.auth-shell {
  width: min(1020px, 94vw);
  margin: 40px auto;
  display: grid;
  grid-template-columns: minmax(320px, 1.05fr) minmax(320px, 1fr);
  gap: 20px;
  align-items: stretch;
  position: relative;
  z-index: 1;
}

/* 浮动几何背景动效 - 减少数量，简化动画 */
.auth-bg-shapes {
  position: fixed;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

.shape {
  position: absolute;
  border-radius: 50%;
  opacity: 0;
  filter: blur(20px);
  animation: floatIn 0.8s ease-out forwards, floatMove linear infinite;
}

.shape-circle {
  border-radius: 50%;
}

.shape-square {
  border-radius: 12px;
  transform: rotate(45deg);
}

.shape-1 {
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.25), rgba(79, 70, 229, 0.12));
  top: 12%;
  left: 6%;
  animation-delay: 0s, 0.8s;
  animation-duration: 0.8s, 22s;
}

.shape-2 {
  width: 55px;
  height: 55px;
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.2), rgba(99, 102, 241, 0.1));
  top: 22%;
  right: 10%;
  animation-delay: 0.2s, 1s;
  animation-duration: 0.8s, 26s;
}

.shape-3 {
  width: 100px;
  height: 100px;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.18), rgba(99, 102, 241, 0.08));
  bottom: 18%;
  left: 4%;
  animation-delay: 0.4s, 1.2s;
  animation-duration: 0.8s, 28s;
}

.shape-4 {
  width: 45px;
  height: 45px;
  background: linear-gradient(135deg, rgba(236, 72, 153, 0.2), rgba(139, 92, 246, 0.1));
  top: 55%;
  right: 6%;
  animation-delay: 0.6s, 1.4s;
  animation-duration: 0.8s, 24s;
}

.shape-5 {
  width: 70px;
  height: 70px;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.15), rgba(59, 130, 246, 0.08));
  bottom: 25%;
  right: 18%;
  animation-delay: 0.3s, 1.6s;
  animation-duration: 0.8s, 30s;
}

.shape-6 {
  width: 35px;
  height: 35px;
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.22), rgba(99, 102, 241, 0.12));
  top: 38%;
  left: 12%;
  animation-delay: 0.5s, 1.8s;
  animation-duration: 0.8s, 23s;
}

.shape-7 {
  width: 90px;
  height: 90px;
  background: linear-gradient(135deg, rgba(79, 70, 229, 0.14), rgba(139, 92, 246, 0.07));
  top: 8%;
  right: 22%;
  animation-delay: 0.7s, 2s;
  animation-duration: 0.8s, 32s;
}

.shape-8 {
  width: 50px;
  height: 50px;
  background: linear-gradient(135deg, rgba(236, 72, 153, 0.15), rgba(139, 92, 246, 0.08));
  bottom: 12%;
  left: 22%;
  animation-delay: 0.9s, 2.2s;
  animation-duration: 0.8s, 27s;
}

@keyframes floatIn {
  from {
    opacity: 0;
    transform: scale(0.5) translateY(20px);
  }
  to {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
}

@keyframes floatMove {
  0% {
    transform: translate(0, 0) rotate(0deg);
  }
  33% {
    transform: translate(12px, -20px) rotate(4deg);
  }
  66% {
    transform: translate(-8px, -12px) rotate(-2deg);
  }
  100% {
    transform: translate(0, 0) rotate(0deg);
  }
}

.shape-square {
  animation-name: floatIn, floatMoveSquare;
}

@keyframes floatMoveSquare {
  0% {
    transform: rotate(45deg) translate(0, 0);
  }
  33% {
    transform: rotate(48deg) translate(10px, -15px);
  }
  66% {
    transform: rotate(42deg) translate(-6px, -10px);
  }
  100% {
    transform: rotate(45deg) translate(0, 0);
  }
}

/* Auth side panel - glass effect */
.auth-side {
  padding: 28px;
  border-radius: var(--radius-card);
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow), var(--glass-inset-light);
  display: flex;
  flex-direction: column;
}

.auth-side h1 {
  color: var(--text);
  font-size: clamp(28px, 3vw, 36px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.auth-side > p {
  margin-top: 10px;
  font-size: 15px;
  color: var(--text-muted);
}

.auth-side ul {
  margin: 20px 0 0;
  padding-left: 20px;
  display: grid;
  gap: 10px;
  color: var(--text);
  font-size: 14px;
  line-height: 1.5;
}

.auth-side ul li::marker {
  color: var(--primary);
}

.auth-side-actions {
  margin-top: auto;
  padding-top: 24px;
}

/* Auth main card - stronger glass */
.auth-main {
  padding: 28px;
  border-radius: var(--radius-card);
  background: var(--glass-bg-strong);
  backdrop-filter: var(--glass-blur-strong);
  -webkit-backdrop-filter: var(--glass-blur-strong);
  border: 1px solid var(--glass-border-strong);
  box-shadow: var(--glass-shadow), var(--glass-inset-light);
  display: grid;
  align-content: start;
  gap: 14px;
}

.auth-main h2 {
  color: var(--text);
  font-size: 22px;
  font-weight: 600;
}

.hint {
  margin: 0;
  font-size: 13px;
  color: var(--text-muted);
}

.auth-form {
  display: grid;
  gap: 10px;
}

.auth-form label {
  font-size: 13px;
  color: var(--text);
  font-weight: 500;
}

.auth-form input {
  min-height: 42px;
}

.auth-form .btn[type="submit"] {
  margin-top: 6px;
  min-height: 44px;
  font-size: 15px;
}

.captcha-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 10px;
}

.captcha-question {
  min-height: 24px;
  display: inline-flex;
  align-items: center;
  font-size: 13px;
  color: var(--text);
  border: 1px dashed var(--glass-border);
  border-radius: var(--radius-sm);
  padding: 8px 12px;
  background: var(--bg-muted);
}

.auth-switch {
  font-size: 13px;
  color: var(--text-muted);
}

.auth-switch a {
  color: var(--primary);
  font-weight: 600;
  text-decoration: none;
}

.auth-switch a:hover {
  text-decoration: underline;
}

@media (max-width: 900px) {
  .auth-shell {
    margin-top: 20px;
    grid-template-columns: 1fr;
  }

  .auth-side,
  .auth-main {
    padding: 20px;
  }

  .captcha-row {
    grid-template-columns: 1fr;
  }

  .captcha-row .btn,
  .auth-side-actions .btn {
    width: 100%;
  }

  .shape {
    transform: scale(0.7);
  }
}

@media (prefers-reduced-motion: reduce) {
  .shape {
    animation: none !important;
    opacity: 0.5;
  }
}