/* ============================================================
   PicView中文站 样式表
   主色取自 PicView 官方 Logo（#e95a27）
   设计：扁平现代 / 浅色 / 留白充足 / 系统字体栈 / 无外部依赖
   ============================================================ */

:root {
  --brand: #e95a27;          /* 官方 Logo 主色 */
  --brand-strong: #c9481a;   /* 主色深阶（悬停） */
  --brand-soft: #fdeee6;     /* 主色浅底 */
  --brand-accent: #f8af3c;   /* Logo 辅助黄 */
  --ink: #22262e;            /* 主文字 */
  --ink-soft: #5a6270;       /* 次级文字 */
  --line: #e6e9ef;           /* 分隔线 */
  --bg: #ffffff;
  --bg-soft: #f6f7fa;
  --radius: 14px;
  --shadow: 0 6px 24px rgba(34, 38, 46, .08);
  --shadow-lg: 0 16px 48px rgba(34, 38, 46, .16);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --maxw: 1080px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- 可访问性 ---------- */
.visually-hidden {
  position: absolute; width: 1px; height: 1px;
  margin: -1px; padding: 0; border: 0;
  clip: rect(0 0 0 0); clip-path: inset(50%);
  overflow: hidden; white-space: nowrap;
}
.skip-link {
  position: absolute; left: 16px; top: -60px;
  background: var(--brand); color: #fff;
  padding: 10px 18px; border-radius: 0 0 10px 10px;
  z-index: 100; font-weight: 600; transition: top .2s;
}
.skip-link:focus { top: 0; text-decoration: none; }

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

/* ---------- 头部 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px; gap: 24px;
}
.brand img { width: 120px; }
.site-nav ul { display: flex; gap: 6px; list-style: none; }
.site-nav a {
  display: inline-flex; align-items: center;
  min-height: 44px; padding: 0 14px;
  color: var(--ink-soft); font-weight: 500; border-radius: 8px;
  transition: color .2s, background .2s;
}
.site-nav a:hover { color: var(--brand); text-decoration: none; background: var(--brand-soft); }
.site-nav a[aria-current="page"] { color: var(--brand); font-weight: 700; }

.nav-toggle {
  display: none; align-items: center; justify-content: center;
  width: 44px; height: 44px;
  background: none; border: none; color: var(--ink); cursor: pointer;
  border-radius: 8px;
}

@media (max-width: 860px) {
  .nav-toggle { display: inline-flex; }
  .site-nav {
    position: absolute; top: 64px; left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--line);
    display: none; box-shadow: var(--shadow);
  }
  .site-nav.open { display: block; }
  .site-nav ul { flex-direction: column; padding: 8px 16px 16px; }
}

/* ---------- 英雄区 ---------- */
.hero {
  padding: 88px 0 72px;
  background:
    radial-gradient(720px 360px at 88% -10%, var(--brand-soft), transparent 70%),
    radial-gradient(520px 300px at -8% 108%, #fdf6e9, transparent 70%),
    var(--bg);
  overflow: hidden;
}
.hero-inner {
  display: grid; grid-template-columns: 1.05fr .95fr;
  gap: 56px; align-items: center;
}
.eyebrow {
  display: inline-block;
  font-size: 13px; font-weight: 700; letter-spacing: .12em;
  color: var(--brand); text-transform: uppercase;
  background: var(--brand-soft);
  border: 1px solid #f6d4c2;
  padding: 5px 14px; border-radius: 999px; margin-bottom: 18px;
}
.hero-copy h1 {
  font-size: clamp(30px, 4.4vw, 46px);
  line-height: 1.25; letter-spacing: -.01em; margin-bottom: 18px;
}
.lead { color: var(--ink-soft); font-size: 17px; margin-bottom: 28px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-bottom: 18px; }
.hero-meta { font-size: 14px; color: var(--ink-soft); }
.hero-meta strong { color: var(--ink); }

.hero-img {
  display: block; width: 100%; height: auto;
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--line);
  transition: transform .5s cubic-bezier(.2, .8, .2, 1);
}
.hero-frame:hover .hero-img, .hero-fig:hover .hero-img { transform: scale(1.015); }
.hero-cap { font-size: 13px; color: var(--ink-soft); margin-top: 12px; text-align: center; }

@media (max-width: 900px) {
  .hero { padding: 56px 0 48px; }
  .hero-inner { grid-template-columns: 1fr; gap: 36px; }
  .hero-frame { transform: none; }
  .hero-fig:hover .hero-img { transform: none; }
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 48px; padding: 0 26px;
  border-radius: 10px; font-size: 16px; font-weight: 600;
  border: 1px solid transparent; cursor: pointer;
  transition: transform .15s, box-shadow .2s, background .2s, color .2s, border-color .2s;
}
.btn:active { transform: translateY(1px); }
.btn-primary {
  background: linear-gradient(135deg, var(--brand), #f07a3d);
  color: #fff; box-shadow: 0 6px 18px rgba(233, 90, 39, .35);
}
.btn-primary:hover { background: linear-gradient(135deg, var(--brand-strong), var(--brand)); box-shadow: 0 8px 24px rgba(233, 90, 39, .45); }
.btn-ghost {
  background: #fff; color: var(--ink);
  border-color: var(--line);
}
.btn-ghost:hover { border-color: var(--brand); color: var(--brand); }
.btn-download {
  background: linear-gradient(135deg, var(--brand), #f07a3d);
  color: #fff; box-shadow: 0 6px 18px rgba(233, 90, 39, .35);
}
.btn-download:hover { background: linear-gradient(135deg, var(--brand-strong), var(--brand)); }

/* ---------- 区块 ---------- */
.section { padding: 72px 0; }
.section-alt { background: var(--bg-soft); }
.section-title { font-size: clamp(24px, 3vw, 32px); margin-bottom: 40px; text-align: center; }
.section-sub { text-align: center; color: var(--ink-soft); max-width: 720px; margin: -24px auto 40px; }

/* 卡片网格 */
.grid { display: grid; gap: 22px; }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
@media (max-width: 980px) { .grid-4 { grid-template-columns: repeat(2, 1fr); } .grid-3 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 620px) { .grid-4, .grid-3, .grid-2 { grid-template-columns: 1fr; } }

.card {
  background: #fff; border: 1px solid var(--line);
  border-radius: var(--radius); padding: 26px;
  transition: transform .25s, box-shadow .25s, border-color .25s;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: #f0c9b6; }
.card-icon {
  width: 52px; height: 52px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  background: var(--brand-soft); color: var(--brand); margin-bottom: 16px;
}
.card h3 { font-size: 18px; margin-bottom: 8px; }
.card p { color: var(--ink-soft); font-size: 15px; }

/* ---------- 数据条 ---------- */
.stat-row {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; margin-bottom: 20px;
}
.stat {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 18px; text-align: center;
}
.stat strong { display: block; font-size: 30px; color: var(--brand); letter-spacing: -.02em; }
.stat span { font-size: 14px; color: var(--ink-soft); }
@media (max-width: 720px) { .stat-row { grid-template-columns: repeat(2, 1fr); } }
.stat-note { font-size: 13px; color: var(--ink-soft); text-align: center; margin-bottom: 44px; }

/* ---------- CTA 横带 ---------- */
.cta-band {
  display: flex; align-items: center; justify-content: space-between; gap: 24px;
  background: linear-gradient(120deg, #262a33, #3a3f4b);
  border-radius: var(--radius); padding: 34px 40px; color: #fff;
  flex-wrap: wrap;
}
.cta-band h3 { font-size: 22px; margin-bottom: 6px; }
.cta-band p { color: #c6ccd8; font-size: 15px; }

/* ---------- 页头横幅（内页） ---------- */
.page-hero {
  padding: 64px 0 48px;
  background:
    radial-gradient(640px 300px at 90% -20%, var(--brand-soft), transparent 70%),
    var(--bg);
  border-bottom: 1px solid var(--line);
}
.page-hero h1 { font-size: clamp(28px, 4vw, 40px); margin-bottom: 12px; }
.page-hero .lead { max-width: 760px; margin-bottom: 0; }

/* ---------- 面包屑 ---------- */
.breadcrumb { margin-bottom: 14px; }
.breadcrumb ol {
  list-style: none; display: flex; flex-wrap: wrap;
  gap: 4px 0; font-size: 13px; color: var(--ink-soft);
}
.breadcrumb li { display: flex; align-items: center; }
.breadcrumb li + li::before {
  content: "/"; margin: 0 8px; color: #c3c9d4;
}
.breadcrumb a {
  color: var(--ink-soft); display: inline-flex; align-items: center;
  min-height: 24px; padding: 0 2px;
}
.breadcrumb a:hover { color: var(--brand); }
.breadcrumb [aria-current="page"] { color: var(--ink); font-weight: 600; }

/* ---------- 功能分组 ---------- */
.feature-group { margin-bottom: 56px; }
.feature-group h2 {
  display: flex; align-items: center; gap: 12px;
  font-size: 24px; margin-bottom: 22px;
}
.feature-group h2 .chip {
  font-size: 12px; font-weight: 700; color: var(--brand);
  background: var(--brand-soft); border: 1px solid #f6d4c2;
  padding: 3px 10px; border-radius: 999px; letter-spacing: .06em;
}

/* ---------- 表格 ---------- */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
table { width: 100%; border-collapse: collapse; font-size: 15px; min-width: 560px; }
thead th {
  text-align: left; background: var(--bg-soft);
  padding: 13px 18px; font-size: 13px; letter-spacing: .08em;
  color: var(--ink-soft); border-bottom: 1px solid var(--line); white-space: nowrap;
}
tbody td { padding: 13px 18px; border-bottom: 1px solid var(--line); vertical-align: top; }
tbody tr:last-child td { border-bottom: none; }
tbody tr:hover { background: #fbfaf8; }
td kbd, .kbd {
  display: inline-block; font-family: ui-monospace, "SF Mono", Consolas, monospace;
  background: var(--bg-soft); border: 1px solid var(--line); border-bottom-width: 2px;
  border-radius: 6px; padding: 1px 8px; font-size: 13px; white-space: nowrap;
}

/* ---------- 术语/步骤 ---------- */
.steps { counter-reset: step; display: grid; gap: 16px; max-width: 760px; }
.step {
  display: flex; gap: 18px; align-items: flex-start;
  background: #fff; border: 1px solid var(--line);
  border-radius: var(--radius); padding: 20px 24px;
}
.step::before {
  counter-increment: step;
  content: counter(step);
  flex: 0 0 auto;
  width: 36px; height: 36px; border-radius: 50%;
  background: var(--brand); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 16px; margin-top: 2px;
}
.step h3 { font-size: 16px; margin-bottom: 4px; }
.step p { color: var(--ink-soft); font-size: 15px; }

/* ---------- FAQ ---------- */
.faq-list { display: grid; gap: 14px; max-width: 820px; margin: 0 auto; }
details.faq {
  background: #fff; border: 1px solid var(--line);
  border-radius: 12px; padding: 0 22px;
  transition: border-color .2s;
}
details.faq[open] { border-color: #f0c9b6; box-shadow: var(--shadow); }
details.faq summary {
  cursor: pointer; list-style: none;
  font-weight: 600; font-size: 16px;
  padding: 17px 0; min-height: 44px;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
details.faq summary::-webkit-details-marker { display: none; }
details.faq summary::after {
  content: ""; width: 10px; height: 10px; flex: 0 0 auto;
  border-right: 2.5px solid var(--brand); border-bottom: 2.5px solid var(--brand);
  transform: rotate(45deg); transition: transform .25s; margin-top: -4px;
}
details.faq[open] summary::after { transform: rotate(225deg); margin-top: 4px; }
details.faq .faq-a { padding: 0 0 18px; color: var(--ink-soft); font-size: 15px; }
details.faq .faq-a a { word-break: break-all; }

/* ---------- 下载卡片 ---------- */
.dl-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
@media (max-width: 980px) { .dl-grid { grid-template-columns: 1fr; } }
.dl-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px; display: flex; flex-direction: column;
  transition: transform .25s, box-shadow .25s;
}
.dl-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.dl-card h3 { font-size: 19px; margin-bottom: 6px; display: flex; align-items: center; gap: 10px; }
.dl-card .dl-meta { color: var(--ink-soft); font-size: 14px; margin-bottom: 18px; flex: 1; }
.dl-card .dl-meta li { margin-left: 18px; margin-bottom: 2px; }
.os-icon { color: var(--brand); display: inline-flex; }
.dl-badges { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }
.badge {
  font-size: 12px; font-weight: 600; letter-spacing: .04em;
  background: var(--bg-soft); border: 1px solid var(--line);
  color: var(--ink-soft); border-radius: 999px; padding: 4px 12px;
}

/* ---------- 404 ---------- */
.nf-wrap { text-align: center; padding: 110px 24px 130px; }
.nf-code {
  font-size: clamp(90px, 16vw, 150px); font-weight: 800; line-height: 1;
  letter-spacing: -.04em; color: var(--brand); opacity: .92;
}
.nf-wrap h1 { font-size: 26px; margin: 10px 0 12px; }
.nf-wrap p { color: var(--ink-soft); margin-bottom: 30px; }

/* ---------- 页脚 ---------- */
.site-footer { background: #1e222a; color: #b9c0cc; margin-top: 0; }
.footer-grid {
  display: grid; grid-template-columns: 1.2fr 2fr; gap: 48px;
  padding: 56px 24px 40px;
}
.footer-brand img { margin-bottom: 16px; }
.footer-brand p { font-size: 14px; color: #8d95a3; max-width: 380px; }
.footer-nav { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.footer-nav h4 {
  color: #e7eaf0; font-size: 14px; letter-spacing: .08em;
  margin-bottom: 14px; font-weight: 700;
}
.footer-nav ul { list-style: none; }
.footer-nav li { margin-bottom: 8px; }
.footer-nav a { color: #b9c0cc; font-size: 14px; }
.footer-nav a:hover { color: #fff; }
.link-btn {
  background: none; border: none; padding: 0;
  color: #f2986d; font-size: 14px; cursor: pointer; font-family: inherit;
  min-height: 24px;
}
.link-btn:hover { color: #ffb48f; text-decoration: underline; }
.footer-bottom { border-top: 1px solid #31363f; padding: 20px 24px; }
.footer-bottom p { font-size: 13px; color: #78808e; text-align: center; }
@media (max-width: 860px) {
  .footer-grid { grid-template-columns: 1fr; gap: 36px; }
  .footer-nav { grid-template-columns: repeat(2, 1fr); }
}

/* ---------- 弹窗 ---------- */
.modal-overlay {
  position: fixed; inset: 0; z-index: 90;
  background: rgba(24, 27, 33, .58);
  display: flex; align-items: center; justify-content: center;
  padding: 24px;
  opacity: 0; pointer-events: none;
  transition: opacity .25s;
}
.modal-overlay.open { opacity: 1; pointer-events: auto; }
.modal {
  position: relative;
  background: #fff; border-radius: 18px;
  max-width: 560px; width: 100%;
  padding: 36px 32px 30px;
  box-shadow: var(--shadow-lg);
  transform: translateY(14px) scale(.97);
  transition: transform .3s cubic-bezier(.2, .8, .2, 1);
}
.modal-overlay.open .modal { transform: translateY(0) scale(1); }
.modal-close {
  position: absolute; top: 14px; right: 14px;
  width: 44px; height: 44px;
  display: flex; align-items: center; justify-content: center;
  background: var(--bg-soft); border: none; border-radius: 50%;
  color: var(--ink); cursor: pointer; transition: background .2s;
}
.modal-close:hover { background: #f3d9cb; }
.modal-title { font-size: 22px; margin-bottom: 6px; }
.modal-desc { color: var(--ink-soft); font-size: 15px; margin-bottom: 26px; }
.qr-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.qr-box { text-align: center; }
.qr-img {
  width: 180px; height: 180px; margin: 0 auto 12px;
  padding: 8px; box-sizing: border-box;
  display: block;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
}
.qr-box p { font-size: 14px; color: var(--ink); font-weight: 600; }
.modal-note { font-size: 13px; color: var(--ink-soft); margin-top: 24px; text-align: center; }
@media (max-width: 520px) {
  .qr-row { grid-template-columns: 1fr; }
  .qr-img { width: 150px; height: 150px; }
  .modal { padding: 28px 20px 24px; }
}

/* ---------- 滚动显现动画 ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .6s ease, transform .6s ease; }
.reveal.visible { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
  .hero-frame, .card, .dl-card { transition: none; }
}