/* 基础重置与变量 */
* { margin: 0; padding: 0; box-sizing: border-box; }
html, body { height: 100%; }
body { font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Helvetica Neue", Arial, sans-serif; color: #1d2129; }

/* 背景与居中布局 */
body {
  background: radial-gradient(1200px 600px at 80% -20%, #e6f0ff 0%, rgba(230,240,255,0) 60%),
              radial-gradient(1000px 500px at -10% 110%, #f3f7ff 0%, rgba(243,247,255,0) 60%),
              linear-gradient(135deg, #f7fbff, #f9fbff);
  display: grid;
  place-items: center;
}

/* 容器卡片 */
.auth-page { width: 92%; max-width: 420px; }
.card {
  background: #ffffff;
  border-radius: 16px;
  box-shadow: 0 12px 36px rgba(0, 42, 128, 0.10);
  overflow: hidden;
}

/* 品牌头 */
.brand { padding: 22px 20px; border-bottom: 1px solid #f0f2f5; background: linear-gradient(90deg, #fbfdff, #ffffff); }
.brand-logo { font-size: 18px; font-weight: 700; color: #165DFF; letter-spacing: 1px; }
.brand-name { font-size: 14px; color: #4e5969; margin-top: 2px; }

/* 标签切换 */
.tabs { display: grid; grid-template-columns: 1fr 1fr; gap: 0; padding: 10px; }
.tab {
  appearance: none; border: 0; background: #f5f7fa; color: #4e5969;
  padding: 10px 12px; border-radius: 10px; cursor: pointer; font-size: 14px; transition: all .2s;
}
.tab.active { background: #e8f3ff; color: #165DFF; font-weight: 600; box-shadow: inset 0 0 0 1px #bcd6ff; }
.tab:focus-visible { outline: 2px solid #165DFF; outline-offset: 2px; }

/* 表单 */
.tab-content { padding: 4px 16px 16px 16px; }
.form { display: block; }
.form-item { margin: 12px 0; position: relative; }
.form-item input {
  width: 100%; padding: 12px 14px; border: 1px solid #e5e6eb; border-radius: 10px; background: #ffffff;
  font-size: 14px; color: #1d2129; transition: border-color .2s, box-shadow .2s;
}
.form-item input::placeholder { color: #86909c; }
.form-item input:focus { border-color: #165DFF; box-shadow: 0 0 0 3px rgba(22,93,255,.12); outline: none; }

/* 输入框 + 行为按钮组合 */
.with-action { display: grid; grid-template-columns: 1fr auto; gap: 10px; align-items: center; }
.with-action input { margin: 0; }

/* 按钮 */
.btn { appearance: none; border: 0; border-radius: 10px; cursor: pointer; line-height: 1; }
.btn.primary {
  width: 100%; padding: 12px 14px; background: #165DFF; color: #fff; font-size: 15px; font-weight: 600;
  box-shadow: 0 6px 16px rgba(22,93,255,.25); transition: transform .1s ease, background-color .2s ease;
}
.btn.primary:hover { background: #0e42d2; }
.btn.primary:active { transform: translateY(1px); }

.btn.ghost {
  padding: 10px 12px; background: #f2f3f5; color: #165DFF; font-size: 14px; font-weight: 600;
  box-shadow: inset 0 0 0 1px #d0d3da; white-space: nowrap;
}
.btn[disabled] { opacity: .6; cursor: not-allowed; box-shadow: none; }

/* 下方链接 */
.links { display: flex; justify-content: center; align-items: center; gap: 8px; padding: 14px 16px 18px; border-top: 1px solid #f0f2f5; }
.link { color: #165DFF; font-size: 13px; text-decoration: none; }
.link:hover { text-decoration: underline; }
.divider { color: #c9cdd4; }

/* 通用工具类 */
.hidden { display: none !important; }

/* 小屏优化 */
@media (max-width: 340px) {
  .btn.primary { font-size: 14px; }
  .tab { font-size: 13px; padding: 9px 10px; }
}