/* =========================================================================
   登录 / 认证页
   左右分栏：品牌面板 + 表单卡。窄屏隐藏品牌面板并居中表单。
   ========================================================================= */

.auth-body {
  margin: 0;
  min-height: 100vh;
  background: var(--c-bg);
}

.auth-shell {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  min-height: 100vh;
}

/* ── 品牌面板 ─────────────────────────────────────────────────────────── */
.auth-brand {
  position: relative;
  display: flex;
  align-items: center;
  padding: var(--s-10) clamp(40px, 6vw, 96px);
  overflow: hidden;
  background:
    radial-gradient(120% 100% at 0% 0%, #6366f1 0%, #4f46e5 38%, #4338ca 68%, #312e81 100%);
  color: #fff;
  isolation: isolate;
}

/* 网格纹理 */
.auth-brand::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(to right, rgba(255,255,255,0.055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255,255,255,0.055) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(90% 70% at 30% 35%, #000 20%, transparent 78%);
  -webkit-mask-image: radial-gradient(90% 70% at 30% 35%, #000 20%, transparent 78%);
}

/* 柔和光斑 */
.auth-brand-glow {
  position: absolute;
  z-index: -1;
  width: 620px; height: 620px;
  right: -220px; bottom: -260px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(167,139,250,0.55) 0%, rgba(139,92,246,0) 68%);
  filter: blur(6px);
  pointer-events: none;
}

.auth-brand-inner { position: relative; max-width: 420px; }

.auth-logo {
  display: grid;
  place-items: center;
  width: 56px; height: 56px;
  border-radius: var(--r-lg);
  background: rgba(255, 255, 255, 0.16);
  border: 1px solid rgba(255, 255, 255, 0.24);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  font-size: var(--f-lg);
  font-weight: var(--fw-extrabold);
  letter-spacing: -0.02em;
  box-shadow: 0 8px 24px rgba(15, 23, 42, 0.28);
}

.auth-brand-title {
  margin-top: var(--s-7);
  font-size: clamp(28px, 3.2vw, var(--f-4xl));
  font-weight: var(--fw-extrabold);
  letter-spacing: -0.028em;
  line-height: 1.15;
  color: #fff;
}

.auth-brand-sub {
  margin-top: var(--s-3);
  font-size: var(--f-md);
  color: rgba(255, 255, 255, 0.72);
}

.auth-features {
  margin: var(--s-9) 0 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--s-3);
}

.auth-features li {
  display: flex;
  align-items: center;
  gap: var(--s-3);
  font-size: var(--f-sm);
  color: rgba(255, 255, 255, 0.86);
}

.auth-features li svg { flex-shrink: 0; opacity: 0.9; }

/* ── 表单区 ───────────────────────────────────────────────────────────── */
.auth-main {
  display: grid;
  place-items: center;
  padding: var(--s-8) var(--s-6);
}

.auth-card {
  width: 100%;
  max-width: 384px;
}

.auth-head { margin-bottom: var(--s-7); }

.auth-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--s-1);
  height: 24px;
  padding: 0 var(--s-2);
  border-radius: var(--r-sm);
  background: var(--c-primary-50);
  color: var(--c-primary-700);
  font-size: var(--f-xs);
  font-weight: var(--fw-semibold);
}

.auth-title {
  margin-top: var(--s-4);
  font-size: var(--f-2xl);
  font-weight: var(--fw-bold);
  letter-spacing: -0.022em;
}

.auth-sub {
  margin-top: var(--s-2);
  font-size: var(--f-sm);
  color: var(--c-text-soft);
}

.auth-form {
  display: flex;
  flex-direction: column;
  gap: var(--s-4);
}

.auth-form .btn-block { margin-top: var(--s-2); height: 46px; }

.auth-error {
  display: flex;
  align-items: flex-start;
  gap: var(--s-2);
  padding: var(--s-3) var(--s-3);
  border-radius: var(--r-md);
  background: var(--c-danger-bg);
  border: 1px solid #fecdd3;
  color: var(--c-danger-text);
  font-size: var(--f-sm);
  line-height: var(--lh-snug);
  animation: auth-shake 360ms cubic-bezier(0.36, 0.07, 0.19, 0.97);
}
[data-theme="dark"] .auth-error { border-color: #881337; }

@keyframes auth-shake {
  10%, 90% { transform: translateX(-1px); }
  20%, 80% { transform: translateX(2px); }
  30%, 50%, 70% { transform: translateX(-3px); }
  40%, 60% { transform: translateX(3px); }
}

.auth-foot {
  margin-top: var(--s-8);
  font-size: var(--f-xs);
  color: var(--c-text-faint);
  text-align: center;
}

/* ── 响应式 ───────────────────────────────────────────────────────────── */
@media (max-width: 900px) {
  .auth-shell { grid-template-columns: 1fr; }
  .auth-brand { display: none; }
  .auth-main { padding: var(--s-7) var(--s-4); align-items: center; }
  .auth-card { max-width: 400px; }
}

@media (max-width: 420px) {
  .auth-title { font-size: var(--f-xl); }
}