/* ===========================================================================
   对外站点设计系统 / public site design system
   基调：浅色为主、柔和光晕、克制的动效。深色 CTA 与页脚制造节奏。
   =========================================================================== */

:root {
  --brand: #1c8fd0;
  --brand-2: #38b6f0;
  --brand-ink: #0d5a87;

  --ink: #0c1620;
  --ink-2: #46586b;
  --ink-3: #6d7f92;

  --bg: #ffffff;
  --bg-soft: #f4f8fb;
  --bg-tint: #eef6fc;
  --line: #e2eaf1;
  --line-soft: #eef3f7;

  --ok: #0f9d58;
  --warn: #d97706;

  --r-sm: 10px;
  --r: 14px;
  --r-lg: 20px;
  --r-xl: 28px;

  --sh-1: 0 1px 2px rgba(12, 22, 32, .04), 0 2px 8px rgba(12, 22, 32, .04);
  --sh-2: 0 4px 12px rgba(12, 22, 32, .06), 0 12px 32px rgba(12, 22, 32, .07);
  --sh-3: 0 8px 24px rgba(12, 22, 32, .08), 0 24px 64px rgba(12, 22, 32, .10);
  --sh-brand: 0 8px 28px rgba(28, 143, 208, .28);

  --maxw: 1120px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --brand: #3aa9e0;
    --brand-2: #5cc4f5;
    --brand-ink: #8ed3f5;

    --ink: #e8eff5;
    --ink-2: #a3b4c4;
    --ink-3: #7d8e9e;

    --bg: #0a0f15;
    --bg-soft: #0f161e;
    --bg-tint: #101d28;
    --line: #1e2a36;
    --line-soft: #16212b;

    --sh-1: 0 1px 2px rgba(0, 0, 0, .3);
    --sh-2: 0 4px 12px rgba(0, 0, 0, .35), 0 12px 32px rgba(0, 0, 0, .3);
    --sh-3: 0 8px 24px rgba(0, 0, 0, .4), 0 24px 64px rgba(0, 0, 0, .35);
    --sh-brand: 0 8px 28px rgba(58, 169, 224, .22);
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", Inter, Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.narrow { max-width: 820px; }

/* 滚动淡入 —— 尊重系统的"减少动态效果" */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .45s cubic-bezier(.16, 1, .3, 1), transform .45s cubic-bezier(.16, 1, .3, 1);
}
/* JS 未执行时不能把内容永久藏起来——没有脚本也要看得见 */
.no-js [data-reveal] { opacity: 1; transform: none; }
[data-reveal].in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  [data-reveal] { opacity: 1; transform: none; transition: none; }
}

/* ---------------------------------------------------------------- 导航 */
.nav {
  position: sticky; top: 0; z-index: 40;
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  border-bottom: 1px solid transparent;
  transition: border-color .25s, box-shadow .25s;
}
.nav.stuck { border-bottom-color: var(--line); box-shadow: var(--sh-1); }
.nav-in {
  max-width: var(--maxw); margin: 0 auto; padding: 14px 24px;
  display: flex; align-items: center; justify-content: space-between; gap: 20px;
}
.logo { display: inline-flex; align-items: center; gap: 10px; font-weight: 700; font-size: 17px; letter-spacing: -.01em; }
.logo-mark {
  width: 32px; height: 32px; border-radius: 9px; flex: 0 0 auto;
  background: linear-gradient(135deg, var(--brand-2), var(--brand));
  display: grid; place-items: center; box-shadow: var(--sh-brand);
}
.logo-mark svg { width: 17px; height: 17px; }

.nav-links { display: flex; align-items: center; gap: 4px; }
.nav-links a {
  padding: 8px 13px; border-radius: 9px; font-size: 14.5px; color: var(--ink-2);
  font-weight: 500; transition: color .18s, background .18s;
}
.nav-links a:hover { color: var(--ink); background: var(--bg-soft); }
.nav-links .lang { font-size: 13px; color: var(--ink-3); }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 11px 22px; border-radius: 11px; border: 1px solid transparent;
  font-size: 15px; font-weight: 600; cursor: pointer; white-space: nowrap;
  transition: transform .18s cubic-bezier(.16,1,.3,1), box-shadow .18s, background .18s, border-color .18s;
}
.btn-primary {
  background: linear-gradient(135deg, var(--brand-2), var(--brand));
  color: #fff !important; box-shadow: var(--sh-brand);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 34px rgba(28, 143, 208, .36); }
.btn-ghost { background: var(--bg); color: var(--ink) !important; border-color: var(--line); }
.btn-ghost:hover { border-color: var(--ink-3); transform: translateY(-2px); }
.btn-sm { padding: 8px 16px; font-size: 14px; border-radius: 9px; }
.btn-lg { padding: 15px 30px; font-size: 16px; border-radius: 13px; }
.btn-block { display: flex; width: 100%; }

@media (max-width: 820px) {
  .nav-links .hide-sm { display: none; }
}

/* ---------------------------------------------------------------- Hero */
.hero { position: relative; padding: 84px 0 0; text-align: center; overflow: hidden; }
.hero::before, .hero::after {
  content: ""; position: absolute; border-radius: 50%; pointer-events: none;
  filter: blur(80px); opacity: .5; z-index: 0;
}
.hero::before {
  width: 620px; height: 620px; top: -320px; left: 50%; transform: translateX(-58%);
  background: radial-gradient(circle, rgba(56, 182, 240, .55), transparent 68%);
}
.hero::after {
  width: 460px; height: 460px; top: -180px; right: -140px;
  background: radial-gradient(circle, rgba(28, 143, 208, .32), transparent 68%);
}
.hero > * { position: relative; z-index: 1; }

.pill {
  display: inline-flex; align-items: center; gap: 9px;
  font-size: 13.5px; font-weight: 550; color: var(--brand-ink);
  background: var(--bg-tint); border: 1px solid color-mix(in srgb, var(--brand) 22%, transparent);
  padding: 7px 8px 7px 14px; border-radius: 30px; margin-bottom: 26px;
}
.pill b {
  background: var(--bg); border-radius: 20px; padding: 3px 11px;
  font-size: 12.5px; font-weight: 600; color: var(--ink-2);
}

h1.hero-h {
  font-size: clamp(34px, 5.6vw, 60px); line-height: 1.1; margin: 0 0 22px;
  letter-spacing: -.033em; font-weight: 760;
}
h1.hero-h .grad {
  background: linear-gradient(120deg, var(--brand-2), var(--brand) 55%, var(--brand-ink));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero-sub {
  font-size: clamp(16.5px, 2vw, 20px); color: var(--ink-2); line-height: 1.6;
  max-width: 660px; margin: 0 auto 34px;
}
.hero-cta { display: flex; gap: 13px; justify-content: center; flex-wrap: wrap; }
.hero-note {
  margin: 20px 0 0; font-size: 13.5px; color: var(--ink-3);
  display: flex; gap: 20px; justify-content: center; flex-wrap: wrap;
}
.hero-note span { display: inline-flex; align-items: center; gap: 6px; }
.hero-note svg { width: 14px; height: 14px; color: var(--ok); flex: 0 0 auto; }

/* 产品示意：网页窗口 ⇄ Telegram 窗口 */
.showcase {
  margin: 58px auto 0; max-width: 940px; padding: 0 24px;
  display: grid; grid-template-columns: 1fr auto 1fr; gap: 20px; align-items: center;
}
@media (max-width: 880px) {
  .showcase { grid-template-columns: 1fr; gap: 14px; max-width: 420px; }
  .showcase .flow { transform: rotate(90deg); margin: 2px auto; }
}
.win {
  border: 1px solid var(--line); border-radius: var(--r-lg); overflow: hidden;
  background: var(--bg); box-shadow: var(--sh-3); text-align: left;
}
.win-bar {
  display: flex; align-items: center; gap: 7px; padding: 11px 14px;
  background: var(--bg-soft); border-bottom: 1px solid var(--line-soft);
}
.win-bar i { width: 9px; height: 9px; border-radius: 50%; background: var(--line); }
.win-bar span { margin-left: 6px; font-size: 12px; color: var(--ink-3); font-weight: 500; }
.win-bar.tg { background: linear-gradient(135deg, var(--brand-2), var(--brand)); border-bottom-color: transparent; }
.win-bar.tg i { background: rgba(255, 255, 255, .45); }
.win-bar.tg span { color: #fff; }
.win-body { padding: 16px; display: flex; flex-direction: column; gap: 9px; min-height: 168px; }
.thread-label {
  font-size: 11.5px; color: var(--ink-3); padding-bottom: 9px; margin-bottom: 3px;
  border-bottom: 1px dashed var(--line);
}
.msg { max-width: 84%; padding: 9px 13px; font-size: 13.5px; line-height: 1.5; border-radius: 14px; }
.msg.in { background: var(--bg-soft); align-self: flex-start; border-bottom-left-radius: 5px; }
.msg.out {
  background: linear-gradient(135deg, var(--brand-2), var(--brand)); color: #fff;
  align-self: flex-end; border-bottom-right-radius: 5px;
}
.msg-meta { font-size: 10.5px; opacity: .75; margin-top: 3px; display: block; }
.flow { display: grid; place-items: center; color: var(--brand); }
.flow svg { width: 30px; height: 30px; }

/* ---------------------------------------------------------------- 指标条 */
.metrics {
  margin-top: 72px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line);
  background: var(--bg-soft);
}
.metrics .wrap { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; padding-block: 34px; }
@media (max-width: 760px) { .metrics .wrap { grid-template-columns: repeat(2, 1fr); gap: 26px; } }
.metric { text-align: center; }
.metric b {
  display: block; font-size: clamp(24px, 3.4vw, 32px); font-weight: 720;
  letter-spacing: -.02em; line-height: 1.15;
  background: linear-gradient(120deg, var(--brand-2), var(--brand-ink));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.metric span { display: block; font-size: 13.5px; color: var(--ink-2); margin-top: 5px; }

/* ---------------------------------------------------------------- 通用节 */
section { position: relative; }
.sec { padding: 92px 0; }
.sec-soft { background: var(--bg-soft); }
.sec-head { text-align: center; max-width: 640px; margin: 0 auto 54px; }
.kicker {
  display: inline-block; font-size: 13px; font-weight: 650; letter-spacing: .06em;
  text-transform: uppercase; color: var(--brand); margin-bottom: 13px;
}
.sec-head h2 {
  font-size: clamp(26px, 3.8vw, 40px); line-height: 1.18; margin: 0 0 14px;
  letter-spacing: -.025em; font-weight: 730;
}
.sec-head p { font-size: 16.5px; color: var(--ink-2); margin: 0; line-height: 1.6; }

/* ---------------------------------------------------------------- 三大支柱（图文交错） */
.feature {
  display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center;
  padding: 56px 0;
}
.feature + .feature { border-top: 1px solid var(--line-soft); }
.feature.flip .f-text { order: 2; }
@media (max-width: 900px) {
  .feature { grid-template-columns: 1fr; gap: 34px; padding: 42px 0; }
  .feature.flip .f-text { order: 0; }
}

.f-icon {
  width: 50px; height: 50px; border-radius: 15px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--brand-2), var(--brand));
  box-shadow: var(--sh-brand); margin-bottom: 20px;
}
.f-icon svg { width: 24px; height: 24px; color: #fff; }
.f-text h3 {
  font-size: clamp(22px, 2.8vw, 29px); margin: 0 0 14px; letter-spacing: -.02em;
  font-weight: 700; line-height: 1.25;
}
.f-text > p { font-size: 16px; color: var(--ink-2); margin: 0 0 24px; line-height: 1.65; }
.f-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 14px; }
.f-list li { display: flex; gap: 12px; align-items: flex-start; font-size: 15px; }
.f-list .tick {
  width: 21px; height: 21px; border-radius: 50%; flex: 0 0 auto; margin-top: 1px;
  background: color-mix(in srgb, var(--ok) 14%, transparent);
  display: grid; place-items: center;
}
.f-list .tick svg { width: 12px; height: 12px; color: var(--ok); }
.f-list strong { display: block; font-weight: 620; margin-bottom: 2px; }
.f-list span { color: var(--ink-2); font-size: 14px; line-height: 1.55; }

/* 支柱配图 */
.f-visual {
  border: 1px solid var(--line); border-radius: var(--r-lg); padding: 26px;
  background: var(--bg); box-shadow: var(--sh-2); position: relative; overflow: hidden;
}
.f-visual::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(120% 80% at 80% 0%, color-mix(in srgb, var(--brand) 8%, transparent), transparent 60%);
  pointer-events: none;
}
.vrow {
  display: flex; align-items: center; gap: 12px; padding: 13px 15px;
  border: 1px solid var(--line-soft); border-radius: var(--r-sm);
  background: var(--bg-soft); font-size: 14px; position: relative;
}
.vrow + .vrow { margin-top: 10px; }
.vrow .vico { width: 18px; height: 18px; flex: 0 0 auto; color: var(--brand); }
.vrow .vok { margin-left: auto; color: var(--ok); font-size: 12.5px; font-weight: 600; white-space: nowrap; }
.vrow .vno { margin-left: auto; color: var(--ink-3); font-size: 12.5px; text-decoration: line-through; }
.vmask { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 13px; }
.vnote { margin: 16px 0 0; font-size: 12.5px; color: var(--ink-3); line-height: 1.55; position: relative; }

/* ---------------------------------------------------------------- 能力网格 */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
@media (max-width: 900px) { .grid-3 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .grid-3 { grid-template-columns: 1fr; } }

.card {
  border: 1px solid var(--line); border-radius: var(--r); padding: 26px 24px;
  background: var(--bg); transition: transform .22s cubic-bezier(.16,1,.3,1), box-shadow .22s, border-color .22s;
}
.card:hover { transform: translateY(-3px); box-shadow: var(--sh-2); border-color: color-mix(in srgb, var(--brand) 30%, var(--line)); }
.card .cico {
  width: 40px; height: 40px; border-radius: 11px; display: grid; place-items: center;
  background: var(--bg-tint); margin-bottom: 15px;
}
.card .cico svg { width: 19px; height: 19px; color: var(--brand); }
.card h4 { margin: 0 0 7px; font-size: 16px; font-weight: 650; }
.card p { margin: 0; font-size: 14px; color: var(--ink-2); line-height: 1.6; }

/* ---------------------------------------------------------------- 步骤 */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; position: relative; }
@media (max-width: 860px) { .steps { grid-template-columns: 1fr; gap: 20px; } }
.step {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--r);
  padding: 28px 24px; position: relative;
}
.step-n {
  width: 34px; height: 34px; border-radius: 10px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--brand-2), var(--brand)); color: #fff;
  font-weight: 700; font-size: 15px; margin-bottom: 16px; box-shadow: var(--sh-brand);
}
.step h4 { margin: 0 0 8px; font-size: 17px; font-weight: 650; }
.step p { margin: 0; font-size: 14.5px; color: var(--ink-2); line-height: 1.6; }
.step .tag {
  display: inline-block; margin-top: 14px; font-size: 12.5px; color: var(--brand-ink);
  background: var(--bg-tint); padding: 4px 11px; border-radius: 20px; font-weight: 550;
}

/* ---------------------------------------------------------------- 对比 */
.compare {
  border: 1px solid var(--line); border-radius: var(--r-lg); overflow: hidden;
  background: var(--bg); box-shadow: var(--sh-1);
}
.compare table { width: 100%; border-collapse: collapse; }
.compare th, .compare td { padding: 16px 20px; text-align: left; font-size: 14.5px; }
.compare thead th {
  background: var(--bg-soft); font-size: 13px; font-weight: 650; color: var(--ink-2);
  border-bottom: 1px solid var(--line);
}
.compare thead th:last-child { color: var(--brand); }
.compare tbody tr + tr td { border-top: 1px solid var(--line-soft); }
.compare td:first-child { font-weight: 550; }
.compare td.no { color: var(--ink-3); }
.compare td.yes { color: var(--ink); }
.compare td.yes::before {
  content: "✓"; color: var(--ok); font-weight: 700; margin-right: 8px;
}
@media (max-width: 700px) {
  .compare th, .compare td { padding: 12px 13px; font-size: 13.5px; }
}

/* ---------------------------------------------------------------- 价格 */
.plans { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; align-items: stretch; }
@media (max-width: 1000px) { .plans { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 560px) { .plans { grid-template-columns: 1fr; } }

.plan {
  position: relative; display: flex; flex-direction: column;
  border: 1px solid var(--line); border-radius: var(--r-lg); padding: 28px 24px;
  background: var(--bg); transition: transform .22s cubic-bezier(.16,1,.3,1), box-shadow .22s;
}
.plan:hover { transform: translateY(-4px); box-shadow: var(--sh-2); }
.plan.hot {
  border-color: transparent; box-shadow: var(--sh-3);
  background:
    linear-gradient(var(--bg), var(--bg)) padding-box,
    linear-gradient(135deg, var(--brand-2), var(--brand)) border-box;
  border: 1.5px solid transparent;
}
.plan .flag {
  position: absolute; top: -12px; left: 50%; transform: translateX(-50%);
  background: linear-gradient(135deg, var(--brand-2), var(--brand)); color: #fff;
  font-size: 12px; font-weight: 650; padding: 5px 14px; border-radius: 20px;
  white-space: nowrap; box-shadow: var(--sh-brand);
}
.plan h3 { margin: 0 0 4px; font-size: 17px; font-weight: 650; }
.plan .pdesc { margin: 0 0 18px; font-size: 13.5px; color: var(--ink-3); min-height: 20px; }
.plan .amt { display: flex; align-items: baseline; gap: 5px; margin-bottom: 22px; }
.plan .amt b { font-size: 36px; font-weight: 740; letter-spacing: -.03em; line-height: 1; }
.plan .amt small { font-size: 13px; color: var(--ink-3); }
.plan ul { list-style: none; margin: 0 0 24px; padding: 0; flex: 1; display: grid; gap: 11px; }
.plan li { display: flex; gap: 10px; align-items: flex-start; font-size: 14px; color: var(--ink-2); }
.plan li svg { width: 15px; height: 15px; color: var(--ok); flex: 0 0 auto; margin-top: 4px; }

/* ---------------------------------------------------------------- FAQ */
.faq { max-width: 800px; margin: 0 auto; }
.faq details {
  border: 1px solid var(--line); border-radius: var(--r); background: var(--bg);
  margin-bottom: 12px; overflow: hidden; transition: border-color .2s, box-shadow .2s;
}
.faq details[open] { border-color: color-mix(in srgb, var(--brand) 34%, var(--line)); box-shadow: var(--sh-1); }
.faq summary {
  cursor: pointer; padding: 19px 22px; font-size: 15.5px; font-weight: 600;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: ""; width: 9px; height: 9px; flex: 0 0 auto;
  border-right: 2px solid var(--ink-3); border-bottom: 2px solid var(--ink-3);
  transform: rotate(45deg) translate(-2px, -2px); transition: transform .22s;
}
.faq details[open] summary::after { transform: rotate(-135deg) translate(-2px, -2px); }
.faq .a { padding: 0 22px 20px; font-size: 14.5px; color: var(--ink-2); line-height: 1.7; }

/* ---------------------------------------------------------------- 深色 CTA */
.cta-dark {
  background: linear-gradient(135deg, #0d2233, #123449 55%, #0d2233);
  color: #fff; text-align: center; padding: 86px 0; position: relative; overflow: hidden;
}
.cta-dark::before {
  content: ""; position: absolute; width: 700px; height: 700px; border-radius: 50%;
  top: -420px; left: 50%; transform: translateX(-50%); filter: blur(90px);
  background: radial-gradient(circle, rgba(56, 182, 240, .38), transparent 65%);
}
.cta-dark > * { position: relative; }
.cta-dark h2 {
  font-size: clamp(26px, 3.8vw, 40px); margin: 0 0 14px; letter-spacing: -.025em; font-weight: 730;
}
.cta-dark p { font-size: 17px; color: rgba(255, 255, 255, .72); margin: 0 0 32px; }
.cta-dark .btn-ghost {
  background: rgba(255, 255, 255, .07); color: #fff !important;
  border-color: rgba(255, 255, 255, .22);
}
.cta-dark .btn-ghost:hover { background: rgba(255, 255, 255, .13); }
.cta-dark .hero-note { color: rgba(255, 255, 255, .55); }
.cta-dark .hero-note svg { color: #5cd6a0; }

/* ---------------------------------------------------------------- 页脚 */
.foot { background: var(--bg-soft); border-top: 1px solid var(--line); padding: 54px 0 30px; }
.foot-grid {
  display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 34px; margin-bottom: 38px;
}
@media (max-width: 800px) { .foot-grid { grid-template-columns: 1fr 1fr; gap: 28px; } }
.foot-brand p { font-size: 14px; color: var(--ink-2); margin: 14px 0 0; max-width: 280px; line-height: 1.6; }
.foot h5 { font-size: 13px; font-weight: 650; margin: 0 0 14px; color: var(--ink); }
.foot ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.foot ul a { font-size: 14px; color: var(--ink-2); }
.foot ul a:hover { color: var(--brand); }
.foot-bot {
  border-top: 1px solid var(--line); padding-top: 22px;
  display: flex; justify-content: space-between; gap: 14px; flex-wrap: wrap;
  font-size: 13px; color: var(--ink-3);
}

/* ---------------------------------------------------------------- 认证页 */
.auth {
  min-height: 100vh; display: grid; grid-template-columns: 1.05fr .95fr;
}
@media (max-width: 940px) { .auth { grid-template-columns: 1fr; } .auth-side { display: none; } }

.auth-side {
  background: linear-gradient(150deg, #0d2233, #14405c 60%, #0d2233);
  color: #fff; padding: 52px 56px; display: flex; flex-direction: column;
  position: relative; overflow: hidden;
}
.auth-side::before {
  content: ""; position: absolute; width: 520px; height: 520px; border-radius: 50%;
  top: -180px; right: -180px; filter: blur(80px);
  background: radial-gradient(circle, rgba(56, 182, 240, .42), transparent 65%);
}
.auth-side > * { position: relative; }
.auth-side .logo { color: #fff; }
.auth-side h2 {
  font-size: clamp(25px, 2.6vw, 33px); line-height: 1.25; margin: auto 0 22px;
  letter-spacing: -.02em; font-weight: 700; max-width: 420px;
}
.auth-points { list-style: none; margin: 0 0 auto; padding: 0; display: grid; gap: 18px; max-width: 400px; }
.auth-points li { display: flex; gap: 13px; align-items: flex-start; }
.auth-points .tick {
  width: 24px; height: 24px; border-radius: 8px; flex: 0 0 auto; margin-top: 1px;
  background: rgba(255, 255, 255, .12); display: grid; place-items: center;
}
.auth-points .tick svg { width: 13px; height: 13px; color: #5cd6a0; }
.auth-points strong { display: block; font-size: 15px; font-weight: 620; margin-bottom: 3px; }
.auth-points span { font-size: 13.5px; color: rgba(255, 255, 255, .66); line-height: 1.55; }

.auth-main {
  display: flex; align-items: center; justify-content: center; padding: 44px 24px;
  background: var(--bg);
}
.auth-card { width: 100%; max-width: 400px; }
.auth-card .top-logo { display: none; margin-bottom: 30px; }
@media (max-width: 940px) { .auth-card .top-logo { display: inline-flex; } }
.auth-card h1 { font-size: 27px; margin: 0 0 8px; letter-spacing: -.02em; font-weight: 720; }
.auth-card .lede { color: var(--ink-2); font-size: 14.5px; margin: 0 0 30px; }

.field { margin-bottom: 17px; }
.field label { display: block; font-size: 13.5px; font-weight: 550; margin-bottom: 7px; color: var(--ink); }
.field input {
  width: 100%; padding: 12px 14px; font: inherit; font-size: 15px;
  border: 1px solid var(--line); border-radius: 11px; background: var(--bg-soft);
  color: var(--ink); outline: none; transition: border-color .18s, box-shadow .18s, background .18s;
}
.field input:focus {
  border-color: var(--brand); background: var(--bg);
  box-shadow: 0 0 0 3.5px color-mix(in srgb, var(--brand) 15%, transparent);
}
.field .row-between { display: flex; align-items: baseline; justify-content: space-between; gap: 10px; }
.field .row-between a { font-size: 13px; color: var(--brand); font-weight: 550; }
.field .hint { font-size: 12.5px; color: var(--ink-3); margin: 7px 0 0; }

.alert { padding: 12px 15px; border-radius: 11px; font-size: 14px; margin-bottom: 20px; line-height: 1.55; }
.alert-err { background: color-mix(in srgb, #dc2626 9%, transparent); color: #c02626; }
.alert-ok { background: color-mix(in srgb, var(--ok) 11%, transparent); color: var(--ok); }
.alert-info { background: var(--bg-tint); color: var(--brand-ink); }

.auth-foot { margin: 26px 0 0; text-align: center; font-size: 14px; color: var(--ink-2); }
.auth-foot a { color: var(--brand); font-weight: 600; }
.auth-legal { margin: 22px 0 0; font-size: 12px; color: var(--ink-3); text-align: center; line-height: 1.6; }
.back-home {
  display: inline-flex; align-items: center; gap: 6px; font-size: 13.5px;
  color: var(--ink-3); margin-bottom: 22px;
}
.back-home:hover { color: var(--ink); }

/* 套餐卡里"不含"的那条：灰掉并画一条删除线，比不写更清楚 */
.plan ul li.off { color: var(--ink-3); opacity: .75; padding-left: 26px; position: relative; }
.plan ul li.off::before { content: '—'; position: absolute; left: 6px; }

/* ---------------------------------------------- AI 与翻译展示 */
.sec-ai { background: linear-gradient(180deg, var(--bg-soft, #f6f8fb), transparent); }
.ai-duo { display: grid; gap: 20px; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); }
.ai-card {
  background: #fff; border: 1px solid var(--line); border-radius: 16px;
  padding: 24px; display: flex; flex-direction: column;
}
.ai-card-head { display: flex; gap: 14px; align-items: flex-start; margin-bottom: 18px; }
.ai-ico {
  flex: none; width: 38px; height: 38px; border-radius: 11px;
  display: grid; place-items: center; color: #fff;
  background: linear-gradient(135deg, var(--brand), #6c5ce7);
}
.ai-card-head h3 { font-size: 17px; font-weight: 640; letter-spacing: -.01em; margin: 2px 0 4px; }
.ai-card-head p { font-size: 13.5px; color: var(--ink-3); line-height: 1.55; }

.ai-demo {
  background: var(--bg-soft, #f6f8fb); border-radius: 12px; padding: 16px;
  display: flex; flex-direction: column; gap: 12px; flex: 1;
}
.demo-row { display: flex; flex-direction: column; gap: 5px; align-items: flex-start; }
.demo-row.you { align-items: flex-end; }
.demo-row .who { font-size: 11px; font-weight: 650; color: var(--ink-3);
                 letter-spacing: .03em; padding: 0 2px; }
.ai-demo .bub {
  max-width: 92%; padding: 10px 13px; border-radius: 13px; font-size: 14px;
  line-height: 1.5; background: #fff; box-shadow: 0 1px 3px rgba(16, 24, 40, .06);
}
.ai-demo .bub.out { background: var(--brand); color: #fff; }
.ai-demo .bub em {
  display: block; margin-top: 7px; padding-top: 6px; font-style: normal;
  font-size: 12.5px; line-height: 1.45; opacity: .72;
  border-top: 1px solid currentColor;
  border-color: color-mix(in srgb, currentColor 18%, transparent);
}

.ai-draft {
  border: 1px solid color-mix(in srgb, var(--brand) 35%, transparent);
  background: color-mix(in srgb, var(--brand) 7%, transparent);
  border-radius: 12px; padding: 12px 14px; font-size: 14px; line-height: 1.5;
}
.ai-draft b { display: block; font-size: 11px; font-weight: 700; letter-spacing: .04em;
              color: var(--brand); margin-bottom: 5px; }
.ai-btns { display: flex; gap: 7px; margin-top: 10px; }
.ai-btns span {
  font-size: 12px; font-weight: 550; padding: 5px 11px; border-radius: 7px;
  background: rgba(16, 24, 40, .06); color: var(--ink-2);
}
.ai-btns span.on { background: var(--brand); color: #fff; }

.ai-foot { margin-top: 14px; font-size: 12.5px; color: var(--ink-3); line-height: 1.55; }