/* Tema Glassmorphism Oscuro Mejorado - OweMe */

:root {
  --primary: #a78bfa;
  --primary-dark: #8b5cf6;
  --secondary: #ec4899;
  --bg: #0a0514;
  --bg-light: rgba(255, 255, 255, 0.05);
  --bg-lighter: rgba(255, 255, 255, 0.1);
  --glass: rgba(255, 255, 255, 0.06);
  --glass-border: rgba(255, 255, 255, 0.12);
  --text: #f1f5f9;
  --text-muted: #94a3b8;
  --border: rgba(255, 255, 255, 0.08);
  --success: #34d399;
  --danger: #f87171;
  --warning: #fbbf24;
  --shadow: rgba(0, 0, 0, 0.4);
  --shadow-lg: rgba(0, 0, 0, 0.6);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  background-attachment: fixed;
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  position: relative;
}

body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(circle at 20% 50%, rgba(168, 85, 247, 0.12) 0%, transparent 50%),
    radial-gradient(circle at 80% 80%, rgba(236, 72, 153, 0.12) 0%, transparent 50%),
    radial-gradient(circle at 40% 20%, rgba(59, 130, 246, 0.08) 0%, transparent 50%);
  pointer-events: none;
  z-index: 0;
}

.container {
  max-width: 600px;
  margin: 0 auto;
  padding: 20px;
  position: relative;
  z-index: 1;
}

.hero {
  text-align: center;
  margin: 60px 0 40px;
}

.hero h1 {
  font-size: 3.5rem;
  margin-bottom: 10px;
  background: linear-gradient(135deg, #a78bfa, #ec4899);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  font-weight: 800;
  letter-spacing: -0.03em;
  filter: drop-shadow(0 0 30px rgba(167, 139, 250, 0.4));
  position: relative;
}

.hero h1::before {
  content: '';
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 120%;
  height: 120%;
  background: radial-gradient(circle, rgba(167, 139, 250, 0.15) 0%, transparent 70%);
  z-index: -1;
  animation: pulse 3s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { transform: translate(-50%, -50%) scale(1); opacity: 0.5; }
  50% { transform: translate(-50%, -50%) scale(1.1); opacity: 0.8; }
}

.subtitle {
  color: var(--text-muted);
  font-size: 1.1rem;
  font-weight: 500;
}

.actions {
  display: flex;
  gap: 15px;
  margin: 30px 0;
}

.btn {
  flex: 1;
  padding: 16px 32px;
  border: none;
  border-radius: 16px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  text-align: center;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  backdrop-filter: blur(10px);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
  transition: left 0.5s;
}

.btn:hover::before {
  left: 100%;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  box-shadow: 0 4px 20px rgba(167, 139, 250, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(167, 139, 250, 0.5);
}

.btn-secondary {
  background: var(--glass);
  color: var(--text);
  border: 2px solid var(--glass-border);
}

.btn-secondary:hover {
  background: var(--bg-lighter);
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 20px var(--shadow);
}

.features {
  display: grid;
  gap: 20px;
  margin-top: 50px;
}

.feature {
  background: var(--glass);
  backdrop-filter: blur(10px);
  padding: 30px;
  border-radius: 20px;
  border: 1px solid var(--glass-border);
  transition: all 0.3s;
}

.feature:hover {
  transform: translateY(-4px);
  background: var(--bg-lighter);
  box-shadow: 0 8px 30px var(--shadow-lg);
}

.feature .icon {
  font-size: 2.5rem;
  display: block;
  margin-bottom: 15px;
  filter: drop-shadow(0 0 10px currentColor);
}

.feature h3 {
  margin-bottom: 8px;
  color: var(--primary);
  font-weight: 700;
}

.feature p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.form-container {
  max-width: 420px;
  margin: 60px auto;
  padding: 20px;
}

.form-box {
  background: var(--glass);
  backdrop-filter: blur(20px);
  padding: 40px;
  border-radius: 24px;
  border: 1px solid var(--glass-border);
  box-shadow: 0 8px 32px var(--shadow-lg);
}

.form-box h2 {
  text-align: center;
  margin-bottom: 30px;
  color: var(--primary);
  font-weight: 700;
  font-size: 1.75rem;
}

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

.form-group label {
  display: block;
  margin-bottom: 8px;
  color: var(--text);
  font-size: 0.9rem;
  font-weight: 600;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 14px 16px;
  background: var(--bg-light);
  backdrop-filter: blur(10px);
  border: 2px solid var(--border);
  border-radius: 12px;
  color: var(--text);
  font-size: 1rem;
  transition: all 0.3s;
}

.form-group input::placeholder {
  color: var(--text-muted);
  opacity: 0.6;
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary);
  background: var(--bg-lighter);
  box-shadow: 0 0 0 4px rgba(167, 139, 250, 0.15);
}

.form-group input[type="checkbox"] {
  width: auto;
  margin-right: 8px;
  cursor: pointer;
  accent-color: var(--primary);
}

.form-group input[type="file"] {
  cursor: pointer;
  background: var(--glass);
  color: var(--text);
}

.error {
  background: rgba(248, 113, 113, 0.15);
  backdrop-filter: blur(10px);
  border: 2px solid var(--danger);
  color: var(--danger);
  padding: 14px;
  border-radius: 12px;
  margin-bottom: 20px;
  font-size: 0.9rem;
  font-weight: 500;
}

.success {
  background: rgba(52, 211, 153, 0.15);
  backdrop-filter: blur(10px);
  border: 2px solid var(--success);
  color: var(--success);
  padding: 14px;
  border-radius: 12px;
  margin-bottom: 20px;
  font-size: 0.9rem;
  font-weight: 500;
}

/* --- SECCIÓN HEADER PRINCIPAL --- */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 24px;
  background: var(--glass);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--glass-border);
  margin-bottom: 20px;
  position: relative;
  z-index: 1;
}

.header h2 {
  color: var(--primary);
  font-weight: 700;
  font-size: 1.5rem;
}

.btn-logout {
  padding: 10px 20px;
  background: var(--bg-lighter);
  backdrop-filter: blur(10px);
  border: 2px solid var(--glass-border);
  border-radius: 12px;
  color: var(--text);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s;
}

.btn-logout:hover {
  border-color: var(--primary);
  background: var(--glass);
  transform: translateY(-2px);
}

.session-list {
  display: grid;
  gap: 16px;
}

.session-card {
  background: var(--glass);
  backdrop-filter: blur(10px);
  padding: 24px;
  border-radius: 20px;
  border: 2px solid var(--glass-border);
  cursor: pointer;
  transition: all 0.3s;
  text-decoration: none;
  color: var(--text);
}

.session-card:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
  background: var(--bg-lighter);
  box-shadow: 0 8px 30px var(--shadow-lg);
}

.session-card h3 {
  margin-bottom: 8px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text);
}

.session-card .code {
  color: var(--primary);
  font-family: 'Monaco', 'Courier New', monospace;
  font-size: 1.2rem;
  font-weight: 700;
  background: var(--bg-light);
  padding: 4px 12px;
  border-radius: 8px;
  backdrop-filter: blur(5px);
}

/* --- MODALES --- */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  z-index: 1000;
  align-items: center;
  justify-content: center;
}

.modal.active {
  display: flex;
}

.modal-content {
  background: var(--glass);
  backdrop-filter: blur(20px);
  padding: 32px;
  border-radius: 24px;
  max-width: 420px;
  width: 90%;
  border: 1px solid var(--glass-border);
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 20px 60px var(--shadow-lg);
}

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

.modal-header h3 {
  font-weight: 700;
  font-size: 1.5rem;
  color: var(--text);
}

.modal-close {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 4px;
  transition: all 0.2s;
}

.modal-close:hover {
  color: var(--text);
  transform: rotate(90deg);
}

/* --- LISTADO DE GASTOS CORREGIDO --- */
.expense-list {
  display: grid;
  gap: 12px;
  margin-top: 20px;
}

.expense-item {
  background: var(--glass);
  backdrop-filter: blur(10px);
  padding: 18px;
  border-radius: 16px;
  border: 2px solid var(--glass-border);
  transition: all 0.3s;
}

.expense-item:hover {
  border-color: var(--primary);
  background: var(--bg-lighter);
  transform: translateX(4px);
}

/* Esta regla anula específicamente el fondo en los títulos de gastos */
.expense-item .header {
  display: flex !important;
  justify-content: space-between !important;
  padding: 0 !important;
  border: none !important;
  margin: 0 0 12px 0 !important;
  background: transparent !important;
  backdrop-filter: none !important;
  box-shadow: none !important;
  min-height: auto !important;
}

.expense-item .concept {
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--text);
}

.expense-item .amount {
  color: var(--primary);
  font-weight: 700;
  font-size: 1.15rem;
}

.expense-item .payer {
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  margin-bottom: 8px;
}

/* --- BALANCES --- */
.balance-section {
  background: var(--glass);
  backdrop-filter: blur(10px);
  padding: 24px;
  border-radius: 20px;
  border: 2px solid var(--glass-border);
  margin-bottom: 20px;
}

.balance-section h3 {
  color: var(--primary);
  margin-bottom: 16px;
  font-weight: 700;
  font-size: 1.25rem;
}

.balance-item {
  display: flex;
  justify-content: space-between;
  padding: 12px 0;
  border-bottom: 2px solid var(--border);
}

.balance-item:last-child {
  border-bottom: none;
}

.balance-item strong {
  color: var(--text);
}

.transaction-item {
  background: var(--bg-light);
  backdrop-filter: blur(10px);
  padding: 16px;
  border-radius: 12px;
  border-left: 4px solid var(--warning);
  margin-bottom: 10px;
  font-weight: 500;
  color: var(--text);
}

/* --- OTROS ESTILOS --- */
.form-group select {
  appearance: none;
  background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='rgb(167, 139, 250)' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 20px;
  padding-right: 40px;
}

.form-group select option {
  background: var(--bg);
  color: var(--text);
}

::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-light);
  border-radius: 10px;
}

::-webkit-scrollbar-thumb {
  background: var(--primary);
  border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--primary-dark);
}

#splitInputs input {
  background: var(--bg-light) !important;
  border-color: var(--border) !important;
  color: var(--text) !important;
}

#splitInputs input:focus {
  border-color: var(--primary) !important;
  background: var(--bg-lighter) !important;
}

#splitInputs button {
  background: var(--glass) !important;
  color: var(--text) !important;
  border: 2px solid var(--glass-border) !important;
}

#splitInputs button:hover {
  background: var(--bg-lighter) !important;
  border-color: var(--primary) !important;
}

p, span, div, label {
  color: var(--text);
}

img {
  border: 2px solid var(--glass-border);
}

@media (max-width: 600px) {
  .hero h1 {
    font-size: 2.5rem;
  }
  
  .form-box {
    padding: 30px 20px;
  }

  .modal-content {
    padding: 24px;
  }
}

/* Spinner de carga */
.spinner {
  width: 20px;
  height: 20px;
  border: 3px solid var(--bg-light);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Animaciones para notificaciones */
@keyframes slideIn {
  from {
    transform: translateX(400px);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

@keyframes slideOut {
  from {
    transform: translateX(0);
    opacity: 1;
  }
  to {
    transform: translateX(400px);
    opacity: 0;
  }
}