/* ==========================================================================
   GVTL 官网样式 —— 金色品牌、金融信托稳重风格、响应式
   复用 trust-web 品牌色：#ab8855 / #c4a06e
   无外部图片/字体依赖：配图用 CSS 渐变 + 内联 SVG
   ========================================================================== */

:root {
  --gold: #ab8855;
  --gold-light: #c4a06e;
  --gold-dark: #8f6f3f;
  --ink: #2b3440;
  --ink-soft: #6b7280;
  --bg: #faf8f5;
  --bg-alt: #ffffff;
  --line: #e7e2da;
  --danger: #c0392b;
  --header-h: 72px;
  --maxw: 1160px;
  --shadow-sm: 0 1px 3px rgba(43, 52, 64, 0.08);
  --shadow-md: 0 8px 30px rgba(43, 52, 64, 0.12);
  --radius: 12px;
  --serif: Georgia, 'Times New Roman', 'Songti SC', 'Noto Serif CJK SC', serif;
  --sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
}

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 { font-family: var(--serif); font-weight: 600; line-height: 1.3; margin: 0 0 .5em; }
p { margin: 0 0 1em; }
a { color: var(--gold-dark); text-decoration: none; }
a:hover { color: var(--gold); }
img { max-width: 100%; display: block; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.container-narrow { max-width: 820px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block;
  padding: 12px 28px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  border: 1.5px solid transparent;
  transition: all .2s ease;
  text-align: center;
  font-family: var(--sans);
}
.btn-primary { background: var(--gold); color: #fff; border-color: var(--gold); }
.btn-primary:hover { background: var(--gold-dark); border-color: var(--gold-dark); color: #fff; }
.btn-outline { background: transparent; color: var(--gold-dark); border-color: var(--gold-light); }
.btn-outline:hover { background: var(--gold); color: #fff; border-color: var(--gold); }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-h);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--line);
  z-index: 100;
  transition: box-shadow .2s ease;
}
.site-header.scrolled { box-shadow: var(--shadow-sm); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 100%; gap: 16px; }
.brand { display: flex; align-items: center; }
.brand-logo { height: 40px; width: auto; }

.main-nav { display: flex; align-items: center; gap: 28px; }
.main-nav > a { color: var(--ink); font-size: 15px; font-weight: 500; position: relative; }
.main-nav > a:not(.btn):hover { color: var(--gold); }
.main-nav > .btn-login { padding: 8px 20px; font-size: 14px; }

.header-tools { display: flex; align-items: center; gap: 12px; }
.lang-select {
  appearance: none;
  padding: 8px 30px 8px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background-color: #fff;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 10px center;
  font-size: 14px;
  color: var(--ink);
  cursor: pointer;
}

/* 汉堡按钮 */
.menu-toggle { display: none; flex-direction: column; justify-content: center; gap: 5px; width: 40px; height: 40px; background: none; border: 0; cursor: pointer; padding: 0; }
.menu-toggle span { display: block; width: 24px; height: 2px; background: var(--ink); margin: 0 auto; transition: all .25s ease; border-radius: 2px; }
.menu-toggle[aria-expanded='true'] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-toggle[aria-expanded='true'] span:nth-child(2) { opacity: 0; }
.menu-toggle[aria-expanded='true'] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  margin-top: var(--header-h);
  padding: 96px 0 112px;
  color: #fff;
  background:
    radial-gradient(circle at 80% 20%, rgba(196, 160, 110, 0.35), transparent 45%),
    linear-gradient(135deg, #1f2a36 0%, #2b3a4a 60%, #243140 100%);
  text-align: center;
  overflow: hidden;
}
.hero::after {
  content: '';
  position: absolute; left: 0; right: 0; bottom: 0; height: 6px;
  background: linear-gradient(90deg, var(--gold-dark), var(--gold-light), var(--gold-dark));
}
.hero-inner { position: relative; z-index: 1; max-width: 820px; }
.hero-eyebrow { letter-spacing: 3px; text-transform: uppercase; font-size: 13px; color: var(--gold-light); margin-bottom: 16px; }
.hero-title { font-size: clamp(32px, 5vw, 52px); margin-bottom: 20px; }
.hero-subtitle { font-size: clamp(15px, 2vw, 18px); color: #d7dde4; max-width: 640px; margin: 0 auto 36px; }
.hero-cta { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero .btn-outline { color: #fff; border-color: rgba(255,255,255,.5); }
.hero .btn-outline:hover { background: rgba(255,255,255,.12); border-color: #fff; color: #fff; }

/* ---------- 通用区块 ---------- */
.section { padding: 84px 0; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 48px; }
.section-head h2 { font-size: clamp(26px, 3.5vw, 36px); color: var(--ink); }
.section-head h2::after { content: ''; display: block; width: 56px; height: 3px; background: var(--gold); margin: 16px auto 0; border-radius: 2px; }
.section-subtitle { color: var(--ink-soft); font-size: 17px; margin: 0; }

/* 关于我们 */
.about-text { max-width: 820px; margin: 0 auto 32px; font-size: 17px; color: var(--ink); text-align: center; }
.badges { list-style: none; display: flex; flex-wrap: wrap; justify-content: center; gap: 14px; padding: 0; margin: 0; }
.badges li { padding: 10px 22px; border: 1px solid var(--gold-light); border-radius: 999px; color: var(--gold-dark); font-size: 14px; font-weight: 600; background: rgba(171,136,85,.06); }

/* ---------- 服务卡片 ---------- */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 40px 32px;
  box-shadow: var(--shadow-sm);
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: var(--gold-light); }
.card-icon { width: 64px; height: 64px; border-radius: 50%; background: rgba(171,136,85,.1); color: var(--gold); display: flex; align-items: center; justify-content: center; margin-bottom: 22px; }
.card h3 { font-size: 21px; color: var(--ink); }
.card p { color: var(--ink-soft); margin: 0; font-size: 15px; }
.card p + p { margin-top: 10px; } /* 协作卡两段文字 */

/* ---------- FAQ 手风琴 ---------- */
.faq-list { display: flex; flex-direction: column; gap: 14px; }
.faq-item { border: 1px solid var(--line); border-radius: var(--radius); background: #fff; overflow: hidden; }
.faq-question {
  width: 100%; text-align: left; background: none; border: 0; padding: 20px 24px;
  font-size: 16px; font-weight: 600; color: var(--ink); cursor: pointer;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  font-family: var(--sans);
}
.faq-question:hover { color: var(--gold-dark); }
.faq-icon { position: relative; flex: 0 0 18px; width: 18px; height: 18px; }
.faq-icon::before, .faq-icon::after { content: ''; position: absolute; background: var(--gold); border-radius: 2px; transition: all .25s ease; }
.faq-icon::before { top: 50%; left: 0; right: 0; height: 2px; transform: translateY(-50%); }
.faq-icon::after { left: 50%; top: 0; bottom: 0; width: 2px; transform: translateX(-50%); }
.faq-item.open .faq-icon::after { opacity: 0; transform: translateX(-50%) rotate(90deg); }
.faq-item.open .faq-question { color: var(--gold-dark); }
.faq-answer { display: grid; grid-template-rows: 0fr; transition: grid-template-rows .3s ease; }
.faq-answer > p { overflow: hidden; margin: 0; padding: 0 24px; color: var(--ink-soft); }
.faq-item.open .faq-answer { grid-template-rows: 1fr; }
.faq-item.open .faq-answer > p { padding-bottom: 22px; }

/* ---------- 联系我们 ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1.4fr; gap: 56px; align-items: start; }
.contact-info { margin: 0; }
.contact-info > div { padding: 18px 0; border-bottom: 1px solid var(--line); }
.contact-info > div:first-child { padding-top: 0; }
.contact-info dt { font-size: 13px; color: var(--ink-soft); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 6px; }
.contact-info dd { margin: 0; font-size: 17px; color: var(--ink); font-weight: 500; word-break: break-word; }

.contact-form .form-row { margin-bottom: 18px; }
.contact-form label { display: block; font-size: 14px; font-weight: 600; color: var(--ink); margin-bottom: 6px; }
.contact-form input, .contact-form textarea {
  width: 100%; padding: 12px 14px; border: 1px solid var(--line); border-radius: 8px;
  font-size: 15px; font-family: var(--sans); color: var(--ink); background: #fff; transition: border-color .2s, box-shadow .2s;
}
.contact-form input:focus, .contact-form textarea:focus { outline: none; border-color: var(--gold); box-shadow: 0 0 0 3px rgba(171,136,85,.15); }
.contact-form input.invalid, .contact-form textarea.invalid { border-color: var(--danger); }
.contact-form .btn { margin-top: 6px; width: 100%; }
.form-feedback { min-height: 1.5em; margin: 12px 0 0; font-size: 14px; color: var(--gold-dark); }
.form-feedback.error { color: var(--danger); }

/* ---------- Footer ---------- */
.site-footer { background: #1c2530; color: #c7ced6; padding: 60px 0 28px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1.4fr; gap: 40px; padding-bottom: 36px; border-bottom: 1px solid rgba(255,255,255,.08); }
.footer-brand .brand-logo { height: 40px; margin-bottom: 14px; filter: brightness(0) invert(1); }
.footer-brand p { color: #9aa4af; font-size: 14px; max-width: 320px; }
.footer-col h4 { color: #fff; font-size: 16px; margin-bottom: 16px; }
.footer-col ul { list-style: none; padding: 0; margin: 0; }
.footer-col li { margin-bottom: 10px; font-size: 14px; color: #9aa4af; }
.footer-col a { color: #9aa4af; }
.footer-col a:hover { color: var(--gold-light); }
.footer-bottom { padding-top: 24px; }
.footer-bottom .disclaimer { font-size: 12px; color: #7d8794; margin-bottom: 8px; }
.footer-bottom .copyright { font-size: 13px; color: #9aa4af; margin: 0; }

/* ---------- 风格切换浮标（三向，临时预览辅助，选定风格后移除） ---------- */
.style-switch {
  position: fixed;
  right: 16px; bottom: 16px;
  z-index: 200;
  display: flex; flex-direction: column; gap: 4px;
  padding: 8px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.94);
  box-shadow: var(--shadow-md);
}
.style-switch a, .style-switch span {
  display: inline-flex; align-items: center; gap: 7px;
  padding: 6px 12px;
  border-radius: 7px;
  font-size: 12px; font-weight: 600;
  color: var(--ink-soft);
  white-space: nowrap;
  transition: background .15s ease, color .15s ease;
}
.style-switch a:hover { background: rgba(171,136,85,.08); color: var(--gold-dark); }
.style-switch span {
  background: rgba(171, 136, 85, 0.12);
  color: var(--gold-dark);
  box-shadow: inset 0 0 0 1px rgba(171, 136, 85, 0.35);
}
.style-switch span::before, .style-switch a::before {
  content: '';
  width: 5px; height: 5px;
  border-radius: 50%;
  background: currentColor;
  opacity: .9;
}
.style-switch span::before { background: var(--gold); box-shadow: 0 0 6px rgba(171,136,85,.6); }

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width: 900px) {
  .cards { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; gap: 36px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 860px) {
  /* 移动端导航：汉堡菜单 */
  .menu-toggle { display: flex; }
  .main-nav {
    position: fixed;
    top: var(--header-h); left: 0; right: 0;
    flex-direction: column; align-items: stretch;
    background: #fff;
    padding: 16px 24px 24px;
    gap: 6px;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow-md);
    transform: translateY(-130%);
    transition: transform .3s ease;
    z-index: 99;
  }
  .main-nav.open { transform: translateY(0); }
  .main-nav > a:not(.btn) { padding: 12px 4px; border-bottom: 1px solid var(--line); }
  .main-nav > .btn-login { margin-top: 10px; text-align: center; }
  .hero { padding: 64px 0 80px; }
  .section { padding: 64px 0; }
}

@media (max-width: 560px) {
  .footer-grid { grid-template-columns: 1fr; }
  .container { padding: 0 18px; }
  .hero-cta { flex-direction: column; align-items: stretch; }
  .hero-cta .btn { width: 100%; }
}