:root {
  --primary-900: #0A2351;
  --primary-800: #123368;
  --primary-600: #1A4B8C;
  --primary-500: #2A6BA7;
  --primary-400: #3B7CB1;
  --primary-200: #8DB9E3;
  --primary-100: #E3F2FD;
  --accent-500: #FF7A00;
  --success-500: #00B74A;
  --error-500: #D32F2F;
  --warning-500: #FFC107;
  --gray-900: #212121;
  --gray-800: #424242;
  --gray-600: #757575;
  --gray-400: #BDBDBD;
  --gray-300: #E0E0E0;
  --gray-200: #EEEEEE;
  --surface-white: #FFFFFF;
  --overlay-black: rgba(0, 0, 0, 0.6);

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.2);
  --shadow-input: 0 2px 4px rgba(58, 124, 177, 0.1);

  --transition-fast: all 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-medium: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  background: var(--primary-100);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'PingFang SC', 'Microsoft YaHei', 'SF Pro Text', system-ui, sans-serif;
  line-height: 1.6;
  color: var(--gray-900);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.login-container {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  width: 1000px;
  height: 640px;
  background: var(--surface-white);
  border-radius: 24px;
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  position: relative;
  transform: translateY(0);
  transition: var(--transition-medium);
}

.login-container:hover {
  transform: translateY(-4px);
}

.brand-side {
  padding: 48px;
  background: linear-gradient(135deg, var(--primary-900) 0%, var(--primary-800) 100%);
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  overflow: hidden;
}

.brand-side::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 70% 30%,
    rgba(255, 255, 255, 0.04) 0%,
    rgba(255, 255, 255, 0.02) 15%,
    transparent 40%);
  transform: rotate(45deg);
  pointer-events: none;
}

.logo-container {
  display: flex;
  align-items: center;
  margin-bottom: 40px;
  position: relative;
  transition: var(--transition-fast);
}

.logo-container:hover {
  transform: translateX(4px);
}

.logo-text {
  font-size: 28px;
  font-weight: 700;
  color: var(--surface-white);
  letter-spacing: 0.5px;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.brand-tagline {
  font-size: 32px;
  line-height: 1.3;
  color: var(--surface-white);
  margin-bottom: 24px;
  position: relative;
}

.brand-tagline::after {
  content: "";
  display: block;
  width: 60px;
  height: 4px;
  background: var(--primary-200);
  margin-top: 16px;
  border-radius: 2px;
}

.brand-description {
  color: rgba(255,255,255,0.85);
  line-height: 1.6;
  margin-bottom: 32px;
  font-size: 15px;
}

.feature-list {
  list-style: none;
}

.feature-item {
  display: flex;
  align-items: center;
  margin-bottom: 16px;
  color: rgba(255,255,255,0.9);
  transition: var(--transition-fast);
}

.feature-item:hover {
  transform: translateX(8px);
}

.feature-icon {
  width: 36px;
  height: 36px;
  background: rgba(255,255,255,0.1);
  border-radius: 10px;
  margin-right: 16px;
  display: grid;
  place-items: center;
  color: var(--surface-white);
  transition: var(--transition-fast);
}

.feature-item:hover .feature-icon {
  background: rgba(255,255,255,0.15);
  transform: scale(1.1);
}


.login-side {
  padding: 60px 48px;
  position: relative;
}

.login-header {
  margin-bottom: 48px;
}

.login-title {
  font-size: 28px;
  color: var(--primary-900);
  margin-bottom: 12px;
  font-weight: 700;
  position: relative;
}

.login-title::after {
  content: "";
  display: block;
  width: 40px;
  height: 3px;
  background: var(--primary-600);
  margin-top: 8px;
  border-radius: 2px;
}

.login-subtitle {
  color: var(--gray-600);
  font-size: 15px;
  line-height: 1.5;
}

.login-form {
  margin-bottom: 24px;
}

.form-group {
  margin-bottom: 24px;
  position: relative;
}

.form-input-wrapper {
  position: relative;
}

.form-input {
  width: 100%;
  padding: 14px 48px 14px 16px;
  border: 2px solid var(--gray-200);
  border-radius: 10px;
  font-size: 15px;
  transition: var(--transition-fast);
  background: var(--surface-white);
  color: var(--gray-900);
}

.form-input::placeholder {
  color: var(--gray-400);
  opacity: 1;
}

.form-input:focus {
  border-color: var(--primary-400);
  box-shadow: var(--shadow-input);
  padding-right: 42px;
}

.form-input-icon {
  position: absolute;
  right: 16px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--gray-400);
  pointer-events: none;
  transition: var(--transition-fast);
}

.form-input:focus + .form-input-icon {
  color: var(--primary-600);
}


.form-options {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin: 24px 0;
}

.checkbox-group {
  display: flex;
  align-items: center;
  cursor: pointer;
}

.checkbox-custom {
  position: relative;
  width: 20px;
  height: 20px;
  border: 2px solid var(--gray-300);
  border-radius: 6px;
  margin-right: 10px;
  transition: var(--transition-fast);
}

.checkbox-custom::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 12px;
  height: 7px;
  border: 2px solid var(--surface-white);
  border-top: none;
  border-right: none;
  transform: translate(-50%, -60%) rotate(-45deg);
  opacity: 0;
  transition: var(--transition-fast);
}

input:checked + .checkbox-custom {
  background: var(--primary-600);
  border-color: var(--primary-600);
}

input:checked + .checkbox-custom::after {
  opacity: 1;
}

.remember-text {
  color: var(--gray-600);
  font-size: 14px;
  user-select: none;
}

.forgot-password {
  color: var(--primary-600);
  text-decoration: none;
  font-size: 14px;
  transition: var(--transition-fast);
  position: relative;
}

.forgot-password::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background: currentColor;
  transition: var(--transition-medium);
}

.forgot-password:hover {
  color: var(--primary-400);
}

.forgot-password:hover::after {
  width: 100%;
}

.btn-login {
  width: 100%;
  padding: 16px;
  background: var(--primary-600);
  border: none;
  border-radius: 10px;
  color: var(--surface-white);
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-medium);
  position: relative;
  overflow: hidden;
}

.btn-login::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 300%;
  height: 300%;
  transition: var(--transition-medium);
  opacity: 0;
}

.btn-login:hover {
  background: var(--primary-500);
  box-shadow: var(--shadow-md);
}

.btn-login:hover::before {
  opacity: 1;
  width: 100%;
  height: 100%;
}

.btn-login:active {
  transform: scale(0.98);
  box-shadow: var(--shadow-sm);
}

.btn-login i {
  margin-right: 10px;
  transition: var(--transition-fast);
}

.btn-login:hover i {
  transform: translateX(3px);
}


.modal {
  position: fixed;
  top: 200px;
  left: 500px;
  width: 100%;
  height: 100%;
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  animation: fadeIn 0.3s ease-out;
}

.modal-content {
  background: var(--surface-white);
  border-radius: 16px;
  padding: 25px;
  width: 330px;
  height: 200px;
  text-align: center;
  position: relative;
  transform: translateY(20px);
  opacity: 0;
  animation: modalIn 0.3s 0.1s ease-out forwards;
  box-shadow: var(--shadow-lg);
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes modalIn {
  0% {
    opacity: 0;
    transform: translateY(20px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 480px) {
  .modal-content {
    width: 90%;
    padding: 24px;
    margin: 12px;
  }
}

.modal-header {
  margin-bottom: 24px;
  position: relative;
}

.modal-icon {
  width: 60px;
  height: 60px;
  background: var(--error-500);
  border-radius: 50%;
  display: grid;
  place-items: center;
  margin: 0 auto 16px;
  animation: iconShake 0.6s ease-out;
}

.modal-icon svg {
  width: 28px;
  height: 28px;
  stroke-width: 2px;
  color: white;
}

@keyframes iconShake {
  0%, 100% { transform: rotate(0deg); }
  25% { transform: rotate(15deg); }
  50% { transform: rotate(-15deg); }
  75% { transform: rotate(5deg); }
}

.modal-title {
  color: var(--error-500);
  margin-bottom: 16px;
  font-size: 20px;
  font-weight: 600;
  line-height: 1.3;
}

.modal-body {
  color: var(--gray-600);
  font-size: 15px;
  line-height: 1.5;
  margin-bottom: 24px;
}

.login-footer {
  text-align: left;
  color: var(--gray-600);
  font-size: 14px;
}

.login-footer a {
  color: var(--primary-600);
  text-decoration: none;
  transition: var(--transition-fast);
}

.login-footer a:hover {
  color: var(--primary-400);
  text-decoration: underline;
}

.brand-footer {
  color: rgba(255,255,255,0.6);
  font-size: 13px;
  text-align: center;
  margin-top: 24px;
}