/* HeroShot 官网：首页固定深色（和 App 一样的近黑底 #0A0A0C + 白字 + 关键帧绿），
   协议和帮助页跟随系统浅色 / 深色，方便长时间阅读。 */

:root {
  --bg: #ffffff;
  --text: #1d1d1f;
  --dim: #5e5e63;
  --faint: #86868b;
  --line: #e5e5ea;
  --box: #f5f5f7;
  --link: #0066cc;
  --key: #4f7a12;
  --header-bg: rgba(255, 255, 255, 0.82);
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0a0a0c;
    --text: #f3f3f5;
    --dim: rgba(255, 255, 255, 0.64);
    --faint: rgba(255, 255, 255, 0.42);
    --line: rgba(255, 255, 255, 0.1);
    --box: #141417;
    --link: #8ab4ff;
    --key: #bcf25b;
    --header-bg: rgba(10, 10, 12, 0.78);
    color-scheme: dark;
  }
}
html.home {
  --bg: #0a0a0c;
  --text: #f3f3f5;
  --dim: rgba(255, 255, 255, 0.64);
  --faint: rgba(255, 255, 255, 0.42);
  --line: rgba(255, 255, 255, 0.08);
  --box: #121215;
  --link: #ffffff;
  --key: #bcf25b;
  --header-bg: rgba(10, 10, 12, 0.72);
  color-scheme: dark;
}

/* 中英文写在同一页，<html data-lang> 决定显示哪一种（见各页 <head> 里的小脚本） */
html[data-lang="zh"] [lang="en"],
html:not([data-lang="zh"]) [lang="zh-Hans"] { display: none !important; }

* { box-sizing: border-box; }
html { background: var(--bg); -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }
img, video { max-width: 100%; }
:focus-visible { outline: 2px solid var(--key); outline-offset: 3px; border-radius: 6px; }

/* ---------- 顶栏 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 10;
  background: var(--header-bg);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--line);
}
.site-header .inner {
  max-width: 1080px; margin: 0 auto; padding: 0 16px; height: 56px;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.brand {
  display: inline-flex; align-items: center; gap: 10px;
  color: var(--text); font-size: 19px; line-height: 1; letter-spacing: -0.01em;
}
.brand:hover { text-decoration: none; }
.brand img { width: 28px; height: 28px; display: block; border-radius: 22.37%; box-shadow: 0 0 0 1px var(--line); }
.wordmark { font-weight: 300; }
.wordmark b { font-weight: 700; }
.site-nav { display: flex; align-items: center; gap: 18px; font-size: 14px; }
.site-nav a { color: var(--dim); }
.site-nav a:hover { color: var(--text); text-decoration: none; }
.lang-toggle {
  font: inherit; font-size: 13px; line-height: 1; color: var(--text);
  background: transparent; border: 1px solid var(--line); border-radius: 999px;
  padding: 7px 12px; cursor: pointer;
}
.lang-toggle:hover { border-color: var(--faint); }

/* ---------- 首页 ---------- */
.hero { max-width: 1080px; margin: 0 auto; padding: 88px 16px 0; text-align: center; }
.hero h1 {
  margin: 0; font-size: clamp(40px, 7.4vw, 78px); line-height: 1.06;
  letter-spacing: -0.035em; font-weight: 700;
}
html[data-lang="zh"] .hero h1 { letter-spacing: -0.01em; line-height: 1.15; }
h1, h2, .lede, .caption { text-wrap: balance; }
/* 中文标题只在逗号处换行，不把词拆开 */
.clause { display: inline-block; }
.lede {
  max-width: 34em; margin: 22px auto 0; color: var(--dim);
  font-size: clamp(17px, 2.1vw, 21px); line-height: 1.55;
}
.availability {
  display: inline-flex; align-items: center; gap: 10px; margin-top: 34px;
  padding: 12px 22px; border-radius: 999px; border: 1px solid var(--line);
  background: var(--box); font-size: 16px; font-weight: 600;
}
.availability::before {
  content: ""; width: 8px; height: 8px; border-radius: 50%;
  background: var(--key); box-shadow: 0 0 12px var(--key);
}
.requirement { margin: 14px 0 0; font-size: 13px; color: var(--faint); }
/* 演示视频自带近黑底和暗角：四边淡出，和页面底色融成一片，看不出方框 */
.showcase, .feature video {
  -webkit-mask-image: linear-gradient(to right, transparent, #000 9%, #000 91%, transparent),
                      linear-gradient(to bottom, transparent, #000 9%, #000 91%, transparent);
  -webkit-mask-composite: source-in;
  mask-image: linear-gradient(to right, transparent, #000 9%, #000 91%, transparent),
              linear-gradient(to bottom, transparent, #000 9%, #000 91%, transparent);
  mask-composite: intersect;
}
.showcase {
  display: block; width: 100%; max-width: 1000px; height: auto;
  aspect-ratio: 1170 / 810; margin: 40px auto 0; background: #0a0a0c;
}
.caption { margin: 4px auto 0; font-size: 14px; color: var(--faint); }

.feature {
  max-width: 1080px; margin: 0 auto; padding: 128px 16px 0;
  display: grid; grid-template-columns: 1fr; gap: 28px; align-items: center;
}
@media (min-width: 880px) {
  .feature { grid-template-columns: 5fr 7fr; gap: 56px; }
  .feature.flip { grid-template-columns: 7fr 5fr; }
  .feature.flip .feature-text { order: 2; }
}
.eyebrow { margin: 0 0 12px; font-size: 14px; font-weight: 600; color: var(--key); letter-spacing: 0.02em; }
.feature h2, .section-title {
  margin: 0; font-size: clamp(28px, 4.2vw, 44px); line-height: 1.12; letter-spacing: -0.025em;
}
html[data-lang="zh"] .feature h2, html[data-lang="zh"] .section-title { letter-spacing: 0; line-height: 1.25; }
.feature-text p:not(.eyebrow) { margin: 16px 0 0; color: var(--dim); font-size: 17px; }
.feature video { display: block; width: 100%; height: auto; aspect-ratio: 1170 / 810; background: #0a0a0c; }

.more { max-width: 1080px; margin: 0 auto; padding: 144px 16px 0; }
.section-title { text-align: center; }
.grid { display: grid; gap: 14px; margin-top: 48px; grid-template-columns: 1fr; }
@media (min-width: 560px) { .grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 960px) { .grid { grid-template-columns: repeat(4, 1fr); } }
.card { background: var(--box); border: 1px solid var(--line); border-radius: 20px; padding: 22px 22px 24px; }
.card svg { width: 26px; height: 26px; color: var(--text); display: block; margin-bottom: 16px; }
.card h3 { margin: 0 0 6px; font-size: 17px; letter-spacing: -0.01em; }
.card p { margin: 0; font-size: 15px; line-height: 1.55; color: var(--dim); }

.bands {
  max-width: 1080px; margin: 0 auto; padding: 144px 16px 0;
  display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(min(100%, 380px), 1fr));
}
.band { background: var(--box); border: 1px solid var(--line); border-radius: 28px; padding: 44px 32px; }
.band h2 { margin: 0; font-size: clamp(24px, 3vw, 32px); line-height: 1.2; letter-spacing: -0.02em; }
html[data-lang="zh"] .band h2 { letter-spacing: 0; }
.band p { margin: 14px 0 0; color: var(--dim); font-size: 16px; }
.band .more-link { display: inline-block; margin-top: 18px; font-size: 15px; font-weight: 600; }

/* ---------- 协议 / 帮助 ---------- */
.doc { max-width: 720px; margin: 0 auto; padding: 48px 16px 0; }
.doc-tabs { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 36px; font-size: 14px; }
.doc-tabs a {
  padding: 6px 12px; border-radius: 999px; border: 1px solid var(--line); color: var(--dim);
}
.doc-tabs a:hover { color: var(--text); text-decoration: none; }
.doc-tabs a[aria-current="page"] { background: var(--text); border-color: var(--text); color: var(--bg); }
.doc h1 { margin: 0 0 8px; font-size: clamp(30px, 5vw, 40px); line-height: 1.15; letter-spacing: -0.02em; }
.doc .date { margin: 0 0 28px; color: var(--faint); font-size: 15px; }
.doc h2 { margin: 40px 0 10px; font-size: 20px; line-height: 1.35; letter-spacing: -0.01em; }
.doc h3 { margin: 24px 0 8px; font-size: 17px; }
.doc p, .doc li { margin: 0 0 12px; font-size: 16px; line-height: 1.7; }
.doc ul, .doc ol { padding-left: 22px; margin: 0 0 12px; }
.doc .notice, .doc .summary {
  background: var(--box); border: 1px solid var(--line); border-radius: 14px;
  padding: 16px 20px; margin: 24px 0;
}
.doc .notice p:last-child, .doc .summary p:last-child { margin-bottom: 0; }

.contact-card {
  background: var(--box); border: 1px solid var(--line); border-radius: 18px;
  padding: 22px 24px; margin: 8px 0 40px;
}
.contact-card .mail { display: inline-block; margin: 4px 0 8px; font-size: 22px; font-weight: 600; }
.contact-card p { margin: 0; color: var(--dim); font-size: 15px; }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary {
  cursor: pointer; list-style: none; padding: 16px 32px 16px 0; position: relative;
  font-size: 17px; font-weight: 600; line-height: 1.45;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; position: absolute; right: 4px; top: 13px; font-size: 22px; font-weight: 300; color: var(--faint);
}
.faq details[open] summary::after { content: "−"; }
.faq details > div { padding: 0 0 14px; }
.faq details p, .faq details li { color: var(--dim); }

.not-found { max-width: 720px; margin: 0 auto; padding: 120px 16px 0; text-align: center; }
.not-found h1 { margin: 0; font-size: clamp(30px, 5vw, 40px); }
.not-found p { color: var(--dim); }

/* ---------- 页脚 ---------- */
.site-footer { margin-top: 128px; border-top: 1px solid var(--line); }
.site-footer .inner {
  max-width: 1080px; margin: 0 auto; padding: 28px 16px 44px;
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 16px 32px;
  font-size: 13px; color: var(--dim);
}
.site-footer .brand { font-size: 16px; }
.site-footer .brand img { width: 22px; height: 22px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 8px 20px; }
.footer-links a { color: var(--dim); }
.footer-links a:hover { color: var(--text); }
.legal-note { width: 100%; margin: 0; font-size: 12px; line-height: 1.6; color: var(--faint); }

@media (max-width: 520px) {
  .site-nav { gap: 12px; }
  .hero { padding-top: 56px; }
  .feature { padding-top: 96px; }
  .more, .bands { padding-top: 104px; }
  .band { padding: 32px 22px; }
  .site-footer { margin-top: 96px; }
}