/* 基础主题与重置 */
:root {
  color-scheme: dark;
  --bg: #0f1117;
  --bg-2: #12151e;
  --surface: #161a22;
  --border: #273046;
  --text: #e6e9ef;
  --muted: #a8b0c0;
  --primary: #b10505; /* 中国红 */
  --primary-2: #c91f1f;
  --gold: #f0c66e;
  --success: #4caf50;
  --error: #ff4d4f;
  --shadow: rgba(0,0,0,.35);
}
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", Arial, sans-serif;
  /* 红色主题主背景：深红到亮红的竖向渐变，并叠加金色与亮红的光晕 */
  background:
    radial-gradient(1000px 500px at 20% 0%, rgba(255,82,82,.35), transparent 70%),
    radial-gradient(1200px 600px at 80% 100%, rgba(255,200,80,.20), transparent 70%),
    linear-gradient(180deg, #7a0b0f 0%, #b51216 40%, #d9232e 70%, #b51216 100%);
  color: var(--text);
}

/* 红色背景的光晕与纹理 */
.bg-red::before {
  content: "";
  position: fixed; inset: 0;
  background:
    radial-gradient(80px 80px at 18% 22%, rgba(255,200,100,.30), transparent 70%),
    radial-gradient(40px 40px at 68% 12%, rgba(255,255,255,.18), transparent 65%),
    radial-gradient(140px 140px at 50% 86%, rgba(255,120,120,.20), transparent 75%);
  mix-blend-mode: screen;
  pointer-events: none;
  z-index: 0;
}
.bg-red::after {
  content: "";
  position: fixed; inset: 0;
  background: repeating-linear-gradient(20deg, rgba(255,255,255,.06) 0 60px, rgba(255,255,255,0) 60px 120px);
  opacity: .25;
  pointer-events: none;
  z-index: 0;
}

.container { width: min(1080px, 92vw); margin-inline: auto; }
.row { display: flex; gap: 16px; }
.column { display: flex; flex-direction: column; gap: 16px; }
.center { align-items: center; justify-content: center; }
.between { justify-content: space-between; }

/* 头部 */
.site-header {
  position: sticky; top: 0; z-index: 10;
  background: linear-gradient(180deg, rgba(22,26,34,.80), rgba(22,26,34,.35));
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--border);
}
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 700; letter-spacing: .5px; }
.brand-icon { color: var(--gold); filter: drop-shadow(0 2px 6px rgba(240,198,110,.35)); }
.brand-title { font-size: 16px; }
.nav { display: flex; align-items: center; gap: 10px; }
.nav-link { color: var(--muted); text-decoration: none; padding: 10px 14px; border-radius: 10px; }
.nav-link:hover { color: var(--text); background: rgba(255,255,255,.06); }

/* 头部绿色安全认证徽标 */
.trust-green { display: inline-flex; align-items: center; gap: 8px; padding: 8px 12px; border-radius: 999px; background: rgba(46, 204, 113, .14); color: #2ecc71; font-weight: 700; border: 1px solid rgba(46, 204, 113, .45); box-shadow: 0 2px 8px rgba(46,204,113,.25); }
.trust-green .dot { width: 10px; height: 10px; border-radius: 50%; background: #2ecc71; box-shadow: 0 0 0 3px rgba(46,204,113,.18); }
@media (max-width: 540px) { .trust-green { display:none; } }

/* 按钮 */
.btn { cursor: pointer; border: none; border-radius: 12px; padding: 12px 18px; font-weight: 600; }
.btn-primary { background: linear-gradient(180deg, var(--primary), var(--primary-2)); color: #fff; box-shadow: 0 6px 18px rgba(185,5,5,.35); }
.btn-primary:hover { filter: brightness(1.05); }
.btn-outline { background: transparent; color: var(--text); border: 1px solid var(--border); }
.btn-outline:hover { border-color: var(--gold); color: var(--gold); }
.btn-ghost { background: rgba(255,255,255,.06); color: var(--text); }
.btn-ghost:hover { background: rgba(255,255,255,.10); }

/* 首屏 */
.hero { position: relative; z-index: 1; padding: 64px 0 48px; text-align: center; }
.hero-title { font-size: clamp(28px, 6vw, 52px); margin: 0; font-weight: 800; letter-spacing: 1px;
  background: linear-gradient(90deg, #fff, var(--gold)); -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero-subtitle { color: var(--muted); font-size: clamp(14px, 3.7vw, 18px); line-height: 1.7; }
.hero-actions { display: inline-flex; gap: 12px; margin-top: 10px; }
.hero-info { display: flex; gap: 8px; justify-content: center; margin-top: 18px; flex-wrap: wrap; }
.info-chip { border: 1px solid var(--border); padding: 8px 12px; border-radius: 999px; background: rgba(255,255,255,.05); color: var(--muted); }

/* 区块通用 */
.section { padding: 36px 0; }
.section-title { font-size: 22px; margin: 0 0 18px; }
.bullet-list { margin: 0; padding-left: 18px; color: var(--muted); line-height: 1.8; }

/* 步骤卡片 */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.step-card { background: linear-gradient(180deg, rgba(22,26,34,.9), rgba(22,26,34,.6)); border: 1px solid var(--border); border-radius: 16px; padding: 18px;
  box-shadow: 0 12px 28px var(--shadow);
}
.step-index { width: 32px; height: 32px; border-radius: 50%; background: var(--gold); color: #1a1a1a; display: grid; place-items: center; font-weight: 800; }
.step-title { font-weight: 700; margin-top: 10px; }
.step-desc { color: var(--muted); margin-top: 6px; }

/* FAQ */
.faq .faq-item { border: 1px solid var(--border); border-radius: 12px; padding: 12px 16px; background: rgba(255,255,255,.05); margin-bottom: 10px; }
.faq summary { cursor: pointer; font-weight: 600; }
.faq p { color: var(--muted); margin: 8px 0 0; }

/* 页脚 */
.site-footer { padding: 22px 0 34px; color: var(--muted); }

/* 弹窗 */
.modal { position: fixed; inset: 0; display: none; z-index: 30; }
.modal.open { display: block; }
.modal-backdrop { position: absolute; inset: 0; background: rgba(0,0,0,.5); backdrop-filter: blur(2px); }
.modal-dialog { position: relative; width: min(640px, 92vw); margin: 8vh auto; background: linear-gradient(180deg, rgba(22,26,34,.92), rgba(22,26,34,.80)); border: 1px solid var(--border); border-radius: 16px; padding: 18px 18px 4px; box-shadow: 0 24px 48px var(--shadow); }

.form-row { display: grid; gap: 8px; margin-bottom: 12px; }
.form-row.checkbox { grid-template-columns: 18px 1fr; align-items: center; }
label { color: var(--muted); font-size: 14px; }
input[type="text"], input[type="tel"], input[type="number"] {
  width: 100%; padding: 12px 14px; border-radius: 12px; border: 1px solid var(--border); background: rgba(255,255,255,.06); color: var(--text);
}
input::placeholder { color: #8e96a8; }
.form-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 8px; }
.form-tip { color: var(--muted); font-size: 12px; margin: 10px 2px; }
.form-error { color: var(--error); font-weight: 600; }
.form-success { color: var(--success); font-weight: 600; }

/* 响应式 */
@media (max-width: 860px) {
  .steps { grid-template-columns: 1fr; }
}

/* 下载区块 */
.download-grid { display: grid; grid-template-columns: 1.5fr .9fr; gap: 16px; }
.download-card { background: linear-gradient(180deg, rgba(22,26,34,.9), rgba(22,26,34,.6)); border: 1px solid var(--border); border-radius: 16px; padding: 18px; box-shadow: 0 12px 28px var(--shadow); }
.download-title { margin: 0 0 8px; font-size: 18px; font-weight: 700; }
.download-desc { color: var(--muted); margin: 0 0 12px; }
.download-actions { display: flex; gap: 10px; }
.download-meta { display: flex; gap: 12px; color: var(--muted); margin-top: 12px; font-size: 13px; flex-wrap: wrap; }
.qr-box { background: linear-gradient(180deg, rgba(22,26,34,.9), rgba(22,26,34,.6)); border: 1px solid var(--border); border-radius: 16px; padding: 18px; display: grid; place-content: start; box-shadow: 0 12px 28px var(--shadow); }
.qr-image-wrap { width: 180px; height: 180px; border-radius: 12px; overflow: hidden; border: 1px dashed var(--border); display: grid; place-items: center; background: rgba(255,255,255,.04); }
.qr-tip { color: var(--muted); font-size: 13px; }
.install-tips details { border: 1px solid var(--border); border-radius: 12px; padding: 12px 16px; background: rgba(255,255,255,.05); }

/* 首屏统计卡 */
.hero-stats { display: flex; gap: 10px; flex-wrap: wrap; justify-content: center; margin: 8px 0 10px; }
.stat-card { display: grid; gap: 4px; padding: 10px 12px; border: 1px solid var(--border); border-radius: 12px; background: rgba(255,255,255,.05); min-width: 160px; }
.stat-label { color: var(--muted); font-size: 12px; }
.stat-value { font-size: 18px; font-weight: 800; color: var(--gold); }

@media (max-width: 860px) {
  .download-grid { grid-template-columns: 1fr; }
}

/* 仿真风格（简版） */
.replica-block { display: none; text-align: center; margin-top: 14px; }
.replica-line { font-size: 22px; color: var(--gold); margin: 8px 0; }
.replica-title { font-size: clamp(28px, 5.5vw, 40px); font-weight: 800; margin: 6px 0; letter-spacing: 2px; color: #ffd34a; text-shadow: 0 2px 12px rgba(0,0,0,.35); }
.replica-text { font-size: 16px; color: #ffe8b0; margin: 8px 0; line-height: 1.9; }

.replica-cta { display: inline-block; margin: 18px 0 10px; padding: 14px 22px; border-radius: 999px; background: linear-gradient(180deg, #ffd166, #f9b64f); color: #7a0b0f; font-weight: 800; box-shadow: 0 10px 24px rgba(249,182,79,.35); }
.replica-cta:focus { outline: 2px solid #ffd16655; outline-offset: 2px; }
.replica-tip { color: #ffd98f; font-size: 14px; margin: 6px 0 16px; }

.replica-downloads { display: grid; gap: 14px; justify-content: center; margin: 8px 0 16px; }
.replica-btn { display: inline-block; text-align: center; width: min(520px, 92vw); padding: 16px 18px; border-radius: 12px; background: #ff6b6b; color: #fff; font-weight: 800; box-shadow: 0 10px 24px rgba(255,0,0,.25); text-decoration: none; }
.replica-btn:hover { filter: brightness(1.05); }

/* 仿真模式下隐藏复杂元素（保留头部） */
/* body.replica-mode .site-header { display: none; } */
body.replica-mode .hero-title,
body.replica-mode .hero-subtitle,
body.replica-mode .hero-stats,
body.replica-mode .hero-actions,
body.replica-mode .hero-info { display: none; }
body.replica-mode .replica-block { display: block; }

/* 可信认证区块已移除（保留头部绿标样式） */

/* 移动端底部固定下载栏 */
.mobile-sticky { position: fixed; left: 0; right: 0; bottom: 0; z-index: 1000; display: none; gap: 10px; padding: 10px 14px; background: linear-gradient(180deg, rgba(22,26,34,.6), rgba(22,26,34,.92)); border-top: 1px solid var(--border); box-shadow: 0 -6px 18px var(--shadow); backdrop-filter: saturate(1.2) blur(8px); transition: transform .24s ease, opacity .24s ease; }
.mobile-sticky.is-hidden { transform: translateY(120%); opacity: 0; pointer-events: none; }
.sticky-btn { flex: 1; display: inline-block; text-align: center; padding: 14px 16px; border-radius: 12px; font-weight: 800; text-decoration: none; }
.sticky-btn { background: linear-gradient(180deg, var(--primary), var(--primary-2)); color: #fff; box-shadow: 0 6px 18px rgba(185,5,5,.35); }
.sticky-btn.secondary { background: rgba(255,255,255,.06); color: var(--text); border: 1px solid var(--border); box-shadow: none; }

@media (max-width: 680px) {
  .mobile-sticky { display: grid; grid-template-columns: 1fr 1fr; padding-bottom: calc(10px + env(safe-area-inset-bottom)); }
  body { padding-bottom: calc(110px + env(safe-area-inset-bottom)); }
  .site-footer { padding-bottom: 10px; }
  .hero { padding: 42px 0 28px; }
  .btn { padding: 14px 16px; }
}