/* ============================================================
 * Jump 官网 — 编辑部 / 档案感
 * 暖纸 · 衬线标题 · 发丝规则线 · 颗粒质感 · 错峰载入
 * ============================================================ */

*,
*::before,
*::after { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.55;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

/* 全局颗粒质感 */
body::after {
  content: '';
  position: fixed; inset: 0; z-index: 1; pointer-events: none;
  opacity: var(--grain-opacity);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

:focus-visible { outline: 2px solid var(--focus-ring); outline-offset: 3px; border-radius: 4px; }

.wrap {
  width: 100%; max-width: 1080px; margin: 0 auto; padding: 0 30px;
  position: relative; z-index: 2;
}

/* 小标签（kicker / 序号） */
.kicker {
  font-family: var(--font-ui);
  font-size: 12px; font-weight: 600; letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--ink-soft);
}

/* ---------- 中文：加大字距与行距 ---------- */
html[lang="zh-CN"] body { letter-spacing: 0.035em; line-height: 1.72; }
html[lang="zh-CN"] .hero h1,
html[lang="zh-CN"] .feature h2,
html[lang="zh-CN"] .download h2,
html[lang="zh-CN"] .details__head h2,
html[lang="zh-CN"] .row__text h3,
html[lang="zh-CN"] .contact__title { letter-spacing: 0.08em; line-height: 1.3; }
html[lang="zh-CN"] .kicker { letter-spacing: 0.26em; }
html[lang="zh-CN"] .hero__sub,
html[lang="zh-CN"] .feature__desc,
html[lang="zh-CN"] .row__text p,
html[lang="zh-CN"] .details__item p { letter-spacing: 0.04em; line-height: 1.9; }

/* ---------- 错峰载入 ---------- */
.rise { opacity: 0; animation: rise 0.9s cubic-bezier(0.2, 0.7, 0.2, 1) both; animation-delay: var(--d, 0s); }
@keyframes rise { from { opacity: 0; transform: translateY(18px); } to { opacity: 1; transform: none; } }

.reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.8s ease, transform 0.8s ease; }
.reveal.is-in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .rise, .reveal { opacity: 1; transform: none; animation: none; transition: none; }
}

/* ---------- 浮动切换（右上角，低调） ---------- */
.controls {
  position: fixed; top: 16px; right: 20px; z-index: 80;
  display: flex; align-items: center; gap: 11px;
  padding: 6px 13px; border-radius: 999px;
  background: var(--nav-bg);
  border: 1px solid var(--rule-soft);
  backdrop-filter: saturate(140%) blur(14px);
  -webkit-backdrop-filter: saturate(140%) blur(14px);
}
.controls .link-btn { font-size: 13px; color: var(--ink-faint); }
.controls .link-btn:hover { color: var(--ink); }
.controls__sep { width: 1px; height: 12px; background: var(--rule); }

.link-btn {
  border: none; background: none; padding: 0; cursor: pointer;
  font-family: var(--font-ui); font-size: 14px; color: var(--ink-soft);
  transition: color 0.16s ease;
}
.link-btn:hover { color: var(--ink); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: 48px; padding: 0 28px;
  font-family: var(--font-ui); font-size: 15px; font-weight: 500;
  border-radius: 16px; cursor: pointer; border: 1px solid transparent;
  transition: transform 0.14s ease, background 0.18s ease, color 0.18s ease, border-color 0.18s ease;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn--primary { background: var(--ink); color: var(--paper); }
.btn--primary:hover { background: var(--ink-soft); }
.btn--ghost { background: transparent; color: var(--ink); border-color: var(--rule); }
.btn--ghost:hover { background: var(--surface-hover); }

/* ---------- Hero ---------- */
/* 不用 overflow:hidden，否则会裁掉 hero 截图向下的投影；横向溢出由 body 控制 */
.hero { position: relative; text-align: center; padding: 120px 0 0; }

.hero__aura {
  position: absolute; z-index: 0; top: -180px; left: 50%;
  width: 1100px; height: 620px; transform: translateX(-50%);
  background: var(--gradient-brand); filter: blur(120px); opacity: 0.16; pointer-events: none;
}
[data-theme="dark"] .hero__aura { opacity: 0.26; }

.hero__eyebrow {
  margin: 0 0 26px;
  font-size: clamp(18px, 1.5vw, 22px);
  text-transform: none;
}

.hairline-brand { width: 56px; height: 2px; margin: 0 auto 26px; background: var(--gradient-brand); border-radius: 2px; }

.hero h1 {
  margin: 0 auto 24px; max-width: 15ch;
  font-family: var(--font-display); font-weight: 500;
  font-size: clamp(44px, 6.6vw, 84px); line-height: 1.0; letter-spacing: -0.02em;
}
.hero h1 em { font-style: italic; }

.hero__sub {
  margin: 0 auto 36px; max-width: 40ch;
  font-size: clamp(18px, 2vw, 21px); line-height: 1.45; color: var(--ink-soft);
}

.hero__cta { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.hero__note { margin: 20px 0 0; font-family: var(--font-ui); font-size: 13px; letter-spacing: 0.02em; color: var(--ink-faint); }
.hero__shot { margin-top: 70px; }

/* ---------- 图片框（原比例，不裁切） ---------- */
.shot {
  position: relative; border-radius: 14px; overflow: hidden;
  background: var(--card); border: 1px solid var(--rule); box-shadow: var(--shot-shadow);
}
.shot img { width: 100%; height: auto; }
.shot__ph {
  aspect-ratio: 16 / 10; display: flex; align-items: center; justify-content: center;
  font-family: var(--font-ui); color: var(--ink-faint); font-size: 13px; background: var(--paper-2);
}

/* ---------- 重点功能（居中大屏） ---------- */
.feature { padding: 110px 0; text-align: center; border-top: 1px solid var(--rule-soft); }
.feature--alt { background: var(--paper-2); }
/* 紧接 hero 的首个功能去掉顶部分隔线，避免横线穿过 hero 截图的阴影 */
#features > .feature:first-child { border-top: none; padding-top: 130px; }

.feature__meta { margin: 0 0 18px; }

.feature h2 {
  margin: 0 auto 20px; max-width: 17ch;
  font-family: var(--font-display); font-weight: 500;
  font-size: clamp(30px, 4.4vw, 52px); line-height: 1.06; letter-spacing: -0.018em;
}
.feature__desc { margin: 0 auto 54px; max-width: 40ch; font-size: clamp(17px, 1.8vw, 20px); line-height: 1.5; color: var(--ink-soft); }
.feature .shot { max-width: 980px; margin: 0 auto; }

/* ---------- 交错行 05–09 ---------- */
.row { padding: 76px 0; border-top: 1px solid var(--rule-soft); }
.row__grid { display: grid; grid-template-columns: minmax(0, 0.84fr) minmax(0, 1.16fr); gap: 58px; align-items: center; }
.row--reverse .row__media { order: -1; }

/* 交错行配图较小，圆角相应收小 */
.row__media { border-radius: 9px; }
.row__text .feature__meta { margin-bottom: 18px; }
.row__text h3 {
  margin: 0 0 16px;
  font-family: var(--font-display); font-weight: 500;
  font-size: clamp(24px, 2.9vw, 34px); line-height: 1.1; letter-spacing: -0.015em;
}
.row__text p { margin: 0; font-size: 17px; line-height: 1.55; color: var(--ink-soft); max-width: 38ch; }

.kbd {
  display: inline-block; margin-top: 16px; padding: 3px 9px;
  border: 1px solid var(--rule); border-radius: 4px;
  font-family: var(--font-ui); font-size: 12px; color: var(--ink-soft);
}

/* ---------- 细节三项 ---------- */
.details { padding: 116px 0; border-top: 1px solid var(--rule-soft); }
.details__head { text-align: center; max-width: 640px; margin: 0 auto 60px; }
.details__head h2 {
  margin: 0; font-family: var(--font-display); font-weight: 500;
  font-size: clamp(26px, 3.4vw, 40px); line-height: 1.1; letter-spacing: -0.018em;
}
.details__grid { display: grid; grid-template-columns: repeat(3, 1fr); }
.details__item { padding: 0 30px; border-left: 1px solid var(--rule-soft); }
.details__item:first-child { border-left: none; padding-left: 0; }
.details__item:last-child { padding-right: 0; }
.details__item h3 { margin: 0 0 12px; font-family: var(--font-display); font-size: 22px; font-weight: 500; letter-spacing: -0.01em; }
.details__item p { margin: 0; font-size: 16px; line-height: 1.55; color: var(--ink-soft); }

/* ---------- 下载 ---------- */
.download { padding: 130px 0; text-align: center; border-top: 1px solid var(--rule); }
.download h2 {
  margin: 0 0 16px; font-family: var(--font-display); font-weight: 500;
  font-size: clamp(34px, 5vw, 60px); line-height: 1.0; letter-spacing: -0.02em;
}
.download h2 em { font-style: italic; }
.download__sub { margin: 0 auto 44px; max-width: 38ch; font-size: 19px; color: var(--ink-soft); }

.dl-row { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; margin: 0 auto 22px; }
.dl-btn { flex-direction: column; height: auto; padding: 14px 26px; gap: 3px; border-radius: 16px; line-height: 1.2; }
.dl-btn__meta { font-family: var(--font-ui); font-size: 12px; font-weight: 400; opacity: 0.72; }

.download__req { font-family: var(--font-ui); font-size: 13px; color: var(--ink-faint); }

/* ---------- 封底 / 联系 ---------- */
.contact { border-top: 1px solid var(--rule); padding: 100px 0 0; text-align: center; }
.contact__inner { display: flex; flex-direction: column; align-items: center; }
.contact .hairline-brand { margin: 0 auto 30px; }
.contact__title {
  margin: 0 0 16px; font-family: var(--font-display); font-weight: 500;
  font-size: clamp(30px, 3.6vw, 42px); letter-spacing: -0.02em;
}
.contact__email {
  font-family: var(--font-ui); font-size: 17px; color: var(--ink);
  border-bottom: 1px solid var(--rule); padding-bottom: 3px;
  transition: border-color 0.16s ease;
}
.contact__email:hover { border-color: var(--ink); }
.contact__qr { margin: 52px 0 0; display: flex; flex-direction: column; align-items: center; gap: 14px; }
.contact__qr img {
  width: min(280px, 76vw); height: auto; border-radius: 24px;
  border: 1px solid var(--rule); background: var(--card); padding: 14px;
  image-rendering: -webkit-optimize-contrast;
}
.contact__foot { margin-top: 66px; padding: 28px 0; border-top: 1px solid var(--rule-soft); }
.contact__rights { margin: 0; font-family: var(--font-ui); font-size: 13px; color: var(--ink-faint); }
.contact__icp {
  display: inline-block; margin-top: 8px;
  font-family: var(--font-ui); font-size: 12px; color: var(--ink-faint);
  transition: color 0.16s ease;
}
.contact__icp:hover { color: var(--ink-soft); }

/* ---------- 响应式 ---------- */
@media (max-width: 860px) {
  .feature, .creed, .details, .download { padding: 84px 0; }
  .row { padding: 60px 0; }
  .row__grid { grid-template-columns: 1fr; gap: 28px; }
  .row__media, .row--reverse .row__media { order: -1; }
  .row__text p { max-width: none; }
  .details__grid { grid-template-columns: 1fr; }
  .details__item { border-left: none; border-top: 1px solid var(--rule-soft); padding: 28px 0; }
  .details__item:first-child { border-top: none; padding-top: 0; }
}

@media (max-width: 560px) {
  body { font-size: 16px; }
  .hero { padding-top: 92px; }
  .hero__shot { margin-top: 48px; }
  .hero__cta .btn { width: 100%; }
  .dl-row { flex-direction: column; align-items: stretch; }
  .dl-btn { width: 100%; }
  .controls { top: 12px; right: 12px; }
}