:root { --bg:#0b0d12; --panel:#141821; --text:#e8eaf0; --muted:#8b93a7; --accent:#6ea8fe; --border:#242a36; }
* { box-sizing: border-box; }
body {
  margin: 0; min-height: 100vh; display: grid; place-items: center;
  background: radial-gradient(circle at top, #182033 0, #0b0d12 55%);
  color: var(--text); font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", sans-serif;
}
.login-card {
  width: min(420px, calc(100vw - 32px)); background: rgba(20,24,33,.92);
  border: 1px solid var(--border); border-radius: 18px; padding: 28px;
  box-shadow: 0 24px 80px rgba(0,0,0,.45);
}
.brand { font-size: 26px; font-weight: 700; letter-spacing: -.02em; }
.sub { margin: 6px 0 22px; color: var(--muted); font-size: 13px; }
label { display: block; font-size: 13px; color: var(--muted); margin-bottom: 14px; }
input {
  width: 100%; margin-top: 6px; padding: 12px 12px; border-radius: 10px;
  border: 1px solid #2a3140; background: #0f131b; color: var(--text);
  font: inherit; font-size: 15px; outline: none;
}
input:focus { border-color: var(--accent); }
.captcha-row { display: flex; gap: 10px; align-items: center; margin-top: 6px; }
.captcha-row input { margin-top: 0; flex: 1; }
#captcha { width: 120px; height: 40px; border-radius: 8px; background: #12151c; cursor: pointer; }
button {
  width: 100%; margin-top: 8px; padding: 12px; border: 0; border-radius: 10px;
  background: var(--accent); color: #07111f; font: inherit; font-weight: 700; cursor: pointer;
}
button:hover { filter: brightness(1.08); }
.error { background: #3a1b22; border: 1px solid #6b2d3a; color: #ffb4c0; padding: 10px 12px; border-radius: 10px; font-size: 13px; margin-bottom: 14px; }
.hint { color: var(--muted); font-size: 11px; line-height: 1.6; margin: 18px 0 0; }
code { color: #b9c7e6; }