/*
Theme Name: Toancap1
Theme URI: https://toancap1.com
Author: Toancap1.com
Author URI: https://toancap1.com
Description: Theme WordPress thuan cho website Toan cap 1, Toan tieu hoc lop 1-5 va on thi vao lop 6, kem cong thuc toan va tai tai lieu co dem nguoc.
Version: 1.0.38
Requires at least: 6.0
Tested up to: 6.6
Requires PHP: 7.4
Text Domain: toancap1
*/

:root {
  --tc-primary: #2563eb;
  --tc-primary-dark: #1d4ed8;
  --tc-secondary: #f97316;
  --tc-accent: #facc15;
  --tc-green: #16a34a;
  --tc-purple: #7c3aed;
  --tc-pink: #db2777;
  --tc-ink: #0f172a;
  --tc-text: #334155;
  --tc-muted: #64748b;
  --tc-soft: #f8fafc;
  --tc-soft-blue: #eff6ff;
  --tc-border: #e2e8f0;
  --tc-white: #ffffff;
  --tc-shadow: 0 14px 34px rgba(15, 23, 42, 0.09);
  --tc-shadow-soft: 0 8px 22px rgba(15, 23, 42, 0.07);
  --tc-radius: 8px;
  --tc-container: 1120px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--tc-soft);
  color: var(--tc-text);
  font-family: Nunito, "Segoe UI", Roboto, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body.admin-bar .site-header {
  top: 32px;
}

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

a:hover {
  color: var(--tc-primary);
}

img {
  display: block;
  height: auto;
  max-width: 100%;
}

button,
input,
textarea,
select {
  font: inherit;
}

.screen-reader-text {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.tc-container {
  width: min(var(--tc-container), calc(100% - 32px));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid rgba(226, 232, 240, 0.88);
  box-shadow: 0 4px 16px rgba(15, 23, 42, 0.04);
  backdrop-filter: blur(14px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 78px;
  gap: 24px;
}

.site-branding {
  flex: 0 0 auto;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--tc-primary);
}

.custom-logo-link img {
  width: auto;
  max-height: 56px;
}

.brand-icon {
  display: grid;
  width: 44px;
  height: 44px;
  place-items: center;
  border-radius: var(--tc-radius);
  background: #fff7ed;
  font-size: 28px;
  line-height: 1;
}

.brand-name {
  color: var(--tc-primary);
  font-size: 26px;
  font-weight: 900;
  letter-spacing: 0;
  line-height: 1;
}

.brand-name span {
  color: var(--tc-secondary);
}

.primary-nav {
  flex: 1 1 auto;
}

.primary-menu,
.primary-nav ul {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 26px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.primary-menu li,
.primary-nav li {
  position: relative;
}

.primary-menu a,
.primary-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  color: #475569;
  font-weight: 800;
  transition: color 160ms ease;
}

.primary-menu a:hover,
.primary-menu .current-menu-item > a,
.primary-menu .current-menu-ancestor > a {
  color: var(--tc-primary);
}

.primary-menu .menu-item-has-children > a::after,
.primary-menu .has-dropdown > a::after {
  content: "";
  width: 7px;
  height: 7px;
  margin-left: 8px;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg) translateY(-2px);
}

.primary-menu .sub-menu,
.primary-menu .dropdown-menu {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  display: block;
  width: 220px;
  padding: 8px;
  background: var(--tc-white);
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  box-shadow: var(--tc-shadow);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity 180ms ease, transform 180ms ease, visibility 180ms ease;
}

.primary-menu li:hover > .sub-menu,
.primary-menu li:focus-within > .sub-menu,
.primary-menu li:hover > .dropdown-menu,
.primary-menu li:focus-within > .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.primary-menu .sub-menu a,
.primary-menu .dropdown-menu a {
  display: block;
  min-height: 0;
  padding: 10px 12px;
  border-radius: 6px;
  font-size: 14px;
}

.primary-menu .sub-menu a:hover,
.primary-menu .dropdown-menu a:hover {
  background: var(--tc-soft-blue);
}

.header-actions {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
}

.icon-button {
  display: inline-grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: #64748b;
  cursor: pointer;
  transition: background 160ms ease, color 160ms ease, transform 160ms ease;
}

.icon-button:hover,
.icon-button:focus-visible {
  background: var(--tc-soft-blue);
  color: var(--tc-primary);
}

.cta-pill,
.tc-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 46px;
  padding: 0 22px;
  border: 2px solid transparent;
  border-radius: 999px;
  background: var(--tc-primary);
  color: var(--tc-white);
  font-weight: 900;
  box-shadow: var(--tc-shadow-soft);
  transition: transform 160ms ease, background 160ms ease, box-shadow 160ms ease, border-color 160ms ease, color 160ms ease;
}

.cta-pill {
  background: var(--tc-secondary);
}

.cta-pill:hover,
.tc-button:hover {
  color: var(--tc-white);
  transform: translateY(-2px);
  box-shadow: var(--tc-shadow);
}

.cta-pill:hover {
  background: #ea580c;
}

.tc-button:hover {
  background: var(--tc-primary-dark);
}

.tc-button.is-secondary {
  background: var(--tc-white);
  border-color: var(--tc-border);
  color: var(--tc-text);
}

.tc-button.is-secondary:hover {
  border-color: var(--tc-secondary);
  color: var(--tc-secondary);
}

.site-search {
  position: absolute;
  top: calc(100% + 14px);
  right: 0;
  display: flex;
  width: min(360px, calc(100vw - 32px));
  padding: 10px;
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  box-shadow: var(--tc-shadow);
}

.site-search[hidden] {
  display: none;
}

.site-search input {
  flex: 1 1 auto;
  min-width: 0;
  border: 0;
  outline: 0;
  padding: 10px 12px;
  color: var(--tc-ink);
}

.site-search button {
  border: 0;
  border-radius: 999px;
  background: var(--tc-primary);
  color: var(--tc-white);
  font-weight: 800;
  padding: 0 16px;
  cursor: pointer;
}

.site-search-form {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

.site-search-form input[type="search"] {
  flex: 1 1 240px;
  min-height: 46px;
  min-width: 0;
  padding: 0 14px;
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  color: var(--tc-ink);
}

.mobile-menu-toggle {
  display: none;
  flex: 0 0 auto;
}

.mobile-menu-icon {
  position: relative;
  display: block;
  width: 22px;
  height: 18px;
}

.mobile-menu-icon span {
  position: absolute;
  left: 0;
  width: 22px;
  height: 2px;
  border-radius: 999px;
  background: currentColor;
  transition: top 180ms ease, transform 180ms ease, opacity 140ms ease;
}

.mobile-menu-icon span:nth-child(1) {
  top: 1px;
}

.mobile-menu-icon span:nth-child(2) {
  top: 8px;
}

.mobile-menu-icon span:nth-child(3) {
  top: 15px;
}

.mobile-menu-toggle[aria-expanded="true"] .mobile-menu-icon span:nth-child(1) {
  top: 8px;
  transform: rotate(45deg);
}

.mobile-menu-toggle[aria-expanded="true"] .mobile-menu-icon span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle[aria-expanded="true"] .mobile-menu-icon span:nth-child(3) {
  top: 8px;
  transform: rotate(-45deg);
}

.hero {
  position: relative;
  overflow: hidden;
  background:
    linear-gradient(180deg, rgba(239, 246, 255, 0.84), rgba(255, 255, 255, 0.94)),
    repeating-linear-gradient(0deg, rgba(37, 99, 235, 0.055) 0, rgba(37, 99, 235, 0.055) 1px, transparent 1px, transparent 36px),
    repeating-linear-gradient(90deg, rgba(249, 115, 22, 0.045) 0, rgba(249, 115, 22, 0.045) 1px, transparent 1px, transparent 36px);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(360px, 0.95fr);
  align-items: center;
  gap: 48px;
  padding: 64px 0 76px;
}

.hero-copy {
  max-width: 620px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 20px;
  padding: 8px 14px;
  border: 1px solid #bfdbfe;
  border-radius: 999px;
  background: var(--tc-soft-blue);
  color: var(--tc-primary);
  font-size: 14px;
  font-weight: 900;
}

.hero h1 {
  margin: 0;
  color: var(--tc-ink);
  font-size: 58px;
  line-height: 1.07;
  font-weight: 900;
  letter-spacing: 0;
}

.hero h1 .blue {
  color: var(--tc-primary);
}

.hero h1 .orange {
  color: var(--tc-secondary);
}

.hero-text {
  margin: 22px 0 0;
  color: #475569;
  font-size: 20px;
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 30px;
}

.hero-art {
  position: relative;
  border: 4px solid var(--tc-white);
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  box-shadow: 0 26px 52px rgba(15, 23, 42, 0.18);
  overflow: hidden;
  transform: rotate(1.5deg);
  transition: transform 220ms ease;
}

.hero-art:hover {
  transform: rotate(0deg);
}

.hero-art img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.math-chip {
  position: absolute;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 14px;
  border-radius: var(--tc-radius);
  background: rgba(255, 255, 255, 0.9);
  color: var(--tc-primary);
  font-size: 21px;
  font-weight: 900;
  box-shadow: var(--tc-shadow-soft);
  animation: tc-float 3.4s ease-in-out infinite;
}

.math-chip.one {
  top: 18px;
  left: 18px;
}

.math-chip.two {
  right: 22px;
  bottom: 24px;
  color: var(--tc-secondary);
  animation-delay: 0.6s;
}

.math-chip.three {
  right: 30px;
  top: 86px;
  color: var(--tc-green);
  animation-delay: 1.1s;
}

@keyframes tc-float {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-8px);
  }
}

.section {
  padding: 72px 0;
}

.section.is-white {
  background: var(--tc-white);
}

.section-heading {
  max-width: 760px;
  margin: 0 auto 40px;
  text-align: center;
}

.section-heading h2 {
  margin: 0;
  color: var(--tc-ink);
  font-size: 36px;
  line-height: 1.18;
  font-weight: 900;
  letter-spacing: 0;
}

.section-heading p {
  margin: 14px 0 0;
  color: var(--tc-muted);
  font-size: 18px;
}

.grade-grid,
.post-grid,
.formula-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
}

.resource-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 20px;
}

.grade-card,
.post-card,
.resource-card,
.formula-card,
.download-box,
.not-found-box {
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  box-shadow: var(--tc-shadow-soft);
}

.grade-card {
  display: block;
  min-height: 230px;
  padding: 28px;
  border-bottom: 5px solid transparent;
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}

.grade-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--tc-shadow);
}

.grade-card.grade-1:hover {
  border-bottom-color: var(--tc-primary);
}

.grade-card.grade-2:hover {
  border-bottom-color: var(--tc-green);
}

.grade-card.grade-3:hover {
  border-bottom-color: var(--tc-purple);
}

.grade-card.grade-4:hover {
  border-bottom-color: var(--tc-pink);
}

.grade-card.grade-5:hover {
  border-bottom-color: var(--tc-secondary);
}

.grade-card.grade-6 {
  background: #fef3c7;
}

.grade-card.grade-6:hover {
  border-bottom-color: #d97706;
}

.grade-icon,
.resource-icon,
.post-icon {
  display: grid;
  width: 62px;
  height: 62px;
  margin-bottom: 20px;
  place-items: center;
  border-radius: var(--tc-radius);
  background: var(--tc-soft-blue);
  font-size: 30px;
  transition: transform 180ms ease;
}

.grade-card:hover .grade-icon,
.resource-card:hover .resource-icon {
  transform: scale(1.06);
}

.grade-card h3 {
  margin: 0 0 8px;
  color: var(--tc-ink);
  font-size: 24px;
  line-height: 1.2;
  font-weight: 900;
}

.grade-card p {
  margin: 0;
  color: var(--tc-muted);
  font-weight: 700;
}

.exam-section {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 12px 12px, rgba(255, 255, 255, 0.16) 2px, transparent 3px),
    linear-gradient(135deg, #2563eb, #1d4ed8 62%, #1e40af);
  background-size: 28px 28px, auto;
  color: var(--tc-white);
}

.exam-header {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 34px;
}

.exam-header h2 {
  max-width: 720px;
  margin: 12px 0;
  font-size: 44px;
  line-height: 1.14;
  font-weight: 900;
}

.exam-header p {
  max-width: 720px;
  margin: 0;
  font-size: 18px;
}

.badge-white {
  display: inline-flex;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--tc-white);
  color: var(--tc-primary);
  font-size: 13px;
  font-weight: 900;
  text-transform: uppercase;
}

.exam-section .post-card {
  color: var(--tc-text);
}

.post-card {
  display: flex;
  flex-direction: column;
  min-height: 260px;
  padding: 22px;
  overflow: hidden;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.post-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--tc-shadow);
}

.post-card .post-thumb {
  margin: -22px -22px 18px;
  background: #dbeafe;
}

.post-card .post-thumb img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
  color: #94a3b8;
  font-size: 13px;
  font-weight: 800;
}

.post-views {
  color: #64748b;
}

.post-label {
  display: inline-flex;
  padding: 4px 8px;
  border-radius: 999px;
  background: #dbeafe;
  color: #1d4ed8;
  font-size: 12px;
  font-weight: 900;
  text-transform: uppercase;
}

.post-card h3,
.post-card h2 {
  margin: 0 0 10px;
  color: var(--tc-ink);
  font-size: 20px;
  line-height: 1.32;
  font-weight: 900;
}

.post-card p {
  margin: 0 0 20px;
  color: var(--tc-muted);
}

.post-card .read-more {
  margin-top: auto;
  display: inline-flex;
  justify-content: center;
  width: 100%;
  min-height: 44px;
  align-items: center;
  border-radius: var(--tc-radius);
  background: #f1f5f9;
  color: var(--tc-primary);
  font-weight: 900;
  transition: background 160ms ease, color 160ms ease;
}

.post-card .read-more:hover {
  background: var(--tc-primary);
  color: var(--tc-white);
}

.formula-section {
  background:
    linear-gradient(180deg, #fff7ed, #ffffff);
}

.formula-card {
  padding: 24px;
}

.formula-card h3 {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 12px;
  color: var(--tc-ink);
  font-size: 20px;
  line-height: 1.25;
  font-weight: 900;
}

.formula-expression,
.tc-formula-expression {
  display: block;
  margin: 14px 0;
  padding: 16px;
  border-radius: var(--tc-radius);
  background: #0f172a;
  color: #fefce8;
  font-size: 24px;
  font-weight: 900;
  line-height: 1.35;
  overflow-x: auto;
}

.formula-card p {
  margin: 0;
  color: var(--tc-muted);
}

.resource-card {
  display: block;
  padding: 16px;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.resource-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--tc-shadow);
}

.resource-visual {
  display: grid;
  min-height: 150px;
  margin-bottom: 14px;
  place-items: center;
  border-radius: var(--tc-radius);
  background: #f1f5f9;
  font-size: 38px;
}

.resource-card h3 {
  margin: 0;
  color: var(--tc-ink);
  font-size: 16px;
  line-height: 1.38;
  font-weight: 900;
}

.site-footer {
  background: #0f172a;
  color: #cbd5e1;
  padding: 64px 0 28px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr repeat(3, minmax(0, 1fr));
  gap: 44px;
  margin-bottom: 40px;
}

.footer-brand .brand-name {
  color: var(--tc-white);
}

.footer-brand p {
  margin: 18px 0 0;
  color: #94a3b8;
  font-size: 14px;
}

.footer-col h3 {
  margin: 0 0 16px;
  color: var(--tc-white);
  font-size: 14px;
  font-weight: 900;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

.footer-col ul {
  display: grid;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 14px;
}

.footer-col a {
  color: #cbd5e1;
}

.footer-col a:hover {
  color: var(--tc-white);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding-top: 24px;
  border-top: 1px solid #1e293b;
  color: #94a3b8;
  font-size: 14px;
}

.footer-policy {
  display: flex;
  gap: 18px;
}

.page-header {
  padding: 48px 0;
  background: var(--tc-white);
  border-bottom: 1px solid var(--tc-border);
}

.page-header h1 {
  margin: 0;
  color: var(--tc-ink);
  font-size: 42px;
  line-height: 1.16;
  font-weight: 900;
}

.page-header p {
  max-width: 760px;
  margin: 14px 0 0;
  color: var(--tc-muted);
  font-size: 18px;
}

.content-wrap {
  padding: 52px 0 72px;
}

.single-layout {
  display: grid;
  grid-template-columns: minmax(0, 760px) minmax(260px, 1fr);
  gap: 42px;
  align-items: start;
}

.single-main {
  min-width: 0;
}

.site-sidebar {
  min-width: 0;
}

.single-article,
.page-article {
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  box-shadow: var(--tc-shadow-soft);
  overflow: hidden;
}

.article-inner {
  padding: 36px;
}

.single-title {
  margin: 0 0 16px;
  color: var(--tc-ink);
  font-size: 42px;
  line-height: 1.16;
  font-weight: 900;
}

.single-thumb img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.entry-content {
  color: #1f2937;
  font-size: 18px;
}

.entry-content > *:first-child {
  margin-top: 0;
}

.entry-content h2,
.entry-content h3,
.entry-content h4 {
  color: var(--tc-ink);
  line-height: 1.25;
  font-weight: 900;
}

.entry-content h2 {
  margin-top: 34px;
  font-size: 30px;
}

.entry-content h3 {
  margin-top: 28px;
  font-size: 24px;
}

.entry-content a {
  color: var(--tc-primary);
  font-weight: 800;
}

.entry-content ul,
.entry-content ol {
  padding-left: 24px;
}

.entry-content blockquote {
  margin: 24px 0;
  padding: 18px 22px;
  border-left: 5px solid var(--tc-primary);
  border-radius: var(--tc-radius);
  background: var(--tc-soft-blue);
  color: #1e3a8a;
  font-weight: 700;
}

.entry-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  overflow: hidden;
  border-radius: var(--tc-radius);
}

.entry-content th,
.entry-content td {
  padding: 12px 14px;
  border: 1px solid var(--tc-border);
  text-align: left;
}

.entry-content th {
  background: #f1f5f9;
  color: var(--tc-ink);
}

.tc-formula {
  margin: 24px 0;
  padding: 20px;
  border: 1px solid #fed7aa;
  border-radius: var(--tc-radius);
  background: #fff7ed;
}

.tc-formula figcaption {
  margin-bottom: 10px;
  color: #9a3412;
  font-size: 15px;
  font-weight: 900;
}

.tc-math-inline {
  display: inline-flex;
  align-items: baseline;
  padding: 2px 7px;
  border-radius: 6px;
  background: #eff6ff;
  color: #1d4ed8;
  font-weight: 900;
}

.download-box {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 18px;
  margin: 30px 0;
  padding: 22px;
  border-color: #bfdbfe;
  background: linear-gradient(135deg, #eff6ff, #ffffff);
}

.download-icon {
  display: grid;
  width: 56px;
  height: 56px;
  place-items: center;
  border-radius: var(--tc-radius);
  background: var(--tc-primary);
  color: var(--tc-white);
  font-size: 28px;
  font-weight: 900;
}

.download-title {
  display: block;
  color: var(--tc-ink);
  font-size: 21px;
  font-weight: 900;
}

.download-description {
  margin: 4px 0 16px;
  color: var(--tc-muted);
}

.download-button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  border: 0;
  border-radius: 999px;
  background: var(--tc-secondary);
  color: var(--tc-white);
  padding: 0 22px;
  font-weight: 900;
  cursor: pointer;
  transition: background 160ms ease, transform 160ms ease;
}

.download-button:hover,
.download-button:focus-visible {
  background: #ea580c;
  transform: translateY(-1px);
}

.download-button[disabled] {
  cursor: wait;
  opacity: 0.78;
  transform: none;
}

.download-status {
  margin-top: 12px;
  color: #1d4ed8;
  font-weight: 800;
}

.download-result {
  margin-top: 14px;
}

.download-result a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  border-radius: 999px;
  background: var(--tc-green);
  color: var(--tc-white);
  font-weight: 900;
}

.download-error {
  color: #b91c1c;
}

.sidebar-card {
  margin-bottom: 20px;
  padding: 22px;
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  box-shadow: var(--tc-shadow-soft);
}

.sidebar-card h2,
.sidebar-card h3 {
  margin: 0 0 14px;
  color: var(--tc-ink);
  font-size: 18px;
  font-weight: 900;
}

.sidebar-card ul {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.post-navigation,
.pagination {
  margin-top: 32px;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 14px;
}

.nav-links a,
.page-numbers {
  display: inline-flex;
  min-height: 42px;
  align-items: center;
  padding: 0 14px;
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  color: var(--tc-primary);
  font-weight: 800;
}

.page-numbers.current {
  background: var(--tc-primary);
  color: var(--tc-white);
}

.not-found-box {
  padding: 36px;
}

.comment-area-wrap {
  margin-top: 28px;
}

.tc-contact-form {
  margin-top: 26px;
  padding: 24px;
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  background: #f8fafc;
}

.tc-contact-form p {
  margin: 0 0 16px;
}

.tc-form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.tc-contact-form label {
  display: block;
  margin-bottom: 7px;
  color: var(--tc-ink);
  font-size: 15px;
  font-weight: 900;
}

.tc-contact-form label span {
  color: #dc2626;
}

.tc-contact-form input,
.tc-contact-form textarea {
  width: 100%;
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  color: var(--tc-ink);
  padding: 12px 14px;
}

.tc-contact-form input:focus,
.tc-contact-form textarea:focus {
  outline: 3px solid rgba(37, 99, 235, 0.16);
  border-color: var(--tc-primary);
}

.tc-form-message {
  margin-bottom: 18px;
  padding: 12px 14px;
  border-radius: var(--tc-radius);
  font-weight: 800;
}

.tc-form-message.is-success {
  background: #dcfce7;
  color: #166534;
}

.tc-form-message.is-error {
  background: #fee2e2;
  color: #991b1b;
}

.tc-contact-hidden {
  position: absolute;
  left: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

@media (max-width: 1020px) {
  .hero-grid,
  .single-layout {
    grid-template-columns: 1fr;
  }

  .hero-copy {
    max-width: 760px;
  }

  .hero h1 {
    font-size: 46px;
  }

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

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

@media (max-width: 820px) {
  body.admin-bar .site-header {
    top: 46px;
  }

  .header-inner {
    min-height: 68px;
  }

  .primary-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    max-height: calc(100vh - 68px);
    max-height: calc(100dvh - 68px);
    overflow-y: auto;
    overscroll-behavior: contain;
    padding: 14px 16px 18px;
    border-bottom: 1px solid var(--tc-border);
    background: var(--tc-white);
    box-shadow: var(--tc-shadow);
    -webkit-overflow-scrolling: touch;
  }

  .primary-nav.is-open {
    display: block;
  }

  .primary-menu,
  .primary-nav ul {
    display: grid;
    justify-content: stretch;
    gap: 4px;
  }

  .primary-menu a,
  .primary-nav a {
    display: flex;
    min-height: 44px;
    padding: 0 10px;
    border-radius: 6px;
  }

  .primary-menu > li > a:hover,
  .primary-menu > li > a:focus-visible,
  .primary-menu > .current-menu-item > a,
  .primary-menu > .current-menu-ancestor > a {
    background: var(--tc-soft-blue);
  }

  .primary-menu .sub-menu,
  .primary-menu .dropdown-menu {
    position: static;
    width: auto;
    margin: 0 0 8px 12px;
    border: 0;
    box-shadow: none;
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .header-actions .cta-pill {
    display: none;
  }

  .mobile-menu-toggle {
    display: inline-grid;
  }

  body.mobile-menu-open {
    overflow: hidden;
  }

  .custom-logo-link img {
    max-height: 48px;
  }

  .brand-name {
    font-size: 23px;
  }

  .hero-grid {
    padding: 42px 0 56px;
  }

  .hero h1 {
    font-size: 38px;
  }

  .hero-text {
    font-size: 18px;
  }

  .grade-grid,
  .post-grid,
  .formula-grid {
    grid-template-columns: 1fr;
  }

  .exam-header {
    display: block;
  }

  .exam-header h2 {
    font-size: 36px;
  }

  .exam-header .tc-button {
    margin-top: 24px;
  }

  .single-title,
  .page-header h1 {
    font-size: 34px;
  }
}

@media (max-width: 600px) {
  .tc-container {
    width: min(var(--tc-container), calc(100% - 24px));
  }

  .brand-icon {
    width: 38px;
    height: 38px;
    font-size: 23px;
  }

  .brand-name {
    font-size: 21px;
  }

  .section {
    padding: 52px 0;
  }

  .section-heading h2 {
    font-size: 30px;
  }

  .button-row,
  .footer-bottom,
  .nav-links {
    flex-direction: column;
    align-items: stretch;
  }

  .tc-button,
  .cta-pill {
    width: 100%;
  }

  .hero-art {
    transform: none;
  }

  .math-chip {
    font-size: 16px;
    min-height: 36px;
  }

  .resource-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .tc-form-grid {
    grid-template-columns: 1fr;
  }

  .article-inner {
    padding: 24px 18px;
  }

  .entry-content {
    font-size: 17px;
  }

  .download-box {
    grid-template-columns: 1fr;
  }

  .download-icon {
    width: 48px;
    height: 48px;
  }
}

.archive-page,
.single-page {
  padding: 32px 0 72px;
}

.tc-breadcrumbs {
  margin-bottom: 24px;
  color: #64748b;
  font-size: 14px;
  font-weight: 800;
}

.tc-breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.tc-breadcrumbs li {
  display: inline-flex;
  align-items: center;
  min-width: 0;
}

.tc-breadcrumbs li + li::before {
  content: "›";
  margin-right: 8px;
  color: #94a3b8;
  font-size: 18px;
  line-height: 1;
}

.tc-breadcrumbs a {
  color: #64748b;
}

.tc-breadcrumbs a:hover,
.tc-breadcrumbs span {
  color: var(--tc-primary);
}

.archive-hero {
  position: relative;
  min-height: 210px;
  margin-bottom: 40px;
  padding: 42px;
  border-radius: var(--tc-radius);
  overflow: hidden;
  color: var(--tc-white);
  box-shadow: var(--tc-shadow);
}

.archive-hero.is-blue {
  background: linear-gradient(135deg, #60a5fa, #2563eb);
}

.archive-hero.is-green {
  background: linear-gradient(135deg, #4ade80, #16a34a);
}

.archive-hero.is-purple {
  background: linear-gradient(135deg, #a78bfa, #7c3aed);
}

.archive-hero.is-pink {
  background: linear-gradient(135deg, #f472b6, #db2777);
}

.archive-hero.is-orange {
  background: linear-gradient(135deg, #fb923c, #ea580c);
}

.archive-hero.is-yellow {
  background: linear-gradient(135deg, #facc15, #f59e0b);
  color: #422006;
}

.archive-hero-copy {
  position: relative;
  z-index: 2;
  max-width: 760px;
}

.archive-hero h1 {
  margin: 0 0 14px;
  font-size: 48px;
  line-height: 1.12;
  font-weight: 900;
  letter-spacing: 0;
}

.archive-hero h1 span {
  display: inline-block;
  margin-left: 8px;
}

.archive-hero p {
  margin: 0;
  max-width: 720px;
  color: rgba(255, 255, 255, 0.9);
  font-size: 20px;
  font-weight: 700;
}

.archive-hero.is-yellow p {
  color: rgba(66, 32, 6, 0.76);
}

.archive-hero-decor {
  position: absolute;
  z-index: 1;
  font-weight: 900;
  line-height: 1;
  opacity: 0.2;
  pointer-events: none;
}

.archive-hero-decor.one {
  right: -18px;
  bottom: -38px;
  font-size: 128px;
  transform: rotate(-12deg);
}

.archive-hero-decor.two {
  top: 36px;
  right: 132px;
  font-size: 58px;
  animation: tc-float 2.8s ease-in-out infinite;
}

.archive-layout,
.single-view-layout {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(280px, 1fr);
  gap: 40px;
  align-items: start;
}

.archive-layout.no-sidebar,
.single-view-layout.no-sidebar {
  grid-template-columns: 1fr;
}

.archive-layout.no-sidebar .archive-main,
.single-view-layout.no-sidebar .single-main {
  width: 100%;
  max-width: 920px;
  margin-inline: auto;
}

.archive-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 28px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--tc-border);
}

.archive-toolbar h2 {
  margin: 0;
  color: var(--tc-ink);
  font-size: 26px;
  line-height: 1.2;
  font-weight: 900;
}

.archive-toolbar h2::before {
  content: "📚";
  margin-right: 8px;
}

.archive-sort {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #475569;
  font-size: 14px;
  font-weight: 800;
}

.archive-sort select {
  min-height: 40px;
  border: 1px solid #cbd5e1;
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  color: var(--tc-text);
  padding: 0 12px;
  font-weight: 800;
}

.archive-post-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.lesson-card {
  display: block;
  min-height: 0;
  padding: 0;
  border-color: #f1f5f9;
  border-radius: var(--tc-radius);
  overflow: hidden;
}

.lesson-card-visual {
  position: relative;
  display: grid;
  height: 200px;
  place-items: center;
  background:
    radial-gradient(circle at 20% 20%, rgba(255, 255, 255, 0.9), transparent 28%),
    linear-gradient(135deg, #eff6ff, #dbeafe);
  color: var(--tc-primary);
  overflow: hidden;
}

.lesson-card:nth-child(2n) .lesson-card-visual {
  background: linear-gradient(135deg, #faf5ff, #ede9fe);
  color: var(--tc-purple);
}

.lesson-card:nth-child(3n) .lesson-card-visual {
  background: linear-gradient(135deg, #fefce8, #fef3c7);
  color: #b45309;
}

.lesson-card-visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 240ms ease;
}

.lesson-card:hover .lesson-card-visual img,
.lesson-card:hover .lesson-placeholder-art {
  transform: scale(1.06);
}

.lesson-placeholder-art {
  position: relative;
  display: block;
  width: 118px;
  height: 118px;
  transition: transform 240ms ease;
}

.lesson-placeholder-art span {
  position: absolute;
  display: block;
  border-radius: 999px;
  background: currentColor;
  opacity: 0.82;
}

.lesson-placeholder-art span:nth-child(1) {
  width: 74px;
  height: 74px;
  left: 8px;
  top: 8px;
}

.lesson-placeholder-art span:nth-child(2) {
  width: 52px;
  height: 52px;
  right: 6px;
  bottom: 10px;
  border-radius: 14px;
  opacity: 0.56;
}

.lesson-placeholder-art span:nth-child(3) {
  width: 42px;
  height: 42px;
  right: 18px;
  top: 12px;
  border-radius: 0;
  clip-path: polygon(50% 0, 100% 100%, 0 100%);
  opacity: 0.7;
}

.bookmark-label {
  position: absolute;
  top: 16px;
  left: 0;
  z-index: 2;
  display: inline-flex;
  min-height: 28px;
  align-items: center;
  padding: 0 12px;
  background: var(--tc-primary);
  color: var(--tc-white);
  box-shadow: 2px 2px 5px rgba(15, 23, 42, 0.16);
  font-size: 12px;
  font-weight: 900;
  text-transform: uppercase;
}

.bookmark-label::after {
  content: "";
  position: absolute;
  top: 100%;
  left: 0;
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 7px 7px 0 0;
  border-color: #1e40af transparent transparent transparent;
}

.lesson-hover-play {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  background: rgba(15, 23, 42, 0.12);
  color: var(--tc-white);
  font-size: 28px;
  opacity: 0;
  transition: opacity 180ms ease;
}

.lesson-card:hover .lesson-hover-play {
  opacity: 1;
}

.lesson-card-body {
  padding: 24px;
}

.lesson-card h3 {
  display: -webkit-box;
  min-height: 52px;
  margin-bottom: 12px;
  overflow: hidden;
  color: var(--tc-ink);
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 2;
}

.lesson-card p {
  display: -webkit-box;
  min-height: 46px;
  overflow: hidden;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 2;
}

.lesson-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--tc-primary);
  font-weight: 900;
}

.archive-pagination {
  margin: 38px 0 8px;
}

.archive-pagination .nav-links,
.comments-pagination .nav-links {
  justify-content: center;
}

.site-sidebar {
  display: grid;
  gap: 24px;
}

.site-sidebar .sidebar-card {
  margin: 0;
  border-color: #f1f5f9;
  border-radius: var(--tc-radius);
}

.site-sidebar .widget-title {
  display: flex;
  align-items: center;
  gap: 10px;
}

.site-sidebar .widget-title::before {
  content: "";
  width: 8px;
  height: 26px;
  border-radius: 999px;
  background: var(--tc-primary);
}

.sidebar-title {
  display: flex;
  align-items: center;
  gap: 10px;
}

.sidebar-title::before {
  content: "";
  width: 8px;
  height: 26px;
  border-radius: 999px;
  background: var(--tc-primary);
}

.sidebar-title.has-secondary::before {
  background: var(--tc-secondary);
}

.sidebar-title.has-accent::before {
  background: var(--tc-accent);
}

.grade-sidebar-list {
  display: grid;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.grade-sidebar-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 48px;
  padding: 8px 12px;
  border: 1px solid transparent;
  border-radius: var(--tc-radius);
  color: #475569;
  font-weight: 900;
}

.grade-sidebar-list a:hover {
  background: var(--tc-soft-blue);
}

.grade-sidebar-list a.is-active {
  border-color: #bbf7d0;
  background: #f0fdf4;
  color: #15803d;
}

.grade-sidebar-list em {
  display: inline-flex;
  min-width: 28px;
  justify-content: center;
  border-radius: 999px;
  background: #f1f5f9;
  color: #64748b;
  font-size: 12px;
  font-style: normal;
  line-height: 24px;
}

.sidebar-post-list {
  display: grid;
  gap: 16px;
}

.sidebar-post-item {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
}

.sidebar-post-icon,
.sidebar-post-rank {
  display: grid;
  width: 64px;
  height: 64px;
  place-items: center;
  border-radius: var(--tc-radius);
  background: #eff6ff;
  color: var(--tc-primary);
  font-size: 15px;
  font-weight: 900;
  text-align: center;
}

.sidebar-post-rank {
  background: #fff7ed;
  color: var(--tc-secondary);
  font-size: 20px;
}

.sidebar-post-icon span {
  display: block;
  width: 30px;
  height: 30px;
  border-radius: 8px;
  background: currentColor;
  opacity: 0.75;
}

.sidebar-post-item strong {
  display: -webkit-box;
  overflow: hidden;
  color: #334155;
  font-size: 14px;
  line-height: 1.35;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 2;
}

.sidebar-post-item:hover strong {
  color: var(--tc-primary);
}

.sidebar-post-item em {
  display: block;
  margin-top: 4px;
  color: #94a3b8;
  font-size: 12px;
  font-style: normal;
  font-weight: 800;
}

.sidebar-teacher {
  text-align: center;
}

.site-sidebar .widget_toancap1_teacher_intro {
  text-align: center;
}

.teacher-avatar {
  display: grid;
  width: 92px;
  height: 92px;
  margin: 0 auto 16px;
  place-items: center;
  border-radius: 999px;
  background: linear-gradient(135deg, #dbeafe, #ede9fe);
  box-shadow: inset 0 0 18px rgba(37, 99, 235, 0.12);
  font-size: 46px;
}

.sidebar-teacher p {
  margin-bottom: 0;
  color: var(--tc-muted);
  font-size: 14px;
}

.sidebar-download-card {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--tc-primary), #1d4ed8);
  color: var(--tc-white);
}

.site-sidebar .widget_toancap1_download_box {
  position: relative;
  overflow: hidden;
  border-color: transparent;
  background: linear-gradient(135deg, var(--tc-primary), #1d4ed8);
  color: var(--tc-white);
}

.sidebar-download-inner {
  position: relative;
  z-index: 1;
}

.sidebar-download-inner h2,
.sidebar-download-inner p {
  color: inherit;
}

.sidebar-download-inner p {
  color: #dbeafe;
}

.sidebar-download-inner a {
  display: flex;
  min-height: 42px;
  align-items: center;
  justify-content: center;
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  color: var(--tc-primary);
  font-weight: 900;
}

.sidebar-download-inner > span {
  position: absolute;
  right: -14px;
  bottom: -34px;
  z-index: -1;
  font-size: 76px;
  opacity: 0.18;
  transform: rotate(-12deg);
}

.sidebar-download-card h2,
.sidebar-download-card p {
  position: relative;
  z-index: 1;
  color: inherit;
}

.sidebar-download-card p {
  color: #dbeafe;
}

.sidebar-download-card a,
.sidebar-challenge a {
  position: relative;
  z-index: 1;
  display: flex;
  min-height: 42px;
  align-items: center;
  justify-content: center;
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  color: var(--tc-primary);
  font-weight: 900;
}

.sidebar-download-card > span {
  position: absolute;
  right: -14px;
  bottom: -18px;
  font-size: 76px;
  opacity: 0.18;
  transform: rotate(-12deg);
}

.sidebar-challenge {
  border: 0;
  background: linear-gradient(135deg, #fde047, #f59e0b);
  color: #422006;
  text-align: center;
}

.challenge-icon {
  font-size: 48px;
  line-height: 1;
}

.sidebar-challenge h2 {
  color: #422006;
}

.sidebar-challenge p {
  color: #78350f;
  font-weight: 700;
}

.sidebar-challenge a {
  background: #111827;
  color: var(--tc-white);
}

.single-view-layout {
  grid-template-columns: minmax(0, 2fr) minmax(280px, 1fr);
}

.lesson-article,
.lesson-comments {
  border: 1px solid #f1f5f9;
  border-radius: var(--tc-radius);
  background: var(--tc-white);
  box-shadow: var(--tc-shadow-soft);
}

.lesson-article {
  padding: 15px 20px 20px 20px;
}

.lesson-header {
  margin-bottom: 0;
}

.lesson-header .single-title {
  margin-bottom: 18px;
}

.lesson-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 18px;
  margin-bottom: 24px;
  color: #64748b;
  font-size: 14px;
  font-weight: 800;
}

.lesson-author {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #334155;
  font-weight: 900;
}

.lesson-author img {
  border-radius: 999px;
}

.lesson-badge {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 0 12px;
  border-radius: 999px;
  background: var(--tc-soft-blue);
  color: var(--tc-primary);
  font-size: 13px;
  font-weight: 900;
}

.lesson-featured {
  position: relative;
  display: grid;
  min-height: 320px;
  place-items: center;
  border: 4px solid #dbeafe;
  border-radius: var(--tc-radius);
  background:
    radial-gradient(circle at 18% 20%, rgba(255, 255, 255, 0.9), transparent 24%),
    linear-gradient(135deg, #eff6ff, #dbeafe);
  box-shadow: inset 0 0 32px rgba(37, 99, 235, 0.1);
  overflow: hidden;
}

.lesson-featured img {
  width: 100%;
  height: 100%;
  max-height: 460px;
  object-fit: cover;
}

.lesson-featured-formula {
  color: var(--tc-primary);
  font-size: 72px;
  font-weight: 900;
  line-height: 1;
}

.lesson-featured-decor {
  position: absolute;
  font-size: 44px;
}

.lesson-featured-decor.top {
  top: 22px;
  left: 22px;
}

.lesson-featured-decor.bottom {
  right: 24px;
  bottom: 22px;
}

.post-content h2 {
  margin-top: 34px;
  margin-bottom: 14px;
  color: var(--tc-ink);
  font-size: 30px;
  line-height: 1.24;
  font-weight: 900;
}

.post-content h3 {
  margin-top: 26px;
  margin-bottom: 12px;
  color: #334155;
  font-size: 24px;
  line-height: 1.3;
  font-weight: 900;
}

.post-content p,
.post-content li {
  color: #475569;
  font-size: 18px;
  line-height: 1.78;
}

.post-content img {
  border-radius: var(--tc-radius);
  box-shadow: var(--tc-shadow-soft);
}

.note-box,
.example-box {
  margin: 24px 0;
  padding: 18px 20px;
  border-radius: var(--tc-radius);
}

.note-box {
  border-left: 5px solid #eab308;
  background: #fef9c3;
}

.note-box p {
  margin: 0;
  color: #854d0e;
  font-weight: 800;
}

.example-box {
  border: 2px dashed #93c5fd;
  background: #eff6ff;
}

.lesson-cta {
  margin-top: 44px;
  padding: 26px;
  border: 1px solid #bfdbfe;
  border-radius: var(--tc-radius);
  background: var(--tc-soft-blue);
  text-align: center;
}

.lesson-cta h2 {
  margin: 0 0 8px;
  color: var(--tc-ink);
  font-size: 22px;
  font-weight: 900;
}

.lesson-cta p {
  margin: 0 auto 18px;
  max-width: 560px;
  color: #475569;
}

.lesson-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 28px;
  padding-top: 24px;
  border-top: 1px solid #f1f5f9;
}

.lesson-tags span {
  color: #94a3b8;
  font-size: 14px;
  font-weight: 900;
}

.lesson-tags a {
  display: inline-flex;
  min-height: 28px;
  align-items: center;
  padding: 0 12px;
  border-radius: 999px;
  background: #f1f5f9;
  color: #475569;
  font-size: 13px;
  font-weight: 800;
}

.lesson-tags a:hover {
  background: #e2e8f0;
}

.lesson-comments {
  margin-top: 32px;
  padding: 30px;
}

.comments-title {
  margin: 0 0 22px;
  color: var(--tc-ink);
  font-size: 26px;
  font-weight: 900;
}

.comments-title::before {
  content: "💬";
  margin-right: 8px;
}

.comment-reply-title {
  margin: 0 0 14px;
  color: var(--tc-ink);
  font-size: 20px;
  font-weight: 900;
}

.comment-form p {
  margin: 0 0 16px;
}

.comment-form label {
  display: block;
  margin-bottom: 7px;
  color: var(--tc-ink);
  font-weight: 900;
}

.comment-form input,
.comment-form textarea {
  width: 100%;
  border: 1px solid var(--tc-border);
  border-radius: var(--tc-radius);
  background: #f8fafc;
  padding: 12px 14px;
}

.comment-form .tc-button,
.comment-form input[type="submit"],
.comment-form button[type="submit"] {
  display: inline-flex;
  width: auto;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  border: 0;
  border-radius: var(--tc-radius);
  background: var(--tc-primary) !important;
  color: var(--tc-white) !important;
  padding: 0 24px;
  font-weight: 900;
  cursor: pointer;
  opacity: 1;
}

.comment-form .tc-button:hover,
.comment-form input[type="submit"]:hover,
.comment-form button[type="submit"]:hover {
  background: var(--tc-primary-dark) !important;
}

.comment-form input[type="submit"]:disabled,
.comment-form button[type="submit"]:disabled {
  background: var(--tc-primary) !important;
  color: var(--tc-white) !important;
  cursor: not-allowed;
  opacity: 0.7;
}

.comment-list {
  display: grid;
  gap: 18px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.comment-list .comment-body {
  padding: 18px;
  border-radius: var(--tc-radius);
  background: #f8fafc;
}

.comment-list .children {
  margin: 16px 0 0 34px;
  padding: 0;
  list-style: none;
}

.comment-author {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--tc-ink);
  font-weight: 900;
}

.comment-author img {
  border-radius: 999px;
}

.comment-meta {
  margin: 4px 0 8px;
  color: #94a3b8;
  font-size: 13px;
}

.tc-math-render {
  color: var(--tc-ink);
  font-family: Georgia, "Times New Roman", serif;
  font-weight: 700;
  white-space: nowrap;
}

.tc-math-render.is-inline {
  display: inline-flex;
  align-items: center;
  vertical-align: middle;
  padding: 0 3px;
}

.tc-math-render.is-block {
  display: flex;
  justify-content: center;
  margin: 24px 0;
  padding: 18px;
  border-radius: var(--tc-radius);
  background: #f8fafc;
  font-size: 26px;
  overflow-x: auto;
}

.tc-rendered-frac {
  display: inline-grid;
  grid-template-rows: auto auto;
  align-items: center;
  justify-items: center;
  min-width: 1.2em;
  margin: 0 0.14em;
  line-height: 1.05;
  vertical-align: middle;
}

.tc-rendered-frac-num,
.tc-rendered-frac-den {
  display: block;
  padding: 0 0.16em;
}

.tc-rendered-frac-num {
  border-bottom: 1.8px solid currentColor;
}

.tc-rendered-frac-den {
  padding-top: 0.08em;
}


.tc-math-text {
  font-family: inherit;
  font-style: normal;
  font-weight: 700;
}

.tc-math-array {
  display: inline-flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: center;
  gap: 0.18em;
  vertical-align: middle;
  white-space: nowrap;
}

.tc-math-array-row {
  display: inline-flex;
  align-items: center;
  gap: 1.35em;
}

.tc-math-array-cell {
  display: inline-flex;
  align-items: center;
}

.tc-overline {
  display: inline-block;
  padding: 0 0.08em;
  border-top: 1.8px solid currentColor;
  line-height: 1.05;
}

.tc-sqrt {
  display: inline-flex;
  align-items: flex-start;
}

.tc-sqrt::before {
  content: "√";
  margin-right: 2px;
  font-size: 1.15em;
}

.tc-sqrt span {
  border-top: 1.8px solid currentColor;
  padding: 0 0.16em;
}

@media (max-width: 1020px) {
  .archive-layout,
  .single-view-layout {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 760px) {
  .archive-page,
  .single-page {
    padding-top: 22px;
  }

  .archive-hero {
    padding: 30px 22px;
  }

  .archive-hero h1 {
    font-size: 36px;
  }

  .archive-hero p {
    font-size: 17px;
  }

  .archive-toolbar {
    align-items: stretch;
    flex-direction: column;
  }

  .archive-sort {
    justify-content: space-between;
  }

  .archive-post-grid {
    grid-template-columns: 1fr;
  }

  .lesson-article,
  .lesson-comments {
    padding: 22px 16px;
  }

  .lesson-featured {
    min-height: 220px;
  }

  .lesson-featured-formula {
    font-size: 46px;
  }

  .post-content h2 {
    font-size: 26px;
  }

  .post-content h3 {
    font-size: 22px;
  }

  .post-content p,
  .post-content li {
    font-size: 17px;
  }
}
/* =========================================================
 * Xem thêm
 * ========================================================= */
.tc1-read-more {
    margin: 22px 0 8px;
    padding: 12px 24px;
    border: 1px solid #e4e8ef;
    border-radius: 14px;
    background: #f8fafc;
}

.tc1-read-more__title {
    margin: 0 0 14px;
    font-size: 22px;
    line-height: 1.3;
}

.tc1-read-more__list {
    margin: 0;
    padding-left: 22px;
}

.tc1-read-more__list li + li {
    margin-top: 9px;
}

.tc1-read-more__list a {
    color: inherit;
    font-weight: 600;
    text-decoration: none;
}

.tc1-read-more__list a:hover {
    text-decoration: underline;
}

/* =========================================================
 * Bài viết liên quan cùng chuyên mục
 * ========================================================= */
.tc1-related-posts {
    margin: 38px 0;
}

.tc1-related-posts__header {
    margin-bottom: 18px;
}

.tc1-related-posts__eyebrow {
    display: block;
    margin-bottom: 4px;
    color: #64748b;
    font-size: 13px;
    font-weight: 700;
    letter-spacing: .06em;
    text-transform: uppercase;
}

.tc1-related-posts__header h4 {
    margin: 0;
    font-size: 26px;
    line-height: 1.3;
}

.tc1-related-posts__grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
}

.tc1-related-card {
    overflow: hidden;
    border: 1px solid #e5e7eb;
    border-radius: 14px;
    background: #fff;
    box-shadow: 0 8px 24px rgba(15, 23, 42, .06);
}

.tc1-related-card__thumb {
    display: block;
    aspect-ratio: 16 / 9;
    overflow: hidden;
    background: #eef2f7;
}

.tc1-related-card__thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform .25s ease;
}

.tc1-related-card:hover .tc1-related-card__thumb img {
    transform: scale(1.035);
}

.tc1-related-card__placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    font-size: 42px;
}

.tc1-related-card__content {
    padding: 16px;
}

.tc1-related-card__category {
    display: inline-block;
    margin-bottom: 8px;
    font-size: 13px;
    font-weight: 700;
    text-decoration: none;
}

.tc1-related-card__title {
    margin: 0;
    font-size: 18px;
    line-height: 1.42;
}

.tc1-related-card__title a {
    color: inherit;
    text-decoration: none;
}

.tc1-related-card__title a:hover {
    text-decoration: underline;
}

.tc1-related-card__meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 6px;
    margin-top: 12px;
    color: #64748b;
    font-size: 13px;
}

@media (max-width: 900px) {
    .tc1-related-posts__grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 600px) {
    .tc1-read-more {
        padding: 18px;
    }

    .tc1-related-posts__grid {
        grid-template-columns: 1fr;
    }
}
.tc-single__excerpt {
    margin: 0 0 14px;
    padding-left: 10px;
    border-left: 3px solid #f97316;
    font-style: italic;
	font-size:16px;
    font-weight: 600;
}
/* Trang Full Page không sidebar */
.tc-full-page {
	width: 100%;
	min-height: 60vh;
}

.tc-full-page__container {
	width: min(100% - 32px, 1280px);
	max-width: 1280px;
	margin: 0 auto;
}

.tc-full-page__article {
	width: 100%;
	max-width: none;
	margin: 0;
}

.tc-full-page__header {
	margin-bottom: 24px;
}

.tc-full-page__header .entry-title {
	margin: 0;
	font-size: clamp(28px, 4vw, 44px);
	line-height: 1.2;
}

.tc-full-page__content {
	width: 100%;
	max-width: none;
}

/* Tránh thành phần bên trong bị giới hạn theo giao diện có sidebar */
.tc-full-page__content > * {
	max-width: none;
}

/* Riêng nội dung văn bản thông thường vẫn giữ độ rộng dễ đọc */
.tc-full-page__content > p,
.tc-full-page__content > ul,
.tc-full-page__content > ol,
.tc-full-page__content > blockquote {
	max-width: 900px;
}

/* Shortcode luyện tập chiếm toàn bộ chiều rộng */
.tc-full-page__content .luyen-bang-cuu-chuong,
.tc-full-page__content .lbc-app,
.tc-full-page__content .multiplication-practice {
	width: 100%;
	max-width: none;
}

@media (max-width: 767px) {
	.tc-full-page__container {
		width: min(100% - 20px, 1280px);
	}

	.tc-full-page__header {
		margin-bottom: 16px;
	}
}

/* =========================================================
   Exam figures & vertical calculations (v1.0.13)
   ========================================================= */
.tc1-inline-figure,
.tc1-geometry-figure {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  margin: 14px 0;
  min-height: 58px;
}

.tc1-geo-shape {
  display: inline-block;
  position: relative;
  flex: 0 0 auto;
  vertical-align: middle;
  margin: 4px 7px;
  width: 46px;
  height: 46px;
}

.tc1-geo-circle {
  border: 2px solid #0f172a;
  border-radius: 50%;
  background: #fff;
}

.tc1-geo-square {
  border: 2px solid #0f172a;
  background: #fff;
}

.tc1-geo-rectangle {
  width: 64px;
  height: 40px;
  border: 2px solid #0f172a;
  background: #fff;
}

.tc1-geo-triangle {
  width: 54px;
  height: 48px;
  background: #0f172a;
  clip-path: polygon(50% 0, 100% 100%, 0 100%);
}

.tc1-geo-triangle::after {
  content: "";
  position: absolute;
  inset: 4px 5px 3px;
  background: #fff;
  clip-path: polygon(50% 0, 100% 100%, 0 100%);
}

.tc1-geo-quadrilateral {
  width: 58px;
  height: 45px;
  background: #0f172a;
  clip-path: polygon(14% 0, 100% 10%, 84% 100%, 0 82%);
}

.tc1-geo-quadrilateral::after {
  content: "";
  position: absolute;
  inset: 4px;
  background: #fff;
  clip-path: polygon(14% 0, 100% 10%, 84% 100%, 0 82%);
}

.tc1-geo-parallelogram {
  width: 62px;
  height: 40px;
  border: 2px solid #0f172a;
  background: #fff;
  transform: skew(-18deg);
}

.tc1-geo-rhombus {
  width: 44px;
  height: 44px;
  border: 2px solid #0f172a;
  background: #fff;
  transform: rotate(45deg) scale(.82);
}

.tc1-vertical-calcs {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: 14px;
  margin: 12px 0 20px;
}

.tc1-vertical-calc {
  display: inline-block;
  min-width: 130px;
  padding: 12px 16px;
  border: 1px solid #cbd5e1;
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 4px 12px rgba(15, 23, 42, .05);
}

.tc1-vertical-calc pre {
  margin: 0;
  color: #0f172a;
  background: transparent;
  overflow: visible;
  font: 700 19px/1.45 "Courier New", Consolas, monospace;
  text-align: right;
  white-space: pre;
}

@media (max-width: 640px) {
  .tc1-geo-shape {
    margin: 4px 5px;
    transform-origin: center;
  }

  .tc1-vertical-calcs {
    gap: 10px;
  }

  .tc1-vertical-calc {
    min-width: 120px;
    padding: 10px 12px;
  }

  .tc1-vertical-calc pre {
    font-size: 18px;
  }
}

/* v1.0.25: Đề cương ôn tập KNTT - nội dung vẫn đẹp sau khi tắt plugin import. */
.tc1-outline{font-size:1em;line-height:1.75}.tc1-outline h2{margin-top:1.6em}.tc1-outline h3{margin-top:1.15em}.tc1-outline-note{margin:18px 0;padding:14px 16px;border-left:4px solid currentColor;background:#f6f8fb;border-radius:8px}.tc1-outline-example{margin:16px 0;padding:16px 18px;border:1px solid #e4e8ee;border-radius:12px;background:#fbfcfe}.tc1-outline-example h3{margin:0 0 8px;font-size:1.05em}.tc1-outline-exercises li,.tc1-outline-solutions li{margin-bottom:10px}.tc1-outline-solutions{padding:16px 18px 16px 36px;background:#f8fafc;border-radius:12px}@media(max-width:600px){.tc1-outline-example{padding:14px}.tc1-outline-solutions{padding:14px 14px 14px 32px}}

/* v1.0.26: nhóm bài theo dạng + khối tải Word đề cương. */
.tc1-outline-type{margin:18px 0 24px}.tc1-outline-type h3{margin-bottom:8px}.tc1-outline-download{margin:28px 0 6px;padding:18px 20px;border:1px solid var(--tc-border,#e2e8f0);border-radius:12px;background:var(--tc-soft,#f8fafc)}.tc1-outline-download h2{margin-top:0}.tc1-outline-download a{font-weight:700;text-decoration:underline}

/* v1.0.27: Bài tập theo chủ đề content */
.tc1-topic-exercise{font-size:16px;line-height:1.75}.tc1-topic-exercise h2{margin-top:30px}.tc1-topic-exercise h3{margin-top:22px}.tc1-topic-lead,.tc1-topic-note{padding:14px 16px;border-radius:12px;background:#f6f8fb}.tc1-topic-question,.tc1-topic-solution{padding:10px 0;border-bottom:1px dashed #e3e8ef}.tc1-topic-question:last-child,.tc1-topic-solution:last-child{border-bottom:0}.tc1-topic-solution-list{padding:4px 16px;border-left:3px solid #16a34a;background:#fbfefb;border-radius:0 10px 10px 0}@media(max-width:600px){.tc1-topic-exercise{font-size:15px}.tc1-topic-exercise h2{font-size:22px}}