:root {
  color-scheme: light;
  --paper: #fbf7ef;
  --paper-strong: #fffdf9;
  --ink: #382f24;
  --muted: #766957;
  --line: #dfd1bd;
  --orange: #f59e0b;
  --pink: #ec4899;
  --violet: #8b5cf6;
  --cyan: #22c4dc;
  --green: #35b98a;
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background:
    linear-gradient(90deg, transparent 0 46px, rgb(236 72 153 / 12%) 47px 48px, transparent 49px),
    repeating-linear-gradient(0deg, transparent 0 31px, rgb(118 105 87 / 8%) 32px 33px),
    var(--paper);
}
a { color: inherit; }
img { max-width: 100%; height: auto; display: block; }
.skip { position: fixed; top: -60px; left: 16px; z-index: 20; padding: 12px 16px; background: var(--ink); color: white; }
.skip:focus { top: 12px; }
.site-header, main, footer { width: min(1400px, calc(100% - 48px)); margin-inline: auto; }
.site-header { min-height: 84px; display: flex; align-items: center; justify-content: space-between; gap: 24px; border-bottom: 1px solid var(--line); }
.brand { min-height: 44px; display: inline-flex; align-items: center; text-decoration: none; font: 900 25px/1 Georgia, serif; letter-spacing: .14em; }
.brand span { color: var(--orange); } .brand i { color: var(--pink); font-style: normal; } .brand b { color: var(--cyan); }
nav { display: flex; align-items: center; gap: clamp(14px, 2.4vw, 34px); font-size: 14px; }
nav a { text-decoration: none; } nav a:hover, nav a:focus-visible { text-decoration: underline; text-underline-offset: 6px; }
.language { min-height: 44px; display: inline-flex; align-items: center; border: 1px solid var(--line); border-radius: 9px; padding: 9px 12px; background: var(--paper-strong); }
.hero { min-height: 680px; display: grid; grid-template-columns: minmax(0, .86fr) minmax(560px, 1.14fr); gap: clamp(44px, 6vw, 96px); align-items: center; padding: 80px 0 90px; }
.eyebrow { margin: 0 0 18px; color: #8d7d68; font: 800 12px/1.4 ui-monospace, SFMono-Regular, Menlo, monospace; letter-spacing: .18em; text-transform: uppercase; }
h1, h2, h3, p { margin-top: 0; }
h1 { max-width: 720px; font: 800 clamp(46px, 5.3vw, 78px)/1.02 Georgia, "Songti SC", serif; letter-spacing: -.04em; }
h1 em { color: var(--violet); font-style: normal; }
.lede { max-width: 680px; color: var(--muted); font-size: clamp(18px, 1.6vw, 23px); line-height: 1.7; }
.fine { color: var(--muted); font-size: 13px; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin: 28px 0 20px; }
.actions a { min-height: 48px; display: inline-flex; align-items: center; justify-content: center; padding: 0 20px; border: 1px solid var(--line); border-radius: 11px; background: var(--paper-strong); text-decoration: none; font-weight: 700; box-shadow: 0 8px 18px rgb(56 47 36 / 8%); }
.actions .primary { color: white; border-color: #4d3fb8; background: #5749bb; }
.actions a:hover, .actions a:focus-visible { transform: translateY(-2px); box-shadow: 0 12px 24px rgb(56 47 36 / 14%); }
.window { overflow: hidden; border: 1px solid #d4c1a4; border-radius: 24px; background: rgb(255 253 249 / 92%); box-shadow: 0 30px 70px rgb(75 57 34 / 16%); }
.window-bar { height: 56px; display: flex; align-items: center; gap: 9px; padding: 0 22px; border-bottom: 1px dashed #cfbea4; }
.window-bar span { width: 12px; height: 12px; border-radius: 50%; background: var(--orange); }
.window-bar span:nth-child(2) { background: var(--pink); } .window-bar span:nth-child(3) { background: var(--cyan); }
.window-bar strong { margin-left: 13px; color: #756753; font: 800 12px/1 ui-monospace, SFMono-Regular, Menlo, monospace; letter-spacing: .1em; }
.window img { width: 100%; }
.paper-section, .proof, .start { border: 1px solid var(--line); border-radius: 28px; background: rgb(255 253 249 / 92%); box-shadow: 0 18px 55px rgb(75 57 34 / 8%); }
.paper-section { padding: clamp(36px, 5vw, 74px); }
.paper-section h2, .proof h2, .start h2 { font: 800 clamp(34px, 4vw, 56px)/1.08 Georgia, "Songti SC", serif; }
.modes { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 40px; }
.modes article { min-height: 230px; padding: 28px; border-radius: 20px; background: #f6effd; }
.modes article:nth-child(2) { background: #eaf8f7; } .modes article:nth-child(3) { background: #fff0dd; }
.modes h3 { margin: 18px 0 9px; font: 800 26px/1 Georgia, serif; }
.modes p, .promises p, .proof p, .start p { color: var(--muted); line-height: 1.65; }
.mode { display: grid; width: 46px; height: 46px; place-items: center; border-radius: 12px; color: white; font: 900 26px/1 Georgia, serif; background: var(--violet); }
.mode.study { background: var(--green); } .mode.work { background: var(--orange); }
.proof { display: grid; grid-template-columns: .65fr 1.35fr; gap: 50px; align-items: center; margin-top: 26px; padding: clamp(28px, 4vw, 56px); }
.proof img { border: 1px solid var(--line); border-radius: 18px; box-shadow: 0 18px 42px rgb(56 47 36 / 12%); }
.promises { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; padding: 74px 0; }
.promises article { padding: 28px 24px; border-top: 3px solid var(--orange); background: rgb(255 253 249 / 75%); }
.promises article:nth-child(2) { border-color: var(--pink); } .promises article:nth-child(3) { border-color: var(--violet); } .promises article:nth-child(4) { border-color: var(--cyan); }
.promises strong { color: #9a8971; font: 800 12px/1 ui-monospace, monospace; }
.promises h3 { margin: 24px 0 10px; font-size: 19px; }
.start { margin-bottom: 80px; padding: clamp(36px, 5vw, 72px); }
pre { overflow-x: auto; margin: 30px 0; padding: 24px; border-radius: 16px; color: #e8fff7; background: #382f24; font: 14px/1.8 ui-monospace, SFMono-Regular, Menlo, monospace; }
footer { min-height: 110px; display: flex; align-items: center; justify-content: space-between; gap: 20px; border-top: 1px solid var(--line); color: #8d7d68; font: 700 11px/1.5 ui-monospace, monospace; letter-spacing: .1em; }

@media (max-width: 1050px) {
  .hero { grid-template-columns: 1fr; padding-top: 56px; }
  .window { max-width: 860px; }
  .proof { grid-template-columns: 1fr; }
  .promises { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 680px) {
  .site-header, main, footer { width: min(100% - 28px, 1400px); }
  .site-header { align-items: flex-start; padding: 20px 0; }
  nav { justify-content: flex-end; flex-wrap: wrap; gap: 12px 16px; }
  nav a:not(.language):not(:last-of-type) { display: none; }
  .hero { min-height: 0; gap: 32px; padding: 52px 0; }
  h1 { font-size: clamp(40px, 12vw, 58px); }
  .window-bar strong { font-size: 9px; }
  .modes, .promises { grid-template-columns: 1fr; }
  .paper-section, .proof, .start { border-radius: 20px; }
  footer { align-items: flex-start; flex-direction: column; justify-content: center; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; }
}