:root {
  --ink: #123b57;
  --ink-soft: #557387;
  --paper: #f6fbfe;
  --paper-soft: #eaf6fc;
  --blue: #239dda;
  --blue-dark: #0874b2;
  --line: rgba(18, 59, 87, .13);
  --nav-height: 82px;
  --page-gutter: clamp(24px, 6vw, 104px);
  font-family: "Microsoft YaHei UI", "PingFang SC", "Noto Sans CJK SC", sans-serif;
  color: var(--ink);
  background: var(--paper);
  font-synthesis: none;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-height) + 24px); }
body { margin: 0; min-width: 320px; }
button, input { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; text-decoration: none; }
button { color: inherit; }
[hidden] { display: none !important; }
:focus-visible { outline: 3px solid var(--blue); outline-offset: 4px; }

/* 顶部只保留品牌标志和账户入口。 */
.site-nav {
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 0 var(--page-gutter);
  background: rgba(255, 255, 255, .95);
  border-bottom: 1px solid rgba(35, 157, 218, .12);
  backdrop-filter: blur(16px);
}
.brand { display: inline-flex; align-items: center; flex: none; }
.brand-logo { display: block; width: 176px; height: auto; mix-blend-mode: multiply; }
.nav-actions { display: flex; align-items: center; justify-content: flex-end; gap: 10px; flex: none; }
.nav-button, .account-trigger { height: 40px; padding: 0 16px; border: 1px solid rgba(35, 157, 218, .22); border-radius: 7px; font-size: 13px; background: #fff; color: var(--blue-dark); cursor: pointer; transition: background .2s, border-color .2s; }
.nav-button:hover, .account-trigger:hover { background: var(--paper-soft); border-color: var(--blue); }
.nav-auth { background: var(--blue-dark); border-color: var(--blue-dark); color: #fff; }
.nav-auth:hover { background: var(--blue); color: #fff; }
.nav-points { display: inline-flex; align-items: center; gap: 8px; }
.point-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--blue); }
.account-menu { position: relative; }
.account-trigger { display: flex; align-items: center; gap: 8px; }
.account-name { max-width: 110px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.account-popover { position: absolute; right: 0; top: calc(100% + 10px); min-width: 150px; padding: 8px; background: #fff; border: 1px solid var(--line); border-radius: 8px; box-shadow: 0 16px 38px rgba(18, 59, 87, .12); opacity: 0; visibility: hidden; translate: 0 -5px; transition: .18s ease; }
.account-menu.open .account-popover { opacity: 1; visibility: visible; translate: 0; }
.account-popover button { display: block; width: 100%; padding: 10px; border: 0; text-align: left; background: none; cursor: pointer; }
.account-popover button:hover { background: var(--paper-soft); color: var(--blue-dark); }

/* 背景来自 AI 生成位图；遮罩仅保证前景文字可读。 */
.hero { position: relative; display: flex; align-items: center; min-height: min(860px, 100svh); overflow: hidden; padding: calc(var(--nav-height) + 64px) var(--page-gutter) 110px; background: #eaf6fc; }
.hero-image { position: absolute; inset: 0; background: url('/assets/future-academy-hero.webp') center 66% / cover no-repeat; animation: image-enter 1.2s ease-out both; }
.hero-shade { position: absolute; inset: 0; background: linear-gradient(90deg, rgba(247, 252, 255, .94), rgba(247, 252, 255, .76) 32%, rgba(247, 252, 255, .1) 63%, transparent); }
.hero-content { position: relative; z-index: 1; width: min(600px, 55%); animation: content-enter .7s ease-out both; }
.hero-eyebrow { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin: 0 0 24px; color: var(--blue-dark); font: 600 11px/1.6 Arial, sans-serif; letter-spacing: .18em; }
.hero-eyebrow span { font-family: "Microsoft YaHei UI", sans-serif; font-size: 12px; letter-spacing: .08em; }
.hero h1 { margin: 0; font-size: clamp(60px, 6.5vw, 88px); line-height: 1.15; font-weight: 800; letter-spacing: .02em; color: var(--blue-dark); }
.hero-tagline { margin: 24px 0 0; font-size: clamp(28px, 3vw, 40px); line-height: 1.5; font-weight: 600; letter-spacing: .015em; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 24px; margin-top: 34px; }
.primary-action { display: inline-flex; align-items: center; justify-content: space-between; gap: 32px; padding: 16px 22px; border-radius: 8px; color: #fff; background: var(--blue-dark); font-size: 15px; font-weight: 700; box-shadow: 0 10px 24px rgba(8, 116, 178, .16); transition: translate .2s, background .2s; }
.primary-action:hover { translate: 0 -2px; background: #086699; }
.primary-action span { font-size: 20px; }
.text-action { padding: 8px 0; border: 0; border-bottom: 1px solid rgba(8, 116, 178, .3); color: var(--blue-dark); font-size: 14px; cursor: pointer; background: none; }
.text-action:hover { border-color: var(--blue-dark); }
.scroll-cue { position: absolute; left: var(--page-gutter); bottom: 32px; display: flex; align-items: center; gap: 18px; color: var(--ink-soft); font-size: 11px; letter-spacing: .12em; }
.scroll-cue i { width: 58px; height: 1px; background: rgba(8, 116, 178, .35); }

/* 卡片承载子站链接，保留原分类、顺序、说明和积分信息。 */
.workbench { padding: 78px var(--page-gutter) 90px; background: var(--paper); }
.module-groups { max-width: 1440px; margin-inline: auto; }
.module-group + .module-group { margin-top: 68px; }
.module-group-heading { display: flex; align-items: center; justify-content: space-between; gap: 32px; margin-bottom: 26px; }
.module-group-heading h2 { position: relative; margin: 0; padding-left: 17px; color: var(--ink); font-size: clamp(25px, 2.5vw, 34px); line-height: 1.35; letter-spacing: -.03em; }
.module-group-heading h2::before { content: ''; position: absolute; left: 0; top: .15em; bottom: .15em; width: 4px; border-radius: 2px; background: var(--blue); }
.module-group-heading > p { max-width: 370px; margin: 0; color: var(--ink-soft); font-size: 13px; line-height: 1.8; }
.module-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; }
.module-card { display: flex; flex-direction: column; min-height: 272px; padding: 24px; border: 1px solid #dfedf5; border-radius: 14px; background: #fff; transition: translate .22s, border-color .22s, box-shadow .22s; }
.module-card:hover { translate: 0 -4px; border-color: #9ed4ed; box-shadow: 0 12px 28px rgba(18, 90, 129, .08); }
.module-top { display: flex; align-items: center; justify-content: space-between; gap: 8px; }
.module-number { color: var(--ink-soft); font: 10px/1.5 Arial, sans-serif; letter-spacing: .1em; }
.module-cost { padding: 5px 8px; border-radius: 5px; background: var(--paper-soft); color: #116a99; font-size: 10px; white-space: nowrap; }
.module-title { margin: 27px 0 10px; font-size: clamp(19px, 1.5vw, 23px); line-height: 1.4; font-weight: 700; }
.module-label { margin: 0 0 7px; font-size: 13px; line-height: 1.65; color: var(--blue-dark); font-weight: 600; }
.module-description { margin: 0 0 20px; color: var(--ink-soft); font-size: 12px; line-height: 1.85; }
.module-enter { display: flex; align-items: center; justify-content: space-between; margin-top: auto; padding-top: 14px; border-top: 1px solid #eef4f8; color: var(--blue-dark); font-size: 12px; }
.module-enter b { display: grid; place-items: center; width: 25px; height: 25px; border-radius: 50%; color: var(--blue-dark); background: var(--paper-soft); font-size: 17px; font-weight: 400; transition: background .2s, color .2s; }
.module-card:hover .module-enter b { background: var(--blue-dark); color: #fff; }
.module-loading { padding: 30px; color: var(--ink-soft); }
footer { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 30px var(--page-gutter); border-top: 1px solid #dceef8; background: var(--paper-soft); }
footer .brand-logo { width: 144px; }
footer p { margin: 0; color: var(--ink-soft); font-size: 12px; }

.modal { width: min(480px, calc(100vw - 30px)); padding: 36px; border: 0; color: var(--ink); background: var(--paper); box-shadow: 0 35px 100px rgba(3, 35, 62, .35); }
.modal::backdrop { background: rgba(4, 35, 62, .7); backdrop-filter: blur(8px); }
.modal-close { position: absolute; right: 18px; top: 14px; width: 34px; height: 34px; border: 0; background: none; color: var(--ink); font-size: 26px; cursor: pointer; }
.modal-heading p { margin: 0 0 12px; color: var(--blue); font: 10px Arial, sans-serif; letter-spacing: .2em; }
.modal-heading h2 { margin: 0 0 10px; font-size: 30px; letter-spacing: -.04em; }
.modal-heading span { color: var(--ink-soft); font-size: 13px; line-height: 1.7; }
.auth-tabs { display: grid; grid-template-columns: 1fr 1fr; margin: 28px 0 22px; border-bottom: 1px solid var(--line); }
.auth-tabs button { padding: 12px; border: 0; border-bottom: 3px solid transparent; background: none; cursor: pointer; }
.auth-tabs button.active { border-bottom-color: var(--blue); font-weight: 700; color: var(--blue-dark); }
.auth-form, .points-form { display: grid; gap: 16px; }
.auth-form label, .points-form label { display: grid; gap: 7px; font-size: 12px; font-weight: 700; }
.auth-form input, .points-form input { width: 100%; height: 48px; padding: 0 14px; border: 1px solid #b7c9d5; border-radius: 0; background: #fff; outline: 0; }
.auth-form input:focus, .points-form input:focus { border-color: var(--blue); box-shadow: 0 0 0 3px rgba(35, 157, 218, .14); }
.agreement-consent { display: flex; align-items: center; flex-wrap: wrap; gap: 5px; color: var(--ink-soft); font-size: 12px; line-height: 1.6; }
.agreement-check { display: inline-flex !important; align-items: center; grid-template-columns: none !important; gap: 7px !important; font-weight: 400 !important; cursor: pointer; }
.agreement-check input { width: 16px; height: 16px; flex: none; accent-color: var(--blue); cursor: pointer; }
.agreement-consent a { color: var(--blue-dark); text-decoration: underline; text-underline-offset: 3px; }
.agreement-consent a:hover { color: var(--blue-dark); }
.modal-primary { height: 48px; border: 0; background: var(--blue-dark); color: #fff; font-weight: 700; cursor: pointer; }
.modal-primary:hover { background: var(--blue); }
.form-message { min-height: 20px; margin: 0; color: #c05a00; font-size: 12px; }
.form-message.success { color: var(--blue-dark); }
.purchase-divider { display: flex; align-items: center; gap: 12px; margin: 25px 0 14px; color: #72889a; font-size: 11px; }
.purchase-divider::before, .purchase-divider::after { content: ''; flex: 1; height: 1px; background: var(--line); }
.purchase-link { display: flex; align-items: center; justify-content: space-between; padding: 15px; border: 1px solid var(--blue-dark); font-weight: 700; color: var(--blue-dark); }
.purchase-link:hover { background: var(--blue-dark); color: #fff; }


@keyframes content-enter { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }
@keyframes image-enter { from { opacity: .5; } to { opacity: 1; } }

@media (max-width: 1100px) {
  :root { --page-gutter: 32px; }
  .brand-logo { width: 150px; }
  .site-nav { gap: 20px; }
  .nav-button, .account-trigger { padding-inline: 12px; }
  .module-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .module-card { padding: 22px; }
}
@media (max-width: 850px) {
  :root { --nav-height: 74px; --page-gutter: 26px; }
  .hero { min-height: 740px; padding-top: calc(var(--nav-height) + 52px); }
  .hero-content { width: 63%; }
  .hero h1 { font-size: 64px; }
  .hero-tagline { font-size: 30px; }
  .hero-shade { background: linear-gradient(90deg, rgba(247,252,255,.96), rgba(247,252,255,.88) 40%, rgba(247,252,255,.28) 80%); }
  .hero-actions { gap: 20px; }
  .module-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .module-group-heading { align-items: flex-start; flex-direction: column; gap: 12px; }
  .module-group-heading > p { max-width: none; }
}
@media (max-width: 540px) {
  :root { --page-gutter: 20px; --nav-height: 66px; }
  .site-nav { padding-inline: 16px; gap: 10px; }
  .brand-logo { width: 126px; }
  .nav-actions { gap: 6px; }
  .nav-button, .account-trigger { height: 34px; padding-inline: 9px; font-size: 11px; }
  .account-name { max-width: 72px; }
  .point-dot { display: none; }
  .hero { min-height: 760px; min-height: max(730px, 100svh); align-items: flex-start; padding-top: calc(var(--nav-height) + 38px); padding-bottom: 170px; }
  .hero-image { top: 140px; background-position: 68% bottom; }
  .hero-shade { background: linear-gradient(180deg, #f2faff 0%, rgba(245,251,255,.97) 32%, rgba(245,251,255,.76) 53%, rgba(245,251,255,.12) 83%); }
  .hero-content { width: 100%; }
  .hero-eyebrow { margin-bottom: 20px; font-size: 10px; gap: 8px; }
  .hero-eyebrow span { font-size: 11px; }
  .hero h1 { font-size: clamp(48px, 14vw, 62px); }
  .hero-tagline { margin-top: 18px; font-size: 28px; line-height: 1.5; }
  .hero-actions { margin-top: 26px; gap: 15px; }
  .primary-action { padding: 14px 16px; gap: 20px; font-size: 13px; }
  .text-action { font-size: 12px; }
  .scroll-cue { bottom: 24px; }
  .workbench { padding-top: 48px; padding-bottom: 56px; }
  .module-group + .module-group { margin-top: 44px; }
  .module-group-heading { margin-bottom: 20px; }
  .module-group-heading h2 { font-size: 24px; }
  .module-group-heading > p { font-size: 12px; }
  .module-grid { grid-template-columns: 1fr; gap: 12px; }
  .module-card { min-height: 242px; padding: 22px; }
  .module-title { margin-top: 22px; font-size: 22px; }
  .module-description { font-size: 13px; }
  footer { padding-block: 24px; }
  footer .brand-logo { width: 118px; }
  footer p { font-size: 10px; }
  .modal { padding: 32px 22px 24px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}