:root {
  --paper: #f7f8f6;
  --surface: #ffffff;
  --ink: #132238;
  --text: #27364b;
  --muted: #657084;
  --line: #dce2ea;
  --teal: #0f766e;
  --blue: #2458c5;
  --gold: #a66a10;
  --rose: #b42348;
  --green: #26734d;
  --shadow: 0 18px 45px rgba(19, 34, 56, 0.13);
  --radius: 8px;
  --container: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

html,
body {
  max-width: 100%;
  overflow-x: hidden;
}

body {
  margin: 0;
  color: var(--text);
  background: var(--paper);
  font-family: Inter, -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.68;
  letter-spacing: 0;
}

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

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

a:hover {
  color: var(--blue);
}

:focus-visible {
  outline: 3px solid rgba(36, 88, 197, 0.45);
  outline-offset: 3px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid rgba(220, 226, 234, 0.85);
  backdrop-filter: blur(14px);
}

.nav-wrap {
  width: min(var(--container), calc(100% - 40px));
  min-height: 68px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 800;
  white-space: nowrap;
}

.brand-mark {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  color: #fff;
  background: var(--ink);
  border-radius: 6px;
  font-size: 15px;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.brand-text small {
  margin-top: 2px;
  color: var(--muted);
  font-size: 12px;
  font-weight: 600;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--ink);
  cursor: pointer;
}

.nav-toggle span,
.nav-toggle span::before,
.nav-toggle span::after {
  display: block;
  width: 18px;
  height: 2px;
  margin: 0 auto;
  background: currentColor;
  content: "";
}

.nav-toggle span::before {
  transform: translateY(-6px);
}

.nav-toggle span::after {
  transform: translateY(4px);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  color: var(--ink);
  font-size: 15px;
  font-weight: 700;
}

.site-nav a {
  padding: 10px 12px;
  border-radius: 6px;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  color: var(--blue);
  background: rgba(36, 88, 197, 0.08);
}

.hero {
  min-height: 74vh;
  color: #fff;
  background-image:
    linear-gradient(90deg, rgba(12, 24, 42, 0.86), rgba(12, 24, 42, 0.55) 45%, rgba(12, 24, 42, 0.1)),
    url("../img/hero-study-us-undergrad.png");
  background-position: center;
  background-size: cover;
}

.hero-inner {
  width: min(var(--container), calc(100% - 40px));
  min-height: 74vh;
  margin: 0 auto;
  padding: 74px 0 58px;
  display: grid;
  align-content: center;
}

.hero-copy {
  width: 100%;
  max-width: 650px;
  min-width: 0;
}

.eyebrow {
  margin: 0 0 14px;
  color: #f1c55d;
  font-size: 14px;
  font-weight: 800;
}

.hero h1,
.page-hero h1 {
  margin: 0;
  color: inherit;
  font-size: 58px;
  line-height: 1.08;
  letter-spacing: 0;
  overflow-wrap: anywhere;
}

.hero p {
  max-width: 580px;
  margin: 22px 0 0;
  color: rgba(255, 255, 255, 0.88);
  font-size: 19px;
}

.hero-actions,
.section-actions,
.form-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.btn {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 16px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-weight: 800;
  cursor: pointer;
}

.btn-primary {
  color: #fff;
  background: var(--teal);
}

.btn-primary:hover {
  color: #fff;
  background: #0b5f59;
}

.btn-secondary {
  color: var(--ink);
  background: #fff;
}

.btn-secondary:hover {
  color: var(--ink);
  background: #eef5ff;
}

.btn-outline {
  color: var(--ink);
  border-color: var(--line);
  background: var(--surface);
}

.section,
.page-shell {
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
}

.section {
  padding: 64px 0;
}

.section.tight {
  padding-top: 34px;
}

.section-header {
  max-width: 760px;
  margin-bottom: 28px;
}

.section-kicker {
  margin: 0 0 8px;
  color: var(--rose);
  font-size: 13px;
  font-weight: 900;
}

.section h2,
.article h2,
.info-panel h2 {
  margin: 0;
  color: var(--ink);
  font-size: 32px;
  line-height: 1.22;
}

.section-header p,
.page-hero p,
.article-lede {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 17px;
}

.grid {
  display: grid;
  gap: 18px;
}

.grid.cols-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

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

.card,
.article-card,
.metric-card,
.toc-card,
.notice,
.contact-card,
.calculator {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.card,
.article-card,
.metric-card,
.toc-card,
.notice,
.contact-card {
  padding: 22px;
}

.card h3,
.article-card h3,
.contact-card h3,
.calculator h3 {
  margin: 0 0 8px;
  color: var(--ink);
  font-size: 20px;
  line-height: 1.28;
}

.card p,
.article-card p,
.contact-card p,
.metric-card p,
.notice p {
  margin: 0;
  color: var(--muted);
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 26px;
  margin-bottom: 14px;
  padding: 3px 9px;
  border-radius: 999px;
  color: var(--ink);
  background: #eef2f7;
  font-size: 12px;
  font-weight: 800;
}

.tag.teal {
  color: #075e59;
  background: #ddf4f1;
}

.tag.gold {
  color: #7a4b06;
  background: #fff0cc;
}

.tag.rose {
  color: #8e1737;
  background: #ffe4eb;
}

.tag.green {
  color: #166534;
  background: #e5f5ea;
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(320px, 0.85fr);
  gap: 34px;
  align-items: start;
}

.info-panel {
  padding: 28px;
  border-left: 5px solid var(--teal);
  background: #ffffff;
  box-shadow: var(--shadow);
}

.check-list,
.plain-list,
.toc-list {
  padding: 0;
  margin: 18px 0 0;
  list-style: none;
}

.check-list li,
.plain-list li {
  position: relative;
  padding-left: 24px;
  margin: 10px 0;
}

.check-list li::before {
  position: absolute;
  left: 0;
  color: var(--green);
  font-weight: 900;
  content: "✓";
}

.plain-list li::before {
  position: absolute;
  left: 0;
  color: var(--gold);
  font-weight: 900;
  content: "•";
}

.article-grid {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 24px;
  align-items: start;
}

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

.feature-row {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 16px;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.feature-row:last-child {
  border-bottom: 0;
}

.feature-row strong {
  color: var(--ink);
}

.feature-row p {
  margin: 0;
  color: var(--muted);
}

.ad-slot {
  width: 100%;
  min-height: 96px;
  display: grid;
  place-items: center;
  padding: 18px;
  border: 1px dashed #b7c2d0;
  border-radius: var(--radius);
  color: #5b6574;
  background: repeating-linear-gradient(135deg, #f2f5f9, #f2f5f9 10px, #edf1f6 10px, #edf1f6 20px);
  text-align: center;
}

.ad-slot span {
  display: block;
  color: var(--ink);
  font-weight: 900;
}

.ad-slot small {
  display: block;
  margin-top: 3px;
  font-size: 12px;
}

.ad-slot.wide {
  min-height: 112px;
  margin: 26px 0;
}

.page-hero {
  color: #fff;
  background:
    linear-gradient(90deg, rgba(19, 34, 56, 0.94), rgba(15, 118, 110, 0.72)),
    #132238;
}

.page-hero-inner {
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
  padding: 62px 0;
}

.breadcrumbs {
  margin: 0 0 16px;
  color: rgba(255, 255, 255, 0.76);
  font-size: 14px;
}

.breadcrumbs a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 36px;
  padding: 54px 0 72px;
}

.article {
  min-width: 0;
}

.article h2 {
  margin-top: 36px;
  padding-top: 8px;
}

.article h3 {
  margin: 28px 0 8px;
  color: var(--ink);
  font-size: 22px;
}

.article p {
  margin: 12px 0;
}

.article a {
  color: var(--blue);
  font-weight: 800;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.article table {
  width: 100%;
  margin: 20px 0;
  border-collapse: collapse;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.article th,
.article td {
  padding: 13px 14px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.article th {
  color: var(--ink);
  background: #eef2f7;
}

.article tr:last-child td {
  border-bottom: 0;
}

.article-side {
  position: sticky;
  top: 92px;
  display: grid;
  gap: 18px;
}

.toc-card h2 {
  font-size: 18px;
}

.toc-list {
  margin-top: 10px;
}

.toc-list a {
  display: block;
  padding: 7px 0;
  color: var(--muted);
  border-bottom: 1px solid #edf1f6;
  font-size: 14px;
}

.toc-list a:hover {
  color: var(--blue);
}

.notice {
  border-left: 5px solid var(--gold);
}

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

.timeline {
  display: grid;
  gap: 14px;
  margin-top: 22px;
}

.timeline-item {
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 18px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.timeline-date {
  color: var(--rose);
  font-weight: 900;
}

.timeline-item h3 {
  margin-top: 0;
}

.calculator {
  padding: 24px;
}

.calc-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 18px;
}

label {
  display: grid;
  gap: 6px;
  color: var(--ink);
  font-weight: 800;
}

input,
select,
textarea {
  width: 100%;
  min-height: 44px;
  padding: 10px 12px;
  border: 1px solid #cbd5e1;
  border-radius: 6px;
  color: var(--ink);
  background: #fff;
  font: inherit;
}

textarea {
  min-height: 150px;
  resize: vertical;
}

.calc-result {
  margin-top: 18px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #f8fafc;
}

.calc-result strong {
  display: block;
  color: var(--ink);
  font-size: 26px;
}

.contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 24px;
}

.contact-form {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.form-grid {
  display: grid;
  gap: 14px;
}

.site-footer {
  color: #dfe7f2;
  background: #101c2d;
}

.footer-inner {
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
  padding: 44px 0 28px;
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 34px;
}

.footer-inner h2,
.footer-inner h3 {
  margin: 0 0 10px;
  color: #fff;
}

.footer-inner p {
  margin: 0;
  color: #b8c5d8;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px 22px;
}

.footer-links a {
  color: #dfe7f2;
}

.footer-bottom {
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
  padding: 18px 0 28px;
  border-top: 1px solid rgba(255, 255, 255, 0.13);
  color: #aebbd0;
  font-size: 13px;
}

.cookie-banner {
  position: fixed;
  right: 18px;
  bottom: 18px;
  z-index: 70;
  width: min(460px, calc(100% - 36px));
  max-height: calc(100vh - 36px);
  overflow: auto;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
}

.cookie-banner p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.cookie-banner a {
  color: var(--blue);
  font-weight: 800;
}

.cookie-actions {
  display: flex;
  gap: 10px;
  justify-content: flex-end;
  margin-top: 14px;
}

.hidden {
  display: none !important;
}

@media (max-width: 980px) {
  .grid.cols-3,
  .grid.cols-4,
  .split,
  .article-grid,
  .article-layout,
  .contact-grid,
  .footer-inner {
    grid-template-columns: 1fr;
  }

  .article-side {
    position: static;
  }

  .hero h1,
  .page-hero h1 {
    font-size: 44px;
  }
}

@media (max-width: 760px) {
  .nav-wrap {
    width: min(var(--container), calc(100% - 28px));
    min-height: 62px;
  }

  .nav-toggle {
    display: inline-grid;
    place-items: center;
  }

  .site-nav {
    position: absolute;
    top: 62px;
    left: 14px;
    right: 14px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: #fff;
    box-shadow: var(--shadow);
  }

  .site-nav.open {
    display: flex;
  }

  .hero {
    min-height: 650px;
    background-position: 62% center;
  }

  .hero-inner {
    min-height: 650px;
    width: min(var(--container), calc(100% - 28px));
    padding: 54px 0 42px;
  }

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

  .hero p,
  .page-hero p,
  .article-lede {
    font-size: 16px;
  }

  .section,
  .page-shell,
  .page-hero-inner,
  .footer-inner,
  .footer-bottom {
    width: min(var(--container), calc(100% - 28px));
  }

  .section {
    padding: 46px 0;
  }

  .feature-row,
  .timeline-item,
  .calc-grid {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 480px) {
  .hero h1,
  .page-hero h1 {
    font-size: 28px;
    line-height: 1.18;
  }

  .brand-text small {
    display: none;
  }

  .hero-actions,
  .section-actions,
  .form-actions,
  .cookie-actions {
    flex-direction: column;
  }

  .cookie-banner {
    right: 14px;
    bottom: 14px;
    width: calc(100% - 28px);
  }

  .btn {
    width: 100%;
  }
}