@charset "UTF-8";
/* ============================================================
   妙答 AI 客户官网 · 样式表 v25
   深绿主视觉 / Bento 功能区 / 教程卡片库 / 浅色内容区
   ============================================================ */
:root{
  --ink:#14332f;           /* 主文字：深墨绿 */
  --ink-2:#274a45;         /* 次级文字 */
  --muted:#6b7f79;         /* 说明文字 */
  --green:#0e7a63;         /* 品牌绿 */
  --green-deep:#0a5b4a;    /* 深绿 */
  --mint:#d9f5e6;          /* 浅薄荷 */
  --mint-soft:#eaf7ee;     /* 更浅薄荷 */
  --line:#e2eae3;          /* 描边 */
  --white:#ffffff;
  --bg:#f5f8f4;            /* 页面底色 */
  --card:#ffffff;
  --hero-top:#0e443c;      /* 主视觉深绿（上） */
  --hero-bottom:#082824;   /* 主视觉深绿（下） */
  --radius:18px;
  --shadow-sm:0 4px 14px rgba(20,51,47,.06);
  --shadow-md:0 14px 34px rgba(20,51,47,.12);
  --shadow-lg:0 26px 60px rgba(8,32,28,.35);
  --sans:"Microsoft YaHei","PingFang SC","Hiragino Sans GB",system-ui,sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:96px}
body{margin:0;color:var(--ink);background:var(--bg);font:15px/1.75 var(--sans);-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
button,input{font:inherit}
button,a{touch-action:manipulation}
button{cursor:pointer}
button:disabled{opacity:.4;cursor:default}
img{max-width:100%}
svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.7;flex:none}
:focus-visible{outline:3px solid #2ba98a;outline-offset:4px;border-radius:4px}
.container{width:min(1200px,calc(100% - 48px));margin:auto}
.skip{position:absolute;left:-9999px;top:0;background:var(--green);color:#fff;padding:10px 18px;border-radius:0 0 10px 0;z-index:100}
.skip:focus{left:0}

/* ================= 顶部导航 ================= */
.header{position:fixed;inset:0 0 auto;z-index:50;background:rgba(245,248,244,.94);border-bottom:1px solid var(--line);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);transition:background .3s,border-color .3s}
.header.at-top{background:transparent;border-bottom-color:transparent}
.header.at-top .nav{color:#e9f6ee}
.header.at-top .brand i{border-left-color:rgba(255,255,255,.28);color:rgba(233,246,238,.72)}
.header.at-top nav a{color:rgba(233,246,238,.82)}
.header.at-top nav a:hover{color:#ffffff}
.header.at-top .menu-toggle span{background:#e9f6ee}
.nav{display:flex;align-items:center;justify-content:space-between;min-height:72px;gap:24px;transition:color .3s}
.brand{display:flex;align-items:center;gap:9px;white-space:nowrap}
.brand img{object-fit:contain;border-radius:9px}
.brand strong{font-size:23px;letter-spacing:-1px}
.brand strong span{font-size:20px;font-weight:500;letter-spacing:0}
.brand i{font-size:11px;letter-spacing:1px;font-style:normal;color:var(--muted);border-left:1px solid #cddcd3;margin-left:9px;padding-left:15px;transition:border-color .3s,color .3s}
#main-nav{display:flex;gap:34px;font-size:14.5px;color:var(--ink-2)}
#main-nav a{transition:color .2s}
#main-nav a:hover{color:var(--green)}
.nav-actions{display:flex;align-items:center;gap:14px}

/* 按钮 */
.button{display:inline-flex;align-items:center;justify-content:center;gap:11px;border:1px solid #c8d9cf;border-radius:11px;padding:12px 21px;font-weight:600;background:#fff;color:var(--ink);transition:transform .2s,box-shadow .2s,background .2s,border-color .2s;white-space:nowrap}
.button:hover{transform:translateY(-2px);background:#e9f6ec;border-color:#a9cdb6}
.button.primary{background:linear-gradient(135deg,#129173,#0a5f4c);border-color:transparent;color:#fff;padding:15px 26px;font-size:15.5px;box-shadow:0 10px 26px rgba(10,95,76,.32)}
.button.primary:hover{background:linear-gradient(135deg,#0e8268,#08513f);box-shadow:0 14px 30px rgba(10,95,76,.38)}
.button.compact{font-size:13px;padding:9px 16px;border-radius:9px}
.text-link{display:inline-flex;align-items:center;gap:12px;font-size:14px;font-weight:600;color:var(--green)}
.text-link span{transition:transform .2s}
.text-link:hover span{transform:translateX(3px)}
.text-link.on-dark{color:#bfeed8}
.text-link.on-dark:hover{color:#ffffff}
.play-mini{display:inline-flex;align-items:center;justify-content:center;width:26px;height:26px;border-radius:50%;background:rgba(255,255,255,.14);border:1px solid rgba(255,255,255,.35);font-size:10px}

/* 汉堡菜单 */
.menu-toggle{display:none;flex-direction:column;justify-content:center;gap:5px;width:42px;height:42px;padding:10px;background:transparent;border:1px solid transparent;border-radius:9px}
.menu-toggle span{display:block;height:2px;background:var(--ink);border-radius:2px;transition:transform .25s,opacity .25s}
.menu-toggle.open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.menu-toggle.open span:nth-child(2){opacity:0}
.menu-toggle.open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* ================= 首屏主视觉 ================= */
.hero{position:relative;overflow:hidden;background:radial-gradient(120% 130% at 12% -10%,#155a4e 0%,var(--hero-top) 38%,var(--hero-bottom) 100%);color:#e9f6ee;padding:172px 0 96px}
.hero-decor{position:absolute;inset:0;pointer-events:none}
.glow{position:absolute;border-radius:50%;filter:blur(70px)}
.glow-a{width:520px;height:520px;right:-120px;top:-160px;background:rgba(64,201,150,.22)}
.glow-b{width:420px;height:420px;left:-140px;bottom:-180px;background:rgba(26,110,96,.55)}
.grid-dots{position:absolute;inset:0;background-image:radial-gradient(rgba(255,255,255,.14) 1px,transparent 1px);background-size:26px 26px;mask-image:radial-gradient(70% 60% at 60% 40%,#000 0%,transparent 100%);-webkit-mask-image:radial-gradient(70% 60% at 60% 40%,#000 0%,transparent 100%)}
.hero-grid{position:relative;display:grid;grid-template-columns:1.02fr 1fr;gap:64px;align-items:center}
.eyebrow{display:inline-flex;align-items:center;gap:9px;font-size:12px;font-weight:600;letter-spacing:2.5px;color:var(--green)}
.eyebrow.on-dark{color:#8fe0bd}
.status-dot{width:8px;height:8px;border-radius:50%;background:#34d39b;box-shadow:0 0 0 0 rgba(52,211,155,.55);animation:pulse 2.4s infinite}
@keyframes pulse{0%{box-shadow:0 0 0 0 rgba(52,211,155,.5)}70%{box-shadow:0 0 0 9px rgba(52,211,155,0)}100%{box-shadow:0 0 0 0 rgba(52,211,155,0)}}
.hero h1{margin:20px 0 18px;font-size:clamp(34px,4.4vw,54px);line-height:1.22;letter-spacing:-1px;font-weight:700}
.hero h1 em{font-style:normal;background:linear-gradient(92deg,#8ff0c4 10%,#eafbf1 55%,#9fe8cc 90%);-webkit-background-clip:text;background-clip:text;color:transparent}
.lead{margin:0;font-size:16.5px;line-height:1.9;color:rgba(233,246,238,.86)}
.hero-contact{display:inline-flex;align-items:center;gap:8px;margin:18px 0 0;padding:8px 18px;border-radius:999px;background:rgba(143,240,196,.12);border:1px solid rgba(143,240,196,.4);color:#8ff0c4;font-size:14px;font-weight:600;letter-spacing:.5px}
.hero-actions{display:flex;align-items:center;gap:24px;margin:32px 0 18px;flex-wrap:wrap}
.download-meta{margin:6px 0 0;font-size:13px;color:rgba(233,246,238,.62)}
.download-feedback{min-height:22px;margin:4px 0 0;font-size:13px;color:#9fe8cc}
.hero-stats{display:flex;gap:0;list-style:none;margin:26px 0 0;padding:22px 0 0;border-top:1px solid rgba(255,255,255,.14)}
.hero-stats li{display:flex;flex-direction:column;padding:0 30px;border-left:1px solid rgba(255,255,255,.14)}
.hero-stats li:first-child{padding-left:0;border-left:none}
.hero-stats b{font-size:22px;letter-spacing:-.5px}
.hero-stats span{font-size:12.5px;color:rgba(233,246,238,.6);margin-top:2px}

/* 首屏右侧：产品截图 */
.hero-visual{position:relative}
.app-frame{background:#fff;border-radius:16px;overflow:hidden;box-shadow:var(--shadow-lg);border:1px solid rgba(255,255,255,.14)}
.frame-bar{display:flex;align-items:center;gap:7px;padding:12px 16px;background:#f1f6f1;border-bottom:1px solid #e4ece5}
.frame-bar i{width:11px;height:11px;border-radius:50%}
.frame-bar i:nth-child(1){background:#f6a5a5}
.frame-bar i:nth-child(2){background:#f6d78a}
.frame-bar i:nth-child(3){background:#9fd8b6}
.frame-bar span{margin-left:10px;font-size:12.5px;color:var(--muted)}
.app-frame img{display:block;width:100%;height:auto}
.float-card{position:absolute;display:flex;align-items:center;gap:12px;background:rgba(255,255,255,.97);border:1px solid #e6efe7;border-radius:14px;padding:13px 16px;box-shadow:var(--shadow-md);animation:floaty 6s ease-in-out infinite}
.float-card strong{display:block;font-size:13.5px;color:var(--ink);line-height:1.4}
.float-card small{display:block;font-size:11.5px;color:var(--muted);margin-top:2px}
.float-a{top:-26px;left:-34px;animation-delay:0s}
.float-b{top:38%;right:-38px;animation-delay:-2s}
.float-c{bottom:-24px;left:16%;animation-delay:-4s}
.float-card span{display:flex;align-items:center;justify-content:center;width:34px;height:34px;border-radius:10px;font-size:15px;flex:none}
.check-icon{background:var(--mint);color:var(--green-deep)}
.spark{background:#eef2ff;color:#4f63c4}
.gear{background:#fdeee2;color:#c07a3a}
@keyframes floaty{0%,100%{transform:translateY(0)}50%{transform:translateY(-9px)}}
.visual-footnote{position:absolute;left:0;right:0;bottom:-40px;text-align:center;font-size:12px;color:rgba(233,246,238,.55)}

/* ================= 能力条 ================= */
.capability-strip{background:#eaf3e9;border-top:1px solid #dcead9;border-bottom:1px solid #dcead9}
.capability-strip .container{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:17px 0;flex-wrap:wrap}
.strip-lead{font-size:13.5px;color:var(--muted)}
.strip-items{display:flex;align-items:center;gap:18px;font-size:15px;color:var(--ink-2);flex-wrap:wrap}
.strip-items strong{font-weight:600}
.strip-items i{font-style:normal;color:#b6c9ba}

/* ================= 通用章节 ================= */
.section{padding:96px 0}
.section-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:36px;margin-bottom:44px;flex-wrap:wrap}
.section-heading h2{margin:14px 0 0;font-size:clamp(26px,3vw,36px);line-height:1.3;letter-spacing:-.5px}
.section-heading p{margin:14px 0 0;color:var(--muted);font-size:14.5px}
.outline-label{font-size:13px;color:var(--green);border:1px solid #bfdcc6;background:#fff;border-radius:999px;padding:8px 18px;white-space:nowrap}

/* ================= 产品功能 Bento ================= */
.features-grid{display:grid;grid-template-columns:repeat(12,1fr);grid-auto-rows:auto;gap:20px}
.feature{display:flex;flex-direction:column;gap:14px;background:var(--card);border:1px solid var(--line);border-radius:20px;padding:30px;transition:transform .25s,box-shadow .25s,border-color .25s}
.feature:hover{transform:translateY(-4px);box-shadow:var(--shadow-md);border-color:#c8e0cb}
.feature.featured{grid-column:1/8;grid-row:1/3;padding:40px;gap:30px}
.feature:nth-child(2){grid-column:8/13}
.feature:nth-child(3){grid-column:8/13}
.feature:nth-child(4){grid-column:1/5}
.feature:nth-child(5){grid-column:5/9}
.feature:nth-child(6){grid-column:9/13}
.feature-no{font-size:12px;letter-spacing:2px;color:var(--green);font-weight:600}
.feature h3{margin:0;font-size:21px;line-height:1.42;letter-spacing:-.3px}
.feature p{margin:0;color:var(--muted);font-size:14px;line-height:1.8}
.feature .text-link{margin-top:auto;padding-top:14px}
.feature-symbol{display:flex;align-items:center;justify-content:center;width:44px;height:44px;border-radius:13px;background:var(--mint-soft);border:1px solid #d5ecdb;color:var(--green-deep);font-size:19px}
.featured .feature-copy{max-width:520px}
.featured h3{font-size:clamp(22px,2.4vw,30px)}
.featured p{font-size:15px}
.feature-shot{margin-top:auto;border:1px solid var(--line);border-radius:14px;overflow:hidden;background:#f2f7f2;box-shadow:var(--shadow-sm)}
.feature-shot img{display:block;width:100%;height:auto}

/* ================= 视频课堂 ================= */
.learning-section{background:linear-gradient(180deg,var(--bg) 0%,#edf4ea 100%);border-top:1px solid #e7efe4}
.start-path{display:flex;align-items:center;gap:12px;flex-wrap:wrap;background:#fff;border:1px solid var(--line);border-radius:16px;padding:18px 24px;margin-bottom:20px}
.start-path>div{display:flex;align-items:center;gap:14px;margin-right:10px}
.path-tag{font-size:11px;letter-spacing:1.5px;color:var(--green-deep);background:var(--mint);border-radius:999px;padding:4px 11px;font-weight:600;white-space:nowrap}
.start-path strong{font-size:14.5px}
.start-path a{display:inline-flex;align-items:center;gap:10px;border:1px solid #d3e2d3;border-radius:999px;padding:8px 16px;font-size:13.5px;font-weight:600;background:#fbfdf9;transition:border-color .2s,background .2s,transform .2s}
.start-path a:hover{border-color:var(--green);background:#eef8ef;transform:translateY(-2px)}
.start-path a b{display:inline-flex;align-items:center;justify-content:center;width:26px;height:26px;border-radius:50%;background:var(--mint);color:var(--green-deep);font-size:12px}
.start-path a span{color:#a2b6a8;font-size:12px}
.prerequisites{display:grid;grid-template-columns:1.1fr 1fr 1fr;gap:17px;padding:26px;border:1px solid #c4dcc4;background:linear-gradient(135deg,#e2f1de,#ebf6e5);border-radius:18px;margin-bottom:34px}
.prerequisites h3{font-size:17px;margin:10px 0 6px}
.prerequisites p{font-size:12.5px;color:#64806c;margin:0;max-width:280px}
.prerequisites>a{display:flex;flex-direction:column;gap:8px;background:#fafdf8;border:1px solid #d5e7d3;border-radius:12px;padding:18px;transition:transform .2s,box-shadow .2s,border-color .2s}
.prerequisites>a:hover{transform:translateY(-3px);border-color:#7fae8b;box-shadow:var(--shadow-sm)}
.prerequisites b{color:#4e8a63;font-size:10.5px;font-weight:500;letter-spacing:.5px;display:flex;justify-content:space-between;align-items:center}
.prerequisites b span{font-size:9px;color:#7ba082}
.prerequisites strong{font-size:13.5px;font-weight:600;line-height:1.5}
.prerequisites small{font-size:11px;color:#8aa191;line-height:1.6}
.library-tools{display:flex;align-items:center;justify-content:space-between;gap:18px;margin-bottom:16px;flex-wrap:wrap}
.filters{display:flex;gap:9px;flex-wrap:wrap}
.filter{border:1px solid var(--line);background:#fff;color:var(--ink-2);border-radius:999px;padding:8px 17px;font-size:13.5px;font-weight:500;transition:background .2s,color .2s,border-color .2s}
.filter:hover{border-color:var(--green);color:var(--green)}
.filter[aria-pressed="true"]{background:var(--green);border-color:var(--green);color:#fff}
.search{display:flex;align-items:center;gap:9px;background:#fff;border:1px solid var(--line);border-radius:999px;padding:9px 18px;min-width:290px;transition:border-color .2s,box-shadow .2s}
.search:focus-within{border-color:var(--green);box-shadow:0 0 0 4px rgba(14,122,99,.1)}
.search svg{color:var(--muted);width:17px;height:17px}
.search input{border:none;outline:none;background:transparent;flex:1;font-size:13.5px;color:var(--ink)}
.search input::placeholder{color:#9fb2a6}
.library-caption{display:flex;justify-content:space-between;font-size:13px;color:var(--muted);margin-bottom:16px}
.lesson-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(258px,1fr));gap:22px}
.lesson-card{display:flex;flex-direction:column;background:#fff;border:1px solid var(--line);border-radius:16px;overflow:hidden;transition:transform .25s,box-shadow .25s,border-color .25s}
.lesson-card:hover{transform:translateY(-5px);box-shadow:var(--shadow-md);border-color:#c4dcc6}
.lesson-cover{position:relative;aspect-ratio:16/9;overflow:hidden;background:#0f2f2a}
.lesson-cover img{width:100%;height:100%;object-fit:cover;display:block;transition:transform .4s}
.lesson-card:hover .lesson-cover img{transform:scale(1.05)}
.cover-play{position:absolute;inset:0;margin:auto;display:flex;align-items:center;justify-content:center;width:52px;height:52px;border-radius:50%;background:rgba(255,255,255,.92);color:var(--green-deep);font-size:15px;box-shadow:0 6px 20px rgba(0,0,0,.3);transition:transform .25s}
.lesson-card:hover .cover-play{transform:scale(1.08)}
.lesson-time{position:absolute;right:10px;bottom:10px;background:rgba(8,30,26,.78);color:#fff;font-size:11.5px;border-radius:7px;padding:2px 8px}
.lesson-body{display:flex;flex-direction:column;gap:8px;padding:16px 18px 18px;flex:1}
.lesson-body small{font-size:11.5px;letter-spacing:1px;color:var(--green)}
.lesson-body h3{margin:0;font-size:15.5px;line-height:1.5;font-weight:600}
.lesson-body>span{margin-top:auto;padding-top:12px;border-top:1px solid #eef3ee;display:flex;justify-content:space-between;font-size:12.5px;color:var(--muted)}
.lesson-body>span i{font-style:normal;color:var(--green);font-weight:600}
.no-results{display:flex;flex-direction:column;align-items:center;gap:14px;padding:56px 20px;color:var(--muted);font-size:14.5px;text-align:center}
.lesson-note{margin-top:30px;text-align:center;font-size:12.5px;color:#93a89b}
.lesson-note,noscript p{color:#93a89b}
noscript p{font-size:13px}

/* ================= 常见问题 ================= */
.faq-section{display:grid;grid-template-columns:1fr 1.3fr;gap:56px;align-items:start}
.faq-head{position:sticky;top:112px}
.faq-head h2{margin:14px 0 12px;font-size:clamp(26px,3vw,36px);line-height:1.3;letter-spacing:-.5px}
.faq-head p{color:var(--muted);font-size:14.5px;margin:0}
.faq-list details{background:#fff;border:1px solid var(--line);border-radius:14px;margin-bottom:12px;overflow:hidden;transition:border-color .2s,box-shadow .2s}
.faq-list details[open]{border-color:#bfdcc6;box-shadow:var(--shadow-sm)}
.faq-list summary{position:relative;list-style:none;padding:17px 48px 17px 22px;font-weight:600;font-size:15px;cursor:pointer}
.faq-list summary::-webkit-details-marker{display:none}
.faq-list summary::after{content:"+";position:absolute;right:20px;top:50%;transform:translateY(-50%);width:26px;height:26px;border-radius:50%;background:var(--mint-soft);border:1px solid #d5ecdb;color:var(--green-deep);display:flex;align-items:center;justify-content:center;font-size:16px;transition:transform .25s,background .25s}
.faq-list details[open] summary::after{content:"−";background:var(--green);color:#fff;border-color:var(--green);transform:translateY(-50%) rotate(180deg)}
.faq-list summary:hover{color:var(--green)}
.faq-list details p{padding:0 22px 18px;margin:0;color:var(--muted);font-size:14px;line-height:1.85}
.faq-list details .text-link{margin:0 22px 18px}

/* ================= 下载 CTA ================= */
.download-section{padding:40px 0 96px}
.cta-panel{position:relative;overflow:hidden;display:grid;grid-template-columns:1.15fr .85fr;align-items:center;gap:44px;background:radial-gradient(120% 150% at 85% -20%,#155a4e 0%,var(--hero-top) 42%,var(--hero-bottom) 100%);border-radius:26px;padding:58px 64px;color:#e9f6ee}
.cta-panel::after{content:"";position:absolute;width:430px;height:430px;right:-140px;bottom:-220px;border-radius:50%;background:rgba(64,201,150,.18);filter:blur(60px);pointer-events:none}
.cta-copy h2{margin:14px 0 10px;font-size:clamp(26px,3vw,38px);letter-spacing:-.5px}
.cta-copy p{margin:0;color:rgba(233,246,238,.82);font-size:15px}
.download-side{position:relative;z-index:1;display:flex;flex-direction:column;align-items:flex-start;gap:12px}
.button.cta{background:#fff;border-color:#fff;color:var(--green-deep);padding:17px 32px;font-size:16.5px;border-radius:13px;box-shadow:0 14px 34px rgba(0,0,0,.28)}
.button.cta:hover{background:#eaf9ef;border-color:#eaf9ef}
.download-side>span{font-size:13px;color:rgba(233,246,238,.66)}
.download-side .download-feedback{color:#9fe8cc}

/* ================= 页脚 ================= */
.footer{display:flex;align-items:center;justify-content:space-between;gap:18px;padding:30px 0 38px;border-top:1px solid var(--line);color:var(--muted);font-size:13.5px;flex-wrap:wrap}
.footer .brand strong{font-size:19px}
.footer .brand strong span{font-size:17px}
.footer a:last-child{color:var(--green);font-weight:600}
.footer a:last-child:hover{color:var(--green-deep)}

/* ================= 视频弹窗 ================= */
.modal-open{overflow:hidden}
#lesson-dialog{width:min(1080px,calc(100% - 32px));max-height:92dvh;border:none;border-radius:18px;padding:0;background:#fbfdf9;overflow:hidden;box-shadow:var(--shadow-lg);color:var(--ink)}
#lesson-dialog::backdrop{background:rgba(6,20,17,.62);backdrop-filter:blur(5px);-webkit-backdrop-filter:blur(5px)}
.dialog-top{position:sticky;top:0;z-index:2;display:flex;align-items:center;justify-content:space-between;gap:18px;padding:16px 22px;background:#fbfdf9;border-bottom:1px solid var(--line)}
.dialog-top h2{margin:4px 0 0;font-size:18px;line-height:1.4}
.dialog-top .eyebrow{font-size:11px;letter-spacing:1.5px}
.icon-button{width:38px;height:38px;border-radius:50%;border:1px solid var(--line);background:#fff;font-size:21px;line-height:1;color:var(--ink-2);display:flex;align-items:center;justify-content:center;transition:background .2s,border-color .2s}
.icon-button:hover{background:var(--mint-soft);border-color:var(--green)}
.player-layout{display:grid;grid-template-columns:1fr 296px}
.player-main{padding:20px;min-width:0;overflow:auto;max-height:calc(92dvh - 82px)}
.player-main video{display:block;width:100%;max-height:calc(92dvh - 250px);border-radius:12px;background:#000}
.player-controls{display:flex;align-items:center;justify-content:space-between;gap:14px;margin-top:16px}
.player-controls .button{padding:9px 18px;font-size:13.5px}
#player-info{font-size:13px;color:var(--muted)}
#video-error{padding:12px 14px;border-radius:10px;background:#fdf1ec;border:1px solid #f3d3c4;color:#9a4a2a;font-size:13.5px;margin:12px 0 0}
#video-error a{color:var(--green);font-weight:600;text-decoration:underline;margin-left:6px}
.player-disclaimer{margin:16px 0 0;padding-top:12px;border-top:1px dashed #d8e3d8;font-size:12px;color:#93a89b}
.chapters{padding:20px 16px 20px 20px;background:#f1f6f0;border-left:1px solid var(--line);overflow:auto;max-height:calc(92dvh - 82px)}
.chapters h3{margin:0;font-size:15px}
.chapters>p{margin:4px 0 14px;font-size:12px;color:var(--muted)}
.chapter{display:flex;align-items:flex-start;gap:10px;width:100%;text-align:left;background:#fff;border:1px solid #e2ece2;border-radius:10px;padding:10px 12px;margin-bottom:8px;font-size:13px;line-height:1.5;color:var(--ink-2);transition:border-color .2s,background .2s}
.chapter:hover{border-color:#b3d6ba}
.chapter b{flex:none;font-size:11.5px;font-weight:600;color:var(--green-deep);background:var(--mint);border-radius:6px;padding:1px 7px;margin-top:1px}
.chapter.playing{background:var(--mint-soft);border-color:var(--green)}
.chapter.playing b{background:var(--green);color:#fff}

/* ================= 响应式 ================= */
@media (max-width:1024px){
  .hero{padding-top:140px}
  .hero-grid{grid-template-columns:1fr;gap:84px}
  .hero-copy{max-width:640px}
  .hero-visual{max-width:620px;margin:0 auto}
  .feature.featured{grid-column:1/-1;grid-row:auto}
  .feature:nth-child(2),.feature:nth-child(3){grid-column:span 6}
  .feature:nth-child(4),.feature:nth-child(5),.feature:nth-child(6){grid-column:span 6}
  .faq-section{grid-template-columns:1fr;gap:34px}
  .faq-head{position:static}
  .cta-panel{grid-template-columns:1fr;gap:30px;padding:46px 40px}
  .float-a{left:6px}
  .float-b{right:0}
}
@media (max-width:800px){
  html{scroll-padding-top:76px}
  .nav{min-height:64px}
  .brand i{display:none}
  #main-nav{position:fixed;top:64px;left:0;right:0;display:flex;flex-direction:column;gap:0;background:#fff;border-bottom:1px solid var(--line);box-shadow:var(--shadow-md);padding:8px 20px 16px;transform:translateY(-10px);opacity:0;visibility:hidden;transition:opacity .22s,transform .22s,visibility .22s}
  #main-nav.open{transform:none;opacity:1;visibility:visible}
  #main-nav a{padding:13px 2px;font-size:16px;color:var(--ink);border-bottom:1px solid #f0f4ef}
  #main-nav a:last-child{border-bottom:none}
  .nav-actions .button.compact{display:none}
  .menu-toggle{display:flex}
  .hero{padding:124px 0 76px}
  .hero-grid{gap:76px}
  .hero-actions{flex-direction:column;align-items:stretch}
  .hero-actions .text-link{justify-content:center}
  .hero-stats li{padding:0 18px}
  .float-card{padding:10px 12px;border-radius:11px}
  .float-card strong{font-size:12.5px}
  .float-card small{font-size:10.5px}
  .float-a{top:-18px;left:2px}
  .float-b{top:auto;bottom:34%;right:0}
  .float-c{bottom:-16px;left:4px}
  .visual-footnote{bottom:-32px}
  .capability-strip .container{justify-content:center;text-align:center}
  .section{padding:68px 0}
  .section-heading{flex-direction:column;align-items:flex-start;gap:12px;margin-bottom:32px}
  .prerequisites{grid-template-columns:1fr 1fr;padding:20px}
  .prerequisites>div{grid-column:1/-1}
  .feature:nth-child(2),.feature:nth-child(3),.feature:nth-child(4),.feature:nth-child(5),.feature:nth-child(6){grid-column:1/-1}
  .feature.featured{padding:26px}
  .feature{padding:24px}
  .search{min-width:0;width:100%}
  .library-tools{align-items:stretch;flex-direction:column}
  .cta-panel{padding:38px 26px;border-radius:20px}
  .footer{justify-content:center;text-align:center}
  .player-layout{grid-template-columns:1fr}
  .chapters{border-left:none;border-top:1px solid var(--line);max-height:38dvh}
  .player-main{max-height:none}
}
@media (max-width:520px){
  .container{width:calc(100% - 36px)}
  .hero{padding-top:112px}
  .hero h1{font-size:33px}
  .lead{font-size:15px}
  .hero-stats{flex-wrap:wrap;gap:14px 0}
  .hero-stats li{border-left:none;padding:0 20px 0 0}
  .prerequisites{grid-template-columns:1fr}
  .start-path a{padding:7px 13px;font-size:12.5px}
  .download-section{padding-bottom:64px}
  .download-side{align-items:stretch}
  .download-side .button{width:100%}
}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation:none!important;transition:none!important}
  html{scroll-behavior:auto}
}