/* ============================================================
   拥春 · Landing Page
   Figma: file w1yEwtRyWACCPhy3QIh0mh · node 204590:7477 (1307 × 3298)

   全部色值、字号、字体、圆角均取自 Figma REST API 的真实节点数据，
   非推断值。设计稿中没有任何阴影效果，因此这里也不加阴影。
   ============================================================ */

:root {
  /* — 颜色（取自 Figma） — */
  --c-ink:          #000000;   /* 所有正文/标题 */
  --c-header-bg:    #f8f8f8;   /* Frame 2117128857 */
  --c-primary:      #9636f3;   /* 下载按钮 Rectangle 1329130423 */
  --c-nav-active:   #d8b5f3;   /* 导航「首页」 */
  --c-on-primary:   #ffffff;

  /* 页面底图：Rectangle 1329130631 · GRADIENT_LINEAR · opacity 0.4 覆盖白底
     角度由 gradientHandlePositions 换算：(0.021,0.352) → (0.904,0.672)
     在 1359×3481 画布上换算为 CSS 133deg */
  --page-gradient: linear-gradient(
      133deg,
      rgba(233, 219, 239, .4)   0%,
      rgba(233, 217, 233, .4)  25%,
      rgba(230, 184, 213, .4)  35.6%,
      rgba(218, 175, 219, .4)  52%,
      rgba(233,  51, 179, .4)  80%
  );

  /* — 字体（Figma 中使用 ADLaM Display / Source Han Sans CN / Noto Sans SC / Inter）
       Source Han Sans CN 与 Noto Sans SC 为同一字体的双品牌版本，此处统一用后者。
       ADLaM Display 无中文字形，浏览器会回退到中文字体 —— 与 Figma 中的表现一致。 */
  --font-cjk:     "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-display: "ADLaM Display", var(--font-cjk);
  --font-brand:   "Inter", var(--font-cjk);

  /* — 字号（Figma 实测） — */
  --fs-h1:      40px;   /* ADLaM Display · lh 52.2 */
  --fs-h2:      48px;   /* Noto Sans SC  · lh 57.6 */
  --fs-h2-lg:   64px;   /* 「纯粹交友」 */
  --fs-lead:    20px;   /* hero 正文 · lh 26.1 */
  --fs-body:    24px;   /* 其余正文 · lh 40 · ls 0.72 */
  --fs-nav:     22px;   /* Source Han Sans CN Bold · ls 0.66 */
  --fs-brand:   48px;   /* Inter */
  --fs-btn:     20px;   /* Source Han Sans CN Bold */

  /* — 布局 — */
  --page-w:      1307px;
  --gutter:      74px;
  --radius-btn:  40px;
  --header-h:    132px;
}

/* ── reset ─────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  background: #fff;          /* 阻止 body 背景向 canvas 传播，保证渐变按文档高度铺满 */
}

body {
  margin: 0;
  font-family: var(--font-cjk);
  color: var(--c-ink);
  background-image: var(--page-gradient);
  background-repeat: no-repeat;
  background-size: 100% 100%;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { display: block; max-width: 100%; height: auto; }
a   { text-decoration: none; color: inherit; }
h1, h2, p { margin: 0; }

/* ── shared shell ──────────────────────────────────────── */
.section-inner {
  width: 100%;
  max-width: var(--page-w);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { position: relative; }

/* ── buttons ───────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 120px;
  height: 56px;
  border-radius: var(--radius-btn);
  font-family: var(--font-cjk);
  font-size: var(--fs-btn);
  font-weight: 700;
  line-height: 29.6px;
  transition: transform .2s ease, filter .2s ease;
}

.btn-primary {
  background: var(--c-primary);
  color: var(--c-on-primary);
}

.btn-primary:hover  { filter: brightness(1.1); transform: translateY(-2px); }
.btn-primary:active { transform: translateY(0); }

/* ── header ────────────────────────────────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  background: var(--c-header-bg);
}

.header-inner {
  height: 100%;
  max-width: var(--page-w);
  margin-inline: auto;
  padding-inline: 55px;
  display: flex;
  align-items: center;
  gap: 40px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 32px;
  flex-shrink: 0;
}

.brand-icon { width: 108px; height: 108px; }

.brand-name {
  font-family: var(--font-brand);
  font-size: var(--fs-brand);
  font-weight: 400;
  line-height: 1;
  color: var(--c-ink);
}

.nav {
  display: flex;
  align-items: center;
  gap: 60px;
  margin-inline: auto;
  font-size: var(--fs-nav);
  font-weight: 700;
  line-height: 32.6px;
  letter-spacing: .66px;
}

.nav a { position: relative; padding-block: 6px; transition: color .2s ease; }
.nav a.is-active { color: var(--c-nav-active); }

.nav a::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 0;
  width: 0;
  height: 3px;
  border-radius: 2px;
  background: var(--c-primary);
  transform: translateX(-50%);
  transition: width .26s ease;
}

.nav a:hover { color: var(--c-primary); }
.nav a:hover::after { width: 100%; }

.header-cta { flex-shrink: 0; }

/* ── hero ──────────────────────────────────────────────── */
.hero { padding-block: 120px 140px; }

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 560px) minmax(0, 1fr);
  gap: 80px;
  align-items: center;
}

.h1 {
  font-family: var(--font-display);
  font-size: var(--fs-h1);
  line-height: 1.305;        /* 52.2 / 40 */
  font-weight: 400;
}

.lead {
  margin-top: 38px;
  font-family: var(--font-display);
  font-size: var(--fs-lead);
  line-height: 1.9;          /* 设计稿正文行间以空行分隔，此处用行距还原 */
  font-weight: 400;
}

.hero-copy .btn { margin-top: 48px; }

.hero-visual { position: relative; }

.phone { margin-inline: auto; }

/* 圆角取自各自节点 */
.phone-login   { width: 390px; border-radius: 40px; }
.phone-chat    { width: 364px; border-radius: 20px; }
.phone-video   { width: 544px; border-radius: 0; }
.phone-profile { width: 368px; border-radius: 40px; }

.deco {
  position: absolute;
  pointer-events: none;
  user-select: none;
}

.deco-heart {
  width: 95px;
  top: -18px;
  left: 4%;
  animation: float 6s ease-in-out infinite;
}

/* ── split sections ────────────────────────────────────── */
/* 列宽比例对应 Figma 中各文本块宽度：聊天 650 · 视频 642 · 认证 674 */
.split {
  display: grid;
  gap: 80px;
  align-items: center;
}

.split-media-left  { grid-template-columns: minmax(0, 420px) minmax(0, 1fr); }
.split-media-right { grid-template-columns: minmax(0, 1fr) minmax(0, 420px); }

.section-video .split-media-right {
  grid-template-columns: minmax(0, 1fr) minmax(0, 544px);
  gap: 70px;
}

.media { position: relative; }
.copy  { position: relative; }

.h1, .h2 { text-wrap: balance; }

.h2 {
  font-family: var(--font-cjk);
  font-size: var(--fs-h2);
  line-height: 1.2;          /* 57.6 / 48 */
  font-weight: 400;
  letter-spacing: 1.44px;
}

.h2-lg {
  font-size: var(--fs-h2-lg);
  letter-spacing: 1.92px;
}

.body {
  font-size: var(--fs-body);
  line-height: 40px;
  letter-spacing: .72px;
  font-weight: 400;
}

.copy .body { margin-top: 34px; }

/* — 02 chat — */
.section-chat { padding-block: 100px; }

.deco-megaphone {
  width: 215px;
  right: -60px;
  bottom: -70px;
  animation: float 7s ease-in-out infinite;
}

.deco-bubble {
  width: 101px;
  top: -110px;
  right: 40px;
  animation: float 5.5s ease-in-out infinite;
}

/* — 03 video — */
.section-video { padding-block: 140px; }

/* — 04 trust — */
.section-trust { padding-block: 120px; }

/* — 05 closing — */
.section-closing { padding-block: 150px 170px; }

.closing-inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 60px;
}

.closing-text { max-width: 856px; }

.deco-cat {
  position: static;
  width: 277px;
  flex-shrink: 0;
  animation: float 6.5s ease-in-out infinite;
}

/* ── footer ────────────────────────────────────────────── */
.site-footer {
  padding-block: 56px 48px;
  background: var(--c-ink);
  color: rgba(255, 255, 255, .78);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 34px;
}

.footer-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  flex-wrap: wrap;
  padding-bottom: 30px;
  border-bottom: 1px solid rgba(255, 255, 255, .13);
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 24px;
  font-weight: 700;
  color: #fff;
}

.footer-brand img { border-radius: 10px; }

.footer-nav { display: flex; gap: 40px; font-size: 17px; }
.footer-nav a:hover { color: var(--c-nav-active); }

/* — 备案 / 主体信息 — */
.footer-info {
  display: flex;
  flex-direction: column;
  gap: 14px;
  font-size: 15px;
  line-height: 1.8;
}

.footer-company {
  font-size: 17px;
  font-weight: 700;
  color: #fff;
}

.footer-meta {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 36px;
  color: rgba(255, 255, 255, .68);
}

.footer-meta li { display: flex; align-items: baseline; gap: 8px; }

/* 「电话/地址/邮箱/备案号」标签，定宽让各行对齐 */
.footer-meta .k {
  flex-shrink: 0;
  color: rgba(255, 255, 255, .42);
}

.footer-meta .k::after { content: "："; }

.footer-meta a {
  color: rgba(255, 255, 255, .78);
  transition: color .2s ease;
}

.footer-meta a:hover { color: var(--c-nav-active); }

.footer-icp {
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-color: rgba(255, 255, 255, .3);
}

.footer-icp:hover { text-decoration-color: var(--c-nav-active); }

.footer-copy {
  font-size: 14px;
  color: rgba(255, 255, 255, .4);
}

/* ── motion ────────────────────────────────────────────── */
@keyframes float {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50%      { transform: translateY(-16px) rotate(-3deg); }
}

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
}

/* ── responsive ────────────────────────────────────────── */
@media (max-width: 1180px) {
  :root {
    --fs-h1: 34px;
    --fs-h2: 40px;
    --fs-h2-lg: 50px;
    --fs-body: 21px;
    --fs-brand: 38px;
    --gutter: 48px;
  }

  .body { line-height: 34px; }

  .header-inner { padding-inline: 40px; gap: 28px; }
  .brand { gap: 20px; }
  .brand-icon { width: 76px; height: 76px; }
  .nav { gap: 40px; font-size: 19px; }

  .hero-inner,
  .split-media-left,
  .split-media-right { gap: 56px; }

  .phone-video { width: 420px; }
}

@media (max-width: 900px) {
  .site-header { height: auto; padding-block: 18px; }

  .header-inner {
    flex-wrap: wrap;
    justify-content: center;
    row-gap: 18px;
  }

  .nav { margin-inline: 0; order: 3; width: 100%; justify-content: center; }

  .hero { padding-block: 72px 90px; }

  /* 不用 justify-items: center —— 那会让网格项按 max-content 定宽，
     导致 <br> 硬换行的长句溢出视口。改为拉伸 + margin auto。 */
  .hero-inner,
  .split-media-left,
  .split-media-right,
  .section-video .split-media-right {
    grid-template-columns: minmax(0, 1fr);
    gap: 64px;
    text-align: center;
  }

  .split-media-right .media { order: -1; }

  .hero-copy, .copy {
    width: 100%;
    max-width: 640px;
    margin-inline: auto;
  }
  .hero-copy .btn { margin-inline: auto; }

  .deco-megaphone { right: -10px; bottom: -50px; width: 150px; }
  .deco-bubble    { top: -80px; right: 0; width: 78px; }

  .closing-inner { flex-direction: column; text-align: center; }
  .closing-text  { width: 100%; }
  .deco-cat { width: 200px; }

  .footer-top  { justify-content: center; }
  .footer-info { align-items: center; text-align: center; }
  .footer-meta { justify-content: center; }
}

@media (max-width: 560px) {
  :root {
    --fs-h1: 25px;
    --fs-h2: 27px;
    --fs-h2-lg: 32px;
    --fs-lead: 16px;
    --fs-body: 17px;
    --fs-nav: 16px;
    --fs-brand: 28px;
    --fs-btn: 17px;
    --gutter: 22px;
  }

  .body { line-height: 30px; letter-spacing: .4px; }
  .h2   { letter-spacing: .8px; }
  .h2-lg{ letter-spacing: 1px; }

  .brand-icon { width: 58px; height: 58px; }
  .brand { gap: 14px; }
  .nav { gap: 26px; }
  .btn { width: 104px; height: 48px; }

  .phone-login, .phone-chat, .phone-video, .phone-profile {
    width: 100%;
    max-width: 320px;
  }
  .phone-login, .phone-profile { border-radius: 32px; }

  .footer-nav { gap: 24px; }

  /* 地址较长，窄屏改为逐条竖排 */
  .footer-meta {
    flex-direction: column;
    align-items: center;
    gap: 10px;
  }
  .footer-meta li { flex-direction: column; align-items: center; gap: 2px; }
  .footer-meta .k::after { content: ""; }
}