/* ===================================
   Datei-Download-System - Professional Design
   100% Responsive | Modern Icons | Grid Layout
   =================================== */

:root {
  /* Farbschema - Professional & Modern */
  --primary: #4f46e5;
  --primary-hover: #4338ca;
  --primary-light: #6366f1;
  
  --secondary: #64748b;
  --secondary-hover: #475569;
  
  --accent: #8b5cf6;
  --accent-hover: #7c3aed;
  
  --background: #0f172a;
  --surface: #1e293b;
  --surface-hover: #334155;
  --surface-light: #475569;
  
  --text-primary: #f1f5f9;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  
  --success: #10b981;
  --error: #ef4444;
  --warning: #f59e0b;
  --info: #3b82f6;
  
  --border: #334155;
  --border-light: #475569;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 0.75rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===================================
   Reset & Base
   =================================== */

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--background);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ===================================
   Background Gradient
   =================================== */

.background-gradient {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  background: 
    radial-gradient(circle at 20% 30%, rgba(79, 70, 229, 0.15) 0%, transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(139, 92, 246, 0.15) 0%, transparent 50%),
    radial-gradient(circle at 50% 50%, rgba(99, 102, 241, 0.1) 0%, transparent 50%);
  animation: gradientShift 15s ease-in-out infinite;
}

@keyframes gradientShift {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.8; transform: scale(1.05); }
}

/* ===================================
   Container
   =================================== */

.container {
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

@media (max-width: 768px) {
  .container {
    padding: 0 var(--spacing-md);
  }
}

/* ===================================
   Header
   =================================== */

.header {
  background: rgba(30, 41, 59, 0.8);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: var(--spacing-lg) 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-md);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  text-decoration: none;
  transition: var(--transition-base);
}

.logo i {
  font-size: 1.5rem;
  color: var(--primary-light);
}

.logo:hover {
  color: var(--primary-light);
  transform: translateY(-2px);
}

@media (max-width: 640px) {
  .logo span {
    display: none;
  }
}

/* ===================================
   Main Content
   =================================== */

.main-content {
  flex: 1;
  padding: var(--spacing-2xl) 0;
}

/* ===================================
   Page Header
   =================================== */

.page-header {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
}

.page-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: var(--radius-2xl);
  margin-bottom: var(--spacing-lg);
  box-shadow: var(--shadow-xl);
}

.page-icon i {
  font-size: 2.5rem;
  color: white;
}

.page-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
  background: linear-gradient(135deg, var(--primary-light), var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.page-subtitle {
  font-size: 1.125rem;
  color: var(--text-muted);
}

@media (max-width: 768px) {
  .page-icon {
    width: 60px;
    height: 60px;
  }
  
  .page-icon i {
    font-size: 2rem;
  }
  
  .page-title {
    font-size: 2rem;
  }
  
  .page-subtitle {
    font-size: 1rem;
  }
}

/* ===================================
   Login
   =================================== */

.login-wrapper {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-xl) 0;
}

.login-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-2xl);
  padding: var(--spacing-2xl);
  width: 100%;
  max-width: 480px;
  box-shadow: var(--shadow-2xl);
  animation: fadeInUp 0.5s ease-out;
}

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

.login-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.logo-container {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: var(--radius-2xl);
  margin-bottom: var(--spacing-lg);
  box-shadow: var(--shadow-xl);
}

.logo-container i {
  font-size: 2.5rem;
  color: white;
}

.login-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
}

.login-subtitle {
  color: var(--text-muted);
  font-size: 1rem;
}

.login-footer {
  margin-top: var(--spacing-lg);
}

@media (max-width: 640px) {
  .login-card {
    padding: var(--spacing-xl);
  }
  
  .logo-container {
    width: 60px;
    height: 60px;
  }
  
  .logo-container i {
    font-size: 2rem;
  }
  
  .login-title {
    font-size: 1.75rem;
  }
}

/* ===================================
   Forms
   =================================== */

.login-form,
.form {
  margin-bottom: var(--spacing-lg);
}

.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-label {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  margin-bottom: var(--spacing-sm);
  font-weight: 500;
  color: var(--text-secondary);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.form-label i {
  font-size: 0.875rem;
  color: var(--primary-light);
}

.form-input {
  width: 100%;
  padding: var(--spacing-md) var(--spacing-lg);
  background: var(--background);
  border: 2px solid var(--border);
  border-radius: var(--radius-lg);
  color: var(--text-primary);
  font-size: 1rem;
  font-family: inherit;
  transition: var(--transition-base);
  outline: none;
}

.form-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

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

/* ===================================
   Buttons
   =================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: 1rem;
  font-weight: 600;
  font-family: inherit;
  text-decoration: none;
  border: none;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: var(--transition-base);
  outline: none;
}

.btn-primary {
  width: 100%;
  background: linear-gradient(135deg, var(--primary), var(--primary-hover));
  color: white;
  box-shadow: var(--shadow-lg);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
}

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

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

.btn-secondary:hover {
  background: var(--surface-light);
  transform: translateY(-2px);
}

.btn-sm {
  padding: var(--spacing-sm) var(--spacing-md);
  font-size: 0.875rem;
}

@media (max-width: 640px) {
  .btn-sm span {
    display: inline;
  }
}

/* ===================================
   Alerts
   =================================== */

.alert {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-lg);
  border-radius: var(--radius-lg);
  margin-bottom: var(--spacing-lg);
  font-size: 0.875rem;
  animation: slideDown 0.3s ease-out;
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.alert-error {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid var(--error);
  color: var(--error);
}

.alert i {
  font-size: 1.125rem;
}

.info-box {
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-sm);
  padding: var(--spacing-md);
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid var(--info);
  border-radius: var(--radius-lg);
  color: var(--info);
  font-size: 0.875rem;
  line-height: 1.5;
}

.info-box i {
  font-size: 1rem;
  margin-top: 2px;
  flex-shrink: 0;
}

/* ===================================
   Folder Grid
   =================================== */

.folder-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 350px));
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-2xl);
  justify-content: center;
  max-width: 1400px;
  margin-left: auto;
  margin-right: auto;
}

@media (max-width: 768px) {
  .folder-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }
}

.folder-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-lg);
  padding: var(--spacing-2xl);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-2xl);
  text-decoration: none;
  color: var(--text-primary);
  transition: var(--transition-base);
  position: relative;
  overflow: hidden;
  width: 100%;
  max-width: 350px;
  text-align: center;
}

.folder-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  opacity: 0;
  transition: var(--transition-base);
  z-index: 0;
}

.folder-card:hover::before {
  opacity: 0.05;
}

.folder-card:hover {
  border-color: var(--primary);
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.folder-card > * {
  position: relative;
  z-index: 1;
}

.folder-card-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100px;
  height: 100px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: var(--radius-2xl);
  flex-shrink: 0;
  box-shadow: var(--shadow-xl);
  margin-bottom: var(--spacing-md);
}

.folder-card-icon i {
  font-size: 3rem;
  color: white;
}



.folder-card-title {
  font-size: 1.375rem;
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
  width: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.folder-card-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xs);
  color: var(--text-muted);
  font-size: 0.875rem;
}

.folder-card-meta i {
  font-size: 0.75rem;
}

.folder-card-count {
  color: var(--primary-light);
  font-weight: 600;
}



/* ===================================
   File List
   =================================== */

.file-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-2xl);
}

.file-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  padding: var(--spacing-lg);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  text-decoration: none;
  color: var(--text-primary);
  transition: var(--transition-base);
  position: relative;
  overflow: hidden;
}

.file-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  opacity: 0;
  transition: var(--transition-base);
  z-index: 0;
}

.file-item:hover::before {
  opacity: 0.05;
}

.file-item:hover {
  border-color: var(--primary);
  transform: translateX(4px);
  box-shadow: var(--shadow-lg);
}

.file-item > * {
  position: relative;
  z-index: 1;
}

.file-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: var(--radius-lg);
  flex-shrink: 0;
  box-shadow: var(--shadow-md);
}

.file-icon i {
  font-size: 1.75rem;
  color: white;
}

.file-info {
  flex: 1;
  min-width: 0;
}

.file-name {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: var(--spacing-xs);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.file-meta {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  color: var(--text-muted);
  font-size: 0.875rem;
}

.file-meta span {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.file-meta i {
  font-size: 0.75rem;
}

.file-download {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: var(--radius-lg);
  color: white;
  transition: var(--transition-base);
  box-shadow: var(--shadow-md);
}

.file-download i {
  font-size: 1.5rem;
}

.file-item:hover .file-download {
  transform: scale(1.1);
  box-shadow: var(--shadow-lg);
}

@media (max-width: 640px) {
  .file-item {
    gap: var(--spacing-md);
    padding: var(--spacing-md);
  }
  
  .file-icon {
    width: 48px;
    height: 48px;
  }
  
  .file-icon i {
    font-size: 1.5rem;
  }
  
  .file-name {
    font-size: 1rem;
  }
  
  .file-meta {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--spacing-xs);
  }
}

/* ===================================
   Empty State
   =================================== */

.empty-state {
  text-align: center;
  padding: var(--spacing-3xl) var(--spacing-xl);
}

.empty-state-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 120px;
  height: 120px;
  background: var(--surface);
  border: 2px dashed var(--border);
  border-radius: var(--radius-2xl);
  margin-bottom: var(--spacing-xl);
}

.empty-state-icon i {
  font-size: 4rem;
  color: var(--text-muted);
  opacity: 0.5;
}

.empty-state-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
  color: var(--text-secondary);
}

.empty-state-text {
  color: var(--text-muted);
  font-size: 1rem;
  max-width: 500px;
  margin: 0 auto;
}

/* ===================================
   Back Button
   =================================== */

.download-all-container {
  display: flex;
  justify-content: center;
  margin-top: var(--spacing-xl);
  margin-bottom: var(--spacing-lg);
  opacity: 0.7;
  transition: var(--transition-base);
}

.download-all-container:hover {
  opacity: 1;
}

.download-all-container .btn {
  min-width: auto;
  font-size: 0.875rem;
  padding: var(--spacing-sm) var(--spacing-lg);
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-muted);
}

.download-all-container .btn:hover {
  border-color: var(--primary);
  color: var(--primary-light);
  background: rgba(79, 70, 229, 0.1);
  transform: none;
}

.back-button-container {
  display: flex;
  justify-content: center;
  margin-top: var(--spacing-2xl);
}

/* ===================================
   Footer
   =================================== */

.footer {
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: var(--spacing-xl) 0;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.875rem;
}

/* ===================================
   Animations
   =================================== */

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}