/* ==========================================================================
   ApplyEase Checkout — design system
   纯静态：仅 CSS + 系统字体栈，无框架、无外部依赖。
   ========================================================================== */
:root {
  color-scheme: light;

  /* 配色：以信任蓝为主色，中性灰打底，暖色用于边界提醒 */
  --bg: #eef2f8;
  --bg-grad-top: #f7f9fc;
  --ink: #101828;
  --ink-soft: #344054;
  --muted: #5d6b81;
  --line: #e2e8f2;
  --line-strong: #cbd5e6;
  --panel: #ffffff;
  --panel-tint: #f6f8fc;

  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-soft: #eef4ff;
  --primary-ring: rgba(37, 99, 235, 0.2);

  --warn-ink: #7c2d12;
  --warn-soft: #fff7ed;
  --warn-line: #fed7aa;

  /* 字号阶梯 */
  --text-xs: 12px;
  --text-sm: 13px;
  --text-base: 15px;
  --text-md: 16px;
  --text-lg: 18px;
  --text-xl: 22px;
  --text-2xl: 26px;

  /* 间距阶梯（4px 基础） */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-8: 32px;
  --space-10: 40px;
  --space-12: 56px;

  /* 圆角与阴影 */
  --radius-sm: 8px;
  --radius: 12px;
  --radius-lg: 16px;
  --radius-xl: 22px;
  --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.06);
  --shadow: 0 12px 32px rgba(16, 24, 40, 0.09);
  --shadow-lg: 0 28px 64px rgba(16, 24, 40, 0.16);
  --shadow-primary: 0 10px 24px rgba(37, 99, 235, 0.28);

  --maxw: 1120px;
  --header-h: 88px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-h);
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: var(--text-base);
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  position: relative;
}

h1,
h2,
h3,
p,
dl,
ul {
  margin: 0;
}

h1 {
  color: var(--ink);
  font-size: 40px;
  line-height: 1.16;
  letter-spacing: 0;
}

h2 {
  font-size: 27px;
  line-height: 1.25;
  letter-spacing: 0;
  color: var(--ink);
}

h3 {
  font-size: var(--text-lg);
  letter-spacing: 0;
  color: var(--ink);
}

p,
li,
dd {
  color: var(--muted);
  font-size: var(--text-base);
  line-height: 1.64;
}

a {
  color: var(--primary-dark);
}

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--primary-ring);
  outline-offset: 3px;
  border-radius: 6px;
}

/* --------------------------------------------------------------------------
   Top bar
   -------------------------------------------------------------------------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  gap: var(--space-5);
  padding: 14px clamp(18px, 5vw, 40px);
  border-bottom: 1px solid rgba(226, 232, 242, 0.9);
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: saturate(170%) blur(16px);
  -webkit-backdrop-filter: saturate(170%) blur(16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 850;
  text-decoration: none;
}

.brand-mark {
  position: relative;
  display: block;
  width: 32px;
  height: 32px;
  border-radius: 9px;
  background: linear-gradient(150deg, #3b82f6, #2563eb);
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.32);
}

.brand-a {
  position: absolute;
  left: 9px;
  top: 6px;
  font-size: 18px;
  font-weight: 900;
  line-height: 1;
}

.brand-e {
  position: absolute;
  right: 6px;
  top: 5px;
  font-size: 12px;
  font-weight: 900;
  line-height: 1;
}

.brand-name {
  font-size: var(--text-md);
  font-weight: 850;
  letter-spacing: 0;
}

.topbar nav {
  display: flex;
  align-items: center;
  gap: 2px;
  margin-left: auto;
}

.topbar nav a {
  padding: 8px 12px;
  border-radius: 8px;
  color: var(--muted);
  font-size: var(--text-base);
  font-weight: 650;
  text-decoration: none;
  transition: color 0.15s ease, background 0.15s ease;
}

.topbar nav a:hover {
  color: var(--ink);
  background: var(--panel-tint);
}

.topbar nav a[aria-current="page"] {
  color: var(--primary-dark);
  background: var(--primary-soft);
}

/* --------------------------------------------------------------------------
   Layout band rhythm — 每个 section 居中、统一最大宽度
   -------------------------------------------------------------------------- */
main {
  display: block;
}

section[id],
div[id] {
  scroll-margin-top: var(--space-3);
}

.section-heading[id] {
  scroll-margin-top: var(--space-3);
}

.workflow-band,
.scope-band,
.faq-band,
.contact-band {
  max-width: var(--maxw);
  margin-inline: auto;
  padding: var(--space-12) clamp(18px, 5vw, 40px);
}

.section-heading {
  display: grid;
  gap: var(--space-2);
  margin-bottom: var(--space-6);
  max-width: 64ch;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--primary);
  font-size: var(--text-xs);
  font-weight: 850;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.eyebrow::before {
  content: "";
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  opacity: 0.55;
}

/* --------------------------------------------------------------------------
   Hero
   -------------------------------------------------------------------------- */
.hero-band {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.82fr);
  gap: clamp(28px, 5vw, 60px);
  align-items: center;
  max-width: var(--maxw);
  margin-inline: auto;
  padding: clamp(52px, 7vw, 92px) clamp(18px, 5vw, 40px) clamp(44px, 6vw, 76px);
}

.hero-band::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 560px;
  z-index: -1;
  background:
    radial-gradient(1100px 440px at 16% -10%, rgba(37, 99, 235, 0.14), transparent 60%),
    radial-gradient(760px 320px at 100% 0%, rgba(59, 130, 246, 0.08), transparent 65%),
    linear-gradient(180deg, var(--bg-grad-top) 0%, var(--bg) 80%);
}

.hero-copy {
  display: grid;
  align-content: center;
  gap: var(--space-4);
}

.hero-subtitle {
  color: var(--ink-soft);
  font-size: 18px;
  line-height: 1.6;
  max-width: 40ch;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  padding-top: var(--space-2);
}

.primary-link,
.secondary-link {
  display: inline-grid;
  place-items: center;
  min-height: 48px;
  padding: 0 24px;
  border-radius: 11px;
  font-size: var(--text-md);
  font-weight: 800;
  text-decoration: none;
  transition: background 0.15s ease, transform 0.1s ease, box-shadow 0.15s ease,
    border-color 0.15s ease, color 0.15s ease;
}

.primary-link {
  background: var(--primary);
  color: #ffffff;
  box-shadow: var(--shadow-primary);
}

.primary-link:hover {
  background: var(--primary-dark);
  box-shadow: 0 14px 30px rgba(37, 99, 235, 0.34);
}

.primary-link:active,
.secondary-link:active {
  transform: translateY(1px);
}

.secondary-link {
  border: 1px solid var(--line-strong);
  background: #ffffff;
  color: var(--ink);
}

.secondary-link:hover {
  border-color: var(--primary);
  color: var(--primary-dark);
}

.product-preview {
  display: grid;
  gap: var(--space-3);
  padding: var(--space-5);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(246, 248, 252, 0.96)),
    var(--panel);
  box-shadow: var(--shadow);
}

.preview-window-bar {
  display: flex;
  gap: 7px;
  margin-bottom: var(--space-1);
}

.preview-window-bar span {
  width: 9px;
  height: 9px;
  border-radius: 999px;
  background: var(--line-strong);
}

.preview-card,
.preview-progress {
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: #ffffff;
  box-shadow: var(--shadow-sm);
}

.preview-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-4);
}

.preview-kicker {
  margin-bottom: 3px;
  color: var(--muted);
  font-size: var(--text-xs);
  font-weight: 750;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.preview-card strong {
  color: var(--ink);
  font-size: var(--text-md);
  font-weight: 800;
}

.preview-pill,
.preview-muted {
  white-space: nowrap;
  font-size: var(--text-xs);
  font-weight: 800;
}

.preview-pill {
  padding: 4px 9px;
  border-radius: 999px;
  background: #ecfdf3;
  color: #16803c;
}

.preview-muted {
  color: var(--muted);
}

.preview-progress {
  display: grid;
  gap: var(--space-2);
  padding: var(--space-4);
}

.preview-progress-meta {
  display: flex;
  justify-content: space-between;
  color: var(--muted);
  font-size: var(--text-sm);
  font-weight: 700;
}

.preview-track {
  height: 8px;
  overflow: hidden;
  border-radius: 999px;
  background: var(--line);
}

.preview-track span {
  display: block;
  width: 72%;
  height: 100%;
  border-radius: inherit;
  background: var(--primary);
}

.hero-disclaimer {
  margin-top: var(--space-5);
  padding: var(--space-4) var(--space-5);
  background: var(--warn-soft);
  border: 1px solid var(--warn-line);
  border-left: 4px solid #e6a23c;
  border-radius: var(--radius-sm);
  color: #6b3a00;
  font-size: var(--text-sm);
  line-height: 1.55;
}

.hero-disclaimer strong {
  color: #5a2d00;
}

/* workflow */
.workflow-band .section-heading {
  margin-bottom: var(--space-5);
}

.workflow-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-3);
  padding: 0;
  margin: 0;
  list-style: none;
  counter-reset: workflow;
}

.workflow-list li {
  position: relative;
  display: grid;
  gap: var(--space-2);
  padding: var(--space-5) var(--space-5) var(--space-5) 66px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: var(--shadow-sm);
  counter-increment: workflow;
}

.workflow-list li::before {
  content: counter(workflow);
  position: absolute;
  top: var(--space-5);
  left: var(--space-5);
  display: grid;
  width: 32px;
  height: 32px;
  place-items: center;
  border-radius: 10px;
  background: linear-gradient(150deg, #3b82f6, #2563eb);
  color: #ffffff;
  font-size: var(--text-base);
  font-weight: 900;
  box-shadow: 0 4px 10px rgba(37, 99, 235, 0.26);
}

.workflow-list strong {
  color: var(--ink);
  font-size: var(--text-base);
  font-weight: 800;
}

.workflow-list span {
  color: var(--muted);
  font-size: var(--text-sm);
  line-height: 1.5;
}

/* scope */
.scope-band {
  display: grid;
  grid-template-columns: minmax(280px, 1fr) minmax(280px, 0.92fr);
  gap: var(--space-6);
  align-items: start;
}

.scope-band > div:first-child .section-heading {
  margin-bottom: var(--space-4);
}

.school-grid {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.school-grid span {
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--panel);
  color: var(--ink-soft);
  font-size: var(--text-sm);
  font-weight: 700;
  box-shadow: var(--shadow-sm);
  transition: border-color 0.15s ease, color 0.15s ease;
}

.school-grid span:hover {
  border-color: var(--primary);
  color: var(--primary-dark);
}

.unsupported-panel {
  padding: var(--space-5) var(--space-6);
  border: 1px solid var(--warn-line);
  border-radius: var(--radius);
  background: var(--warn-soft);
}

.unsupported-panel h3 {
  margin-bottom: var(--space-3);
  color: var(--warn-ink);
  font-size: var(--text-md);
}

.unsupported-panel ul {
  display: grid;
  gap: var(--space-2);
  padding-left: 20px;
  margin: 0;
}

.unsupported-panel li {
  color: #6b3a00;
  font-size: var(--text-sm);
}

/* --------------------------------------------------------------------------
   FAQ
   -------------------------------------------------------------------------- */
.faq-band {
  background: transparent;
}

.faq-sections {
  display: grid;
  gap: var(--space-6);
}

.faq-group {
  display: grid;
  gap: var(--space-3);
}

.faq-group h3 {
  padding-bottom: var(--space-1);
  color: var(--ink);
  font-size: var(--text-md);
}

.accordion-list {
  display: grid;
  gap: var(--space-2);
}

.accordion-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.accordion-item[open] {
  border-color: var(--line-strong);
  box-shadow: var(--shadow);
}

.accordion-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  min-height: 54px;
  padding: var(--space-4) var(--space-5);
  color: var(--ink);
  font-size: var(--text-md);
  font-weight: 750;
  cursor: pointer;
  list-style: none;
  transition: background 0.12s ease;
}

.accordion-item summary:hover {
  background: var(--panel-tint);
}

.accordion-item summary::-webkit-details-marker {
  display: none;
}

.accordion-item summary::after {
  content: "+";
  display: grid;
  width: 28px;
  height: 28px;
  flex: 0 0 auto;
  place-items: center;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  color: var(--primary);
  font-size: 20px;
  line-height: 1;
  transition: transform 0.18s ease, background 0.15s ease, color 0.15s ease;
}

.accordion-item[open] summary {
  border-bottom: 1px solid var(--line);
  background: var(--panel-tint);
}

.accordion-item[open] summary::after {
  content: "−";
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

.accordion-item p {
  padding: 0 var(--space-5) var(--space-4);
  color: var(--muted);
  font-size: var(--text-base);
}

.accordion-item p:first-of-type {
  padding-top: var(--space-4);
}

/* --------------------------------------------------------------------------
   Contact
   -------------------------------------------------------------------------- */
.contact-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-4);
}

.contact-list article {
  display: grid;
  gap: var(--space-2);
  padding: var(--space-6);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--panel);
  box-shadow: var(--shadow-sm);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.contact-list article:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.contact-icon {
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border-radius: 13px;
  background: var(--primary-soft);
  font-size: 21px;
}

.contact-list h3 {
  font-size: var(--text-md);
}

.contact-list p {
  color: var(--ink);
  font-size: var(--text-base);
  font-weight: 700;
}

/* --------------------------------------------------------------------------
   Policy page
   -------------------------------------------------------------------------- */
.policy-page {
  max-width: var(--maxw);
  margin-inline: auto;
  padding: var(--space-12) clamp(18px, 5vw, 40px);
}

.policy-hero {
  display: grid;
  gap: var(--space-3);
  max-width: 76ch;
  margin-bottom: var(--space-8);
}

.policy-updated {
  color: var(--ink-soft);
  font-size: var(--text-base);
  font-weight: 700;
}

.policy-section {
  display: grid;
  gap: var(--space-3);
  max-width: 86ch;
  padding-block: var(--space-8);
  border-top: 1px solid var(--line);
}

.policy-section h2 {
  margin-bottom: var(--space-2);
}

.policy-section h3 {
  margin-top: var(--space-4);
  font-size: var(--text-md);
}

.policy-section ul {
  display: grid;
  gap: var(--space-2);
  padding-left: 22px;
}

.policy-section li {
  color: var(--muted);
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.site-footer {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: var(--space-8) clamp(18px, 5vw, 40px) var(--space-12);
  border-top: 1px solid var(--line);
  display: grid;
  gap: var(--space-3);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2) var(--space-3);
}

.footer-links a {
  color: var(--primary-dark);
  font-size: var(--text-sm);
  font-weight: 700;
  text-decoration: none;
}

.footer-links a:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.footer-links span {
  color: var(--line-strong);
}

.footer-copy {
  font-size: var(--text-xs);
  color: var(--muted);
}

.footer-note {
  max-width: 760px;
  color: var(--muted);
  font-size: var(--text-xs);
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */
@media (max-width: 960px) {
  .hero-band {
    grid-template-columns: 1fr;
    gap: var(--space-6);
  }

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

  .scope-band {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 720px) {
  h1 { font-size: 32px; }
  h2 { font-size: 23px; }
  .hero-subtitle { font-size: 16px; }

  .topbar {
    flex-wrap: wrap;
    gap: var(--space-2) var(--space-3);
    padding: 12px clamp(16px, 5vw, 24px);
  }

  .topbar nav {
    order: 3;
    width: 100%;
    margin-left: 0;
    flex-wrap: wrap;
    gap: 4px;
  }

  .topbar nav a {
    white-space: nowrap;
  }

  .preview-card {
    align-items: flex-start;
    flex-direction: column;
    gap: var(--space-2);
  }

  .workflow-band,
  .scope-band,
  .faq-band,
  .contact-band {
    padding-block: clamp(36px, 8vw, 48px);
  }

  .workflow-list {
    grid-template-columns: 1fr;
  }

  .contact-list {
    grid-template-columns: 1fr;
  }

  .hero-actions .primary-link,
  .hero-actions .secondary-link {
    flex: 1 1 auto;
  }

}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto !important;
    transition: none !important;
  }
}