:root {
  --bg: #ffffff;
  --surface: #f5f5f5;
  --card: rgba(255, 255, 255, 0.82);
  --text: #050505;
  --text-muted: rgba(0, 0, 0, 0.45);
  --text-placeholder: rgba(0, 0, 0, 0.3);
  --border: rgba(0, 0, 0, 0.1);
  --border-hover: rgba(0, 0, 0, 0.22);
  --accent: #050505;
  --accent-contrast: #ffffff;
  --shadow: rgba(0, 0, 0, 0.08);
  --ease-out: cubic-bezier(0.23, 1, 0.32, 1);
  --ease-in-out: cubic-bezier(0.77, 0, 0.175, 1);
  --duration-fast: 160ms;
  --duration-base: 240ms;
}

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

html,
body {
  height: 100%;
}

body {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -webkit-text-size-adjust: 100%;
  overflow-x: hidden;
}

/* ========== 星球与星轨背景 ========== */
.auth-planet {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  display: grid;
  place-items: center;
  overflow: hidden;
  opacity: 0;
  animation: planetFadeIn 900ms var(--ease-out) 200ms forwards;
}

.auth-planet svg {
  width: min(72vw, 520px);
  height: min(72vw, 520px);
  transform: translateY(-6vh);
}

.auth-planet-body {
  transform-origin: 180px 180px;
  color: rgba(0, 0, 0, 0.18);
}

.auth-planet-orbit {
  transform-origin: 180px 180px;
  color: rgba(0, 0, 0, 0.12);
  animation: authOrbit 28s linear infinite;
}

@keyframes authOrbit {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes planetFadeIn {
  from { opacity: 0; transform: scale(0.96); }
  to { opacity: 1; transform: scale(1); }
}

/* ========== 页面容器 ========== */
.auth-page {
  width: 100%;
  max-width: 440px;
  position: relative;
  z-index: 1;
  opacity: 0;
  transform: translateY(16px);
  animation: cardEnter 700ms var(--ease-out) 320ms forwards;
}

@keyframes cardEnter {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.auth-card {
  width: 100%;
  padding: 44px 40px;
  background: var(--card);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  border-radius: 28px;
  box-shadow: 0 24px 80px var(--shadow);
}

.auth-home-link {
  text-align: center;
  margin-top: 22px;
}

.auth-home-link a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  color: var(--text-muted);
  letter-spacing: 0.04em;
  transition: color 200ms var(--ease-out);
}

@media (hover: hover) and (pointer: fine) {
  .auth-home-link a:hover {
    color: var(--text);
  }
}

/* ========== 品牌区 ========== */
.auth-brand {
  text-align: center;
  margin-bottom: 32px;
}

.auth-brand-title {
  font-size: clamp(1.6rem, 5vw, 2rem);
  font-weight: 700;
  letter-spacing: 0.04em;
  margin-bottom: 6px;
}

.auth-brand-subtitle {
  font-size: 0.85rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
}

/* ========== 登录 / 注册 切换 ========== */
.auth-tabs {
  display: flex;
  margin-bottom: 28px;
  padding: 4px;
  background: var(--surface);
  border-radius: 999px;
  position: relative;
}

.auth-tab {
  flex: 1;
  padding: 10px 12px;
  border: none;
  background: transparent;
  color: var(--text);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border-radius: 999px;
  position: relative;
  z-index: 1;
  transition: color 250ms var(--ease-out);
}

.auth-tab.active {
  color: var(--accent-contrast);
}

.auth-tab-indicator {
  position: absolute;
  top: 4px;
  bottom: 4px;
  left: 4px;
  width: calc(50% - 4px);
  background: var(--accent);
  border-radius: 999px;
  transition: transform 250ms var(--ease-out);
  z-index: 0;
}

.auth-tabs[data-active="register"] .auth-tab-indicator {
  transform: translateX(100%);
}

/* ========== 面板 ========== */
.auth-panels {
  position: relative;
  overflow: hidden;
}

.auth-panel {
  display: none;
  opacity: 0;
  transform: translateX(18px);
  transition: opacity 250ms var(--ease-out), transform 250ms var(--ease-out);
}

.auth-panel.active {
  display: block;
  opacity: 1;
  transform: translateX(0);
}

/* ========== 输入框 ========== */
.auth-input-group {
  margin-bottom: 18px;
}

.auth-input-group label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 6px;
  letter-spacing: 0.02em;
}

.auth-input-wrap {
  position: relative;
  display: flex;
  align-items: center;
}

.auth-input-icon {
  position: absolute;
  left: 16px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  transition: color var(--duration-fast) var(--ease-out);
}

.auth-input-wrap input[type="text"],
.auth-input-wrap input[type="password"] {
  width: 100%;
  padding: 13px 14px 13px 48px;
  font-size: 0.95rem;
  border-radius: 12px;
  background: var(--bg);
  border: 1.5px solid var(--border);
  color: var(--text);
  transition: border-color var(--duration-fast) var(--ease-out),
    box-shadow var(--duration-fast) var(--ease-out),
    background-color var(--duration-fast) var(--ease-out);
}

.auth-input-wrap input[type="text"]:focus,
.auth-input-wrap input[type="password"]:focus {
  background: var(--bg);
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(0, 0, 0, 0.06);
  outline: none;
}

.auth-input-wrap input[type="text"]:focus ~ .auth-input-icon,
.auth-input-wrap input[type="password"]:focus ~ .auth-input-icon,
.auth-input-wrap:focus-within .auth-input-icon {
  color: var(--accent);
}

.auth-input-wrap input::placeholder {
  color: var(--text-placeholder);
}

/* ========== 提交按钮 ========== */
.auth-submit {
  width: 100%;
  margin-top: 8px;
  padding: 14px;
  border: none;
  border-radius: 999px;
  background: var(--accent);
  color: var(--accent-contrast);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform var(--duration-fast) var(--ease-out),
    box-shadow var(--duration-fast) var(--ease-out),
    opacity var(--duration-fast) var(--ease-out);
}

.auth-submit:active {
  transform: scale(0.98);
}

.auth-submit:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

@media (hover: hover) and (pointer: fine) {
  .auth-submit:hover {
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.14);
  }
}

/* ========== 轻提示 ========== */
.toast {
  position: fixed;
  top: 20px;
  left: 50%;
  transform: translateX(-50%) translateY(-10px);
  padding: 12px 22px;
  border-radius: 999px;
  background: var(--accent);
  color: var(--accent-contrast);
  font-size: 0.9rem;
  font-weight: 500;
  opacity: 0;
  pointer-events: none;
  transition: opacity 250ms var(--ease-out), transform 250ms var(--ease-out);
  z-index: 200;
}

.toast.visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.toast.hidden {
  display: none;
}

/* ========== 验证码弹窗 ========== */
.modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 150;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(0, 0, 0, 0.35);
  opacity: 0;
  pointer-events: none;
  transition: opacity 250ms var(--ease-out);
}

.modal-overlay.visible {
  opacity: 1;
  pointer-events: all;
}

.modal-overlay.hidden {
  display: none;
}

.modal {
  width: 100%;
  max-width: 380px;
  background: var(--bg);
  border-radius: 20px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.2);
  overflow: hidden;
  transform: scale(0.96);
  opacity: 0;
  transition: transform 250ms var(--ease-out), opacity 250ms var(--ease-out);
}

.modal-overlay.visible .modal {
  transform: scale(1);
  opacity: 1;
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 20px;
  border-bottom: 1px solid var(--border);
}

.modal-header h3 {
  font-size: 1rem;
  font-weight: 600;
}

.modal-close {
  width: 32px;
  height: 32px;
  border: none;
  border-radius: 50%;
  background: transparent;
  color: var(--text-muted);
  font-size: 22px;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color var(--duration-fast) var(--ease-out), background-color var(--duration-fast) var(--ease-out);
}

.modal-close:hover {
  background: var(--surface);
  color: var(--text);
}

.modal-body {
  padding: 20px;
}

.captcha-tip {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 12px;
  text-align: center;
}

.captcha-box {
  position: relative;
  width: 100%;
  max-width: 320px;
  aspect-ratio: 280 / 160;
  margin: 0 auto 16px;
  border-radius: 12px;
  overflow: hidden;
  background: var(--surface);
  box-shadow: inset 0 0 0 1px var(--border);
}

.captcha-box canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.captcha-refresh {
  position: absolute;
  top: 8px;
  right: 8px;
  width: 32px;
  height: 32px;
  border: none;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.9);
  color: var(--text-muted);
  font-size: 18px;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  transition: transform 160ms var(--ease-out), color 160ms var(--ease-out);
}

.captcha-refresh:active {
  transform: scale(0.92);
}

.captcha-track {
  position: relative;
  width: 100%;
  max-width: 320px;
  height: 44px;
  margin: 0 auto;
  border-radius: 12px;
  background: var(--surface);
  border: 1.5px solid var(--border);
  overflow: hidden;
  touch-action: none;
}

.captcha-track-mask {
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 0;
  background: rgba(0, 0, 0, 0.08);
  border-right: 1.5px solid var(--accent);
  transition: width 80ms linear;
}

.captcha-track-text {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  color: var(--text-muted);
  pointer-events: none;
}

.captcha-btn {
  position: absolute;
  left: 0;
  top: 0;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--bg);
  border: 1.5px solid var(--accent);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  transform: translateX(0);
  transition: background-color 160ms var(--ease-out),
    color 160ms var(--ease-out),
    transform 80ms linear;
  touch-action: none;
}

.captcha-btn:active {
  transform: translateX(var(--captcha-x, 0)) scale(0.96);
}

.captcha-btn.success {
  background: #10b981;
  border-color: #10b981;
  color: #ffffff;
}

.captcha-btn.fail {
  background: #ef4444;
  border-color: #ef4444;
  color: #ffffff;
}

.captcha-status {
  margin-top: 12px;
  min-height: 22px;
  text-align: center;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-muted);
}

.captcha-status.success {
  color: #10b981;
}

.captcha-status.fail {
  color: #ef4444;
}

/* ========== 登录成功 → 星轨导航过渡（空间跃迁） ========== */
.page-transition {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: grid;
  place-items: center;
  background: #000000;
  opacity: 0;
  pointer-events: none;
  transition: opacity 350ms var(--ease-out);
  overflow: hidden;
}

.page-transition.active {
  opacity: 1;
  pointer-events: all;
}

.page-transition::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 50% 50%, rgba(6, 182, 212, 0.25) 0%, rgba(59, 130, 246, 0.12) 18%, rgba(5, 8, 30, 0.96) 45%, #000000 70%);
  clip-path: circle(0% at 50% 50%);
  z-index: 1;
}

.page-transition.expand::before {
  animation: portalExpand 1400ms var(--ease-in-out) forwards;
}

/* 跃迁星尘 */
.warp-stars {
  position: absolute;
  inset: -50%;
  z-index: 1;
  background:
    radial-gradient(2px 2px at 20% 30%, rgba(255,255,255,0.9), transparent),
    radial-gradient(1.5px 1.5px at 70% 20%, rgba(255,255,255,0.7), transparent),
    radial-gradient(1px 1px at 40% 80%, rgba(255,255,255,0.6), transparent),
    radial-gradient(2px 2px at 80% 70%, rgba(6,182,212,0.7), transparent),
    radial-gradient(1.5px 1.5px at 10% 60%, rgba(139,92,246,0.6), transparent),
    radial-gradient(1px 1px at 60% 40%, rgba(255,255,255,0.5), transparent),
    radial-gradient(2px 2px at 30% 50%, rgba(6,182,212,0.5), transparent),
    radial-gradient(1.5px 1.5px at 90% 40%, rgba(255,255,255,0.6), transparent);
  background-size: 260px 260px;
  opacity: 0;
  transform: scale(0.8);
  transition: opacity 400ms var(--ease-out), transform 400ms var(--ease-out);
}

.page-transition.go .warp-stars {
  opacity: 1;
  animation: warpSpeed 1400ms var(--ease-in-out) forwards;
}

/* 中央能量核 */
.warp-core {
  position: absolute;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255,255,255,0.95) 0%, rgba(6,182,212,0.6) 35%, rgba(59,130,246,0.2) 60%, transparent 70%);
  box-shadow: 0 0 80px rgba(6,182,212,0.5), 0 0 160px rgba(59,130,246,0.3);
  z-index: 2;
  opacity: 0;
}

.page-transition.go .warp-core {
  animation: coreExpand 1400ms var(--ease-in-out) forwards;
}

/* 旋转光环 */
.warp-ring {
  position: absolute;
  width: 180px;
  height: 180px;
  border-radius: 50%;
  border: 1px solid rgba(6, 182, 212, 0.35);
  z-index: 2;
  opacity: 0;
}

.page-transition.go .warp-ring {
  animation: ringExpand 1400ms var(--ease-in-out) forwards;
}

.transition-inner {
  position: relative;
  z-index: 3;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}

.transition-logo {
  font-size: clamp(1.6rem, 5vw, 2.4rem);
  font-weight: 700;
  letter-spacing: 0.22em;
  color: rgba(255, 255, 255, 0.95);
  opacity: 0;
  transform: translateY(10px);
  text-shadow: 0 0 24px rgba(6, 182, 212, 0.45);
}

.transition-line {
  width: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.8), transparent);
}

.page-transition.go .transition-logo {
  animation: fadeInUp 700ms var(--ease-out) 120ms forwards;
}

.page-transition.go .transition-line {
  animation: lineExpand 800ms var(--ease-in-out) forwards;
}

@keyframes lineExpand {
  to { width: 140px; }
}

@keyframes portalExpand {
  to { clip-path: circle(150% at 50% 50%); }
}

@keyframes warpSpeed {
  0% { transform: scale(0.8); opacity: 0.4; }
  40% { opacity: 1; }
  100% { transform: scale(2.2); opacity: 0; }
}

@keyframes coreExpand {
  0% { width: 0; height: 0; opacity: 0; }
  30% { opacity: 1; }
  100% { width: 220vmax; height: 220vmax; opacity: 1; }
}

@keyframes ringExpand {
  0% { transform: scale(0.6); opacity: 0; }
  20% { opacity: 1; }
  100% { transform: scale(8); opacity: 0; }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ========== 移动端适配 ========== */
@media (max-width: 560px) {
  body {
    padding: 16px;
    align-items: flex-start;
    padding-top: 10vh;
  }

  .auth-card {
    padding: 32px 24px;
    border-radius: 22px;
  }

  .auth-brand {
    margin-bottom: 24px;
  }

  .auth-tabs {
    margin-bottom: 22px;
  }

  .captcha-modal {
    max-width: 100%;
    margin: 0 12px;
  }

  .captcha-box,
  .captcha-track {
    max-width: 100%;
  }
}

/* ========== 减少动画 ========== */
@media (prefers-reduced-motion: reduce) {
  .auth-page,
  .auth-planet {
    animation: none;
    opacity: 1;
    transform: none;
  }

  .auth-planet-orbit {
    animation: none;
  }

  .auth-tab-indicator,
  .auth-panel,
  .modal,
  .modal-overlay,
  .toast {
    transition: none;
  }

  .page-transition,
  .page-transition::before,
  .transition-logo,
  .transition-line {
    animation: none !important;
    transition: none;
  }
}