/* ======================
   Base Styles
   ====================== */
:root {
  /* Green theme (AES) */
  --primary: #059669;
  --primary-dark: #047857;
  --primary-light: #10b981;
  --bg-light: #f0fdf4;
  --card-bg: #ffffff;
  
  /* Purple theme (Cipher) */
  --purple-primary: #4f46e5;
  --purple-dark: #4338ca;
  --purple-light: #6366f1;
  --purple-bg: #f8fafc;
}

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

body {
  font-family: system-ui, -apple-system, sans-serif;
  color: #1e293b;
  min-height: 100vh;
}

/* ======================
   Navbar
   ====================== */
.navbar {
  padding: 1rem;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
}

.navbar-green {
  background: linear-gradient(90deg, var(--primary), var(--primary-dark));
}

.navbar-purple {
  background: linear-gradient(90deg, var(--purple-primary), var(--purple-dark));
}

.navbar-brand {
  font-size: 1.25rem;
  font-weight: 600;
}

/* ======================
   Cards
   ====================== */
.card {
  border: none;
  border-radius: 16px;
  background: var(--card-bg);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.12);
}

.card-header {
  background: linear-gradient(90deg, #f8fafc, #f1f5f9);
  border-bottom: 1px solid #e2e8f0;
  font-weight: 600;
  padding: 1rem 1.25rem;
}

.card-header.green {
  background: linear-gradient(90deg, #f0fdf4, #d1fae5);
  border-bottom-color: #a7f3d0;
  color: var(--primary-dark);
}

.card-header.purple {
  background: linear-gradient(90deg, #f8fafc, #f1f5f9);
  border-bottom-color: #e2e8f0;
  color: var(--purple-primary);
}

.card-body {
  padding: 1.25rem;
}

/* ======================
   Forms
   ====================== */
.form-control, .form-select {
  border-radius: 10px;
  border: 1px solid #cbd5e1;
  padding: 12px;
  font-size: 1rem;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.form-control:focus, .form-select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 0.2rem rgba(5, 150, 105, 0.25);
}

textarea.form-control {
  border-radius: 12px;
  min-height: 180px;
  resize: vertical;
}

.input-group-text {
  border-radius: 10px 0 0 10px;
  border: 1px solid #cbd5e1;
  background: #f8fafc;
}

/* ======================
   Buttons
   ====================== */
.btn {
  border-radius: 10px;
  padding: 10px 24px;
  font-weight: 600;
  transition: all 0.3s ease;
}

.btn-primary-custom {
  background: linear-gradient(90deg, var(--primary), var(--primary-dark));
  border: none;
  color: white;
}

.btn-primary-custom:hover {
  background: linear-gradient(90deg, var(--primary-dark), var(--primary));
  color: white;
  transform: translateY(-2px);
}

.btn-purple {
  background: linear-gradient(135deg, #7c3aed, #6d28d9);
  border: none;
  color: white;
}

.btn-purple:hover {
  background: linear-gradient(135deg, #6d28d9, #7c3aed);
  color: white;
}

.btn-outline-light {
  border-color: rgba(255, 255, 255, 0.5);
}

.btn-outline-light:hover {
  background: rgba(255, 255, 255, 0.2);
  border-color: white;
}

.btn-check:checked + .btn {
  background-color: var(--purple-primary);
  border-color: var(--purple-primary);
  color: white;
}

/* ======================
   Alphabet Box (Caesar Visual)
   ====================== */
.alphabet-box {
  font-family: 'Courier New', monospace;
  background: linear-gradient(135deg, #f1f5f9, #e2e8f0);
  border: 2px dashed var(--purple-light);
  border-radius: 12px;
  padding: 1.25rem;
  text-align: center;
  font-size: 1.1rem;
  color: #334155;
  line-height: 1.8;
}

/* ======================
   Alerts
   ====================== */
.alert {
  border-radius: 12px;
  border: none;
}

.alert-danger {
  background: #fef2f2;
  color: #dc2626;
}

.alert-warning {
  background: #fffbeb;
  color: #d97706;
}

.alert-success {
  background: #f0fdf4;
  color: #059669;
}

/* ======================
   Info Box
   ====================== */
.info-box {
  background: linear-gradient(135deg, #dbeafe, #bfdbfe);
  border-radius: 12px;
  padding: 20px;
  border-left: 4px solid #3b82f6;
}

.step-box {
  background: #f0fdf4;
  border-radius: 10px;
  padding: 15px;
  margin-bottom: 10px;
  border: 1px solid #bbf7d0;
}

.step-number {
  background: var(--primary);
  color: white;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  margin-right: 10px;
}

/* ======================
   Modal
   ====================== */
.modal-content {
  border: none;
  border-radius: 16px;
  box-shadow: 0 25px 50px rgba(0, 0, 0, 0.25);
}

.modal-header {
  border-radius: 16px 16px 0 0;
  padding: 1.25rem;
}

.modal-header.green {
  background: linear-gradient(90deg, var(--primary), var(--primary-dark));
}

.modal-header.purple {
  background: linear-gradient(90deg, var(--purple-primary), var(--purple-dark));
}

.modal-body {
  padding: 1.5rem;
}

.modal-footer {
  border-top: 1px solid #e2e8f0;
  padding: 1rem 1.5rem;
}

/* ======================
   Backgrounds
   ====================== */
.bg-gradient-green {
  background: linear-gradient(135deg, #f0fdf4, #d1fae5);
}

.bg-gradient-purple {
  background: linear-gradient(135deg, #f8fafc, #e2e8f0);
}

/* ======================
   Responsive
   ====================== */
@media (max-width: 991px) {
  .card {
    margin-bottom: 1rem;
  }
  
  .card:hover {
    transform: none;
  }
}

/* ======================
   Utilities
   ====================== */
.form-label {
  font-weight: 600;
  font-size: 0.875rem;
  color: #475569;
  margin-bottom: 0.5rem;
}

small.text-muted {
  font-size: 0.8rem;
}

.btn-group .btn {
  flex: 1;
}

.d-flex.justify-content-between.align-items-center {
  gap: 10px;
}