/* T013 · 世璟 LUCERNA 官网一期 · 静态站样式表
   规范：纯 CSS、移动端优先、断点 720px / 1080px、无框架无构建、无渐变与复杂动画 */

:root{
  --navy:#0B1F3A;   /* 主色：标题、按钮、页眉页脚 */
  --ivory:#FAF8F3;  /* 页面底色 */
  --green:#1F5C4A;  /* 仅用于成功提示、勾选状态 */
  --gold:#C9A961;   /* 仅用于 2-4px 品牌短线和深色底上的强调，不做大面积底色、不做正文字色 */
  --ink:#111; --ink2:#3A3A3C; --muted:#86868B; --line:#E3E1DA;
  --muted-strong:#59595E; /* 新增：小字号辅助文字，用于达到 WCAG AA；--muted 按规范保留，仅用于装饰 */
  --error:#A33A2B;
  /* 系统字体栈：无 Google Fonts / fonts.gstatic 外链；Inter 仅作优先名，缺则回退系统 */
  --font-sans:"Inter",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,"PingFang SC","Hiragino Sans GB","Noto Sans SC","Microsoft YaHei",sans-serif;
  --font-serif:"Noto Serif SC","Songti SC","SimSun",Georgia,"Times New Roman",serif;
  --maxw:1160px;
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0;background:var(--ivory);color:var(--ink);font-family:var(--font-sans);font-size:16px;line-height:1.8}
a{color:var(--navy);text-decoration:none}
a:hover{text-decoration:underline}
:focus-visible{outline:2px solid var(--navy);outline-offset:3px}
h1,h2,h3{margin:0;color:var(--navy);font-family:var(--font-serif);font-weight:600;line-height:1.35}
h1{font-size:2.05rem;letter-spacing:.01em}
h2{font-size:1.45rem}
h3{font-size:1.08rem}
p{margin:0 0 1em}
p:last-child{margin-bottom:0}
ul,ol{margin:0;padding:0;list-style:none}

.wrap{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 22px}
.section{padding:64px 0}
.section + .section{border-top:1px solid var(--line)}
.section-head{margin-bottom:30px}
.eyebrow{margin:0 0 14px;color:var(--muted-strong);font-size:.76rem;letter-spacing:.16em;text-transform:uppercase}
.rule{display:block;width:48px;height:3px;margin:0 0 22px;border:0;background:var(--gold)}
.lead{max-width:64ch;color:var(--ink2)}
.small{font-size:.875rem;color:var(--muted-strong)}
.todo{font-size:.8rem;color:var(--muted-strong)}

/* 页眉 */
.site-header{position:sticky;top:0;z-index:20;background:var(--ivory);border-bottom:1px solid var(--line)}
.header-inner{display:flex;align-items:center;gap:14px;min-height:66px}
.wordmark{display:inline-flex;align-items:center;margin-right:auto;color:var(--navy);white-space:nowrap}
.wordmark img{display:block;height:26px;width:auto;border:0}
.wordmark:hover{text-decoration:none}
.wordmark .latin{font-family:"Inter",var(--font-sans);font-weight:600;letter-spacing:.12em;font-size:1.02rem}
.wordmark .han{font-family:var(--font-serif);font-size:1.02rem}
.nav-toggle{display:inline-flex;align-items:center;justify-content:center;min-height:40px;padding:8px 14px;background:transparent;border:1px solid var(--muted-strong);color:var(--navy);font:inherit;font-size:.88rem;cursor:pointer}
.header-right{display:flex;align-items:center;gap:14px}
.lang{display:inline-flex;align-items:center;gap:6px;font-size:.85rem;white-space:nowrap}
.lang .sep{color:var(--muted)}
.lang [aria-current="page"]{font-weight:600;text-decoration:underline;text-underline-offset:4px}
.site-nav{display:none;position:absolute;left:0;right:0;top:100%;background:var(--ivory);border-bottom:1px solid var(--line);padding:10px 22px 18px}
.site-nav.is-open{display:flex;flex-direction:column;gap:2px}
.site-nav a{display:block;padding:10px 0;border-bottom:1px solid var(--line);font-size:.95rem}
.site-nav a:last-child{border-bottom:0}

/* 首屏 */
.hero{padding:64px 0}
.hero h1{max-width:20ch}
.hero .lead{margin-top:22px}
.entry-grid{display:grid;grid-template-columns:1fr;gap:18px;margin-top:38px}
.entry-card{display:flex;flex-direction:column;gap:14px;min-height:100%;padding:26px 22px 28px;background:#F3F0E8;border:1px solid var(--line)}
.entry-card .rule{margin:0 0 12px}
.entry-card .tag{margin:0;color:var(--muted-strong);font-size:.8rem;letter-spacing:.12em;text-transform:uppercase}
.entry-card h3{font-size:1.15rem}
.entry-card p{flex:1;color:var(--ink2)}
.btn{display:inline-block;min-height:46px;padding:12px 20px;background:var(--navy);border:1px solid var(--navy);color:#fff;font:inherit;font-size:.94rem;line-height:1.4;text-align:center;cursor:pointer}
.btn:hover{background:#12305A;border-color:#12305A;color:#fff;text-decoration:none}
.btn:focus-visible{outline:2px solid var(--navy);outline-offset:3px}

/* 服务流程 */
.steps{display:grid;grid-template-columns:1fr;margin-top:30px}
.step{padding:18px 0;border-top:1px solid var(--line)}
.step:first-child{border-top:0;padding-top:0}
.step .num{display:block;margin-bottom:8px;color:var(--muted-strong);font-family:"Inter",var(--font-sans);font-size:.78rem;letter-spacing:.14em}
.step h3{font-size:1.02rem;margin-bottom:6px}
.step p{color:var(--ink2);font-size:.94rem}

/* 买方 / 供应商服务 */
.two-col{display:grid;grid-template-columns:1fr;gap:26px;margin-top:30px}
.panel{padding:24px 22px;background:#F3F0E8;border:1px solid var(--line)}
.panel h3{margin-bottom:10px}
.panel p{color:var(--ink2)}

/* 质量与信任机制 */
.trust-list{display:grid;grid-template-columns:1fr;gap:0;margin-top:26px}
.trust-list li{padding:16px 0;border-top:1px solid var(--line)}
.trust-list li:first-child{border-top:0;padding-top:0}
.trust-list h3{font-size:1rem;margin-bottom:4px}
.trust-list p{color:var(--ink2);font-size:.94rem}
.asset-note{margin-top:24px;padding:18px 20px;border-left:3px solid var(--gold);background:#F3F0E8;color:var(--ink2);font-size:.94rem}

/* 表单 */
.form-grid{display:grid;grid-template-columns:1fr;gap:28px;margin-top:28px}
.form-card{padding:24px 20px 26px;background:#F3F0E8;border:1px solid var(--line)}
.form-card > h3{margin-bottom:6px}
.form-card > .form-intro{margin-bottom:22px;color:var(--ink2);font-size:.92rem}
form{margin:0}
.field{margin:0 0 17px;padding:0;border:0;min-width:0}
.field > label,.field > legend{display:block;margin:0 0 6px;padding:0;color:var(--ink);font-size:.9rem;font-weight:500}
.field .req{color:var(--error)}
.field .opt{color:var(--muted-strong);font-size:.82rem;font-weight:400}
.field input[type="text"],.field input[type="email"],.field input[type="tel"],.field select,.field textarea{
  display:block;width:100%;padding:10px 12px;background:#fff;border:1px solid var(--muted-strong);border-radius:0;
  color:var(--ink);font:inherit;font-size:.95rem;line-height:1.5
}
.field textarea{min-height:104px;resize:vertical}
.field select{background:#fff}
.field input::placeholder,.field textarea::placeholder{color:var(--muted-strong)}
.field [aria-invalid="true"]{border-color:var(--error)}
.field-error{margin:6px 0 0;color:var(--error);font-size:.85rem;line-height:1.5}
.field-error[hidden]{display:none}
.options{display:flex;flex-wrap:wrap;gap:8px 18px}
.options label{display:inline-flex;align-items:center;gap:8px;margin:0;font-size:.9rem;font-weight:400}
.options input[type="radio"],.options input[type="checkbox"],.consent input[type="checkbox"]{width:17px;height:17px;accent-color:var(--green);flex:0 0 auto}
.consent label{display:flex;align-items:flex-start;gap:10px;margin:0;font-size:.88rem;font-weight:400;line-height:1.6}
.consent input[type="checkbox"]{margin-top:4px}
.other-input{margin-top:10px}
.other-input label{font-size:.85rem;color:var(--ink2)}
.hp{position:absolute;left:-10000px;width:1px;height:1px;overflow:hidden}
.form-success,.form-failure{padding:16px 20px;background:#fff;font-size:.95rem}
.form-success{border-left:4px solid var(--green)}
.form-failure{border-left:4px solid var(--error);color:var(--error)}
.form-success[hidden],.form-failure[hidden]{display:none}

/* 页脚 */
.site-footer{background:var(--navy);color:#EDEAE2;padding:48px 0 40px}
.site-footer .rule{margin-bottom:20px}
.site-footer .wordmark{color:#fff;margin-bottom:14px}
.site-footer .wordmark img{height:26px}
.site-footer a{color:#EDEAE2}
.site-footer p{color:#EDEAE2;font-size:.9rem}
.footer-meta{display:flex;flex-wrap:wrap;gap:8px 22px;align-items:baseline;font-size:.88rem}
.site-footer .todo{color:#C9C4B8}

@media (min-width:720px){
  .section{padding:96px 0}
  .hero{padding:96px 0}
  .header-inner{min-height:78px}
  .nav-toggle{display:none}
  .site-nav{display:flex;position:static;flex-direction:row;gap:22px;padding:0;border:0;background:transparent}
  .site-nav a{padding:0;border:0;font-size:.9rem}
  h1{font-size:2.55rem}
  h2{font-size:1.7rem}
  .entry-grid{grid-template-columns:1fr 1fr;gap:22px}
  .two-col{grid-template-columns:1fr 1fr;gap:28px}
  .trust-list{grid-template-columns:1fr 1fr;column-gap:34px}
  .trust-list li:nth-child(2){border-top:0;padding-top:0}
  .form-card{padding:28px 26px 30px}
}

@media (min-width:1080px){
  .wrap{padding:0 32px}
  .steps{grid-template-columns:repeat(5,1fr)}
  .step{border-top:0;border-left:1px solid var(--line);padding:0 18px}
  .step:first-child{border-left:0;padding-left:0}
  .form-grid{grid-template-columns:1fr 1fr;gap:32px}
}

.footer-meta .sep{color:#C9C4B8;margin:0 .15em}
.section-head .eyebrow{margin-bottom:10px}