/* ============ 筛片大师官网 · 现代浅色 SaaS 风 ============
   自家路线：靛蓝紫主色 + 薄雾蓝渐变首屏 + 大圆角软阴影卡片。 */

:root {
  --brand: #4f46e5;
  --brand-deep: #4338ca;
  --brand-soft: #ecebfc;
  --ink: #16182e;
  --text: #3d4159;
  --muted: #72768f;
  --line: #e5e6f2;
  --bg: #ffffff;
  --bg-alt: #f7f7fc;
  --dark: #131529;
  --red: #e8590c;
  --radius: 18px;
  --shadow: 0 10px 30px -12px rgba(22, 24, 46, .12);
  --shadow-lg: 0 30px 80px -30px rgba(22, 24, 46, .28);
  --sans: "PingFang SC", "MiSans", "Microsoft YaHei", "Noto Sans SC", system-ui, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: var(--sans); color: var(--text); background: var(--bg); line-height: 1.75; -webkit-font-smoothing: antialiased; }
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
.wrap { max-width: 1160px; margin: 0 auto; padding: 0 24px; }
.wrap-narrow { max-width: 820px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 32px; border-radius: 999px; font-size: 15.5px; font-weight: 600;
  border: 1.5px solid transparent; transition: .18s; cursor: pointer; white-space: nowrap;
}
.btn-primary { background: var(--brand); color: #fff; box-shadow: 0 8px 20px -8px rgba(79, 70, 229, .5); }
.btn-primary:hover { background: var(--brand-deep); transform: translateY(-1px); }
.btn-line { background: #fff; color: var(--ink); border-color: var(--line); box-shadow: var(--shadow); }
.btn-line:hover { border-color: var(--brand); color: var(--brand); }
.btn-white { background: #fff; color: var(--brand-deep); }
.btn-white:hover { transform: translateY(-2px); box-shadow: 0 14px 30px -12px rgba(0,0,0,.35); }
.btn-sm { padding: 8px 22px; font-size: 14px; }
.btn-block { width: 100%; }

/* ---------- 顶栏 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 60;
  background: rgba(255,255,255,.85); backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.header-in { display: flex; align-items: center; justify-content: space-between; height: 66px; gap: 24px; }
.brand { display: flex; align-items: center; gap: 10px; }
.brand-mark {
  width: 34px; height: 34px; display: grid; place-items: center; border-radius: 10px;
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  color: #fff; font-size: 17px; font-weight: 800;
}
.brand-name { font-size: 19px; font-weight: 800; color: var(--ink); letter-spacing: .5px; }
.nav { display: flex; gap: 30px; font-size: 14.5px; }
.nav a { color: var(--muted); transition: .15s; }
.nav a:hover { color: var(--brand); }

/* ---------- 首屏 ---------- */
.hero {
  text-align: center;
  padding: 72px 0 0;
  background:
    radial-gradient(60% 45% at 50% 0%, rgba(129, 140, 248, .18), transparent 70%),
    linear-gradient(#f4f4fd, #fff 62%);
}
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 7px 18px; border-radius: 999px; background: var(--brand-soft);
  color: var(--brand-deep); font-size: 13.5px; font-weight: 600; letter-spacing: 1px;
}
.hero-badge .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--brand); }
.hero-title { margin: 22px 0 18px; font-size: clamp(34px, 5.6vw, 58px); font-weight: 900; color: var(--ink); letter-spacing: 2px; line-height: 1.25; }
.hero-title em { font-style: normal; color: var(--brand); }
.hero-desc { color: var(--muted); font-size: 16.5px; max-width: 640px; margin: 0 auto 34px; }
.pc-br { display: inline; }
.hero-act { display: flex; justify-content: center; gap: 16px; }
.hero-stats {
  list-style: none; display: flex; justify-content: center; gap: clamp(28px, 6vw, 76px);
  margin: 44px auto 52px;
}
.hero-stats b { display: block; font-size: clamp(26px, 3.4vw, 36px); font-weight: 900; color: var(--ink); line-height: 1.25; }
.hero-stats span { font-size: 13px; color: var(--muted); }
.hero-shot { position: relative; max-width: 980px; margin: 0 auto; padding: 0 24px 64px; }
.hero-chip {
  position: absolute; left: 56px; bottom: 88px;
  background: rgba(19, 21, 41, .85); color: #a5b4fc; border: 1px solid rgba(165, 180, 252, .35);
  font-size: 12.5px; padding: 6px 14px; border-radius: 8px; backdrop-filter: blur(4px);
}

/* 深色窗口框 */
.window {
  background: var(--dark); border-radius: var(--radius); overflow: hidden;
  box-shadow: var(--shadow-lg); border: 1px solid #262a4a;
}
.window-bar {
  display: flex; align-items: center; gap: 7px; height: 38px; padding: 0 14px;
  color: #8c90b3; font-size: 12.5px;
}
.window-bar span { margin-left: 10px; }
.d { width: 11px; height: 11px; border-radius: 50%; }
.d.r { background: #ff5f57; } .d.y { background: #febc2e; } .d.g { background: #28c840; }
.window img { border-top: 1px solid #2a2e52; }

/* ---------- 通用 section ---------- */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.sec-kicker { text-align: center; color: var(--brand); font-size: 13px; font-weight: 700; letter-spacing: 3px; text-transform: uppercase; margin-bottom: 10px; }
.sec-title { text-align: center; font-size: clamp(26px, 3.4vw, 38px); font-weight: 900; color: var(--ink); letter-spacing: 1px; margin-bottom: 14px; }
.sec-sub { text-align: center; color: var(--muted); font-size: 15.5px; max-width: 620px; margin: 0 auto 56px; }

/* ---------- 功能卡片 ---------- */
.feat-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px 28px; box-shadow: var(--shadow); transition: .2s;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: rgba(79,70,229,.35); }
.card h3 { font-size: 17.5px; color: var(--ink); margin: 18px 0 10px; letter-spacing: .5px; }
.card p { font-size: 14.5px; color: var(--muted); }
.ic { width: 46px; height: 46px; border-radius: 13px; display: grid; place-items: center; }
.ic svg { width: 23px; height: 23px; }
.ic-green { background: #ecebfc; fill: #4f46e5; }
.ic-red { background: #fdeee5; fill: #e8590c; }
.ic-orange { background: #fff4e0; fill: #f08c00; }
.ic-blue { background: #e7f1fd; fill: #1c7ed6; }
.ic-purple { background: #f1ecfd; fill: #7048e8; }
.ic-teal { background: #e3f6f8; fill: #0b7285; }

/* ---------- 界面一览 ---------- */
.screen-row {
  display: grid; grid-template-columns: 1.35fr 1fr; gap: 48px; align-items: center;
  margin-bottom: 72px;
}
.screen-row.flip .screen-win { order: 2; }
.screen-row.flip .screen-desc { order: 1; }
.screen-row:last-child { margin-bottom: 0; }
.screen-desc h3 { font-size: 24px; color: var(--ink); font-weight: 800; margin-bottom: 14px; letter-spacing: .5px; }
.screen-desc > p { color: var(--muted); font-size: 15px; margin-bottom: 18px; }
.ticks { list-style: none; }
.ticks li { position: relative; padding-left: 28px; font-size: 14.5px; color: var(--text); margin-bottom: 10px; }
.ticks li::before {
  content: ""; position: absolute; left: 0; top: 5px; width: 16px; height: 16px;
  background: var(--brand-soft) url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="%234f46e5"><path d="M9.5 16.2 5.3 12l1.4-1.4 2.8 2.8 7.8-7.8L18.7 7z"/></svg>') center/11px no-repeat;
  border-radius: 50%;
}

/* ---------- 步骤条 ---------- */
.steps { list-style: none; display: grid; grid-template-columns: repeat(4, 1fr); gap: 26px; position: relative; counter-reset: s; }
.steps::before { content: ""; position: absolute; top: 26px; left: 12%; right: 12%; height: 2px; background: linear-gradient(90deg, var(--brand-soft), var(--brand), var(--brand-soft)); }
.steps li { position: relative; text-align: center; padding-top: 0; }
.step-no {
  display: inline-grid; place-items: center; width: 52px; height: 52px; border-radius: 50%;
  background: #fff; border: 2px solid var(--brand); color: var(--brand);
  font-size: 20px; font-weight: 800; margin-bottom: 16px; position: relative; z-index: 1;
}
.steps h4 { font-size: 17px; color: var(--ink); margin-bottom: 8px; }
.steps p { font-size: 13.5px; color: var(--muted); max-width: 220px; margin: 0 auto; }

/* ---------- 下载 ---------- */
.dl-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; max-width: 980px; margin: 0 auto; }
.dl-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 34px 28px; text-align: center; box-shadow: var(--shadow); transition: .2s;
}
.dl-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.dl-ic { width: 52px; height: 52px; margin: 0 auto 14px; border-radius: 14px; background: var(--brand-soft); display: grid; place-items: center; }
.dl-ic svg { width: 26px; height: 26px; fill: var(--brand-deep); }
.dl-card h3 { font-size: 18px; color: var(--ink); margin-bottom: 4px; }
.dl-meta { font-size: 13px; color: var(--muted); margin-bottom: 20px; }
.dl-note { font-size: 12.5px; color: var(--muted); margin-top: 12px; }
.dl-tip { text-align: center; margin-top: 36px; font-size: 14px; color: var(--muted); }
.dl-tip em { font-style: normal; color: var(--brand-deep); font-weight: 600; }
.dl-tip a { color: var(--brand); border-bottom: 1px dashed var(--brand); }

/* ---------- FAQ ---------- */
.faq-list { display: flex; flex-direction: column; gap: 14px; }
details {
  background: #fff; border: 1px solid var(--line); border-radius: 14px;
  padding: 0 24px; transition: .2s; overflow: hidden;
}
details[open] { border-color: rgba(79,70,229,.4); box-shadow: var(--shadow); }
summary {
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  height: 60px; font-size: 15.5px; font-weight: 600; color: var(--ink); cursor: pointer; list-style: none;
}
summary::-webkit-details-marker { display: none; }
summary i { position: relative; width: 12px; height: 12px; flex: none; }
summary i::before, summary i::after {
  content: ""; position: absolute; background: var(--brand); border-radius: 2px; transition: .2s;
}
summary i::before { left: 0; top: 5px; width: 12px; height: 2px; }
summary i::after { left: 5px; top: 0; width: 2px; height: 12px; }
details[open] summary i::after { transform: rotate(90deg); opacity: 0; }
details p { padding: 0 0 22px; font-size: 14.5px; color: var(--muted); }

/* ---------- CTA ---------- */
.cta { background: linear-gradient(120deg, #4338ca, #4f46e5 55%, #8b5cf6); color: #fff; text-align: center; padding: 88px 0; }
.cta h2 { font-size: clamp(26px, 3.6vw, 40px); font-weight: 900; letter-spacing: 2px; margin-bottom: 14px; }
.cta p { opacity: .92; margin-bottom: 34px; font-size: 16px; }

/* ---------- 客服区域 ---------- */
.contact-section { background: var(--bg-alt); border-top: 1px solid var(--line); }
.contact-card {
  display: inline-block; background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 32px 48px; box-shadow: var(--shadow); text-align: center;
}
.contact-qrcode {
  width: 180px; height: 180px; border-radius: 12px; border: 1px solid var(--line);
  background: #fff; padding: 6px; object-fit: contain;
}
.contact-tip { margin-top: 14px; font-size: 14px; color: var(--muted); }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--dark); color: #a3a7c2; padding: 64px 0 0; }
.footer-grid { display: grid; grid-template-columns: 2.2fr 1fr 1fr 1fr 1fr; gap: 40px; padding-bottom: 44px; }
.footer-about .brand-name { color: #fff; }
.footer-about p { font-size: 13.5px; margin-top: 16px; max-width: 300px; line-height: 1.9; }
.footer-col h4 { color: #fff; font-size: 14.5px; margin-bottom: 16px; letter-spacing: 1px; }
.footer-col a { display: block; font-size: 13.5px; margin-bottom: 10px; transition: .15s; }
.footer-col a:hover { color: #a5b4fc; }
.copyright { border-top: 1px solid #262a4a; text-align: center; font-size: 12.5px; padding: 22px 24px; }

/* ---------- 渐入 ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .65s ease, transform .65s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- 教程页（install-macos） ---------- */
.nav a.is-active { color: var(--brand); font-weight: 600; }
.doc-hero {
  text-align: center; padding: 64px 0 44px;
  background:
    radial-gradient(60% 45% at 50% 0%, rgba(129, 140, 248, .18), transparent 70%),
    linear-gradient(#f4f4fd, #fff 70%);
}
.doc-title { margin: 20px 0 12px; font-size: clamp(30px, 4.6vw, 46px); font-weight: 900; color: var(--ink); letter-spacing: 2px; }
.doc-lead { color: var(--muted); font-size: 16px; margin-bottom: 26px; }
.doc-anchor { display: flex; justify-content: center; flex-wrap: wrap; gap: 12px; }
.doc-anchor a {
  padding: 8px 18px; border-radius: 999px; background: #fff; border: 1px solid var(--line);
  font-size: 13.5px; color: var(--text); box-shadow: var(--shadow); transition: .15s;
}
.doc-anchor a:hover { border-color: var(--brand); color: var(--brand); }
.doc-body { padding-top: 72px; }
.doc-step { position: relative; padding: 0 0 56px 76px; }
.doc-step::before { /* 步骤间竖线 */
  content: ""; position: absolute; left: 25px; top: 56px; bottom: 8px; width: 2px;
  background: linear-gradient(var(--brand), var(--brand-soft)); opacity: .35;
}
.doc-step:last-child::before { display: none; }
.doc-step:last-child { padding-bottom: 8px; }
.doc-no {
  position: absolute; left: 0; top: 0;
  width: 52px; height: 52px; border-radius: 50%; display: grid; place-items: center;
  background: #fff; border: 2px solid var(--brand); color: var(--brand);
  font-size: 22px; font-weight: 800;
}
.doc-step h2 { font-size: 24px; color: var(--ink); font-weight: 800; margin-bottom: 14px; line-height: 52px; letter-spacing: .5px; }
.doc-step > p { color: var(--text); font-size: 15px; margin-bottom: 12px; }
.doc-step strong { color: var(--ink); }
.doc-fine { font-size: 13.5px; color: var(--muted); }
.doc-step code { background: var(--brand-soft); color: var(--brand-deep); padding: 2px 8px; border-radius: 6px; font-size: 13px; }
.chip-rows { display: flex; flex-direction: column; gap: 10px; margin: 16px 0 14px; }
.chip-row { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; font-size: 14.5px; }
.chip-row b { color: var(--ink); }
.chip-arrow { color: var(--muted); }
.chip-tag { padding: 5px 14px; border-radius: 8px; background: #f1f2f8; border: 1px solid var(--line); font-size: 13.5px; color: var(--text); }
.chip-tag.chip-green { background: var(--brand-soft); border-color: rgba(79,70,229,.35); color: var(--brand-deep); font-weight: 600; }
.doc-tip {
  margin-top: 18px; padding: 18px 22px; border-radius: 14px;
  background: #fff9e8; border: 1px solid #f5e3ac;
}
.doc-tip h4 { font-size: 15px; color: #8a6100; margin-bottom: 6px; }
.doc-tip p { font-size: 14px; color: #7a6a45; }
.doc-list { padding-left: 20px; display: flex; flex-direction: column; gap: 10px; font-size: 15px; }
.doc-list li::marker { color: var(--brand); font-weight: 700; }
.doc-sub { list-style: none; padding-left: 0; margin-top: 10px; display: flex; flex-direction: column; gap: 8px; }
.doc-sub li { position: relative; padding-left: 20px; font-size: 14px; color: var(--muted); }
.doc-sub li::before { content: "–"; position: absolute; left: 4px; color: var(--brand); }
.ok-text { color: var(--brand-deep); }
.case { border-radius: 14px; padding: 20px 24px; margin: 16px 0; border: 1px solid var(--line); background: #fff; box-shadow: var(--shadow); }
.case h3 { font-size: 16.5px; color: var(--ink); margin-bottom: 8px; }
.case p { font-size: 14.5px; color: var(--muted); }
.case .doc-list { font-size: 14.5px; }
.case-ok { border-left: 4px solid var(--brand); background: #f4f4fd; }
.case-fix { border-left: 4px solid #f08c00; }
.case-last { border-left: 4px solid #ced4da; background: #fafbfb; }
@media (max-width: 560px) {
  .doc-step { padding-left: 0; }
  .doc-step::before { display: none; }
  .doc-step h2 { line-height: 1.5; margin-top: 14px; }
}

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .nav { display: none; }
  .feat-grid, .dl-grid { grid-template-columns: 1fr; max-width: 460px; margin-left: auto; margin-right: auto; }
  .screen-row, .screen-row.flip { grid-template-columns: 1fr; gap: 22px; }
  .screen-row.flip .screen-win { order: 0; }
  .steps { grid-template-columns: 1fr 1fr; }
  .steps::before { display: none; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .hero-chip { left: 36px; bottom: 84px; }
  .pc-br { display: none; }
}
@media (max-width: 560px) {
  .hero-title { font-size: clamp(24px, 7vw, 30px); letter-spacing: 1px; }
  .hero-desc { font-size: 15px; text-wrap: balance; }
  .hero-stats { flex-wrap: wrap; gap: 20px 34px; }
  .hero-act { flex-direction: column; align-items: center; }
  .steps { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .section { padding: 68px 0; }
}