:root {
  --ink: #0c1117;
  --muted: #5b6875;
  --blue: #135bff;
  --cyan: #00bbea;
  --lime: #c6ff00;
  --paper: #f7f8f6;
  --line: #dbe2e8;
  --shadow: 0 18px 45px rgba(20, 42, 62, .11);
  --radius: 28px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: #e9eef1;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
}

.scroll-progress { position: fixed; inset: 0 0 auto; height: 4px; z-index: 100; background: transparent; }
.scroll-progress span { display: block; width: 0; height: 100%; background: linear-gradient(90deg, var(--blue), var(--cyan), var(--lime)); }
.page-shell { width: min(100%, 1180px); margin: 0 auto; overflow: hidden; background: var(--paper); box-shadow: 0 0 80px rgba(20, 34, 45, .16); }
.hero {
  position: relative;
  min-height: 680px;
  padding: 88px 48px 42px;
  background: linear-gradient(180deg, rgba(255,255,255,.05), rgba(247,248,246,.5)), url("assets/fde-visual-foundation.png") top center / cover no-repeat;
}
.hero::after { content: ""; position: absolute; inset: auto 0 0; height: 180px; background: linear-gradient(transparent, var(--paper)); pointer-events: none; }
.brand-logo { position: absolute; top: 42px; right: 48px; z-index: 3; width: 220px; padding: 19px 22px; border-radius: 22px; background: var(--ink); }
.hero-card { position: relative; z-index: 2; width: min(790px, 78%); padding: 42px; border: 1px solid rgba(255,255,255,.85); border-radius: 34px; background: rgba(255,255,255,.88); box-shadow: var(--shadow); backdrop-filter: blur(16px); }
.eyebrow { display: flex; align-items: center; gap: 12px; font-size: 13px; font-weight: 800; letter-spacing: .05em; }
.eyebrow i { width: 22px; height: 22px; background: var(--lime); }
.hero h1 { margin: 30px 0 22px; font-size: clamp(38px, 4vw, 61px); line-height: 1.18; letter-spacing: -.05em; }
.hero h1 span { display: inline-block; margin-top: 10px; border-bottom: 7px solid var(--blue); padding-bottom: 12px; }
.hero-summary { max-width: 690px; margin: 0 0 26px; font-size: 22px; line-height: 1.75; }
.chips { display: flex; flex-wrap: wrap; gap: 9px; margin-bottom: 24px; }
.chips span { padding: 8px 14px; border-radius: 999px; color: #fff; background: var(--ink); font-size: 13px; font-weight: 700; }
.endorsement { display: grid; gap: 10px; padding: 15px 17px; border: 1px solid #34495c; border-radius: 18px; color: #fff; background: #0d151e; box-shadow: 0 12px 30px rgba(19,91,255,.14); }
.endorsement p { display: flex; align-items: center; gap: 12px; margin: 0; font-size: 15px; }
.endorsement b { display: grid; flex: 0 0 26px; height: 26px; place-items: center; border-radius: 8px; color: var(--ink); background: var(--lime); }
.endorsement p + p b { background: var(--cyan); }

.content-block { padding: 42px 48px; }
.overview { position: relative; z-index: 4; margin-top: -6px; padding-top: 0; }
.grid-four { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.interactive-card { position: relative; isolation: isolate; transition: transform .35s cubic-bezier(.2,.75,.25,1), box-shadow .35s ease, border-color .35s ease; }
.interactive-card::after { content: ""; position: absolute; inset: 0; z-index: -1; border-radius: inherit; opacity: 0; background: radial-gradient(340px circle at var(--mx, 50%) var(--my, 50%), rgba(19,91,255,.12), transparent 55%); transition: opacity .3s; pointer-events: none; }
.interactive-card:hover { z-index: 3; transform: translateY(-7px); box-shadow: 0 24px 55px rgba(18, 52, 79, .16); }
.interactive-card:hover::after { opacity: 1; }
.metric { min-height: 155px; padding: 25px; border: 1px solid #e7ebef; border-radius: 22px; background: rgba(255,255,255,.94); box-shadow: var(--shadow); }
.metric strong { display: block; color: var(--blue); font-size: 40px; line-height: 1; }
.metric strong.dark { color: var(--ink); font-size: 34px; }
.metric h2 { margin: 13px 0 8px; font-size: 19px; }
.metric p { margin: 0; color: var(--muted); font-size: 14px; }
.series-heading { display: flex; align-items: baseline; gap: 24px; margin: 32px 0 18px; }
.series-heading h2 { margin: 0; font-size: 22px; }
.series-heading span { color: var(--blue); font-size: 12px; font-weight: 800; letter-spacing: .08em; }
.practice-card { min-height: 280px; padding: 22px; border: 1px solid #e3e9ee; border-radius: 22px; background: rgba(255,255,255,.95); box-shadow: var(--shadow); --accent: var(--blue); }
.practice-card.cyan { --accent: var(--cyan); }.practice-card.lime { --accent: var(--lime); }
.practice-card header, .module-card header, .graduation header { display: flex; align-items: center; gap: 14px; padding-bottom: 17px; border-bottom: 1px solid var(--line); }
.practice-card header b, .module-card header > b, .graduation header > b { display: grid; flex: 0 0 auto; min-width: 46px; height: 32px; padding: 0 10px; place-items: center; border-radius: 999px; color: #fff; background: var(--accent); font-size: 13px; }
.practice-card.lime header b { color: var(--ink); }
.practice-card h3 { margin: 0; font-size: 19px; }
.practice-card ul { margin: 20px 0 0; padding: 0; list-style: none; }
.practice-card li { position: relative; margin: 0 0 15px; padding-left: 18px; color: var(--muted); font-size: 15px; line-height: 1.55; }
.practice-card li::before { content: ""; position: absolute; top: .62em; left: 0; width: 6px; height: 6px; border-radius: 50%; background: var(--accent); }
.keep-line { white-space: nowrap; }

.instructor { display: grid; grid-template-columns: 220px 1fr 290px; gap: 34px; align-items: center; margin-top: 38px; padding: 28px; border-radius: 28px; color: #fff; background: #111922; box-shadow: var(--shadow); }
.instructor figure { height: 250px; margin: 0; overflow: hidden; border: 1px solid #46627a; border-radius: 20px; background: #223242; }
.instructor figure img { width: 100%; height: 100%; object-fit: cover; object-position: center top; transition: transform .5s ease; }
.instructor:hover figure img { transform: scale(1.035); }
.instructor-info > span { color: var(--cyan); font-size: 12px; font-weight: 800; letter-spacing: .08em; }
.instructor-info h2 { margin: 8px 0 18px; font-size: 28px; }
.instructor-info ul { display: grid; gap: 10px; margin: 0; padding: 0; list-style: none; }
.instructor-info li { display: flex; align-items: center; gap: 11px; font-size: 17px; font-weight: 700; }
.instructor-info li b { display: grid; width: 25px; height: 25px; place-items: center; border-radius: 8px; color: #081018; background: var(--blue); font-size: 12px; }
.instructor-info li:first-child b { background: var(--lime); }
.instructor blockquote { margin: 0; padding-left: 34px; border-left: 1px solid #425568; font-size: 24px; font-weight: 800; line-height: 1.6; }
.instructor blockquote small { display: block; margin-bottom: 15px; color: var(--lime); font-size: 13px; }

.section-kicker { display: flex; align-items: center; gap: 15px; margin-bottom: 14px; font-size: 14px; font-weight: 800; letter-spacing: .04em; }
.section-kicker i { width: 9px; height: 34px; background: var(--blue); }
.section-kicker b { color: var(--blue); }.section-kicker span { margin-left: 8px; }
.content-block > h2, .work-loop h2 { margin: 0 0 34px; font-size: clamp(28px, 3vw, 38px); letter-spacing: -.03em; }
.flow-track { position: relative; padding: 8px 20px 0; }
.flow-line { position: absolute; top: 20px; left: 7%; width: 86%; height: 3px; overflow: hidden; background: #aebdca; }
.flow-line i { display: block; width: 0; height: 100%; background: linear-gradient(90deg, var(--blue), var(--cyan)); transition: width 1.3s cubic-bezier(.25,.9,.3,1); }
.work-loop.in-view .flow-line i { width: 72%; }
.flow-track ol { position: relative; display: grid; grid-template-columns: repeat(7, 1fr); margin: 0; padding: 0; list-style: none; }
.flow-track li { position: relative; padding-top: 48px; text-align: center; font-size: 14px; font-weight: 700; }
.flow-track li::before { content: ""; position: absolute; top: 4px; left: 50%; width: 24px; height: 24px; border-radius: 50%; background: var(--ink); transform: translateX(-50%); box-shadow: 0 0 0 7px var(--paper); }
.flow-track li:nth-child(-n+5)::before { background: var(--blue); }

.curriculum { padding-top: 55px; }
.module-grid { display: grid; gap: 18px; }.two-up { grid-template-columns: 1fr 1fr; }
.module-card { --accent: var(--blue); margin-bottom: 18px; padding: 26px; border: 1px solid #e1e7ec; border-radius: var(--radius); background: rgba(255,255,255,.95); box-shadow: var(--shadow); }
.module-card.cyan { --accent: var(--cyan); }
.module-card header { align-items: flex-start; }
.module-card header h3, .graduation h3 { margin: 0; font-size: 25px; }
.module-card header p, .graduation header p { margin: 5px 0 0; color: var(--muted); font-size: 13px; }
.module-card ol { display: grid; gap: 13px; margin: 22px 0 0; padding: 0; list-style: none; }
.module-card ol.two-column { grid-template: repeat(3, auto) / 1fr 1fr; grid-auto-flow: column; column-gap: 30px; }
.module-card.module-2 ol.two-column { grid-template-rows: repeat(6, auto); }
.module-card li { display: flex; align-items: flex-start; gap: 10px; min-width: 0; font-size: 15px; line-height: 1.45; }
.module-card li em { flex: 0 0 auto; padding: 4px 7px; border-radius: 7px; color: var(--accent); background: #eef5ff; font-size: 11px; font-style: normal; font-weight: 800; }
.module-card li.featured { color: var(--blue); font-weight: 800; }
.graduation { margin-top: 2px; padding: 28px; border-radius: 30px; color: #fff; background: #111922; box-shadow: var(--shadow); --accent: var(--lime); }
.graduation header { border-color: #3b4b59; }.graduation header > b { color: var(--ink); }
.graduation header p { color: #aab8c5; }
.graduation ol { display: grid; grid-template-columns: repeat(5, 1fr); gap: 14px; margin: 24px 0 0; padding: 0; list-style: none; }
.graduation li { display: grid; gap: 8px; min-height: 128px; padding: 18px; border: 1px solid #3c5164; border-radius: 18px; background: #1b2834; }
.graduation li b { color: var(--cyan); font-size: 12px; }.graduation li.accent b { color: var(--lime); }
.graduation li strong { font-size: 19px; }.graduation li span { color: #9fb0bf; font-size: 13px; }

.sandbox-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.dark-card { display: grid; grid-template-columns: auto 1fr; gap: 0 14px; padding: 27px; border-radius: 24px; color: #fff; background: #111922; box-shadow: var(--shadow); }
.dark-card > b { grid-row: 1 / span 2; color: var(--cyan); }.dark-card:nth-child(2n) > b { color: var(--lime); }
.dark-card h3 { margin: 0; font-size: 21px; }.dark-card p { grid-column: 2; margin: 13px 0 0; color: #aebdca; font-size: 15px; line-height: 1.6; }

.proof-grid { display: grid; grid-template-columns: repeat(3, 1fr); padding: 30px; border: 1px solid #e1e7ec; border-radius: 26px; background: #fff; box-shadow: var(--shadow); }
.proof-grid article { min-height: 160px; padding: 10px 30px; }.proof-grid article + article { border-left: 1px solid var(--line); }
.proof-grid b { color: var(--blue); }.proof-grid h3 { margin: 24px 0 12px; font-size: 20px; }.proof-grid p { margin: 0; color: var(--muted); font-size: 15px; line-height: 1.6; }
.pace { margin-top: 34px; padding: 32px; border-radius: 28px; color: #fff; background: #111922; box-shadow: var(--shadow); }
.pace header h2 { margin: 0 0 8px; font-size: 27px; }.pace header p { margin: 0; color: #aeb9c5; }
.pace > div { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 25px; }
.pace section { display: grid; gap: 10px; padding: 22px; border: 1px solid #395066; border-radius: 18px; background: #1b2936; }
.pace section b { color: var(--cyan); font-size: 20px; }.pace section:nth-child(2) b { color: var(--lime); }.pace section span { color: #91a3b2; font-size: 13px; }

footer { display: flex; align-items: center; justify-content: space-between; margin-top: 52px; padding: 46px 55px; color: #fff; background: #090f15; }
footer > div { display: flex; align-items: center; gap: 23px; }footer i { width: 13px; height: 70px; background: var(--lime); }footer h2 { margin: 0 0 8px; font-size: 32px; }footer p { margin: 0; color: #9aabb9; }footer img { width: 200px; }
.back-to-top { position: fixed; right: 28px; bottom: 28px; z-index: 50; display: grid; width: 54px; height: 54px; padding: 0; place-items: center; border: 1px solid rgba(255,255,255,.18); border-radius: 18px; color: #fff; background: rgba(12,17,23,.9); box-shadow: 0 14px 35px rgba(0,0,0,.22); opacity: 0; transform: translateY(18px); pointer-events: none; cursor: pointer; backdrop-filter: blur(12px); transition: .3s ease; }
.back-to-top.visible { opacity: 1; transform: translateY(0); pointer-events: auto; }.back-to-top:hover { color: var(--lime); transform: translateY(-4px); }.back-to-top svg { width: 27px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .7s ease, transform .7s cubic-bezier(.2,.8,.2,1); }
.reveal.is-visible { opacity: 1; transform: translateY(0); }

@media (max-width: 900px) {
  .page-shell { width: 100%; }
  .hero { min-height: 700px; padding: 100px 24px 34px; }
  .brand-logo { top: 24px; right: 24px; width: 170px; }
  .hero-card { width: 100%; padding: 30px 25px; }
  .content-block { padding: 34px 24px; }
  .grid-four { grid-template-columns: 1fr 1fr; }
  .practice-card { min-height: 245px; }
  .instructor { grid-template-columns: 170px 1fr; }
  .instructor figure { height: 220px; }
  .instructor blockquote { grid-column: 1 / -1; padding: 20px 0 0; border-top: 1px solid #425568; border-left: 0; }
  .two-up { grid-template-columns: 1fr; }
  .graduation ol { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 620px) {
  .hero { min-height: 760px; padding-top: 94px; }
  .brand-logo { width: 145px; padding: 13px 16px; border-radius: 16px; }
  .hero h1 { font-size: 38px; }
  .hero-summary { font-size: 18px; }
  .endorsement p { align-items: flex-start; font-size: 14px; line-height: 1.55; }
  .metric { min-height: 135px; }.metric strong { font-size: 34px; }.metric strong.dark { font-size: 27px; }
  .practice-grid { grid-template-columns: 1fr; }
  .practice-card { min-height: auto; }.practice-card li { font-size: 17px; }
  .series-heading { display: block; }.series-heading span { display: block; margin-top: 8px; }
  .instructor { grid-template-columns: 120px 1fr; gap: 20px; padding: 20px; }
  .instructor figure { height: 170px; }.instructor-info h2 { font-size: 24px; }.instructor-info li { font-size: 14px; }.instructor blockquote { font-size: 22px; }
  .flow-track { overflow-x: auto; }.flow-track ol { min-width: 620px; }
  .module-card ol.two-column { grid-template: none; grid-auto-flow: row; grid-template-columns: 1fr; }
  .module-card.module-2 ol.two-column { grid-template-rows: none; }
  .module-card li { font-size: 16px; }
  .graduation ol { grid-template-columns: 1fr 1fr; }.graduation li { min-height: 112px; }
  .sandbox-grid, .proof-grid, .pace > div { grid-template-columns: 1fr; }
  .proof-grid article + article { border-top: 1px solid var(--line); border-left: 0; }
  footer { align-items: flex-start; padding: 38px 24px; }footer img { width: 130px; }footer h2 { font-size: 25px; }footer p { font-size: 12px; }
  .back-to-top { right: 16px; bottom: 16px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
  .reveal { opacity: 1; transform: none; }
}