:root {
  --bg: #f5f5f7;
  --card: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --border: #d2d2d7;
  --primary: #0071e3;
  --danger: #d70015;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Helvetica Neue", sans-serif;
  background: var(--bg);
  color: var(--text);
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
}
.wrap { padding: 24px; width: 100%; display: flex; justify-content: center; }
.card {
  background: var(--card);
  border-radius: 16px;
  padding: 40px 36px;
  width: 100%;
  max-width: 380px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
}
.logo {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 2px;
  color: var(--primary);
  margin-bottom: 18px;
}
h1 { font-size: 20px; margin: 0 0 8px; }
.hint { font-size: 13px; color: var(--muted); line-height: 1.6; margin: 0 0 22px; }
input {
  width: 100%;
  height: 42px;
  padding: 0 14px;
  font-size: 15px;
  border: 1px solid var(--border);
  border-radius: 10px;
  outline: none;
  background: #fff;
  color: var(--text);
}
input:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(0, 113, 227, 0.15); }
button {
  width: 100%;
  height: 42px;
  margin-top: 14px;
  font-size: 15px;
  font-weight: 600;
  color: #fff;
  background: var(--primary);
  border: none;
  border-radius: 10px;
  cursor: pointer;
}
button:hover { background: #0077ed; }
button:disabled { opacity: 0.5; cursor: default; }
.msg { min-height: 20px; margin-top: 12px; font-size: 13px; color: var(--danger); }