/* ==========================================================================
   balenaEtcher 中文官网 — 全局样式（浅色主题）
   主色取自官方 logo：#A5DE37（亮黄绿）/ 辅助 #C8F178
   风格：明亮扁平、现代专业
   ========================================================================== */

:root {
  --brand: #A5DE37;          /* logo 主色（保持不变） */
  --brand-light: #B8E94C;    /* 高亮辅助 */
  --brand-dark: #6FA31E;     /* 深绿：文字强调 / hover */
  --brand-ink: #14211A;      /* 黄绿按钮上的深色文字 */
  --bg: #F6F8F5;             /* 页面背景：极浅灰白 */
  --bg-elevated: #FFFFFF;    /* 卡片 / 面板 */
  --bg-elevated-2: #EDF2EA;  /* 次级面板：浅灰绿 */
  --border: rgba(16, 30, 20, 0.10);
  --border-strong: rgba(111, 163, 30, 0.35);
  --text: #16211A;           /* 主文字：深墨绿黑 */
  --text-muted: #55655B;     /* 次级文字 */
  --text-dim: #8B998F;       /* 弱文字 */
  --radius: 14px;
  --radius-sm: 9px;
  --shadow: 0 20px 60px rgba(20, 33, 26, 0.10);
  --shadow-sm: 0 8px 24px rgba(20, 33, 26, 0.08);
  --maxw: 1180px;
  --header-h: 72px;
  --font: "Segoe UI", -apple-system, BlinkMacSystemFont, "PingFang SC",
          "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
  --mono: "SF Mono", "JetBrains Mono", Consolas, "Courier New", monospace;
}

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

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

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

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul, ol { list-style: none; }
button { font-family: inherit; cursor: pointer; }

::selection { background: var(--brand); color: var(--brand-ink); }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

.visually-hidden {
  position: absolute; width: 1px; height: 1px; margin: -1px;
  padding: 0; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* ==========================================================================
   页眉
   ========================================================================== */
.site-header {
  position: sticky; top: 0; z-index: 100;
  height: var(--header-h);
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  height: var(--header-h);
  display: flex; align-items: center; justify-content: space-between; gap: 24px;
}
.brand { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.brand .logo { height: 28px; width: auto; }

.main-nav { display: flex; align-items: center; gap: 6px; }
.main-nav a {
  padding: 9px 15px; border-radius: 8px; font-size: 15px; font-weight: 500;
  color: var(--text-muted); transition: color .18s, background .18s; white-space: nowrap;
}
.main-nav a:hover { color: var(--text); background: rgba(16, 30, 20, 0.05); }
.main-nav a.active { color: var(--brand-dark); }

.header-cta { display: flex; align-items: center; gap: 10px; }
.nav-toggle {
  display: none; width: 44px; height: 44px; border-radius: 10px;
  background: var(--bg-elevated); border: 1px solid var(--border); color: var(--text);
  align-items: center; justify-content: center; flex-direction: column; gap: 5px;
}
.nav-toggle span { display: block; width: 20px; height: 2px; background: var(--text); border-radius: 2px; transition: .2s; }

/* ==========================================================================
   按钮
   ========================================================================== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 26px; border-radius: 10px; font-size: 16px; font-weight: 600;
  border: 1px solid transparent; transition: transform .15s, box-shadow .2s, background .2s, border-color .2s, color .2s;
  white-space: nowrap;
}
.btn svg { width: 18px; height: 18px; }
.btn:active { transform: translateY(1px); }

.btn-primary {
  background: var(--brand); color: var(--brand-ink);
  box-shadow: 0 10px 30px rgba(165, 222, 55, 0.35);
}
.btn-primary:hover { background: #97CE2B; box-shadow: 0 12px 36px rgba(165, 222, 55, 0.5); transform: translateY(-1px); }

.btn-ghost { background: transparent; color: var(--text); border-color: var(--border-strong); }
.btn-ghost:hover { border-color: var(--brand-dark); color: var(--brand-dark); }

.btn-dark { background: var(--bg-elevated-2); color: var(--text); border-color: var(--border); }
.btn-dark:hover { border-color: var(--border-strong); }

.btn-lg { padding: 16px 34px; font-size: 17px; border-radius: 12px; }
.btn-sm { padding: 9px 18px; font-size: 14px; border-radius: 8px; }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  position: relative; overflow: hidden;
  padding: 92px 0 80px;
  background:
    radial-gradient(900px 480px at 78% -10%, rgba(165, 222, 55, 0.18), transparent 60%),
    radial-gradient(700px 420px at 8% 110%, rgba(165, 222, 55, 0.10), transparent 55%);
}
.hero .container { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 56px; align-items: center; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 7px 14px; border-radius: 999px; font-size: 13px; font-weight: 600;
  color: var(--brand-dark); background: rgba(165, 222, 55, 0.14); border: 1px solid var(--border-strong);
  margin-bottom: 22px;
}
.hero h1 { font-size: clamp(38px, 5.4vw, 62px); line-height: 1.08; font-weight: 800; letter-spacing: -0.5px; }
.hero h1 .accent { color: var(--brand-dark); }
.hero .lede { margin: 22px 0 30px; font-size: 19px; color: var(--text-muted); max-width: 560px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; }
.hero-meta { display: flex; flex-wrap: wrap; gap: 26px; margin-top: 40px; }
.hero-meta .item { display: flex; align-items: center; gap: 10px; color: var(--text-muted); font-size: 14px; }
.hero-meta .item svg { width: 20px; height: 20px; color: var(--brand-dark); flex-shrink: 0; }

.hero-visual { position: relative; display: flex; align-items: center; justify-content: center; }
.hero-card {
  width: 100%; max-width: 440px; background: var(--bg-elevated);
  border: 1px solid var(--border); border-radius: 20px; padding: 28px;
  box-shadow: var(--shadow);
}
.hero-card .win-bar { display: flex; gap: 7px; margin-bottom: 20px; }
.hero-card .win-bar i { width: 12px; height: 12px; border-radius: 50%; }
.hero-card .win-bar i:nth-child(1) { background: #FF5F57; }
.hero-card .win-bar i:nth-child(2) { background: #FEBC2E; }
.hero-card .win-bar i:nth-child(3) { background: #28C840; }

.step-row { display: flex; align-items: center; gap: 14px; padding: 15px 16px; border-radius: 12px; margin-bottom: 12px; background: var(--bg-elevated-2); border: 1px solid var(--border); }
.step-row .dot { width: 38px; height: 38px; border-radius: 10px; flex-shrink: 0; display: flex; align-items: center; justify-content: center; background: rgba(165, 222, 55, 0.16); color: var(--brand-dark); }
.step-row .dot svg { width: 20px; height: 20px; }
.step-row .st-label { font-size: 13px; color: var(--text-dim); }
.step-row .st-val { font-size: 15px; font-weight: 600; }
.step-row.done { border-color: var(--border-strong); }
.step-row.done .st-val { color: var(--brand-dark); }
.flash-bar { margin-top: 16px; }
.flash-bar .fb-row { display: flex; justify-content: space-between; font-size: 13px; color: var(--text-muted); margin-bottom: 8px; }
.progress { height: 9px; background: var(--bg-elevated-2); border-radius: 999px; overflow: hidden; }
.progress i { display: block; height: 100%; width: 62%; border-radius: 999px; background: linear-gradient(90deg, var(--brand-dark), var(--brand)); }

/* ==========================================================================
   通用 section
   ========================================================================== */
.section { padding: 84px 0; }
.section-head { max-width: 720px; margin: 0 auto 52px; text-align: center; }
.section-head h2 { font-size: clamp(28px, 3.4vw, 40px); font-weight: 800; letter-spacing: -0.4px; }
.section-head h2 .accent { color: var(--brand-dark); }
.section-head p { margin-top: 14px; color: var(--text-muted); font-size: 17px; }
.section-alt { background: var(--bg-elevated); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }

.eyebrow { display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: 0.14em; text-transform: uppercase; color: var(--brand-dark); margin-bottom: 14px; }

/* 特性卡片 */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.feature-card {
  background: var(--bg-elevated); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 30px 28px; transition: transform .2s, border-color .2s, box-shadow .2s;
}
.feature-card:hover { transform: translateY(-4px); border-color: var(--border-strong); box-shadow: var(--shadow-sm); }
.feature-card .fc-icon {
  width: 54px; height: 54px; border-radius: 13px; margin-bottom: 20px;
  display: flex; align-items: center; justify-content: center;
  background: rgba(165, 222, 55, 0.16); color: var(--brand-dark);
}
.feature-card .fc-icon svg { width: 26px; height: 26px; }
.feature-card h3 { font-size: 19px; font-weight: 700; margin-bottom: 10px; }
.feature-card p { color: var(--text-muted); font-size: 15px; }

/* 步骤 */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.step-card { position: relative; background: var(--bg-elevated); border: 1px solid var(--border); border-radius: var(--radius); padding: 34px 28px 30px; }
.step-card .num { font-size: 42px; font-weight: 800; color: var(--brand); line-height: 1; margin-bottom: 16px; }
.step-card h3 { font-size: 19px; margin-bottom: 10px; }
.step-card p { color: var(--text-muted); font-size: 15px; }

/* 使用场景 */
.use-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.use-card {
  background: var(--bg-elevated); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 30px 28px; transition: border-color .2s, transform .2s, box-shadow .2s;
}
.use-card:hover { border-color: var(--border-strong); transform: translateY(-3px); box-shadow: var(--shadow-sm); }
.use-card .uc-top { display: flex; align-items: center; gap: 14px; margin-bottom: 16px; }
.use-card .uc-icon { width: 48px; height: 48px; border-radius: 12px; background: rgba(165,222,55,.16); color: var(--brand-dark); display: flex; align-items: center; justify-content: center; }
.use-card .uc-icon svg { width: 24px; height: 24px; }
.use-card h3 { font-size: 18px; }
.use-card p { color: var(--text-muted); font-size: 15px; }

/* 用户评价 */
.quote-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.quote-card { background: var(--bg-elevated); border: 1px solid var(--border); border-radius: var(--radius); padding: 28px; display: flex; flex-direction: column; gap: 18px; }
.quote-card .stars { color: var(--brand-dark); font-size: 17px; letter-spacing: 2px; }
.quote-card blockquote { font-size: 15.5px; color: var(--text); line-height: 1.75; flex: 1; }
.quote-card figcaption { display: flex; align-items: center; gap: 12px; }
.quote-card .avatar {
  width: 42px; height: 42px; border-radius: 50%; flex-shrink: 0;
  background: linear-gradient(135deg, var(--brand), var(--brand-dark));
  color: var(--brand-ink); display: flex; align-items: center; justify-content: center; font-weight: 800; font-size: 16px;
}
.quote-card .who { font-size: 14px; font-weight: 600; }
.quote-card .role { font-size: 12.5px; color: var(--text-dim); }

/* ==========================================================================
   页面页眉（内页 hero 横幅）
   ========================================================================== */
.page-hero { padding: 72px 0 56px; text-align: center; background: radial-gradient(700px 360px at 50% -20%, rgba(165,222,55,.16), transparent 60%); }
.page-hero h1 { font-size: clamp(32px, 4.4vw, 48px); font-weight: 800; letter-spacing: -0.4px; }
.page-hero h1 .accent { color: var(--brand-dark); }
.page-hero p { margin: 16px auto 0; max-width: 680px; color: var(--text-muted); font-size: 18px; }

.breadcrumb { font-size: 14px; color: var(--text-dim); padding: 22px 0 0; }
.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--brand-dark); }
.breadcrumb .sep { margin: 0 8px; }

/* ==========================================================================
   下载中心
   ========================================================================== */
.dl-tabs { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-bottom: 40px; }
.dl-tab {
  padding: 12px 26px; border-radius: 10px; font-size: 15px; font-weight: 600;
  background: var(--bg-elevated); color: var(--text-muted); border: 1px solid var(--border);
  display: inline-flex; align-items: center; gap: 10px; transition: .18s;
}
.dl-tab svg { width: 20px; height: 20px; }
.dl-tab:hover { color: var(--text); border-color: var(--border-strong); }
.dl-tab.active { background: var(--brand); color: var(--brand-ink); border-color: var(--brand); }

.dl-panel { display: none; }
.dl-panel.active { display: block; }

.dl-card {
  background: var(--bg-elevated); border: 1px solid var(--border); border-radius: 18px;
  padding: 34px; margin-bottom: 22px;
}
.dl-card .dc-head { display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap; margin-bottom: 20px; }
.dl-card .dc-head h3 { font-size: 22px; }
.dl-card .dc-head .ver { font-size: 13px; color: var(--brand-dark); font-family: var(--mono); }
.dl-meta { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 22px; }
.chip { font-size: 13px; color: var(--text-muted); background: var(--bg-elevated-2); border: 1px solid var(--border); padding: 6px 12px; border-radius: 999px; }
.dl-actions { display: flex; flex-wrap: wrap; gap: 14px; }
.dl-note { font-size: 13.5px; color: var(--text-dim); margin-top: 16px; }

.code-block {
  background: var(--bg-elevated-2); border: 1px solid var(--border); border-radius: 12px;
  padding: 16px 18px; font-family: var(--mono); font-size: 14px; color: #2B3A30;
  overflow-x: auto; margin: 10px 0 4px; white-space: pre;
}
.code-block .c { color: var(--text-dim); }

/* 系统要求表 */
.req-table { width: 100%; border-collapse: collapse; font-size: 15px; }
.req-table th, .req-table td { text-align: left; padding: 14px 18px; border-bottom: 1px solid var(--border); }
.req-table th { color: var(--text-dim); font-weight: 600; font-size: 13px; letter-spacing: .04em; }
.req-table tr:last-child td { border-bottom: none; }
.req-table td:first-child { font-weight: 600; }

/* ==========================================================================
   FAQ
   ========================================================================== */
.faq-list { max-width: 820px; margin: 0 auto; }
.faq-item { border: 1px solid var(--border); border-radius: var(--radius); background: var(--bg-elevated); margin-bottom: 14px; overflow: hidden; }
.faq-q { width: 100%; text-align: left; padding: 20px 24px; background: transparent; border: none; color: var(--text); font-size: 16.5px; font-weight: 600; display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.faq-q .ico { flex-shrink: 0; width: 24px; height: 24px; color: var(--brand-dark); transition: transform .25s; }
.faq-item.open .faq-q .ico { transform: rotate(45deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height .3s ease; }
.faq-a .inner { padding: 0 24px 22px; color: var(--text-muted); font-size: 15px; }
.faq-item.open .faq-a { max-height: 600px; }

/* ==========================================================================
   CTA 横幅
   ========================================================================== */
.cta-banner { text-align: center; padding: 30px 24px; }
.cta-box {
  background: linear-gradient(135deg, rgba(165,222,55,.16), rgba(165,222,55,.05));
  border: 1px solid var(--border-strong); border-radius: 22px; padding: 60px 40px;
}
.cta-box h2 { font-size: clamp(26px, 3.4vw, 38px); font-weight: 800; }
.cta-box p { margin: 16px auto 28px; max-width: 560px; color: var(--text-muted); font-size: 17px; }

/* ==========================================================================
   页脚
   ========================================================================== */
.site-footer { border-top: 1px solid var(--border); padding: 64px 0 36px; background: var(--bg-elevated); }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr; gap: 40px; margin-bottom: 44px; }
.footer-brand p { color: var(--text-muted); font-size: 14.5px; margin-top: 16px; max-width: 320px; }
.footer-brand .logo { height: 26px; width: auto; }
.footer-col h4 { font-size: 14px; font-weight: 700; letter-spacing: .04em; margin-bottom: 16px; color: var(--text); }
.footer-col a { display: block; color: var(--text-muted); font-size: 14.5px; padding: 6px 0; transition: color .15s; }
.footer-col a:hover { color: var(--brand-dark); }
.footer-bottom { border-top: 1px solid var(--border); padding-top: 26px; display: flex; flex-wrap: wrap; justify-content: space-between; gap: 14px; font-size: 13.5px; color: var(--text-dim); }
.footer-bottom a { color: var(--text-dim); }
.footer-bottom a:hover { color: var(--brand-dark); }

/* ==========================================================================
   下载弹窗
   ========================================================================== */
.modal {
  position: fixed; inset: 0; z-index: 200;
  display: flex; align-items: center; justify-content: center; padding: 20px;
  opacity: 0; visibility: hidden; transition: opacity .22s ease, visibility .22s ease;
}
.modal.open { opacity: 1; visibility: visible;   left: 0;
  right: 0;
  top: 0;
  bottom: 0;}
  button { outline: none } 
.modal-overlay { position: absolute; inset: 0; background: rgba(16, 24, 32, 0.55); backdrop-filter: blur(4px); }
.modal-dialog {
  position: relative; width: 100%; max-width: 560px; background: var(--bg-elevated);
  border: 1px solid var(--border-strong); border-radius: 20px; padding: 34px 30px;
  box-shadow: var(--shadow); transform: translateY(16px) scale(.98); transition: transform .25s ease;
  max-height: 90vh; overflow-y: auto;
}
.modal.open .modal-dialog { transform: translateY(0) scale(1); }
.modal-close {
  position: absolute; top: 16px; right: 16px; width: 36px; height: 36px; border-radius: 10px;
  background: var(--bg-elevated-2); border: 1px solid var(--border); color: var(--text);
  display: flex; align-items: center; justify-content: center; font-size: 18px; transition: .15s;
}
.modal-close:hover { border-color: var(--brand-dark); color: var(--brand-dark); }
.modal-title { font-size: 22px; font-weight: 800; margin-bottom: 6px; }
.modal-sub { color: var(--text-muted); font-size: 14.5px; margin-bottom: 24px; }

.qr-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin-bottom: 22px; }
.qr-card { background: var(--bg); border: 1px solid var(--border); border-radius: 14px; padding: 20px; text-align: center; }
.qr-card img { width: 150px; height: 150px; margin: 0 auto 14px; border-radius: 8px; }
.qr-card .qr-name { font-weight: 700; font-size: 15px; }
.qr-card .qr-desc { font-size: 12.5px; color: var(--text-dim); margin-top: 4px; }
.qr-card .qr-hint { display: inline-block; margin-top: 10px; font-size: 12px; color: var(--brand-dark); }

.modal-foot { display: flex; flex-direction: column; gap: 12px; }
.modal-foot .divider { text-align: center; color: var(--text-dim); font-size: 13px; position: relative; }
.modal-foot .divider::before, .modal-foot .divider::after {
  content: ""; position: absolute; top: 50%; width: 38%; height: 1px; background: var(--border);
}
.modal-foot .divider::before { left: 0; }
.modal-foot .divider::after { right: 0; }
.modal-note { font-size: 12.5px; color: var(--text-dim); text-align: center; }

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width: 960px) {
  .hero .container { grid-template-columns: 1fr; gap: 48px; }
  .hero { padding: 64px 0 64px; }
  .feature-grid, .use-grid, .quote-grid, .steps { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 680px) {
  .nav-toggle { display: flex; }
  .main-nav {
    position: fixed; top: var(--header-h); left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 2px;
    background: var(--bg-elevated); border-bottom: 1px solid var(--border);
    padding: 12px 20px 18px; transform: translateY(-120%); transition: transform .28s ease;
    z-index: 99;
  }
  .main-nav.open { transform: translateY(0); }
  .main-nav a { padding: 13px 12px; font-size: 16px; }
  .header-cta .btn { display: none; }
  .feature-grid, .use-grid, .quote-grid, .steps { grid-template-columns: 1fr; }
  .qr-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
  .section { padding: 60px 0; }
  .hero-meta { gap: 18px; }
}

/* 无障碍：减少动效 */
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
  html { scroll-behavior: auto; }
}