/* 心洞 · Oasis 官网 —— 设计系统
   DIRECTION CONTRACT
   THESIS: 心洞是一个温暖、私密的情绪树洞——把心事放下、被听见；拒绝 SaaS 功能格子落地页，
           做成能"呼吸"的一段绿意，由东东(豆芽)领着你往下走。Persuade(首页)+Read(协议/支持)。
   OWN-WORLD: App 的疗愈世界——薄荷绿底(#F6FBF5/#EFF8ED)、招牌绿→青柠渐变(#55B4A1→#91D14C)、
           心情卡薄荷渐变(#D0EEC7→#85C290)、墨字三级(#232423/#5E6159/#959993)、大圆角柔卡+#E1EDDE 淡影、
           东东内联 SVG(渐变绿身+叶子+点眼+微笑+腮红)在呼吸。暖、圆、不慌不忙。
   FIRST VIEWPORT: 全幅薄荷天光，东东居中呼吸，一句"有情绪，来心洞说说"，柔和下载键。
*/

:root {
  /* —— 品牌绿 —— */
  --accent: #55AB95;
  --accent-deep: #3E8C79;
  --grad-a: #55B4A1;
  --grad-b: #91D14C;
  --mint-a: #D0EEC7;
  --mint-b: #85C290;
  --leaf-a: #91D14C;
  --leaf-b: #55AB95;

  /* —— 底色 —— */
  --bg: #F3FAF1;
  --bg-2: #EAF4E7;
  --sky-top: #E4F3E9;
  --sky-bot: #F6FBF5;
  --card: #FFFFFF;
  --card-soft: rgba(255, 255, 255, 0.72);

  /* —— 墨字 —— */
  --ink: #232423;
  --ink-2: #5E6159;
  --ink-3: #6E736C;   /* 三级文字：加深以过 WCAG AA 4.5:1（原 #959993 仅约 2.8:1） */
  --on-accent: #FFFFFF;

  /* —— 影/线 —— */
  --line: #E4F0E1;
  --shadow-soft: 0 8px 30px rgba(85, 171, 149, 0.10);
  --shadow-card: 0 20px 60px -22px rgba(56, 120, 100, 0.28);
  --shadow-float: 0 30px 80px -30px rgba(56, 120, 100, 0.42);

  /* —— 版式 —— */
  --font-cjk: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", -apple-system, sans-serif;
  --font: ui-rounded, "SF Pro Rounded", -apple-system, BlinkMacSystemFont, "Segoe UI",
          "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Roboto, sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);

  --maxw: 1120px;
  --pad: clamp(20px, 5vw, 56px);
  --radius: 28px;
  --radius-lg: 40px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
  letter-spacing: -0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
:lang(zh) body, [lang="zh-Hans"] body { font-family: var(--font-cjk); letter-spacing: 0; }

img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
::selection { background: rgba(85, 171, 149, 0.22); }

/* —— 布局骨架 —— */
.wrap { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--pad); }
.section { padding-block: clamp(72px, 12vw, 148px); position: relative; }

/* —— 顶栏 —— */
.nav {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: saturate(1.4) blur(14px);
  -webkit-backdrop-filter: saturate(1.4) blur(14px);
  background: linear-gradient(to bottom, rgba(246, 251, 245, 0.86), rgba(246, 251, 245, 0.55));
  border-bottom: 1px solid rgba(228, 240, 225, 0.7);
}
.nav__row { display: flex; align-items: center; justify-content: space-between; gap: 16px; height: 68px; }
/* 品牌：图标 + 名称上下堆叠(主名 / 副名)，占用横向更少 */
.brand { display: inline-grid; grid-template-columns: auto auto; align-items: center; column-gap: 9px; font-weight: 700; color: var(--ink); white-space: nowrap; flex-shrink: 0; }
.brand [data-dong-mark] { grid-row: 1 / 3; display: flex; }
.brand .brand__mark { width: 32px; height: 32px; }
.brand [data-brand-main] { grid-column: 2; grid-row: 1; font-size: 17px; line-height: 1.12; }
.brand [data-brand-sub], .brand small { grid-column: 2; grid-row: 2; font-weight: 600; font-size: 11px; line-height: 1; color: var(--ink-3); letter-spacing: 0.03em; }
.nav__links { display: flex; align-items: center; gap: 22px; }
.nav__links a { font-size: 14.5px; color: var(--ink-2); font-weight: 500; transition: color .2s var(--ease); }
.nav__links a:hover { color: var(--accent-deep); }
@media (max-width: 720px) { .nav__links a:not(.btn) { display: none; } }

/* —— 语言切换 —— */
.lang {
  position: relative; font-size: 13.5px;
}
.lang__btn {
  display: inline-flex; align-items: center; gap: 6px; cursor: pointer;
  border: 1px solid var(--line); background: var(--card-soft); color: var(--ink-2);
  border-radius: 999px; height: 38px; padding: 0 14px; font: inherit; font-size: 14px; font-weight: 600;
  white-space: nowrap; flex-shrink: 0;
  transition: border-color .2s var(--ease), background .2s var(--ease);
}
/* 顶栏内的按钮统一高度，与语言切换对齐，且不换行 */
.nav__row .btn { height: 38px; padding: 0 18px; font-size: 14px; white-space: nowrap; flex-shrink: 0; }
.nav__row .btn--primary { color: #fff; }
@media (max-width: 720px) { .nav__links { gap: 12px; } .nav__row { gap: 10px; } }
.lang__btn:hover { border-color: #CDE6C8; }
.lang__btn svg { width: 15px; height: 15px; opacity: .7; }
.lang__menu {
  position: absolute; right: 0; top: calc(100% + 8px); width: 176px; max-height: 320px; overflow-y: auto;
  background: var(--card); border: 1px solid var(--line); border-radius: 18px;
  box-shadow: var(--shadow-card); padding: 6px; display: none; z-index: 60;
}
.lang.open .lang__menu { display: block; }
.lang__menu button {
  display: flex; width: 100%; align-items: center; justify-content: space-between; gap: 8px;
  background: none; border: 0; font: inherit; cursor: pointer; color: var(--ink);
  padding: 9px 12px; border-radius: 12px; text-align: start;
}
.lang__menu button:hover { background: var(--bg-2); }
.lang__menu button[aria-current="true"] { color: var(--accent-deep); font-weight: 700; }
.lang__menu button[aria-current="true"]::after { content: "✓"; }

/* —— 按钮 —— */
.btn {
  display: inline-flex; align-items: center; gap: 9px; justify-content: center;
  font-weight: 650; font-size: 15px; border-radius: 999px; cursor: pointer; border: 0;
  padding: 14px 26px; transition: transform .25s var(--ease), box-shadow .25s var(--ease), background .25s var(--ease);
  will-change: transform;
}
.btn--primary {
  color: var(--on-accent);
  background: linear-gradient(105deg, var(--grad-a), var(--grad-b));
  box-shadow: 0 14px 30px -10px rgba(85, 180, 161, 0.6);
}
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 22px 42px -12px rgba(85, 180, 161, 0.7); }
.btn--ghost { color: var(--accent-deep); background: var(--card); border: 1px solid var(--line); }
.btn--ghost:hover { transform: translateY(-2px); box-shadow: var(--shadow-soft); }
.btn svg { width: 18px; height: 18px; }

/* —— 文字层级 —— */
.eyebrow { display: inline-flex; align-items: center; gap: 8px; color: var(--accent-deep); font-weight: 650; font-size: 14px; }
.eyebrow::before { content: ""; width: 18px; height: 2px; border-radius: 2px; background: linear-gradient(90deg, var(--grad-a), var(--grad-b)); }
h1, h2, h3 { line-height: 1.12; letter-spacing: -0.03em; font-weight: 720; color: var(--ink); text-wrap: balance; }
.h-display { font-size: clamp(2.6rem, 6.4vw, 4.6rem); letter-spacing: -0.045em; }
.h-section { font-size: clamp(1.9rem, 4.2vw, 3rem); }
.lede { font-size: clamp(1.05rem, 2.1vw, 1.3rem); color: var(--ink-2); max-width: 40ch; line-height: 1.55; }
.muted { color: var(--ink-3); }

/* —— HERO —— */
.hero { position: relative; overflow: clip; }
.hero__sky {
  position: absolute; inset: 0; z-index: -2;
  background:
    radial-gradient(120% 90% at 78% 4%, rgba(145, 209, 76, 0.20), transparent 55%),
    radial-gradient(120% 90% at 8% 20%, rgba(85, 180, 161, 0.22), transparent 52%),
    linear-gradient(to bottom, var(--sky-top), var(--sky-bot) 62%, var(--bg));
}
.hero__blob { position: absolute; z-index: -1; filter: blur(46px); opacity: .5; }
.hero__grid { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 40px; align-items: center; padding-top: clamp(36px, 7vw, 80px); padding-bottom: clamp(60px, 9vw, 120px); }
@media (max-width: 860px) { .hero__grid { grid-template-columns: 1fr; text-align: center; gap: 8px; } .lede, .hero__cta { margin-inline: auto; } }
.hero__cta { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 30px; }
.hero__note { margin-top: 16px; font-size: 13.5px; color: var(--ink-3); }

/* 东东舞台 */
.stage { position: relative; display: grid; place-items: center; min-height: 420px; }
.stage__glow {
  position: absolute; width: 62%; aspect-ratio: 1; border-radius: 50%;
  background: radial-gradient(circle, rgba(133, 194, 144, 0.55), transparent 68%); filter: blur(10px);
}
.dongdong { width: min(300px, 74%); animation: breathe 5.5s var(--ease) infinite; transform-origin: 50% 92%; }
@keyframes breathe { 0%, 100% { transform: translateY(0) scale(1); } 50% { transform: translateY(-8px) scale(1.022); } }
@media (prefers-reduced-motion: reduce) { .dongdong { animation: none; } }

/* 漂浮的产品碎片 */
.chip {
  position: absolute; background: var(--card); border: 1px solid var(--line); border-radius: 18px;
  box-shadow: var(--shadow-float); padding: 12px 15px; display: flex; align-items: center; gap: 10px;
  font-size: 13.5px; color: var(--ink); font-weight: 600; animation: float 6s ease-in-out infinite;
}
.chip small { display: block; color: var(--ink-3); font-weight: 500; font-size: 11.5px; }
.chip .dot { width: 30px; height: 30px; border-radius: 10px; display: grid; place-items: center; flex: none; }
.chip--a { top: 8%; left: -6%; animation-delay: -1s; }
.chip--b { bottom: 12%; right: -8%; animation-delay: -3s; }
@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-12px); } }
@media (max-width: 860px) { .chip--a { left: 2%; } .chip--b { right: 2%; } }
@media (prefers-reduced-motion: reduce) { .chip { animation: none; } }

/* —— 特性区 —— */
.feature { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(28px, 6vw, 80px); align-items: center; }
.feature + .feature { margin-top: clamp(64px, 10vw, 128px); }
.feature--flip .feature__art { order: -1; }
@media (max-width: 820px) { .feature { grid-template-columns: 1fr; gap: 30px; } .feature--flip .feature__art { order: 0; } }
.feature__body h2 { margin-bottom: 16px; }
.feature__body p { color: var(--ink-2); font-size: 1.06rem; max-width: 46ch; }
.feature__list { list-style: none; margin-top: 22px; display: grid; gap: 13px; }
.feature__list li { display: flex; gap: 11px; align-items: flex-start; color: var(--ink-2); font-size: 0.98rem; }
.feature__list svg { width: 20px; height: 20px; flex: none; margin-top: 1px; }

/* 艺术卡：手机内的产品截景，用真实结构而非占位 */
.mock {
  position: relative; border-radius: 34px; padding: 22px;
  background: linear-gradient(160deg, var(--mint-a), var(--mint-b));
  box-shadow: var(--shadow-card);
}
.mock__inner { background: rgba(255,255,255,0.86); border: 1.5px solid rgba(255,255,255,0.9); border-radius: 22px; padding: 18px; }
.mock__title { font-size: 1.9rem; font-weight: 720; letter-spacing: -0.03em; position: relative; display: inline-block; }
.mock__title::after { content: ""; position: absolute; left: 0; right: 18%; bottom: 4px; height: 10px; background: linear-gradient(90deg, rgba(127,214,143,0.85), transparent); z-index: -1; border-radius: 4px; }
.mock__tags { color: var(--ink-2); font-size: 13px; margin-top: 8px; }
.mock__stats { display: flex; justify-content: space-between; margin-top: 18px; padding-top: 16px; border-top: 1px solid rgba(182,194,180,0.35); }
.mock__stats b { font-size: 1.15rem; font-weight: 700; }
.mock__stats span { display: block; font-size: 11.5px; color: var(--ink-3); font-weight: 500; }
.mock__perf { display: flex; justify-content: space-between; margin: 16px 2px 12px; }
.mock__perf i { width: 6px; height: 6px; border-radius: 50%; background: #C4D8C6; }
.mock__note { display: flex; gap: 8px; align-items: baseline; color: var(--accent-deep); font-weight: 600; font-size: 14px; }
.mock__body { color: var(--ink); font-size: 13.5px; line-height: 1.6; margin-top: 8px; }

/* 语音气泡波形 */
.bubbles { display: grid; gap: 12px; }
.bubble { max-width: 82%; padding: 11px 15px; border-radius: 16px; font-size: 14px; line-height: 1.5; }
.bubble--ai { background: #DCEDD6; color: var(--ink); border-bottom-left-radius: 5px; }
.bubble--me { background: linear-gradient(105deg, var(--grad-a), var(--grad-b)); color: #fff; margin-left: auto; border-bottom-right-radius: 5px; }
/* 三竖杠均匀跳动（音谱指示，克制不拥挤） */
.wave { display: inline-flex; align-items: center; gap: 4px; height: 18px; }
.wave i { width: 4px; height: 16px; border-radius: 3px; background: currentColor; opacity: .9; transform-origin: center; animation: eq 1.05s ease-in-out infinite; }
.wave i:nth-child(1){animation-delay:-.7s} .wave i:nth-child(2){animation-delay:-.35s} .wave i:nth-child(3){animation-delay:0s}
@keyframes eq { 0%,100%{transform:scaleY(.4)} 50%{transform:scaleY(1)} }
@media (prefers-reduced-motion: reduce){ .wave i{animation:none} }

/* —— 隐私安心带 —— */
.assure { background: linear-gradient(160deg, #F0F8EC, #E7F3E4); border-radius: var(--radius-lg); padding: clamp(30px, 5vw, 56px); border: 1px solid var(--line); }
.assure__grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; margin-top: 30px; }
@media (max-width: 720px){ .assure__grid{ grid-template-columns: 1fr; gap: 20px; } }
.assure__item h3 { font-size: 1.1rem; margin-bottom: 8px; display: flex; gap: 10px; align-items: center; }
.assure__item p { color: var(--ink-2); font-size: 0.96rem; }
.assure__item svg { width: 22px; height: 22px; flex: none; }

/* —— 下载 CTA —— */
.cta {
  text-align: center; border-radius: var(--radius-lg); padding: clamp(48px, 8vw, 92px) var(--pad);
  background:
    radial-gradient(90% 120% at 50% -10%, rgba(145,209,76,0.28), transparent 60%),
    linear-gradient(160deg, var(--grad-a), var(--grad-b));
  color: #fff; position: relative; overflow: clip;
}
.cta h2 { color: #fff; }
.cta p { color: rgba(255,255,255,0.9); max-width: 42ch; margin: 14px auto 0; }
.cta .btn--primary { background: #fff; color: var(--accent-deep); box-shadow: 0 18px 40px -12px rgba(0,0,0,0.28); margin-top: 30px; }
.cta .btn--primary:hover { box-shadow: 0 26px 52px -12px rgba(0,0,0,0.34); }
.cta__dong { width: 92px; margin: 0 auto 22px; filter: drop-shadow(0 12px 24px rgba(0,0,0,0.18)); }

/* —— 页脚 —— */
.foot { background: #16241C; color: #C9D8CC; padding-block: clamp(48px, 7vw, 74px); }
.foot a { color: #C9D8CC; opacity: .85; font-size: 14.5px; transition: opacity .2s; }
.foot a:hover { opacity: 1; color: #fff; }
.foot__grid { display: flex; flex-wrap: wrap; gap: 40px 64px; justify-content: space-between; }
.foot__brand { max-width: 30ch; }
.foot__brand .brand { color: #fff; }
.foot__brand p { color: #8FA595; font-size: 14px; margin-top: 14px; }
.foot__col h4 { color: #fff; font-size: 13px; letter-spacing: 0.04em; margin-bottom: 14px; opacity: .7; font-weight: 600; }
.foot__col ul { list-style: none; display: grid; gap: 10px; }
.foot__base { margin-top: 44px; padding-top: 24px; border-top: 1px solid rgba(255,255,255,0.08); display: flex; flex-wrap: wrap; gap: 12px 24px; justify-content: space-between; color: #7C9285; font-size: 13px; }

/* 移动端页脚：品牌整行 + 链接两列 + 联系整行(含长邮箱)，收紧空隙不浪费 */
@media (max-width: 640px) {
  .foot { padding-block: 44px 30px; }
  .foot__grid { display: grid; grid-template-columns: 1fr 1fr; gap: 26px 18px; }
  .foot__brand { grid-column: 1 / -1; }
  .foot__brand p { margin-top: 10px; }
  .foot__col:last-child { grid-column: 1 / -1; }
  .foot__col h4 { margin-bottom: 10px; }
  .foot__col ul { gap: 8px; }
  .foot__base { margin-top: 30px; gap: 6px; }
}

/* —— 文档页(协议/支持) —— */
.doc { background: var(--bg); }
.doc__hero { background: linear-gradient(to bottom, var(--sky-top), var(--bg)); padding-block: clamp(48px, 8vw, 92px) 0; }
.doc__hero h1 { font-size: clamp(2rem, 5vw, 3.1rem); }
.doc__meta { color: var(--ink-3); font-size: 14px; margin-top: 14px; }
.doc__layout { display: grid; grid-template-columns: 240px 1fr; gap: 48px; align-items: start; padding-block: clamp(40px, 6vw, 72px); }
@media (max-width: 880px){ .doc__layout{ grid-template-columns: 1fr; gap: 20px; } .doc__toc{ position: static !important; } }
.doc__toc { position: sticky; top: 88px; font-size: 14px; }
.doc__toc h4 { font-size: 12px; letter-spacing: 0.05em; color: var(--ink-3); margin-bottom: 12px; font-weight: 600; }
.doc__toc ol { list-style: none; display: grid; gap: 3px; counter-reset: t; }
.doc__toc a { display: block; padding: 7px 12px; border-radius: 10px; color: var(--ink-2); line-height: 1.35; transition: background .2s, color .2s; }
.doc__toc a:hover, .doc__toc a.active { background: var(--bg-2); color: var(--accent-deep); }
.doc__body { max-width: 72ch; }
.doc__body section { padding-block: 12px 26px; scroll-margin-top: 88px; }
.doc__body h2 { font-size: 1.4rem; margin-bottom: 14px; display: flex; gap: 12px; align-items: baseline; }
.doc__body h2 .n { color: var(--accent); font-weight: 700; font-size: 1rem; font-variant-numeric: tabular-nums; }
.doc__body h3 { font-size: 1.08rem; margin: 20px 0 8px; }
.doc__body p, .doc__body li { color: var(--ink-2); font-size: 1rem; line-height: 1.72; }
.doc__body p + p { margin-top: 12px; }
.doc__body ul { margin: 12px 0 12px 4px; display: grid; gap: 9px; list-style: none; }
.doc__body ul li { display: flex; gap: 10px; }
.doc__body ul li::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--mint-b); flex: none; margin-top: 9px; }
.doc__body a.inl { color: var(--accent-deep); font-weight: 600; text-decoration: underline; text-underline-offset: 2px; }
.callout { background: linear-gradient(150deg, #EEF7EA, #E6F2E3); border: 1px solid var(--line); border-radius: 18px; padding: 18px 20px; margin: 20px 0; color: var(--ink); font-size: 0.97rem; }
.callout strong { color: var(--accent-deep); }

/* 支持页 FAQ */
.faq { max-width: 760px; }
.faq details { border: 1px solid var(--line); border-radius: 18px; background: var(--card); margin-bottom: 12px; overflow: hidden; }
.faq summary { cursor: pointer; padding: 18px 22px; font-weight: 650; font-size: 1.05rem; list-style: none; display: flex; justify-content: space-between; gap: 12px; align-items: center; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--accent); font-size: 1.4rem; transition: transform .25s var(--ease); }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details p { padding: 0 22px 20px; color: var(--ink-2); line-height: 1.7; }

/* 进场动效：从已可见默认淡入上移，一次 */
.reveal { opacity: 0; transform: translateY(22px); }
.reveal.in { opacity: 1; transform: none; transition: opacity .9s var(--ease), transform .9s var(--ease); }
@media (prefers-reduced-motion: reduce){ .reveal{ opacity:1; transform:none; } }

.contact-card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 30px; box-shadow: var(--shadow-soft); max-width: 520px; }
.contact-card a { color: var(--accent-deep); font-weight: 700; font-size: 1.15rem; }