* {
  font-family: "Roboto", sans-serif;
}
body {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0;
  padding: 1rem;
}

/* === CONTAINER CHÍNH === */
.login-wrapper {
  background: white;
  border-radius: 16px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
  overflow: hidden;
  width: 100%;
  max-width: 420px;
  animation: fadeIn 0.6s ease-out;
}

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

/* === HEADER === */
.login-header {
  text-align: center;
  padding: 1.8rem 1rem 1rem;
  background: #f8f9fa;
}
.login-header h1 {
  margin: 0;
  font-size: 1.9rem;
  color: #1a1a1a;
  font-weight: 700;
}
.login-header p {
  margin: 0.5rem 0 0;
  color: #666;
  font-size: 0.95rem;
}

/* === TABS === */
.login-tabs {
  display: flex;
  background: #f1f3f5;
}
.tab {
  flex: 1;
  padding: 1rem;
  text-align: center;
  cursor: pointer;
  font-weight: 600;
  transition: all 0.3s;
  position: relative;
  color: #555;
}
.tab:hover {
  background: #e9ecef;
}
.tab.active {
  background: white;
  color: #10b981;
}
.tab.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: #10b981;
  border-radius: 2px;
}

/* === FORM === */
.form-container {
  padding: 2rem;
}
.form-group {
  margin-bottom: 1.1rem;
}
label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: #444;
  font-size: 0.95rem;
}
input {
  width: 100%;
  padding: 0.85rem 1rem;
  border: 1.5px solid #ddd;
  border-radius: 10px;
  font-size: 1rem;
  transition: all 0.3s;
  background: #fafafa;
}
input:focus {
  outline: none;
  border-color: #10b981;
  background: white;
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.1);
}

/* === NÚT === */
button {
  width: 100%;
  padding: 0.9rem;
  background: #10b981;
  color: white;
  border: none;
  border-radius: 10px;
  font-weight: 600;
  font-size: 1.1rem;
  cursor: pointer;
  transition: all 0.3s;
  margin-top: 0.5rem;
}
button:hover {
  background: #059669;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}
button:active {
  transform: translateY(0);
}

/* === THÔNG BÁO === */
.error,
.success {
  font-size: 0.9rem;
  margin-top: 0.5rem;
  text-align: center;
  padding: 0.5rem;
  border-radius: 6px;
}
.error {
  color: #ef4444;
  background: #fee2e2;
}
.success {
  color: #10b981;
  background: #d1fae5;
}

/* === LIÊN KẾT === */
.link {
  text-align: center;
  margin-top: 1.2rem;
  color: #666;
  font-size: 0.95rem;
}
.link a {
  color: #10b981;
  text-decoration: none;
  font-weight: 500;
}
.link a:hover {
  text-decoration: underline;
}

/* === DARK MODE === */
body.dark-mode .login-wrapper {
  background: #1a1a1a;
  color: #e0e0e0;
}
body.dark-mode .login-header {
  background: #2d2d2d;
}
body.dark-mode input {
  background: #2d2d2d;
  border-color: #444;
  color: #e0e0e0;
}
body.dark-mode .tab {
  color: #ccc;
}
body.dark-mode .tab.active {
  background: #1a1a1a;
}
body.dark-mode .link {
  color: #aaa;
}