/* ============================================================
   A-Z Beyond Limited LLC — 站点样式
   依赖 themes.css 提供的 CSS 变量
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

img, svg { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: var(--fw-head);
  color: var(--head-color);
  line-height: 1.25;
  margin: 0 0 .5em;
}
h1 { font-size: clamp(2rem, 4.6vw, 3.25rem); letter-spacing: -.02em; }
h2 { font-size: clamp(1.5rem, 3vw, 2.1rem); }
h3 { font-size: 1.2rem; }
p { margin: 0 0 .75em; }

.wrap { width: min(1160px, 92%); margin: 0 auto; }
.section { padding: clamp(1.8rem, 4.2vw, 3rem) 0; }
.section.alt { background: var(--alt); }
.center { text-align: center; }
.lead { font-size: 1.05rem; color: var(--text-muted); max-width: 62ch; }
.center .lead { margin-inline: auto; }
.eyebrow {
  font-size: .8rem; font-weight: 700; letter-spacing: .12em;
  text-transform: uppercase; color: var(--accent); margin-bottom: .35rem;
}
.section h2 { margin-bottom: .35rem; }
.section h2 + .lead, .section .center + .lead { margin-bottom: 1.1rem; }

/* ---------- Header ---------- */
header.site {
  position: sticky; top: 0; z-index: 60;
  background: var(--nav-bg);
  border-bottom: 1px solid var(--border);
}
header.site.scrolled { box-shadow: 0 2px 12px rgba(17, 24, 39, .1); }
.nav-bar { display: flex; align-items: center; gap: 1.5rem; height: 68px; }
.brand { display: flex; align-items: center; gap: .6rem; flex-shrink: 0; }
.brand img, .brand svg { height: 38px; width: auto; }

nav.main { margin-left: auto; display: flex; align-items: center; gap: 1.4rem; }
.nav-link {
  position: relative; color: var(--nav-text); font-size: .95rem;
  font-weight: 500; padding: .35rem 0; white-space: nowrap; text-decoration: none;
}
.nav-link::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -2px; height: 2px;
  background: var(--accent); transform: scaleX(0); transform-origin: left;
  transition: transform .22s ease;
}
.nav-link:hover::after, .nav-link.active::after { transform: scaleX(1); }
.nav-link:hover { text-decoration: none; }

.lang-switch {
  display: inline-flex; align-items: center; gap: .35rem;
  font-family: var(--font-body); font-size: .88rem; font-weight: 600;
  color: var(--nav-text); border: 1.5px solid var(--border);
  border-radius: 999px; padding: .4rem .9rem; white-space: nowrap; text-decoration: none;
  transition: border-color .2s ease, color .2s ease;
}
.lang-switch::before { content: "\2194"; font-size: .95rem; opacity: .75; }
.lang-switch:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }

.nav-cta { display: flex; align-items: center; gap: .75rem; margin-left: .5rem; }
.burger {
  display: none; margin-left: auto; background: none; border: 1px solid var(--border);
  border-radius: var(--radius); width: 42px; height: 38px; cursor: pointer; padding: 0;
}
.burger span {
  display: block; width: 20px; height: 2px; margin: 4px auto;
  background: var(--nav-text); border-radius: 2px;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  font-family: var(--font-body); font-size: .95rem; font-weight: 600;
  padding: .78rem 1.5rem; border-radius: var(--radius); border: 1.5px solid transparent;
  cursor: pointer; text-decoration: none; white-space: nowrap;
  transition: transform .18s ease, background-color .2s ease, box-shadow .2s ease;
}
.btn:hover { transform: translateY(-2px); text-decoration: none; }
.btn-primary { background: var(--brand); color: var(--brand-ink); }
.btn-primary:hover { box-shadow: var(--shadow); }
.btn-accent { background: var(--accent); color: var(--accent-ink); }
.btn-ghost { border-color: var(--border); color: var(--text); background: transparent; }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn-sm { padding: .55rem 1.05rem; font-size: .88rem; }

/* ---------- Hero ---------- */
.hero { position: relative; padding: clamp(1.8rem, 5vw, 3.4rem) 0; overflow: hidden; }
.hero::before {
  content: ""; position: absolute; inset: 0; background: var(--alt); z-index: -1;
}
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(1.5rem, 3.5vw, 2.5rem); align-items: center; }
.hero h1 { margin-bottom: .6rem; }
.hero .lead { font-size: 1.1rem; margin-bottom: 1.25rem; }
.hero-actions { display: flex; flex-wrap: wrap; gap: .9rem; }
.hero-art {
  border-radius: var(--radius-lg); overflow: hidden; box-shadow: var(--shadow);
  border: 1px solid var(--border); background: var(--surface);
}
.hero-art img { width: 100%; height: auto; }

/* ---------- 卡片 ---------- */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.1rem; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.1rem; }
.card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 1.3rem;
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--accent); }
.card h3 { margin-bottom: .4rem; }
.card p { color: var(--text-muted); margin-bottom: .6rem; }
.card-icon {
  width: 44px; height: 44px; border-radius: var(--radius);
  background: var(--alt); display: grid; place-items: center; margin-bottom: .7rem;
  font-size: 1.3rem;
}
.card-link { font-weight: 600; font-size: .92rem; }

/* ---------- 风格套餐 / 主题切换 ---------- */
.theme-picker { display: flex; flex-wrap: wrap; gap: .55rem; justify-content: center; margin-top: 1rem; }
.theme-chip {
  display: inline-flex; align-items: center; gap: .5rem; cursor: pointer;
  border: 1.5px solid var(--border); background: var(--surface);
  border-radius: 999px; padding: .45rem .95rem; font-size: .88rem; font-weight: 600;
  color: var(--text); transition: border-color .2s ease, transform .2s ease;
}
.theme-chip:hover { transform: translateY(-2px); border-color: var(--accent); }
.theme-chip.active { border-color: var(--accent); box-shadow: var(--shadow); }
.swatch { width: 16px; height: 16px; border-radius: 50%; border: 1px solid rgba(0,0,0,.12); }

/* ---------- 案例网格 ---------- */
.filters { display: flex; flex-wrap: wrap; gap: .5rem; justify-content: center; margin-bottom: 1.3rem; }
.filter-btn {
  border: 1px solid var(--border); background: transparent; color: var(--text-muted);
  border-radius: 999px; padding: .4rem 1rem; font-size: .88rem; cursor: pointer;
  font-family: var(--font-body); transition: all .2s ease;
}
.filter-btn.active, .filter-btn:hover { background: var(--brand); color: var(--brand-ink); border-color: var(--brand); }

.work-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.1rem; }
.work-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius-lg); overflow: hidden;
  transition: transform .22s ease, box-shadow .22s ease;
}
.work-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.work-shot { aspect-ratio: 16 / 10; overflow: hidden; background: var(--alt); }
.work-shot img { width: 100%; height: 100%; object-fit: cover; object-position: top center; }
.work-body { padding: 1rem 1.1rem 1.1rem; }
.tag {
  display: inline-block; font-size: .75rem; font-weight: 700; letter-spacing: .04em;
  text-transform: uppercase; color: var(--accent); margin-bottom: .5rem;
}
.work-body h3 { font-size: 1.08rem; margin-bottom: .4rem; }
.work-body p { font-size: .93rem; color: var(--text-muted); margin-bottom: .9rem; }

/* ---------- 流程步骤 ---------- */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; counter-reset: s; }
.step { position: relative; padding: 1.1rem 1.15rem 1.1rem 3.1rem; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); }
.step::before {
  counter-increment: s; content: counter(s);
  position: absolute; left: 1rem; top: 1.05rem;
  width: 28px; height: 28px; border-radius: 50%; background: var(--brand); color: var(--brand-ink);
  display: grid; place-items: center; font-size: .85rem; font-weight: 700;
}
.step h3 { font-size: 1.05rem; margin-bottom: .35rem; }
.step p { font-size: .93rem; color: var(--text-muted); margin: 0; }

/* ---------- FAQ ---------- */
.faq { max-width: 780px; margin: 0 auto; }
.faq details { border: 1px solid var(--border); border-radius: var(--radius); margin-bottom: .5rem; background: var(--surface); }
.faq summary { cursor: pointer; padding: .8rem 1rem; font-weight: 600; font-family: var(--font-head); color: var(--head-color); }
.faq details[open] summary { border-bottom: 1px solid var(--border); }
.faq .answer { padding: .75rem 1rem; color: var(--text-muted); }

.free-line {
  background: var(--alt); border-left: 3px solid var(--accent); border-radius: var(--radius);
  padding: .7rem .9rem; margin: .8rem 0;
}
.free-line strong { color: var(--head-color); }
ul.free-list { columns: 2; column-gap: 1.6rem; padding-left: 1.1rem; margin: 0; }
ul.free-list li { margin-bottom: .3rem; break-inside: avoid; font-size: .93rem; }
@media (max-width: 620px) { ul.free-list { columns: 1; } }

/* ---------- 表单 ---------- */
.form-card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: clamp(1.25rem, 2.4vw, 1.75rem); box-shadow: var(--shadow); }
.field { margin-bottom: .85rem; }
.field label { display: block; font-size: .88rem; font-weight: 600; margin-bottom: .4rem; }
.field input, .field select, .field textarea {
  width: 100%; font-family: var(--font-body); font-size: .96rem; color: var(--text);
  padding: .7rem .85rem; border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--bg);
}
.field input:focus, .field select:focus, .field textarea:focus {
  outline: 2px solid var(--accent); outline-offset: 1px; border-color: var(--accent);
}
.field textarea { min-height: 118px; resize: vertical; }
.field .err { display: none; color: #B91C1C; font-size: .82rem; margin-top: .3rem; }
.field.invalid input, .field.invalid textarea { border-color: #B91C1C; }
.field.invalid .err { display: block; }
.form-note { font-size: .84rem; color: var(--text-muted); margin-top: .75rem; }
.form-ok {
  display: none; margin-top: 1rem; padding: .9rem 1.1rem; border-radius: var(--radius);
  background: var(--alt); border: 1px solid var(--accent); font-weight: 600;
}
.form-ok.show { display: block; }

/* ---------- 联系信息 ---------- */
.contact-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: clamp(2rem, 4vw, 3.5rem); align-items: start; }
.contact-list { list-style: none; padding: 0; margin: 0; }
.contact-list li { padding: .6rem 0; border-bottom: 1px solid var(--border); display: flex; gap: .75rem; }
.contact-list li:last-child { border-bottom: none; }
.contact-list .k { font-weight: 600; min-width: 92px; color: var(--head-color); }

/* ---------- 页脚 ---------- */
footer.site { background: var(--footer-bg); color: var(--footer-text); padding: clamp(1.8rem, 3.4vw, 2.6rem) 0 1.1rem; margin-top: 0; }
footer.site h4 { color: var(--footer-text); font-size: 1rem; margin-bottom: .6rem; }
.foot-grid { display: grid; grid-template-columns: 1.4fr 1fr 1.2fr; gap: 1.8rem; }
footer.site p, footer.site li { color: var(--footer-muted); font-size: .93rem; }
footer.site a { color: var(--footer-text); }
footer.site ul { list-style: none; padding: 0; margin: 0; }
footer.site li { margin-bottom: .5rem; }
.foot-brand img, .foot-brand svg { height: 40px; width: auto; margin-bottom: 1rem; }
.socials { display: flex; gap: .6rem; margin-top: 1rem; }
.socials a {
  width: 36px; height: 36px; border-radius: 50%; display: grid; place-items: center;
  background: rgba(255,255,255,.1); color: var(--footer-text); font-size: .8rem; font-weight: 700;
}
.socials a:hover { background: var(--accent); color: var(--accent-ink); text-decoration: none; }
.foot-bottom {
  border-top: 1px solid rgba(255,255,255,.14); margin-top: 1.5rem; padding-top: .9rem;
  display: flex; flex-wrap: wrap; gap: 1rem; justify-content: space-between;
  font-size: .86rem; color: var(--footer-muted);
}

/* ---------- 语言 / 主题工具条 ---------- */
.util-bar { background: var(--alt); border-bottom: 1px solid var(--border); font-size: .85rem; }
.util-inner { display: flex; align-items: center; gap: 1rem; height: 40px; flex-wrap: wrap; }
.util-inner .spacer { margin-left: auto; }
.util-link { color: var(--text-muted); font-weight: 600; }
.util-link:hover { color: var(--accent); text-decoration: none; }
.util-label { color: var(--text-muted); }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .hero-grid, .contact-grid { grid-template-columns: 1fr; }
  .grid-3, .work-grid, .steps { grid-template-columns: repeat(2, 1fr); }
  .foot-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 860px) {
  .burger { display: block; }
  nav.main {
    display: none; position: absolute; top: 68px; left: 0; right: 0;
    background: var(--nav-bg); border-bottom: 1px solid var(--border);
    flex-direction: column; align-items: stretch; gap: 0; padding: .5rem 0;
    box-shadow: 0 8px 20px rgba(17,24,39,.12);
  }
  nav.main.open { display: flex; }
  nav.main .nav-link, nav.main .nav-cta { padding: .85rem 4%; }
  .nav-cta { flex-direction: column; align-items: stretch; margin-left: 0; }
}
@media (max-width: 620px) {
  .grid-3, .work-grid, .steps, .grid-2, .foot-grid { grid-template-columns: 1fr; }
  h1 { font-size: 2rem; }
}