/* ===== Základní styly ===== */
:root {
  --primary-color: #3498db;
  --primary-dark: #2980b9;
  --secondary-color: #2ecc71;
  --danger-color: #e74c3c;
  --warning-color: #f39c12;
  --info-color: #3498db;
  --light-color: #ecf0f1;
  --dark-color: #2c3e50;
  --text-color: #333;
  --text-light: #7f8c8d;
  --border-color: #ddd;
  --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  --border-radius: 8px;
}

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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background-color: #f8f9fa;
  padding: 20px;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}

header {
  text-align: center;
  margin-bottom: 30px;
}

header h1 {
  color: var(--dark-color);
  margin-bottom: 10px;
  font-size: 2.5rem;
}

.subtitle {
  color: var(--text-light);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto;
}

/* ===== Sekce ===== */
.section {
  background: white;
  border-radius: var(--border-radius);
  padding: 25px;
  margin-bottom: 20px;
  box-shadow: var(--shadow);
}

.section h2 {
  color: var(--dark-color);
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-color);
  font-size: 1.3rem;
}

/* ===== Formuláře ===== */
.form-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
}

.form-group {
  margin-bottom: 15px;
}

.form-group.full-width {
  grid-column: 1 / -1;
}

.form-group label {
  display: block;
  margin-bottom: 5px;
  font-weight: 600;
  color: var(--text-color);
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  font-size: 14px;
  transition: border 0.3s;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary-color);
}

.form-group textarea {
  min-height: 80px;
  resize: vertical;
}

/* ===== Položky faktury ===== */
#items-container {
  margin-bottom: 15px;
}

.item {
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 15px;
  margin-bottom: 15px;
  background-color: #f9f9f9;
  position: relative;
}

.item-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
}

.item-header h3 {
  font-size: 1rem;
  color: var(--dark-color);
}

.remove-item {
  background: var(--danger-color);
  color: white;
  border: none;
  border-radius: 50%;
  width: 30px;
  height: 30px;
  cursor: pointer;
  font-size: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.3s;
}

.remove-item:hover {
  background: #c0392b;
}

.item-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 10px;
}

/* ===== Tlačítka ===== */
.btn {
  padding: 10px 20px;
  border: none;
  border-radius: var(--border-radius);
  font-size: 14px;
  cursor: pointer;
  transition: all 0.3s;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.btn-primary {
  background-color: var(--primary-color);
  color: white;
}

.btn-primary:hover {
  background-color: var(--primary-dark);
}

.btn-success {
  background-color: var(--secondary-color);
  color: white;
}

.btn-success:hover {
  background: #27ae60;
}

.btn-info {
  background-color: var(--info-color);
  color: white;
}

.btn-info:hover {
  background: #2980b9;
}

.btn-warning {
  background-color: var(--warning-color);
  color: white;
}

.btn-warning:hover {
  background: #d35400;
}

.btn-danger {
  background-color: var(--danger-color);
  color: white;
}

.btn-danger:hover {
  background: #c0392b;
}

.btn-secondary {
  background-color: var(--light-color);
  color: var(--text-color);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background: #d5dbdb;
}

.btn-small {
  padding: 5px 10px;
  font-size: 12px;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 10px;
}

/* ===== Historie faktur ===== */
.search-box {
  margin-bottom: 15px;
}

.search-box input {
  width: 100%;
  padding: 10px;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  font-size: 14px;
}

.invoices-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 15px;
}

.invoice-card {
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 15px;
  background: white;
  cursor: pointer;
  transition: all 0.3s;
}

.invoice-card:hover {
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  transform: translateY(-2px);
}

.invoice-card h3 {
  color: var(--primary-color);
  margin-bottom: 10px;
  font-size: 1.1rem;
}

.invoice-card p {
  margin: 5px 0;
  font-size: 14px;
}

.invoice-card .customer {
  font-weight: 600;
}

.invoice-card .date {
  color: var(--text-light);
  font-size: 13px;
}

/* ===== Modal (Náhled faktury) ===== */
.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  overflow: auto;
}

.modal-content {
  background-color: white;
  margin: 50px auto;
  padding: 20px;
  border-radius: var(--border-radius);
  width: 90%;
  max-width: 900px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 5px 20px rgba(0, 0, 0, 0.3);
  position: relative;
}

.close {
  position: absolute;
  right: 20px;
  top: 15px;
  font-size: 28px;
  font-weight: bold;
  cursor: pointer;
  color: var(--text-light);
}

.close:hover {
  color: var(--dark-color);
}

.modal-actions {
  display: flex;
  gap: 10px;
  margin-top: 20px;
  justify-content: center;
}

/* ===== Faktura (Náhled) ===== */
#preview-content {
  padding: 20px;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  background: white;
}

.invoice-preview {
  max-width: 800px;
  margin: 0 auto;
}

.invoice-header {
  text-align: center;
  margin-bottom: 30px;
}

.invoice-header h1 {
  font-size: 2rem;
  margin-bottom: 5px;
}

.invoice-meta {
  display: flex;
  justify-content: space-between;
  margin-bottom: 30px;
}

.invoice-meta div {
  flex: 1;
}

.invoice-meta h2 {
  font-size: 1.2rem;
  margin-bottom: 10px;
  color: var(--dark-color);
}

.invoice-meta p {
  margin: 5px 0;
}

.invoice-table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 20px;
}

.invoice-table th,
.invoice-table td {
  border: 1px solid var(--border-color);
  padding: 10px;
  text-align: left;
}

.invoice-table th {
  background-color: var(--light-color);
  font-weight: 600;
}

.invoice-table tr:nth-child(even) {
  background-color: #f9f9f9;
}

.invoice-total {
  margin-top: 20px;
  text-align: right;
}

.invoice-total p {
  margin: 5px 0;
  font-size: 1.1rem;
}

.invoice-total .total {
  font-weight: bold;
  font-size: 1.3rem;
}

.invoice-notes {
  margin-top: 30px;
  padding-top: 20px;
  border-top: 1px solid var(--border-color);
  font-style: italic;
}

/* ===== Varování ===== */
.warning {
  background-color: #fff3cd;
  color: #856404;
  padding: 15px;
  border-radius: var(--border-radius);
  margin-bottom: 20px;
  border: 1px solid #ffeeba;
}

/* ===== Footer ===== */
footer {
  text-align: center;
  margin-top: 30px;
  padding: 20px;
  color: var(--text-light);
  font-size: 14px;
}

footer a {
  color: var(--primary-color);
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .form-grid {
    grid-template-columns: 1fr;
  }

  .item-grid {
    grid-template-columns: 1fr 1fr;
  }

  .invoice-meta {
    flex-direction: column;
    gap: 20px;
  }

  .modal-content {
    width: 95%;
    margin: 20px auto;
  }

  .actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }
}

/* ===== Tisk ===== */
@media print {
  body * {
    visibility: hidden;
  }

  #preview-content, #preview-content * {
    visibility: visible;
  }

  #preview-content {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    padding: 0;
  }

  .modal, .modal-actions, .close {
    display: none !important;
  }

  .invoice-table {
    page-break-inside: auto;
  }

  tr {
    page-break-inside: avoid;
    page-break-after: auto;
  }
}