:root {
  --color-bg: #f5f5f7;
  --color-surface: #ffffff;
  --color-text: #1e1e1e;
  --color-text-secondary: #6e6e73;
  --color-accent: #656f77;
  --color-border: rgba(0, 0, 0, 0.08);
  --color-border-hover: rgba(0, 0, 0, 0.15);
  --color-success: #34c759;
  --color-error: #ff3b30;
  --font-heading: Georgia, 'Times New Roman', serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --radius-lg: 16px;
  --radius-md: 12px;
  --shadow-soft: 0 2px 20px rgba(0, 0, 0, 0.06);
  --shadow-hover: 0 8px 40px rgba(0, 0, 0, 0.12);
}

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

html, body {
  overflow-x: hidden;
  width: 100%;
  max-width: 100vw;
}

body {
  font-family: var(--font-body);
  background: var(--color-bg);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

.particles-background {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  z-index: 0;
  pointer-events: none;
}

.particle {
  position: absolute;
  background: rgba(101, 111, 119, 0.06);
  border: 1px solid rgba(101, 111, 119, 0.04);
  border-radius: 50%;
  animation: floatParticle 20s infinite;
}

.particle:nth-child(1) { width: 60px; height: 60px; left: 10%; top: 20%; animation-delay: 0s; }
.particle:nth-child(2) { width: 40px; height: 40px; right: 15%; top: 30%; animation-delay: 2s; }
.particle:nth-child(3) { width: 80px; height: 80px; left: 70%; top: 60%; animation-delay: 4s; }
.particle:nth-child(4) { width: 50px; height: 50px; left: 30%; bottom: 20%; animation-delay: 1s; }
.particle:nth-child(5) { width: 35px; height: 35px; right: 25%; bottom: 30%; animation-delay: 3s; }
.particle:nth-child(6) { width: 55px; height: 55px; left: 50%; top: 10%; animation-delay: 5s; }
.particle:nth-child(7) { width: 45px; height: 45px; right: 40%; bottom: 15%; animation-delay: 2.5s; }
.particle:nth-child(8) { width: 65px; height: 65px; left: 20%; top: 70%; animation-delay: 4.5s; }
.particle:nth-child(9) { width: 30px; height: 30px; right: 10%; top: 50%; animation-delay: 1.5s; }
.particle:nth-child(10) { width: 50px; height: 50px; left: 60%; bottom: 40%; animation-delay: 3.5s; }

@keyframes floatParticle {
  0%, 100% {
    transform: translate(0, 0) rotate(0deg);
    opacity: 0.4;
  }
  25% {
    transform: translate(30px, -40px) rotate(45deg);
    opacity: 0.6;
  }
  50% {
    transform: translate(-20px, -60px) rotate(90deg);
    opacity: 0.5;
  }
  75% {
    transform: translate(-40px, -30px) rotate(135deg);
    opacity: 0.5;
  }
}

.classroom-login-container {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: stretch;
  width: 90%;
  max-width: 1000px;
  min-height: 720px;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-hover);
  overflow: hidden;
  animation: fadeInUp 0.6s ease;
}

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

.login-left-panel {
  flex: 1;
  background-image: url('../../images/STOCK4.jpg');
  background-size: cover;
  background-position: center;
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 48px 40px;
  color: white;
  overflow: hidden;
  align-self: stretch;
}

.login-left-panel::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(to top, rgba(30, 30, 30, 0.85) 0%, rgba(30, 30, 30, 0.5) 50%, rgba(30, 30, 30, 0.3) 100%);
  z-index: 1;
}

.login-left-panel::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
  transition: backdrop-filter 0.5s ease;
  z-index: 2;
}

.login-left-panel:hover::after {
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}

.brand-section {
  position: relative;
  z-index: 3;
}

.brand-logo {
  width: 90px;
  height: 90px;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 28px;
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  position: relative;
  overflow: visible;
}

.brand-logo::before {
  content: '';
  position: absolute;
  top: -2px;
  left: -2px;
  width: calc(100% + 4px);
  height: calc(100% + 4px);
  border: 2px solid rgba(255, 255, 255, 0.6);
  border-radius: 24px;
  animation: brandAuraShoot 2.5s ease-out infinite;
  pointer-events: none;
  box-sizing: border-box;
}

.brand-logo::after {
  content: '';
  position: absolute;
  top: -2px;
  left: -2px;
  width: calc(100% + 4px);
  height: calc(100% + 4px);
  border: 2px solid rgba(255, 255, 255, 0.4);
  border-radius: 24px;
  animation: brandAuraShoot 2.5s ease-out 1.25s infinite;
  pointer-events: none;
  box-sizing: border-box;
}

@keyframes brandAuraShoot {
  0% {
    transform: scale(1);
    opacity: 0.8;
  }
  100% {
    transform: scale(1.5);
    opacity: 0;
  }
}

.brand-logo i, .brand-logo svg {
  width: 44px;
  height: 44px;
  color: white;
  stroke-width: 1.5;
}

@keyframes brandIconFloat {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-4px);
  }
}

.brand-section h1 {
  text-align: center;
  font-family: var(--font-heading);
  font-size: 2.75rem;
  font-weight: 400;
  margin-bottom: 12px;
  letter-spacing: -0.5px;
}

.brand-subtitle {
  text-align: center;
  font-family: var(--font-body);
  font-size: 1.15rem;
  opacity: 0.85;
  font-weight: 400;
}

.features-section {
  position: relative;
  z-index: 3;
  margin-top: 48px;
}

.feature-item {
  display: flex;
  align-items: flex-start;
  gap: 18px;
  margin-bottom: 16px;
  padding: 18px 20px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 14px;
  backdrop-filter: blur(10px);
  transition: all 0.2s ease;
}

.feature-item:hover {
  background: rgba(255, 255, 255, 0.12);
  transform: translateX(4px);
}

.feature-icon {
  width: 48px;
  height: 48px;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.feature-icon i, .feature-icon svg {
  width: 24px;
  height: 24px;
  color: white;
  stroke-width: 1.5;
}

.feature-content h3 {
  font-family: var(--font-body);
  font-size: 1.1rem;
  font-weight: 500;
  margin-bottom: 6px;
}

.feature-content p {
  font-size: 0.9rem;
  opacity: 0.75;
  line-height: 1.4;
}

.decorative-elements {
  display: none;
}

.login-right-panel {
  flex: 1;
  padding: 48px 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface);
}

.login-form-container {
  width: 100%;
  max-width: 380px;
}

.welcome-header {
  margin-bottom: 32px;
}

.welcome-header h2 {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  font-weight: 400;
  color: var(--color-text);
  margin-bottom: 8px;
  letter-spacing: -0.5px;
}

.welcome-header p {
  font-family: var(--font-body);
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  line-height: 1.5;
}

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

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: 8px;
}

.form-group label i, .form-group label svg {
  width: 16px;
  height: 16px;
  color: rgba(147, 161, 173, 0.75);
  stroke-width: 1.5;
}

.input-wrapper {
  position: relative;
}

.input-with-icon {
  display: flex;
  align-items: center;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all 0.2s ease;
}

.input-with-icon:focus-within {
  border-color: rgba(147, 161, 173, 0.65);
  box-shadow: 0 0 0 3px rgba(147, 161, 173, 0.18);
  background: var(--color-surface);
}

.input-prefix {
  position: absolute;
  right: 14px;
  left: auto;
  top: 50%;
  transform: translateY(-50%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-secondary);
  pointer-events: none;
  z-index: 2;
}

.input-prefix i,
.input-prefix svg {
  width: 18px;
  height: 18px;
  stroke-width: 1.5;
  display: block;
}

.input-with-icon:focus-within .input-prefix {
  color: rgba(147, 161, 173, 0.9);
}

.input-with-icon {
  position: relative;
}

.input-with-icon input {
  border: none !important;
  background: transparent !important;
  box-shadow: none !important;
  padding: 14px 44px 14px 16px;
  width: 100%;
}

.input-with-icon input:focus {
  outline: none;
  box-shadow: none !important;
}

.input-wrapper input {
  width: 100%;
  padding: 14px 44px 14px 16px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 0.95rem;
  color: var(--color-text);
  background: var(--color-bg);
  transition: all 0.2s ease;
}

.input-wrapper input:focus {
  outline: none;
  border-color: rgba(147, 161, 173, 0.65);
  background: var(--color-surface);
  box-shadow: 0 0 0 3px rgba(147, 161, 173, 0.18);
}

.input-wrapper input::placeholder {
  color: var(--color-text-secondary);
}

.input-wrapper .input-icon {
  position: absolute;
  right: 14px;
  top: 50%;
  transform: translateY(-50%);
  pointer-events: none;
}

.input-wrapper .input-icon i, .input-wrapper .input-icon svg {
  width: 18px;
  height: 18px;
  color: var(--color-text-secondary);
  stroke-width: 1.5;
}

.toggle-password {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-secondary);
  border-radius: 6px;
  transition: all 0.2s ease;
}

.toggle-password:hover {
  color: rgba(147, 161, 173, 0.9);
  background: var(--color-bg);
}

.toggle-password i, .toggle-password svg {
  width: 18px;
  height: 18px;
  stroke-width: 1.5;
}

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

.checkbox-container {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 0.875rem;
  color: var(--color-text-secondary);
}

.checkbox-container input {
  width: 16px;
  height: 16px;
  accent-color: var(--color-accent);
  cursor: pointer;
}

.forgot-password {
  font-size: 0.875rem;
  color: rgba(147, 161, 173, 0.9);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.forgot-password:hover {
  color: #93a1ad;
}

.login-message {
  min-height: 20px;
  margin-bottom: 16px;
  font-size: 0.875rem;
  text-align: center;
}

.login-message.success { color: var(--color-success); }
.login-message.error { color: var(--color-error); }

.btn-login {
  width: 100%;
  padding: 14px 24px;
  background: var(--color-text);
  color: var(--color-surface);
  border: none;
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  transition: all 0.2s ease;
}

.btn-login:hover {
  background: rgba(147, 161, 173, 0.15);
  color: #1a1a1a;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(147, 161, 173, 0.2);
}

.btn-login:active {
  transform: translateY(0);
}

.btn-login .btn-icon i, .btn-login .btn-icon svg {
  width: 18px;
  height: 18px;
  stroke-width: 2;
  transition: transform 0.2s ease;
}

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

.divider {
  margin: 28px 0;
  text-align: center;
  position: relative;
}

.divider::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--color-border);
}

.divider span {
  background: var(--color-surface);
  padding: 0 16px;
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  position: relative;
}

.alternative-actions {
  display: flex;
  gap: 12px;
  margin-bottom: 28px;
}

.btn-secondary {
  flex: 1;
  padding: 12px 16px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  color: var(--color-text-secondary);
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 500;
  text-decoration: none;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: all 0.2s ease;
}

.btn-secondary:hover {
  border-color: rgba(147, 161, 173, 0.65);
  color: var(--color-text);
  background: var(--color-bg);
}

.btn-secondary i, .btn-secondary svg {
  width: 16px;
  height: 16px;
  stroke-width: 1.5;
}

.login-footer {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
  margin-top: 8px;
}

.login-footer p {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  margin-bottom: 20px;
}

.login-footer a {
  color: rgba(147, 161, 173, 0.9);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.login-footer a:hover {
  color: rgba(147, 161, 173, 0.95);
}

.footer-links {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  font-size: 0.8rem;
}

.footer-links span {
  color: var(--color-border);
}

.footer-links a {
  color: var(--color-text-secondary);
  font-weight: 400;
}

.loader-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
}

.loader-overlay.show {
  opacity: 1;
  visibility: visible;
}

.loader-spinner {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
}

.spinner-circle {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-accent);
  animation: bounce 1.4s infinite ease-in-out;
}

.spinner-circle:nth-child(1) { animation-delay: -0.32s; }
.spinner-circle:nth-child(2) { animation-delay: -0.16s; }

@keyframes bounce {
  0%, 80%, 100% { transform: scale(0); }
  40% { transform: scale(1); }
}

.loader-text {
  font-size: 0.95rem;
  color: var(--color-text);
  font-weight: 500;
}

@media (max-width: 1024px) {
  .classroom-login-container {
    flex-direction: column;
    width: 95%;
    max-width: 480px;
    min-height: auto;
  }

  .login-left-panel {
    padding: 36px 32px;
    min-height: auto;
  }

  .features-section {
    display: none;
  }

  .login-right-panel {
    padding: 36px 32px;
  }
}

@media (max-width: 768px) {
  body {
    padding: 0;
    align-items: flex-start;
  }

  .classroom-login-container {
    width: 100%;
    max-width: 100%;
    border-radius: 0;
    border: none;
    box-shadow: none;
  }

  .login-left-panel {
    padding: 28px 24px;
    min-height: 180px;
  }

  .brand-logo {
    width: 52px;
    height: 52px;
    margin-bottom: 14px;
  }

  .brand-logo i, .brand-logo svg {
    width: 26px;
    height: 26px;
  }

  .brand-section h1 {
    font-size: 1.6rem;
  }

  .login-right-panel {
    padding: 28px 24px;
  }

  .welcome-header h2 {
    font-size: 1.5rem;
  }

  .particles-background .particle {
    display: none;
  }
}

@media (max-width: 480px) {
  .login-left-panel {
    padding: 24px 20px;
  }

  .brand-section h1 {
    font-size: 1.4rem;
  }

  .brand-subtitle {
    font-size: 0.9rem;
  }

  .login-right-panel {
    padding: 28px 20px 40px;
  }

  .welcome-header {
    margin-bottom: 24px;
  }

  .welcome-header h2 {
    font-size: 1.35rem;
  }

  .input-wrapper input {
    padding: 13px 44px 13px 14px;
    font-size: 16px;
  }

  .btn-login {
    padding: 13px 20px;
  }

  .alternative-actions {
    flex-direction: column;
    gap: 10px;
  }
}

@media (hover: none) and (pointer: coarse) {
  .btn-login:hover {
    transform: none;
    box-shadow: none;
  }

  .feature-item:hover {
    transform: none;
  }

  .btn-login:active {
    background: #333;
  }
}