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.reading-paths{display:flex;flex-wrap:wrap;gap:10px 25px;margin:25px 0 0}.reading-paths a{color:#163cab;text-decoration:underline;text-underline-offset:4px;font-size:.85rem}.review-library-search{padding:20px 0;border-bottom:1px solid #ccd5e5;margin-bottom:24px}.review-library-search label{display:block;font-size:.9rem;margin-bottom:9px;font-weight:600}.review-library-search input{width:100%;max-width:600px;padding:12px;font:inherit;border:1px solid #aebbd3}.review-library-search p{font-size:.85rem;color:#54627b;margin:12px 0}
.library-row[hidden],.library-empty[hidden],.review-row[hidden],.review-group[hidden]{display:none!important}
@media(max-width:700px){.library-search{padding:18px}.library-filters{flex-direction:column;gap:15px}.library-toolbar{align-items:start;flex-direction:column;gap:8px}.library-shortcuts{display:grid;grid-template-columns:1fr}.library-shortcuts a{margin:0;padding:14px 0;border-bottom:1px solid #ccd5e5}.library-shortcuts a:last-child{border:0}.library-row{grid-template-columns:88px minmax(0,1fr);gap:16px}.library-row-art img{height:88px}.library-row h2{font-size:1.17rem}.library-row-copy>p{font-size:.87rem}.library-row-actions{gap:14px}.library-opening{display:block;margin:8px 0}.library-query-row{flex-wrap:wrap}.library-query-row input{flex-basis:100%}.quick-search .button{padding-inline:15px}}

.library-page>.page-head{padding-top:32px;padding-bottom:0;margin-bottom:28px}.library-page>.page-head .lead{margin-bottom:0}.library-page .library-search{margin-top:0}
/* Exam references and original practice sets share the established editorial grid. */
.exam-series-nav{display:flex;flex-wrap:wrap;gap:12px;margin:24px 0 36px}.exam-series-nav a{flex:1 1 240px;border-top:2px solid #ccd5e5;padding:16px 12px;color:#13254c;text-decoration:none}.exam-series-nav a[aria-current=page]{border-color:#163cab;background:#f3f6fc}.exam-series-nav strong,.exam-series-nav span{display:block}.exam-series-nav span{font-size:.86rem;color:#54627b;margin-top:6px}.free-exam-list{display:grid;grid-template-columns:1fr 1fr;gap:30px;margin:28px 0 44px}.free-exam-list article{display:grid;grid-template-columns:130px 1fr;gap:22px;padding:24px 0;border-top:1px solid #ccd5e5;min-width:0}.free-exam-cover img{width:100%;height:auto;display:block}.free-exam-list h3{font-size:1.12rem;line-height:1.6;margin:4px 0 10px}.free-exam-list h3 a{color:#13254c;text-decoration:none}.free-exam-list p{font-size:.88rem}.free-exam-list .button{font-size:.84rem;padding:11px 15px}.free-exam-list .actions{gap:12px}.exam-download-all{display:flex;justify-content:space-between;gap:24px;align-items:center;background:#f3f6fc;padding:24px 30px}.home-free-exam-index{margin-top:32px}.home-free-exam-index .free-exam-list{margin-bottom:0}.free-exam-list .journal-kicker{font-size:.73rem}.exam-index{max-height:580px;overflow:auto;scrollbar-gutter:stable}.exam-index-row{padding-right:10px}
@media(max-width:720px){.free-exam-list{grid-template-columns:1fr;gap:4px}.free-exam-list article{grid-template-columns:100px 1fr;gap:16px}.free-exam-list .actions{align-items:flex-start;flex-direction:column}.exam-download-all{align-items:flex-start;flex-direction:column;padding:22px}.exam-series-nav{gap:0}.exam-series-nav a{flex-basis:100%;padding:14px 10px}.exam-index{max-height:650px}.free-exam-list h3{font-size:1.04rem}}

/* Kanit: retain Thai spacing and readable body copy at narrow widths. */
h1,h2,h3,h4,.journal-kicker { letter-spacing:0; }
.hero-editorial h1 { font-weight:500; letter-spacing:0; line-height:1.5; }
.sharing-intent,.section-deck,.detail-body p,.reading-grid p,.review-use p,
.map-reading li,.practice-prose>p:not(.practice-lead) { font-size:16px; line-height:1.9; }
@media(max-width:760px) {
  .hero-editorial h1 { letter-spacing:0; }
  .hero-deck { font-size:16px; }
  .journal-kicker { font-size:12px; letter-spacing:0; }
  .academic-notes dd { font-size:15px; }
  .journal-home .button { font-size:14px; }
}