:root{
  --brand:#2b71ff;
  --text:#0b1220;
  --muted:#6a7280;
  --line:#e9edf3;
}

/* 主区 */
.ft{
  border-top:1px solid var(--line);
  background:#fff;
}
.ft-inner{
  max-width:1200px;
  margin:0 auto;
  padding:28px 20px 36px;
}
.ft-grid{
  display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));
  gap:24px 56px;
  align-items:start;
}

/* 列标题与链接 */
.ft-heading{
  margin:0 0 12px;
  font-size:18px;
  font-weight:700;
  color:#222;
}
.ft-list{ list-style:none; margin:0; padding:0; }
.ft-link{
  display:inline-block;
  padding:8px 0;
  color:#555;
  text-decoration:none;
  transition:color .15s ease;
}
.ft-link:hover{ color:var(--brand); }

/* 订阅表单 */
.ft-subscribe{
  display:flex;
  align-items:center;
  gap:10px;
}
.ft-input{
  flex:1;
  min-width:0;
  height:40px;
  padding:0 14px;
  border:1px solid #dde3ee;
  border-radius:999px;
  background:#fff;
  font-size:14px;
  color:#223;
  outline:none;
  transition:border-color .15s ease, box-shadow .15s ease;
}
.ft-input::placeholder{ color:#9aa3b5; }
.ft-input:focus{
  border-color:var(--brand);
  box-shadow:0 0 0 3px rgba(43,113,255,.15);
}

.ft-btn{
  height:40px;
  padding:0 18px;
  border:none;
  border-radius:999px;
  background:var(--brand);
  color:#fff;
  font-weight:700;
  cursor:pointer;
  transition:background .15s ease, transform .05s ease, box-shadow .15s ease;
}
.ft-btn:hover{ background:#1f63ff; }
.ft-btn:active{ transform:translateY(1px); }
.ft-btn:focus-visible{ outline:none; box-shadow:0 0 0 3px rgba(43,113,255,.25); }

/* 版权条 */
.ft-bar{
  background:#fafbfc;
  border-top:1px solid var(--line);
}
.ft-bar-inner{
  max-width:1200px;
  margin:0 auto;
  padding:14px 20px;
  font-size:13px;
  color:#666;
}
.ft-copy{ line-height:1.7; }
.ft-addr{ margin-left:6px; }
.ft-bar-link{ color:#5b6bff; text-decoration:none; }
.ft-bar-link:hover{ text-decoration:underline; }

/* 无障碍隐藏文字 */
.sr-only{
  position:absolute !important;
  width:1px; height:1px;
  padding:0; margin:-1px;
  overflow:hidden; clip:rect(0,0,0,0);
  white-space:nowrap; border:0;
}

/* 响应式 */
@media (max-width:1024px){
  .ft-grid{ gap:24px 32px; }
}
@media (max-width:900px){
  .ft-grid{ grid-template-columns:repeat(2,minmax(0,1fr)); }
  .ft-subscribe{ flex-direction:column; align-items:stretch; }
  .ft-input, .ft-btn{ width:100%; }
}
@media (max-width:520px){
  .ft-grid{ grid-template-columns:1fr; }
}