:root{--ink:#172033;--muted:#6f7788;--line:#e5e8ef;--bg:#f6f8fb;--blue:#2459d6;--nav:#172c4f;--green:#16794f;--red:#b42318;--shadow:0 18px 45px rgba(28,39,63,.08)}
*{box-sizing:border-box}body{margin:0;font-family:Inter,"PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--bg);line-height:1.6}a{color:var(--blue);text-decoration:none}button,input,select,textarea{font:inherit}.topbar{height:68px;padding:0 5vw;display:flex;align-items:center;justify-content:space-between;background:var(--nav);color:#fff;position:sticky;top:0;z-index:10}.brand{color:#fff;font-weight:800;font-size:20px;letter-spacing:.02em}.topbar nav{display:flex;gap:20px;align-items:center}.topbar nav a,.link-btn{color:#eaf0ff}.inline{display:inline}.link-btn{background:none;border:0;cursor:pointer}.btn{display:inline-flex;align-items:center;justify-content:center;border:0;border-radius:10px;padding:11px 18px;background:var(--blue);color:#fff;font-weight:700;cursor:pointer}.btn.small{padding:7px 12px}.btn.ghost{background:#fff;color:var(--blue)}.btn.ghost-dark{background:#fff;color:var(--ink);border:1px solid var(--line)}.btn.danger{background:#fff3f2;color:var(--red);border:1px solid #ffd5d2}.hero{max-width:1180px;margin:34px auto 0;padding:56px;border-radius:24px;background:linear-gradient(135deg,#1f51c7,#4d7fe9);color:#fff;display:grid;grid-template-columns:1.1fr .9fr;gap:44px;align-items:center;box-shadow:var(--shadow);overflow:hidden}.hero h1{font-size:44px;line-height:1.15;margin:10px 0 18px}.hero p{font-size:18px;color:#e8efff}.hero-image{width:100%;border-radius:18px;box-shadow:0 20px 50px rgba(0,0,0,.18)}.eyebrow{font-size:12px;font-weight:800;letter-spacing:.15em;color:#7f8aa3}.hero .eyebrow{color:#c9d8ff}.actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:24px}.container{max-width:1180px;margin:34px auto;padding:0 24px}.narrow{max-width:680px;margin:54px auto;padding:0 22px}.narrow.wide{max-width:860px}.section{max-width:1180px;margin:48px auto;padding:0 24px}.section.no-pad{padding:0;margin:34px 0}.section-head,.welcome-row{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;margin-bottom:20px}.section h2,.welcome-row h1{margin:2px 0}.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.card,.panel,.stat{background:#fff;border:1px solid var(--line);border-radius:16px;box-shadow:0 8px 28px rgba(28,39,63,.04)}.card{padding:24px}.card h3{margin:12px 0 8px}.study-card p{min-height:72px}.badge,.chip{display:inline-block;border-radius:999px;padding:4px 9px;background:#edf3ff;color:#315fbf;font-size:12px;font-weight:800}.chip{margin:2px 4px 2px 0}.meta,.muted,small{color:var(--muted)}.muted-light{color:#c5cee0}.text-link{font-weight:800}.panel{padding:28px}.auth-panel{margin-top:10vh}.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}.form-grid.one{grid-template-columns:1fr}.form-grid label{font-weight:700;font-size:14px}.form-grid input,.form-grid select,.form-grid textarea,.code-form input{display:block;width:100%;margin-top:7px;border:1px solid #d9deea;border-radius:10px;padding:11px 12px;background:#fff}.full{grid-column:1/-1}fieldset{border:1px solid var(--line);border-radius:12px;padding:18px}legend{font-weight:800}.check-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}.check{display:flex;gap:8px;align-items:center;font-weight:500!important}.check input{width:auto!important;margin:0!important}.code-panel{display:flex;gap:26px;align-items:center;justify-content:space-between}.code-form{display:flex;gap:10px;min-width:390px}.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-bottom:28px}.stat{padding:20px}.stat span{display:block;color:var(--muted);font-size:13px}.stat strong{font-size:28px}.small-strong{font-size:18px!important}.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin-bottom:28px}.key-values{display:grid;grid-template-columns:1fr 1fr;gap:10px 20px}.key-values span{color:var(--muted)}.table-wrap{overflow:auto;background:#fff;border:1px solid var(--line);border-radius:14px}table{border-collapse:collapse;width:100%;min-width:740px}th,td{text-align:left;padding:14px 16px;border-bottom:1px solid var(--line);vertical-align:top}th{font-size:12px;letter-spacing:.05em;color:#6c7487;background:#fafbfc}tr:last-child td{border-bottom:0}.status{display:inline-block;border-radius:999px;padding:4px 9px;background:#eef1f6;font-size:12px}.status.completed,.status.recruiting{background:#e9f7ef;color:var(--green)}.status.in_progress{background:#fff5dd;color:#935f00}.status.withdrawn,.status.closed{background:#fff0ef;color:var(--red)}.eligibility{padding:15px 17px;border-radius:12px;margin:22px 0}.eligibility.ok{background:#edf8f2;color:var(--green)}.eligibility.no{background:#fff1f0;color:var(--red)}.detail-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin:22px 0}.detail-grid>div{padding:15px;border-radius:12px;background:#f8fafc}.detail-grid span{display:block;color:var(--muted);font-size:12px}.detail-grid strong{display:block;margin-top:4px}.lead{font-size:17px}.flash{max-width:1180px;margin:16px auto;padding:13px 16px;border-radius:10px}.flash.success{background:#eaf8f0;color:#146c47}.flash.error{background:#fff0ef;color:#a3261e}.footer{text-align:center;color:#9299a8;font-size:12px;padding:44px 20px}.admin-login-page{padding-top:4vh}.adminbar{background:#132744}code{background:#f0f3f8;padding:2px 6px;border-radius:6px}@media(max-width:900px){.hero{margin:20px;grid-template-columns:1fr;padding:34px}.hero h1{font-size:34px}.cards{grid-template-columns:1fr}.stats{grid-template-columns:1fr 1fr}.grid-2,.form-grid,.detail-grid{grid-template-columns:1fr}.code-panel{display:block}.code-form{min-width:0;margin-top:15px}.topbar{height:auto;min-height:64px;align-items:flex-start;padding:16px 20px;gap:12px}.topbar nav{gap:10px;flex-wrap:wrap;justify-content:flex-end}.check-grid{grid-template-columns:1fr}}

/* v0.3 participant-facing refresh */
.public-topbar{background:#fff;color:var(--ink);border-bottom:1px solid var(--line);box-shadow:0 2px 14px rgba(28,39,63,.03)}
.public-topbar .brand{color:#10244a}.public-topbar nav a,.public-topbar .link-btn{color:#31415f}.public-topbar .btn.small{color:#fff}
.participant-hero{max-width:1180px;margin:28px auto 0;padding:38px 42px;border:1px solid #dce8fb;border-radius:24px;background:linear-gradient(135deg,#f8fbff 0%,#e9f3ff 100%);display:grid;grid-template-columns:.92fr 1.08fr;gap:34px;align-items:center;box-shadow:var(--shadow)}
.public-hero-copy h1{font-size:48px;line-height:1.12;margin:8px 0 16px;color:#102b5c}.public-hero-copy>p{font-size:18px;color:#52627e;max-width:560px}
.login-cta-card{margin-top:26px;padding:22px 24px;border-radius:18px;background:linear-gradient(135deg,#1764e8,#2f86f5);color:#fff;display:flex;align-items:center;justify-content:space-between;gap:20px;box-shadow:0 14px 30px rgba(34,100,220,.2)}
.login-cta-card strong{display:block;font-size:22px}.login-cta-card span{display:block;color:#dceaff;font-size:14px;margin-top:4px}.white-btn{background:#fff;color:#1764e8;white-space:nowrap}.white-btn:hover{background:#f4f8ff}
.hero-visual-wrap{display:grid;grid-template-columns:1fr 190px;gap:18px;align-items:center}.psychology-hero-image{width:100%;max-height:330px;object-fit:cover;border-radius:22px;border:1px solid #dce8fb}.qr-card{background:#fff;border:1px solid #dce8fb;border-radius:18px;padding:18px;text-align:center;box-shadow:0 8px 24px rgba(28,39,63,.05)}.qr-card strong{font-size:17px}.qr-card p{font-size:13px;color:var(--muted);margin:5px 0 12px}.qr-card small{display:block;color:#98a2b3;margin-top:8px;line-height:1.4}.qr-image{width:132px;height:132px;object-fit:contain;background:#fff;border-radius:12px}
.notice-strip{max-width:1180px;margin:26px auto 0;padding:20px 24px;background:#fffaf0;border:1px solid #f2dfb7;border-radius:16px;display:flex;gap:16px;align-items:flex-start}.notice-strip h2{font-size:18px;margin:0 0 4px}.notice-strip p{margin:0;color:#596579}.notice-icon{flex:0 0 30px;width:30px;height:30px;border-radius:50%;display:grid;place-items:center;background:#fff0c9;color:#a66300;font-weight:900}
.public-study-cards{grid-template-columns:repeat(3,1fr)}.public-study-card{display:flex;flex-direction:column}.public-study-card .study-button{margin-top:auto}.study-card-top{display:flex;align-items:center;justify-content:space-between;gap:12px}.reward{font-weight:900;color:#e45a27;background:#fff4eb;padding:5px 10px;border-radius:999px;font-size:14px}.reward.big{font-size:16px}.meta-row{display:flex;gap:14px;flex-wrap:wrap;color:var(--muted);font-size:13px;margin:8px 0 18px}.study-button{width:100%;margin-top:18px}.empty-state{grid-column:1/-1;text-align:center;color:var(--muted)}
.research-purpose{max-width:1180px;margin:8px auto 0;padding:22px 26px;border-radius:16px;background:linear-gradient(90deg,#edf5ff,#f7fbff);display:flex;align-items:center;gap:15px;border:1px solid #dfeafb}.research-purpose strong{font-size:18px;color:#174d9f}.research-purpose p{margin:2px 0;color:#64718a}.purpose-icon{width:38px;height:38px;border-radius:50%;background:#2468df;color:#fff;display:grid;place-items:center;font-weight:900}
.participation-notice{padding:18px 20px;border-radius:14px;background:#f5f9ff;border:1px solid #dce8fb;margin:18px 0 24px}.participation-notice h2{font-size:18px;margin:0 0 7px}.participation-notice p{margin:7px 0;color:#56657d}.participation-notice.compact{margin:20px 0}.participation-notice.compact p{margin-bottom:0}.consent-check{display:flex!important;align-items:flex-start;gap:10px!important;font-weight:500!important;padding:12px 14px;background:#fafbfc;border:1px solid var(--line);border-radius:10px}.consent-check input{width:auto!important;margin:4px 0 0!important}.soft-rule{border:0;border-top:1px solid var(--line);margin:28px 0}
.status.review-approved,.status.pay-paid{background:#e9f7ef;color:var(--green)}.status.review-pending,.status.pay-pending{background:#fff5dd;color:#935f00}.status.review-rejected{background:#fff0ef;color:var(--red)}.status.review-not_submitted,.status.pay-not_due{background:#eef1f6;color:#677185}
.status.scheduled{background:#edf3ff;color:#315fbf}.status.missed{background:#fff0ef;color:var(--red)}
.footer{margin-top:38px;border-top:1px solid var(--line);background:#fff;color:#58708f;padding:28px 20px}.footer strong{font-weight:700;color:#2e61b5}
@media(max-width:980px){.participant-hero{margin:20px;grid-template-columns:1fr;padding:30px}.hero-visual-wrap{grid-template-columns:1fr 180px}.public-study-cards{grid-template-columns:1fr}.notice-strip,.research-purpose{margin-left:20px;margin-right:20px}.public-hero-copy h1{font-size:38px}}
@media(max-width:620px){.participant-hero{padding:24px}.hero-visual-wrap{grid-template-columns:1fr}.qr-card{display:flex;align-items:center;text-align:left;gap:14px}.qr-card p{margin:2px 0}.qr-image{width:92px;height:92px}.login-cta-card{align-items:flex-start;flex-direction:column}.public-hero-copy h1{font-size:34px}.public-topbar nav a[href="/#studies"],.public-topbar nav a[href="/#notice"]{display:none}.notice-strip{margin-top:18px}.research-purpose{align-items:flex-start}}

/* v0.5 public navigation and cleaner landing page */
.brand-lockup{display:flex;align-items:center;gap:10px}.brand-name{font-size:22px;font-weight:900;letter-spacing:.08em;color:#10244a}.brand-subtitle{font-size:12px;font-weight:700;color:#7a879c;padding-left:10px;border-left:1px solid #d7deea;letter-spacing:.04em}.clean-public-hero{min-height:390px}.clean-public-hero .public-hero-copy{padding-right:8px}.public-studies-section{margin-top:42px}.register-panel{margin-top:5vh}.participation-notice p:last-child{margin-bottom:0}
@media(max-width:620px){.brand-lockup{gap:8px}.brand-name{font-size:20px}.brand-subtitle{font-size:11px;padding-left:8px}.clean-public-hero{min-height:0}.public-studies-section{margin-top:30px}}

/* v0.6 Qingyou brand */
.brand-lockup{gap:10px}.brand-logo{width:42px;height:42px;object-fit:contain;flex:0 0 auto}.brand-text-wrap{display:flex;align-items:center;gap:10px}.brand-name{color:#0b765d}.hero-brand-line{display:flex;align-items:center;gap:12px;margin-bottom:12px}.hero-brand-line img{width:54px;height:54px;object-fit:contain}.hero-brand-line>div{display:flex;flex-direction:column;line-height:1.15}.hero-brand-line strong{font-size:25px;color:#0b765d;letter-spacing:.08em}.hero-brand-line span{font-size:15px;color:#5c6b7f;margin-top:5px}.qingyou-full-logo{max-width:360px;width:100%;height:auto}
@media(max-width:620px){.brand-logo{width:36px;height:36px}.brand-text-wrap{display:block}.brand-subtitle{display:block;border-left:0;padding-left:0;margin-top:1px}.hero-brand-line img{width:46px;height:46px}.hero-brand-line strong{font-size:22px}}

/* v0.7 Qingyou public landing page */
.qingyou-topbar{height:72px;padding:0 max(28px,4.5vw);box-shadow:none;border-bottom:1px solid #edf1f5;position:sticky;top:0;background:rgba(255,255,255,.96);backdrop-filter:blur(12px)}
.qingyou-topbar .brand-logo{width:46px;height:46px}.qingyou-topbar .brand-name{font-size:22px;letter-spacing:.03em}.qingyou-topbar .brand-subtitle{font-size:14px;color:#26354d;font-weight:700;border-left:0;padding-left:0}.qingyou-topbar nav{gap:28px}.qingyou-topbar nav a,.qingyou-topbar .link-btn{font-weight:650;color:#27364e}.qingyou-topbar .home-nav-link{position:relative}.qingyou-topbar .home-nav-link.active{color:#087b5d}.qingyou-topbar .home-nav-link.active:after{content:"";position:absolute;height:2px;background:#168466;left:0;right:0;bottom:-22px;border-radius:2px}.qingyou-topbar .login-nav-btn{padding:8px 20px;border:1px solid #d9e1ec;border-radius:9px}.qingyou-topbar .register-nav-btn{padding:9px 20px;border-radius:9px;background:#1769df;box-shadow:0 6px 16px rgba(32,105,220,.18)}
.home-page{background:#fff;min-height:70vh;padding-bottom:12px}.qingyou-home-hero{min-height:470px;background:radial-gradient(circle at 8% 17%,rgba(84,205,190,.10) 0 52px,transparent 53px),radial-gradient(circle at 94% 25%,rgba(68,174,214,.10) 0 44px,transparent 45px),linear-gradient(112deg,#f7fffc 0%,#f4fbff 48%,#edf7ff 100%);display:grid;grid-template-columns:1.05fr .95fr;gap:54px;align-items:center;padding:42px max(48px,7vw);border-bottom:1px solid #e7f1f3;overflow:hidden}.qingyou-logo-stage{display:flex;justify-content:center;align-items:center;min-width:0}.qingyou-hero-logo{display:block;width:min(610px,100%);height:auto;filter:drop-shadow(0 20px 30px rgba(16,123,91,.08));transform:scale(1.05)}.qingyou-hero-copy{max-width:630px}.home-kicker{display:inline-block;font-size:12px;letter-spacing:.18em;font-weight:800;color:#5f8da2;margin-bottom:7px}.qingyou-hero-copy h1{font-size:50px;line-height:1.08;margin:2px 0 10px;color:#10324a;letter-spacing:-.02em}.platform-name{font-size:27px;color:#263f56;margin:0 0 7px;font-weight:600}.brand-slogan{font-size:22px;color:#0c9571;font-weight:800;margin:0}.hero-description{font-size:16px;color:#5d6e80;max-width:520px;margin:16px 0 0}.home-actions{display:flex;gap:16px;margin-top:25px}.home-primary-btn,.home-secondary-btn{min-width:142px;padding:13px 26px;border-radius:10px;font-size:16px}.home-primary-btn{background:#176be3;box-shadow:0 10px 24px rgba(23,107,227,.2)}.home-secondary-btn{background:#fff;color:#27374e;border:1px solid #bfcadc}.home-feature-row{display:grid;grid-template-columns:repeat(3,1fr);gap:15px;margin-top:30px}.home-feature-row>div{display:flex;align-items:flex-start;gap:9px}.feature-mark{flex:0 0 28px;width:28px;height:28px;border-radius:50%;background:#e9f8f1;color:#0f916a;display:grid;place-items:center;font-size:14px;font-weight:900}.home-feature-row strong{display:block;font-size:13px;color:#25364a}.home-feature-row small{display:block;font-size:11px;color:#7b8796;margin-top:1px;line-height:1.45}
.home-studies{max-width:1320px;margin:0 auto;padding:31px 46px 18px}.home-section-head{display:flex;align-items:center;justify-content:space-between;margin-bottom:18px}.home-section-head>div{display:flex;align-items:center;gap:10px}.home-section-head h2{font-size:22px;margin:0;color:#17293b}.home-section-head h2 small{font-size:14px;color:#7f8b99;font-weight:600}.section-dot{width:6px;height:22px;border-radius:10px;background:#18a66f}.home-section-head>a{font-size:13px;font-weight:700}.home-study-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.home-study-card{background:#fff;border:1px solid #dfe7ed;border-radius:14px;padding:12px;display:grid;grid-template-columns:150px minmax(0,1fr);gap:15px;box-shadow:0 5px 18px rgba(28,54,72,.055);min-height:190px;transition:transform .18s ease,box-shadow .18s ease}.home-study-card:hover{transform:translateY(-2px);box-shadow:0 10px 26px rgba(28,54,72,.09)}.home-study-image-wrap{height:100%;min-height:166px;border-radius:11px;overflow:hidden;background:#eef6f9}.home-study-image{width:100%;height:100%;object-fit:cover}.home-study-content{display:flex;flex-direction:column;min-width:0}.home-study-content h3{font-size:17px;line-height:1.35;margin:5px 0 5px;color:#16283a}.home-study-content>p{font-size:13px;line-height:1.55;color:#647384;margin:0;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}.home-study-meta{display:flex;gap:12px;flex-wrap:wrap;font-size:12px;color:#6f7e8d;margin-top:auto;padding-top:10px}.home-study-footer{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-top:9px}.home-reward{font-size:18px;color:#11935f}.home-study-btn{padding:8px 15px;border-radius:8px;font-size:13px;background:#176be3}.wechat-home-strip{max-width:1230px;margin:12px auto 0;padding:15px 34px;border:1px solid #dfe9ee;border-radius:14px;background:linear-gradient(90deg,#f7fffb,#f5fbff);display:grid;grid-template-columns:55px 1fr auto;align-items:center;gap:20px}.wechat-strip-icon{width:48px;height:48px;border-radius:50%;display:grid;place-items:center;background:#e8f8ef;color:#159665;font-size:25px;font-weight:800}.wechat-strip-copy strong{display:block;font-size:16px;color:#1f3345}.wechat-strip-copy span{display:block;font-size:12px;color:#768495;margin-top:2px}.wechat-qr-wrap{display:flex;align-items:center;gap:12px}.wechat-qr-wrap img{width:74px;height:74px;background:#fff;border-radius:7px}.wechat-qr-wrap small{max-width:92px;line-height:1.45;color:#8a96a4}.experiment-return-message{margin:0 0 22px;max-width:none}
.home-page+.footer{margin-top:0;border-top:1px solid #e5edf0;background:#f9fbfc;padding:20px}.home-page+.footer strong{color:#607487;font-weight:650}
@media(max-width:1120px){.qingyou-home-hero{grid-template-columns:1fr 1fr;padding:38px 46px;gap:30px}.qingyou-hero-copy h1{font-size:42px}.platform-name{font-size:23px}.home-study-grid{grid-template-columns:1fr 1fr}.home-study-card{grid-template-columns:140px 1fr}.qingyou-topbar nav{gap:18px}}
@media(max-width:820px){.qingyou-topbar{padding:0 20px}.qingyou-topbar .brand-subtitle{display:none}.qingyou-topbar .current-study-link{display:none}.qingyou-home-hero{grid-template-columns:1fr;padding:28px 28px 36px;text-align:center}.qingyou-logo-stage{order:0}.qingyou-hero-logo{width:min(500px,90%);transform:none}.qingyou-hero-copy{margin:0 auto}.qingyou-hero-copy h1{font-size:39px}.home-actions{justify-content:center}.home-feature-row{text-align:left}.home-studies{padding:28px 22px 14px}.home-study-grid{grid-template-columns:1fr}.wechat-home-strip{margin:12px 22px 0}.home-study-card{min-height:175px}}
@media(max-width:560px){.qingyou-topbar{min-height:64px;height:64px;align-items:center}.qingyou-topbar .brand-logo{width:38px;height:38px}.qingyou-topbar .brand-name{font-size:20px}.qingyou-topbar nav{gap:8px}.qingyou-topbar .home-nav-link{display:none}.qingyou-topbar .login-nav-btn{padding:7px 12px}.qingyou-topbar .register-nav-btn{padding:8px 12px}.qingyou-home-hero{padding:22px 18px 30px;gap:4px}.qingyou-hero-logo{width:min(420px,98%)}.home-kicker{display:none}.qingyou-hero-copy h1{font-size:34px}.platform-name{font-size:20px}.brand-slogan{font-size:18px}.hero-description{font-size:14px;margin-top:12px}.home-actions{gap:10px;margin-top:20px}.home-primary-btn,.home-secondary-btn{flex:1;min-width:0;padding:11px 16px}.home-feature-row{grid-template-columns:1fr;gap:9px;margin-top:22px}.home-feature-row>div{background:rgba(255,255,255,.62);border-radius:10px;padding:9px 11px}.home-studies{padding:25px 15px 10px}.home-section-head h2{font-size:19px}.home-section-head>a{display:none}.home-study-card{grid-template-columns:112px minmax(0,1fr);padding:10px;gap:11px;min-height:158px}.home-study-image-wrap{min-height:138px}.home-study-content h3{font-size:15px;margin-top:2px}.home-study-content>p{font-size:12px;-webkit-line-clamp:2}.home-study-meta{font-size:11px;gap:8px}.home-reward{font-size:16px}.home-study-btn{padding:7px 12px}.wechat-home-strip{margin:12px 15px 0;padding:14px 16px;grid-template-columns:42px 1fr}.wechat-strip-icon{width:40px;height:40px}.wechat-qr-wrap{grid-column:1/-1;justify-content:center;border-top:1px solid #e1eaee;padding-top:12px}.wechat-qr-wrap img{width:86px;height:86px}}


/* v0.8 landing page footer and QR refinements */
.wechat-home-strip{
  max-width:760px;
  margin:22px auto 0;
  padding:28px 30px 24px;
  border:1px solid #dfe9ee;
  border-radius:16px;
  background:linear-gradient(180deg,#fbfffd 0%,#f4fbff 100%);
  display:flex;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  gap:15px;
  text-align:center;
  box-shadow:0 6px 22px rgba(28,54,72,.045);
}
.wechat-strip-copy strong{display:block;font-size:18px;color:#1f3345}
.wechat-strip-copy span{display:block;font-size:13px;color:#768495;margin-top:4px}
.wechat-qr-wrap{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px}
.wechat-qr-wrap img{
  width:148px;
  height:148px;
  padding:5px;
  background:#fff;
  border:1px solid #e3e9ed;
  border-radius:10px;
  box-shadow:0 5px 16px rgba(25,58,76,.08);
}
.wechat-qr-wrap small{max-width:none;line-height:1.45;color:#7f8b99;font-size:12px}
.public-footer{
  margin-top:26px!important;
  border-top:1px solid #e5edf0!important;
  background:linear-gradient(180deg,#f5fbff 0%,#eef7fc 100%)!important;
  padding:24px 20px 20px!important;
  text-align:center;
}
.footer-privacy{display:flex;align-items:center;justify-content:center;gap:9px;color:#738398;font-size:13px}
.footer-privacy strong{color:#738398!important;font-weight:550!important}
.footer-shield{display:inline-grid;place-items:center;width:24px;height:24px;border:2px solid #8da0b5;border-radius:8px;color:#8093a8;font-size:11px;transform:rotate(45deg)}
.footer-shield::first-letter{transform:rotate(-45deg)}
.footer-copyright{margin-top:9px;color:#8a98aa;font-size:12px}
@media(max-width:620px){
  .wechat-home-strip{margin:16px 15px 0;padding:23px 18px 20px;gap:13px}
  .wechat-strip-copy strong{font-size:16px}
  .wechat-strip-copy span{font-size:12px}
  .wechat-qr-wrap{grid-column:auto;border-top:0;padding-top:0}
  .wechat-qr-wrap img{width:136px;height:136px}
  .footer-privacy{align-items:flex-start;font-size:12px;line-height:1.55}
  .footer-shield{flex:0 0 22px;width:22px;height:22px}
}

/* v0.9 centered side-by-side WeChat block + custom privacy icon */
.wechat-home-strip{
  max-width:980px;
  margin:24px auto 0;
  padding:24px 42px;
  display:flex;
  flex-direction:row;
  align-items:center;
  justify-content:center;
  gap:54px;
  text-align:left;
}
.wechat-strip-copy{
  flex:0 1 500px;
  text-align:left;
}
.wechat-strip-copy strong{
  font-size:18px;
  line-height:1.45;
}
.wechat-strip-copy span{
  font-size:13px;
  margin-top:6px;
  line-height:1.6;
}
.wechat-qr-wrap{
  flex:0 0 auto;
  display:flex;
  align-items:center;
  justify-content:center;
}
.wechat-qr-wrap img{
  width:174px;
  height:174px;
  padding:6px;
}
.footer-privacy-icon{
  width:25px;
  height:25px;
  object-fit:contain;
  flex:0 0 25px;
  opacity:.82;
}
.footer-shield{display:none!important}
@media(max-width:620px){
  .wechat-home-strip{
    margin:16px 15px 0;
    padding:22px 18px;
    flex-direction:column;
    gap:16px;
    text-align:center;
  }
  .wechat-strip-copy{flex:auto;text-align:center}
  .wechat-qr-wrap img{width:156px;height:156px}
  .footer-privacy-icon{width:23px;height:23px;flex-basis:23px}
}

/* v0.10 WeChat block alignment: match study section width, keep inner content compact */
.wechat-home-strip{
  max-width:1180px;
  width:calc(100% - 48px);
  margin:22px auto 0;
  padding:16px 28px;
  min-height:0;
  gap:0;
}
.wechat-home-strip .wechat-strip-copy{
  flex:0 1 430px;
  max-width:430px;
  margin-right:38px;
}
.wechat-home-strip .wechat-qr-wrap{
  flex:0 0 150px;
}
.wechat-home-strip .wechat-qr-wrap img{
  width:150px;
  height:150px;
  padding:4px;
}
@media(max-width:620px){
  .wechat-home-strip{
    width:calc(100% - 30px);
    margin:16px auto 0;
    padding:18px 16px;
    gap:12px;
  }
  .wechat-home-strip .wechat-strip-copy{
    max-width:360px;
    margin-right:0;
  }
  .wechat-home-strip .wechat-qr-wrap{
    flex-basis:auto;
  }
  .wechat-home-strip .wechat-qr-wrap img{
    width:140px;
    height:140px;
  }
}

.form-help{display:block;margin-top:6px;font-weight:500;color:var(--muted);line-height:1.45}


/* v0.12 experiment covers + participant navigation */
.participant-study-card{overflow:hidden;padding-top:14px}.participant-study-cover{width:100%;aspect-ratio:16/9;object-fit:cover;border-radius:12px;margin-bottom:15px;background:#edf4f6}.cover-picker-fieldset{padding:18px}.cover-picker-help{display:block;margin:0 0 14px}.cover-picker{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}.cover-option{position:relative;cursor:pointer;font-weight:600!important}.cover-option input{position:absolute;opacity:0;pointer-events:none}.cover-thumb-wrap{display:block;border:2px solid transparent;border-radius:12px;padding:3px;background:#fff;box-shadow:0 3px 12px rgba(32,48,65,.08);transition:.16s ease}.cover-thumb-wrap img{display:block;width:100%;aspect-ratio:16/9;object-fit:cover;border-radius:8px}.cover-label{display:block;margin-top:6px;text-align:center;color:#6e7a8a;font-size:12px}.cover-option input:checked + .cover-thumb-wrap{border-color:#15976e;box-shadow:0 0 0 3px rgba(21,151,110,.12)}.cover-option input:checked ~ .cover-label{color:#087b5d;font-weight:800}.eligibility-return-note{margin:10px 0 0}.participant-study-card .study-button{margin-top:auto}
@media(max-width:900px){.cover-picker{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(max-width:620px){.cover-picker{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.participant-study-cover{margin-bottom:12px}}

/* RDS dynamic experiment schema */
.schema-builder textarea{width:100%;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;line-height:1.55}
.schema-preview{margin-top:14px}.schema-preview table{margin:0}.schema-builder code{font-size:.92em}

/* v4 destructive admin actions */
.row-actions{display:flex;gap:12px;align-items:center;flex-wrap:wrap}.row-actions form{margin:0}.link-danger{border:0;background:none;padding:0;color:var(--red);cursor:pointer;font:inherit;font-weight:700}.link-danger:hover{text-decoration:underline}.compact-actions{margin-top:0;align-items:center}.compact-actions form{margin:0}.danger-note{padding:13px 15px;border-radius:10px;background:#fff3f2;color:var(--red);border:1px solid #ffd5d2}

/* ended experiments on public homepage */
.ended-studies{padding-top:18px;padding-bottom:42px}.ended-dot{background:#8a96a4}.ended-study-card{border-color:#e4e7eb;background:#fafbfc}.ended-study-card .home-study-image{filter:grayscale(.72);opacity:.82}.ended-study-badge{display:inline-flex;align-items:center;width:max-content;border-radius:999px;padding:4px 10px;background:#eef0f3;color:#697586;font-size:12px;font-weight:800}.ended-study-btn{background:#738092}.ended-study-btn:hover{background:#606c7c}.ended-experiment-panel{margin-top:8vh}.ended-experiment-panel h1{margin-top:14px}