/* tbxvpn 官网统一样式：深色科技感基调，全部颜色与间距通过令牌集中管理。 */

/* ===== 设计令牌 ===== */
:root {
  /* 背景层次：页面底 → 区块底 → 卡片面 */
  --bg: #070f13;
  --bg-soft: #0a171d;
  --panel: #0f2028;
  --panel-hi: #142b34;

  /* 描边与分隔 */
  --line: rgba(233, 244, 244, .09);
  --line-strong: rgba(233, 244, 244, .16);

  /* 文本：正文与次级文本均满足 4.5:1 对比度 */
  --ink: #e9f4f4;
  --muted: #8ba7ae;
  --faint: #6b858c;

  /* 品牌色：延续会员中心青绿，深色底上提亮以保证可读性 */
  --brand: #12b3a4;
  --brand-deep: #087f75;
  --tg: #2aabee;
  --grad: linear-gradient(135deg, #2aabee 0%, #12b3a4 100%);

  /* 状态色 */
  --warn: #e0a54a;

  /* 节奏：区块纵向间距与圆角统一 */
  --gap-section: clamp(72px, 9vw, 132px);
  --radius: 16px;
  --radius-sm: 10px;
  --shell: 1180px;

  --shadow: 0 24px 70px rgba(0, 0, 0, .45);
  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ===== 基础 ===== */
*, *::before, *::after { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.75 -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  overflow-wrap: anywhere;
  /* 顶部与右下的两处柔光，制造深色科技感但不干扰文本可读性 */
  background-image:
    radial-gradient(760px 420px at 50% -8%, rgba(42, 171, 238, .16), transparent 70%),
    radial-gradient(620px 420px at 100% 12%, rgba(18, 179, 164, .10), transparent 65%);
  background-repeat: no-repeat;
}

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

img, svg { max-width: 100%; }
button { font: inherit; cursor: pointer; }

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

h1, h2, h3, h4 { margin: 0; line-height: 1.25; letter-spacing: -.01em; font-weight: 700; }
p { margin: 0; }
ul, ol { margin: 0; padding: 0; }

.shell { width: 100%; max-width: var(--shell); margin: 0 auto; padding: 0 clamp(20px, 5vw, 40px); }

.section { padding: var(--gap-section) 0; }
.section--tint { background: var(--bg-soft); border-block: 1px solid var(--line); }

/* 区块标题统一结构：眉标 + 主标 + 副述 */
.eyebrow {
  display: inline-block;
  margin-bottom: 14px;
  color: var(--brand);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .22em;
  text-transform: uppercase;
}
.section-head { max-width: 660px; margin-bottom: clamp(36px, 5vw, 60px); }
.section-head.center { margin-inline: auto; text-align: center; }
.section-head h2 { font-size: clamp(28px, 3.6vw, 42px); }
.section-head p { margin-top: 16px; color: var(--muted); font-size: clamp(15px, 1.5vw, 17px); }

.gradient-text {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-height: 48px;
  padding: 0 26px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  white-space: nowrap;
  transition: transform .18s var(--ease), box-shadow .18s var(--ease), background .18s var(--ease);
}
.btn--primary { background: var(--grad); color: #04161a; box-shadow: 0 12px 34px rgba(18, 179, 164, .28); }
.btn--primary:hover { color: #04161a; transform: translateY(-2px); box-shadow: 0 18px 44px rgba(18, 179, 164, .36); }
.btn--ghost { border-color: var(--line-strong); color: var(--ink); background: rgba(233, 244, 244, .04); }
.btn--ghost:hover { border-color: var(--brand); color: var(--ink); background: rgba(18, 179, 164, .10); }
.btn--sm { min-height: 40px; padding: 0 18px; font-size: 14px; }
.btn--block { width: 100%; }

/* ===== 顶部导航 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(7, 15, 19, .82);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.site-header .shell {
  display: flex;
  align-items: center;
  gap: 20px;
  height: 70px;
}
.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--ink); font-size: 19px; font-weight: 700; letter-spacing: -.02em; }
.brand:hover { color: var(--ink); }
.brand-mark { display: block; width: 34px; height: 34px; flex: 0 0 34px; }
.brand b { font-weight: 700; }

.nav { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.nav a {
  padding: 8px 14px;
  border-radius: 8px;
  color: var(--muted);
  font-size: 15px;
  transition: color .16s, background .16s;
}
.nav a:hover { color: var(--ink); background: rgba(233, 244, 244, .06); }
.nav a[aria-current="page"] { color: var(--ink); background: rgba(18, 179, 164, .12); }

.header-actions { display: flex; align-items: center; gap: 10px; }

/* 语言切换：两段式开关，当前语言高亮 */
.lang-switch { display: inline-flex; padding: 3px; border: 1px solid var(--line-strong); border-radius: 999px; background: rgba(233, 244, 244, .04); }
.lang-switch button {
  min-width: 42px;
  padding: 5px 10px;
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  font-size: 13px;
  font-weight: 600;
  transition: color .16s, background .16s;
}
.lang-switch button[aria-pressed="true"] { background: var(--brand-deep); color: #fff; }

/* 移动端汉堡菜单按钮，桌面端隐藏 */
.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--line-strong);
  border-radius: 10px;
  background: rgba(233, 244, 244, .04);
  color: var(--ink);
}
.nav-toggle svg { display: block; margin: auto; }

/* ===== 首屏 ===== */
.hero { position: relative; padding: clamp(72px, 11vw, 132px) 0 clamp(64px, 8vw, 104px); overflow: hidden; }
.hero-inner { max-width: 820px; }
.hero h1 { font-size: clamp(36px, 6.2vw, 68px); line-height: 1.1; letter-spacing: -.03em; }
.hero-sub { margin-top: 22px; max-width: 620px; color: var(--muted); font-size: clamp(16px, 1.9vw, 19px); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 36px; }
.hero-note { margin-top: 20px; color: var(--faint); font-size: 13px; }

/* 首屏下方的能力标签条 */
.pill-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 44px; }
.pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(233, 244, 244, .03);
  color: var(--muted);
  font-size: 13px;
}
.pill svg { color: var(--brand); flex: 0 0 auto; }

/* ===== 通用网格与卡片 ===== */
.grid { display: grid; gap: 20px; }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }

.card {
  padding: clamp(24px, 2.6vw, 32px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, var(--panel) 0%, rgba(15, 32, 40, .55) 100%);
  transition: border-color .2s var(--ease), transform .2s var(--ease);
}
.card:hover { border-color: var(--line-strong); transform: translateY(-3px); }
.card h3 { margin-bottom: 12px; font-size: 19px; }
.card p { color: var(--muted); font-size: 15px; }

.card-icon {
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  margin-bottom: 20px;
  border-radius: 12px;
  background: rgba(18, 179, 164, .13);
  color: var(--brand);
}

/* ===== 三步流程 ===== */
.steps { counter-reset: step; }
.step { position: relative; padding-left: 60px; }
.step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(18, 179, 164, .35);
  border-radius: 12px;
  background: rgba(18, 179, 164, .10);
  color: var(--brand);
  font-size: 17px;
  font-weight: 700;
}
.step h3 { margin-bottom: 10px; font-size: 18px; }
.step p { color: var(--muted); font-size: 15px; }

/* ===== 数据指标条 ===== */
.stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 1px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--line); overflow: hidden; }
.stat { padding: clamp(24px, 3vw, 34px); background: var(--panel); text-align: center; }
.stat b { display: block; font-size: clamp(26px, 3.4vw, 38px); font-variant-numeric: tabular-nums; letter-spacing: -.02em; }
.stat span { display: block; margin-top: 8px; color: var(--muted); font-size: 13px; }
/* 指标数值尚未确定，占位状态降低视觉权重并标注待定 */
.stat[data-placeholder] b { color: var(--faint); }

/* ===== 多设备条 ===== */
.device-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 14px; }
.device {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 22px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--panel);
  font-size: 15px;
  font-weight: 600;
}
.device svg { color: var(--brand); }

/* ===== 价格 ===== */
.plan-grid { display: grid; gap: 20px; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); align-items: start; }
.plan {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: clamp(26px, 2.8vw, 34px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, var(--panel) 0%, rgba(15, 32, 40, .5) 100%);
}
.plan--featured { border-color: rgba(18, 179, 164, .5); box-shadow: 0 0 0 1px rgba(18, 179, 164, .2), var(--shadow); }
.plan-badge {
  position: absolute;
  top: -12px;
  left: clamp(26px, 2.8vw, 34px);
  padding: 4px 13px;
  border-radius: 999px;
  background: var(--grad);
  color: #04161a;
  font-size: 12px;
  font-weight: 700;
}
.plan h3 { font-size: 20px; }
/* 价格允许整体换行，但金额本身不得从中间断开（body 的 overflow-wrap:anywhere 会这么做） */
.plan-price { display: flex; flex-wrap: wrap; align-items: baseline; gap: 2px 6px; margin: 18px 0 6px; }
.plan-price b {
  font-size: clamp(32px, 7vw, 40px);
  font-variant-numeric: tabular-nums;
  letter-spacing: -.03em;
  overflow-wrap: normal;
  word-break: keep-all;
}
.plan-price span { overflow-wrap: normal; white-space: nowrap; }
.plan-price span { color: var(--muted); font-size: 14px; }
.plan-note { color: var(--faint); font-size: 13px; min-height: 20px; }
.plan-specs { margin: 24px 0; padding-top: 22px; border-top: 1px solid var(--line); list-style: none; display: grid; gap: 12px; }
.plan-specs li { display: flex; gap: 10px; color: var(--muted); font-size: 14.5px; }
.plan-specs svg { flex: 0 0 auto; margin-top: 6px; color: var(--brand); }
.plan-specs b { color: var(--ink); font-weight: 600; }
.plan .btn { margin-top: auto; }

/* 套餐数据加载中的骨架占位 */
.plan--skeleton { pointer-events: none; }
.skeleton-bar { height: 12px; border-radius: 6px; background: rgba(233, 244, 244, .07); }
.skeleton-bar + .skeleton-bar { margin-top: 12px; }
.skeleton-bar.w60 { width: 60%; }
.skeleton-bar.w40 { width: 40%; }
.skeleton-bar.tall { height: 34px; margin-bottom: 18px; }

/* 价格数据来源提示（实时 / 兜底） */
.plan-source { margin-top: 26px; color: var(--faint); font-size: 13px; text-align: center; }
.plan-source[data-state="fallback"] { color: var(--warn); }

/* ===== 通用清单 ===== */
.check-list { list-style: none; display: grid; gap: 13px; }
.check-list li { display: flex; gap: 11px; color: var(--muted); font-size: 15px; }
.check-list svg { flex: 0 0 auto; margin-top: 6px; color: var(--brand); }

/* ===== FAQ 手风琴 ===== */
.faq { display: grid; gap: 12px; max-width: 840px; margin: 0 auto; }
.faq details { border: 1px solid var(--line); border-radius: var(--radius-sm); background: var(--panel); overflow: hidden; }
.faq details[open] { border-color: var(--line-strong); }
.faq summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 19px 22px;
  list-style: none;
  font-size: 16px;
  font-weight: 600;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "";
  flex: 0 0 auto;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--brand);
  border-bottom: 2px solid var(--brand);
  transform: rotate(45deg) translateY(-3px);
  transition: transform .2s var(--ease);
}
.faq details[open] summary::after { transform: rotate(-135deg) translateY(-3px); }
.faq .faq-body { padding: 0 22px 20px; color: var(--muted); font-size: 15px; }

/* ===== 教程步骤（下载页） ===== */
.guide { display: grid; gap: 18px; }
.guide-item { display: grid; grid-template-columns: 38px minmax(0, 1fr); gap: 18px; align-items: start; padding: 22px; border: 1px solid var(--line); border-radius: var(--radius-sm); background: var(--panel); }
.guide-num { display: grid; place-items: center; width: 38px; height: 38px; border-radius: 10px; background: rgba(42, 171, 238, .14); color: var(--tg); font-weight: 700; }
.guide-item h3 { margin-bottom: 8px; font-size: 17px; }
.guide-item p { color: var(--muted); font-size: 15px; }

/* ===== 行动召唤 ===== */
.cta {
  padding: clamp(40px, 6vw, 72px);
  border: 1px solid rgba(18, 179, 164, .28);
  border-radius: clamp(20px, 3vw, 28px);
  background:
    radial-gradient(620px 300px at 50% 0%, rgba(42, 171, 238, .16), transparent 70%),
    linear-gradient(180deg, var(--panel-hi) 0%, var(--panel) 100%);
  text-align: center;
}
.cta h2 { font-size: clamp(26px, 3.4vw, 38px); }
.cta p { margin: 16px auto 0; max-width: 540px; color: var(--muted); }
.cta .hero-actions { justify-content: center; }

/* ===== 正文长文（条款页） ===== */
.prose { max-width: 820px; }
.prose h2 { margin: 44px 0 14px; font-size: 22px; }
.prose h2:first-child { margin-top: 0; }
.prose h3 { margin: 26px 0 10px; font-size: 17px; }
.prose p { margin-bottom: 14px; color: var(--muted); font-size: 15.5px; }
.prose ul { margin: 0 0 16px; padding-left: 20px; color: var(--muted); font-size: 15.5px; }
.prose li { margin-bottom: 8px; }
.prose strong { color: var(--ink); }

/* 未定稿内容的提示条 */
.notice {
  display: flex;
  gap: 12px;
  padding: 15px 18px;
  border: 1px solid rgba(224, 165, 74, .3);
  border-left: 3px solid var(--warn);
  border-radius: var(--radius-sm);
  background: rgba(224, 165, 74, .07);
  color: #e6cfa5;
  font-size: 14px;
}
.notice svg { flex: 0 0 auto; margin-top: 4px; color: var(--warn); }

/* ===== 内页页头 ===== */
.page-head { padding: clamp(52px, 7vw, 82px) 0 clamp(30px, 4vw, 46px); }
.page-head h1 { font-size: clamp(30px, 4.4vw, 46px); }
.page-head p { margin-top: 16px; max-width: 620px; color: var(--muted); font-size: clamp(15px, 1.6vw, 17px); }

/* ===== 页脚 ===== */
.site-footer { padding: clamp(50px, 6vw, 72px) 0 40px; border-top: 1px solid var(--line); background: var(--bg-soft); }
.footer-top { display: grid; grid-template-columns: minmax(0, 1.4fr) repeat(2, minmax(0, 1fr)); gap: 40px; }
.footer-brand p { margin-top: 16px; max-width: 320px; color: var(--muted); font-size: 14px; }
.footer-col h4 { margin-bottom: 16px; font-size: 13px; letter-spacing: .12em; text-transform: uppercase; color: var(--faint); }
.footer-col ul { list-style: none; display: grid; gap: 10px; }
.footer-col a { color: var(--muted); font-size: 14.5px; }
.footer-col a:hover { color: var(--ink); }
.footer-col li > span { color: var(--faint); font-size: 14.5px; }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 14px; margin-top: 44px; padding-top: 26px; border-top: 1px solid var(--line); color: var(--faint); font-size: 13px; }

/* ===== 入场动效 ===== */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .6s var(--ease), transform .6s var(--ease); }
.reveal.is-visible { opacity: 1; transform: none; }

/* ===== 响应式 ===== */
@media (max-width: 1023px) {
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-top { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 860px) {
  .nav-toggle { display: block; }
  /* 窄屏导航改为下拉面板，默认收起 */
  .nav {
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    margin: 0;
    padding: 12px clamp(20px, 5vw, 40px) 20px;
    background: rgba(7, 15, 19, .97);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--line);
  }
  .nav[hidden] { display: none; }
  .nav a { padding: 12px 14px; font-size: 16px; }
  .header-actions { margin-left: auto; }
  .header-actions .btn { display: none; }
  .nav .btn { display: inline-flex; margin-top: 10px; }
}

@media (min-width: 861px) {
  /* 桌面端导航常驻显示，忽略脚本写入的 hidden */
  .nav[hidden] { display: flex; }
  .nav .btn { display: none; }
}

@media (max-width: 767px) {
  .grid--3, .grid--2, .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .stats { grid-template-columns: minmax(0, 1fr); }
  .footer-top { grid-template-columns: minmax(0, 1fr); }
  .hero-actions .btn { flex: 1 1 auto; }
  .guide-item { grid-template-columns: minmax(0, 1fr); gap: 12px; }
}

/* 尊重系统的减少动态效果偏好 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
  .reveal { opacity: 1; transform: none; }
}