:root {
  --bg-deep: #020b1a;
  --bg-mid: #061833;
  --cyan: #38bdf8;
  --cyan-bright: #7dd3fc;
  --blue: #2563eb;
  --blue-soft: #3b82f6;
  --text: #0f172a;
  --muted: #64748b;
  --line: #e2e8f0;
  --danger: #ef4444;
  --success: #16a34a;
  --card: rgba(255, 255, 255, 0.94);
  --shadow: 0 24px 60px rgba(2, 12, 36, 0.45);
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  min-height: 100%;
}

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--bg-deep);
  overflow-x: hidden;
}

.tech-bg {
  position: fixed;
  inset: 0;
  z-index: 0;
  background:
    radial-gradient(ellipse 80% 60% at 78% 48%, rgba(56, 189, 248, 0.28), transparent 55%),
    radial-gradient(ellipse 50% 40% at 18% 30%, rgba(37, 99, 235, 0.35), transparent 50%),
    linear-gradient(135deg, #020b1a 0%, #042047 45%, #03152e 100%);
}

#tech-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.bg-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(125, 211, 252, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(125, 211, 252, 0.06) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 70% 70% at 50% 50%, black 20%, transparent 75%);
  animation: grid-drift 28s linear infinite;
}

.bg-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(2px);
  pointer-events: none;
}

.orb-1 {
  width: 220px;
  height: 220px;
  left: 8%;
  top: 18%;
  background: radial-gradient(circle, rgba(125, 211, 252, 0.55), rgba(37, 99, 235, 0.05) 70%);
  animation: float-y 9s ease-in-out infinite;
}

.orb-2 {
  width: 140px;
  height: 140px;
  left: 22%;
  bottom: 16%;
  background: radial-gradient(circle, rgba(96, 165, 250, 0.4), transparent 70%);
  animation: float-y 11s ease-in-out infinite reverse;
}

.orb-3 {
  width: 90px;
  height: 90px;
  right: 12%;
  top: 14%;
  background: radial-gradient(circle, rgba(186, 230, 253, 0.5), transparent 70%);
  animation: float-y 7s ease-in-out infinite;
}

.bg-vortex {
  position: absolute;
  width: min(72vw, 760px);
  height: min(72vw, 760px);
  right: -8%;
  top: 50%;
  transform: translateY(-50%);
  border-radius: 50%;
  background:
    radial-gradient(circle at center, rgba(255, 255, 255, 0.85) 0%, rgba(125, 211, 252, 0.35) 12%, transparent 28%),
    repeating-radial-gradient(
      circle at center,
      transparent 0 14px,
      rgba(56, 189, 248, 0.12) 14px 16px
    );
  box-shadow:
    0 0 80px rgba(56, 189, 248, 0.25),
    inset 0 0 60px rgba(14, 165, 233, 0.2);
  animation: vortex-spin 48s linear infinite;
  opacity: 0.85;
}

.bg-vortex::before,
.bg-vortex::after {
  content: "";
  position: absolute;
  inset: 12%;
  border-radius: 50%;
  border: 1px solid rgba(125, 211, 252, 0.18);
}

.bg-vortex::after {
  inset: 28%;
  border-color: rgba(186, 230, 253, 0.28);
  animation: vortex-spin 22s linear infinite reverse;
}

.bg-scan {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    transparent 0%,
    rgba(56, 189, 248, 0.05) 48%,
    transparent 52%,
    transparent 100%
  );
  background-size: 100% 220%;
  animation: scan 7s ease-in-out infinite;
  pointer-events: none;
}

@keyframes float-y {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-18px);
  }
}

@keyframes vortex-spin {
  from {
    transform: translateY(-50%) rotate(0deg);
  }
  to {
    transform: translateY(-50%) rotate(360deg);
  }
}

@keyframes grid-drift {
  from {
    background-position: 0 0;
  }
  to {
    background-position: 48px 48px;
  }
}

@keyframes scan {
  0%,
  100% {
    background-position: 0 -40%;
  }
  50% {
    background-position: 0 140%;
  }
}

.auth-main {
  position: relative;
  z-index: 1;
  min-height: calc(100vh - 48px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 16px 24px;
}

.auth-card {
  width: 100%;
  max-width: 420px;
  background: var(--card);
  backdrop-filter: blur(16px);
  border-radius: 16px;
  box-shadow: var(--shadow);
  border: 1px solid rgba(255, 255, 255, 0.55);
  padding: 36px 36px 28px;
  animation: card-in 0.55s ease-out;
}

.register-card {
  max-width: 480px;
  padding: 32px 36px 24px;
}

@keyframes card-in {
  from {
    opacity: 0;
    transform: translateY(16px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.brand {
  text-align: center;
  margin-bottom: 28px;
}

.brand-compact {
  margin-bottom: 22px;
}

.brand-logo {
  width: 52px;
  height: 52px;
  margin: 0 auto 14px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  color: #fff;
  font-size: 22px;
  font-weight: 700;
  background: linear-gradient(145deg, #1d4ed8, #0ea5e9);
  box-shadow: 0 10px 24px rgba(14, 165, 233, 0.35);
  letter-spacing: 0.02em;
}

.brand h1 {
  font-size: 22px;
  font-weight: 650;
  color: #1e3a8a;
  letter-spacing: 0.04em;
}

.brand p {
  margin-top: 6px;
  font-size: 13px;
  color: var(--muted);
}

.auth-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.field-row {
  display: grid;
  grid-template-columns: 88px 1fr;
  align-items: center;
  gap: 10px;
}

.field-row .label {
  text-align: right;
  font-size: 14px;
  color: #334155;
}

.label {
  font-size: 13px;
  color: #475569;
}

.label i {
  color: var(--danger);
  font-style: normal;
  margin-right: 2px;
}

.field input,
.code-group input {
  width: 100%;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0 12px;
  font-size: 14px;
  color: var(--text);
  background: #fff;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.field input:focus,
.code-group input:focus {
  border-color: var(--blue-soft);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.code-group {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px;
  align-items: center;
}

.captcha-group .captcha-img {
  width: 220px;
  height: 72px;
  border-radius: 8px;
  border: 1px solid var(--line);
  cursor: pointer;
  object-fit: contain;
  background: #eff6ff;
  user-select: none;
  flex-shrink: 0;
}

.captcha-group .captcha-img:hover {
  border-color: #93c5fd;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.12);
}

.btn-primary,
.btn-code {
  border: none;
  cursor: pointer;
  font-family: inherit;
  font-size: 15px;
  transition: transform 0.15s, filter 0.15s, background 0.2s;
}

.btn-primary {
  margin-top: 8px;
  height: 44px;
  border-radius: 8px;
  color: #fff;
  font-weight: 600;
  background: linear-gradient(90deg, #2563eb, #0ea5e9);
  box-shadow: 0 10px 22px rgba(37, 99, 235, 0.28);
}

.btn-primary:hover {
  filter: brightness(1.05);
  transform: translateY(-1px);
}

.btn-code {
  height: 42px;
  padding: 0 14px;
  border-radius: 8px;
  white-space: nowrap;
  color: #1d4ed8;
  background: #eff6ff;
  border: 1px solid #bfdbfe;
}

.btn-code:hover:not(:disabled) {
  background: #dbeafe;
}

.btn-code:disabled {
  opacity: 0.65;
  cursor: not-allowed;
}

.auth-link {
  display: block;
  margin-top: 18px;
  text-align: center;
  color: var(--blue);
  font-size: 14px;
  text-decoration: none;
}

.auth-link:hover {
  text-decoration: underline;
}

.alert {
  margin-bottom: 14px;
  padding: 10px 12px;
  border-radius: 8px;
  font-size: 13px;
}

.alert-error {
  background: #fef2f2;
  color: #b91c1c;
  border: 1px solid #fecaca;
}

.alert-success {
  background: #f0fdf4;
  color: #166534;
  border: 1px solid #bbf7d0;
}

.alert-success a {
  color: var(--blue);
  margin-left: 6px;
}

.auth-footer {
  position: relative;
  z-index: 1;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(226, 232, 240, 0.72);
  font-size: 12px;
  letter-spacing: 0.02em;
}

@media (max-width: 560px) {
  .auth-card {
    padding: 28px 20px 22px;
  }

  .field-row {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .field-row .label {
    text-align: left;
  }

  .bg-vortex {
    right: -35%;
    opacity: 0.55;
  }
}