/* =========================================
   BIT DFS - Modern Minimalist Theme
   ========================================= */

:root {
  /* --- Color Palette (Light Mode Default) --- */
  --bg-body: #f8f9fa;
  --bg-sidebar: #ffffff;
  --bg-card: #ffffff;
  --bg-hover: #f1f3f5;
  --bg-active: #e9ecef;
  --row-bg: #ffffff;
  --row-hover-bg: #f8f9fa;
  
  --text-primary: #212529;
  --text-secondary: #6c757d;
  --text-muted: #adb5bd;
  
  --border-color: #dee2e6;
  --border-subtle: #f1f3f5;

  --primary-color: #42A5F5; /* Lighter blue */
  --primary-hover: #0b5ed7;
  --accent-color: #0dcaf0;
  --danger-color: #dc3545;
  --warning-color: #ffc107;
  
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.05);

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: 'JetBrains Mono', SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;

  /* Compatibility with progress.css */
  --text-main: var(--text-primary);
  --text-dim: var(--text-secondary);
  --accent-primary: var(--primary-color);
  --accent-secondary: var(--accent-color);
  --accent-danger: var(--danger-color);
  --btn-text-on-accent: #ffffff;

  --logo-shadow-color: rgba(0,0,0,0.8); /* Default for light mode */
}

/* --- Dark Mode Variables --- */
[data-theme="dark"] {
  --bg-body: #121212;
  --bg-sidebar: #1e1e1e;
  --bg-card: #1e1e1e;
  --bg-hover: #2c2c2c;
  --bg-active: #333333;
  --row-bg: #1e1e1e;
  --row-hover-bg: #2c2c2c;
  
  --text-primary: #e0e0e0;
  --text-secondary: #a0a0a0;
  --text-muted: #666666;
  
  --border-color: #333333;
  --border-subtle: #252525;
  
  --primary-color: #3b82f6;
  --primary-hover: #60a5fa;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.3);

  --logo-shadow-color: var(--border-color); /* Lighter shadow for dark mode */
}

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

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-body);
  color: var(--text-primary);
  height: 100vh;
  overflow: hidden; /* App-like feel */
  transition: background-color 0.3s ease, color 0.3s ease;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

a {
  text-decoration: none;
  color: inherit;
}

/* =========================================
   Layout Structure
   ========================================= */

.app-container {
  display: flex;
  height: 100vh;
  width: 100vw;
}

/* --- Sidebar --- */
.sidebar {
  width: 260px;
  background-color: var(--bg-sidebar);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  padding: 1.5rem 1.2rem;
  transition: width 0.3s ease;
  z-index: 10;
  backdrop-filter: blur(10px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 2.5rem;
  padding: 0.5rem 0.2rem;
}

.logo-icon {
  display: none; /* Hide default emoji icon */
}

.logo-text {
  font-family: 'Press Start 2P', cursive;
  font-size: 1.8rem;
  line-height: 1; /* Keep in one line */
  color: var(--accent-primary);
  /* Retro block shadow effect */
  text-shadow: 
    1px 1px 0px var(--logo-shadow-color),
    2px 2px 0px var(--logo-shadow-color),
    3px 3px 0px var(--logo-shadow-color),
    4px 4px 0px var(--logo-shadow-color),
    5px 5px 0px var(--logo-shadow-color),
    6px 6px 0px var(--logo-shadow-color);
  position: relative;
  letter-spacing: -2px;
  text-transform: uppercase;
  /* Removed padding: 5px 0; */
}

.nav-menu {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  flex: 1;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.85rem 1rem;
  border-radius: 8px;
  color: var(--text-secondary);
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  text-align: left;
  font-weight: 500;
  position: relative;
  overflow: hidden;
  cursor: pointer; /* Ensure cursor pointer */
}

.nav-item:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
  transform: translateX(4px);
}

.nav-item.active {
  background-color: rgba(var(--primary-rgb), 0.1); /* Fallback if var not defined, logic handled below */
  background-color: var(--bg-active);
  color: var(--primary-color);
  font-weight: 600;
  border-left: 3px solid var(--primary-color);
}

/* SVG Icons */
.svg-icon {
  width: 18px;
  height: 18px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.nav-item .svg-icon {
  width: 20px;
  height: 20px;
  opacity: 0.8;
}

.nav-item.active .svg-icon {
  opacity: 1;
  stroke: var(--primary-color);
}

.btn .svg-icon {
  width: 16px;
  height: 16px;
  margin-right: 4px;
}

.file-icon svg {
  width: 24px;
  height: 24px;
}


.sidebar-footer {
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid var(--border-subtle);
}

/* --- Storage Progress Bar --- */
.storage-status {
  margin-bottom: 1rem;
  padding: 0 0.5rem;
}

.storage-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.4rem;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.storage-usage {
  font-weight: 600;
  color: var(--text-primary);
}

.progress-bar-bg {
  width: 100%;
  height: 6px;
  background-color: var(--bg-active); /* Use active bg for track */
  border-radius: 3px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background-color: var(--primary-color);
  transition: width 0.5s ease;
  border-radius: 3px;
}

/* --- Theme Toggle (Day/Night Switch) --- */
.theme-toggle-wrapper {
  width: 100%;
  display: flex;
  justify-content: center;
  padding: 10px 0;
}

.toggle-wrapper {
  position: relative;
  overflow: hidden;
}

.toggle.checkcross {
    position: relative;
    display: inline-block;
}

.toggle.checkcross input {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
  z-index: 2;
}

.toggle.checkcross label.toggle-item {
  width: 80px;
  height: 34px;
  display: inline-block;
  background: url('assets/light-back.jpeg');
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
  border-radius: 50px;
  position: relative;
  border: 2px solid #fff;
  box-shadow: 0 0 5px rgba(0,0,0,0.2);
  transition: all 0.3s ease;
  cursor: pointer;
}

.toggle.checkcross .check {
  position: absolute;
  top: 2px;
  left: 2px;
  width: 26px;
  height: 26px;
  background: url('assets/light-dot.png');
  background-position: center;
  background-size: cover;
  background-repeat: no-repeat;
  transition: 0.4s ease;
  border-radius: 50%;
  box-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

/* Checked State (Dark Mode) */
.toggle.checkcross input:checked + label.toggle-item {
  background: url('assets/dark-back.jpeg');
  background-position: center;
  background-size: cover;
  background-repeat: no-repeat;
}

.toggle.checkcross input:checked + label .check {
  left: 48px; /* 80 - 26 - 2 - 4 (borders) */
  transform: rotate(360deg);
  background: url('assets/dark-dot.png');
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}

/* --- Main Content --- */
.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 0;
  overflow: hidden;
  position: relative;
}

.top-header {
  height: 64px;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background-color: var(--bg-body); /* Blends with body */
  flex-shrink: 0;
}

.breadcrumb-container {
  flex: 1;
}

.breadcrumb {
  display: flex;
  align-items: center;
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.breadcrumb a {
  color: var(--text-secondary);
  transition: color 0.2s;
  cursor: pointer;
}

.breadcrumb a:hover {
  color: var(--primary-color);
  text-decoration: underline;
}

.breadcrumb-sep {
  margin: 0 0.5rem;
  color: var(--text-muted);
}

.breadcrumb span:last-child {
  color: var(--text-primary);
  font-weight: 600;
}

/* --- Toolbar --- */
.toolbar {
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-shrink: 0;
}

.toolbar-left {
  display: flex;
  gap: 0.75rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.6rem 1.2rem;
  border-radius: 6px;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.2s ease;
  cursor: pointer;
}

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

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.btn-accent {
  background-color: var(--accent-color);
  color: #fff; /* Assuming white text for accent */
}

.btn-accent:hover {
  filter: brightness(0.9);
}

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

.btn-secondary:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--text-secondary);
}

.btn-select {
  background-color: rgba(66, 165, 245, 0.18);
  border: 1px solid rgba(66, 165, 245, 0.35);
  color: var(--primary-color);
}

.btn-select:hover {
  background-color: rgba(66, 165, 245, 0.28);
  color: var(--primary-hover);
  border-color: rgba(66, 165, 245, 0.5);
}

[data-theme="dark"] .btn-select {
  background-color: rgba(59, 130, 246, 0.22);
  border: 1px solid rgba(147, 197, 253, 0.45);
  color: #9ec7ff;
}

[data-theme="dark"] .btn-select:hover {
  background-color: rgba(59, 130, 246, 0.32);
  color: #c8e0ff;
  border-color: rgba(147, 197, 253, 0.6);
}

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

.btn-danger:hover {
  filter: brightness(0.9);
}

.btn-icon {
  padding: 0.4rem;
  border-radius: 4px;
  color: var(--text-secondary);
  cursor: pointer;
}

.btn-icon:hover {
  background-color: var(--bg-hover);
  color: var(--text-primary);
}

/* --- File List --- */
.file-list-wrapper {
  flex: 1;
  overflow-y: auto;
  padding: 0 2rem 2rem 2rem;
  position: relative;
}

.file-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
}

.file-table th {
  text-align: left;
  padding: 1rem;
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.85rem;
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  background-color: var(--bg-body);
  z-index: 5;
}

.file-table td {
  padding: 0.8rem 1rem;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  vertical-align: middle;
  transition: background 0.1s;
  background-color: var(--row-bg); /* Restore row background */
}

.file-table tr {
  transition: background-color 0.1s ease;
}

.file-table tr:hover td {
  background-color: var(--row-hover-bg); /* Restore hover background */
}

.file-name {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--text-primary) !important;
  font-weight: 500;
}

.folder-link:hover {
  text-decoration: underline;
  color: var(--primary-color) !important;
}

.file-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  margin-right: 8px;
  color: var(--text-secondary);
}

.file-icon.folder {
  color: var(--folder-color);
  fill: currentColor;
}

.file-icon.file {
  color: var(--text-secondary);
}

/* Action icons appear on hover */
.action-icons {
  display: inline-flex;
  gap: 0.5rem;
  margin-left: auto;
  opacity: 0;
  transition: opacity 0.2s;
  align-items: center;
}

.file-table tr:hover .action-icons {
  opacity: 1;
}

.icon-btn {
  padding: 6px;
  border-radius: 4px;
  color: var(--text-secondary);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  background: transparent;
}

.icon-btn:hover {
  background-color: var(--bg-hover);
  color: var(--primary-color);
  border-color: var(--border-subtle);
  box-shadow: var(--shadow-sm);
}

.icon-btn .svg-icon {
  width: 16px;
  height: 16px;
  stroke-width: 2;
}

/* Empty State */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 4rem 0;
  color: var(--text-muted);
}

.empty-icon {
  font-size: 4rem;
  margin-bottom: 1rem;
  opacity: 0.5;
}

/* --- Preview Sidebar --- */
.preview-sidebar {
  width: 320px;
  background-color: var(--bg-card);
  border-left: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  box-shadow: -2px 0 10px rgba(0,0,0,0.02);
  z-index: 20;
  
  position: fixed;
  top: 0;
  right: 0;
  height: 100%;
  transform: translateX(100%);
  transition: transform 0.3s ease-in-out;
}

.preview-sidebar.is-open {
  transform: translateX(0);
}

.preview-header {
  padding: 1rem;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.preview-content {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.preview-placeholder {
  text-align: center;
  color: var(--text-muted);
  margin-top: 40%;
}

.placeholder-icon {
  font-size: 3rem;
  margin-bottom: 0.5rem;
}

.preview-media img {
  max-width: 100%;
  border-radius: 8px;
  box-shadow: var(--shadow-md);
}

.preview-pdf {
  width: 100%;
  flex: 1;
  align-self: stretch;
}

.preview-pdf iframe {
  width: 100%;
  height: 70vh;
  border: none;
  border-radius: 8px;
  background: var(--bg-body);
}

.preview-code {
  width: 100%;
  background: var(--bg-active);
  padding: 1rem;
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  overflow-x: auto;
  color: var(--text-primary);
  white-space: pre-wrap;
}

.preview-footer {
  padding: 1rem;
  border-top: 1px solid var(--border-color);
  text-align: center;
}

/* Make load more wrapper larger and ensure clicks reach the button */
.preview-loadmore-wrap {
  display: inline-block;
  padding: 6px; /* expand hit area */
  border-radius: 8px;
  cursor: pointer;
  position: relative;
  z-index: 40; /* sit above potential overlays */
}

.preview-loadmore-wrap .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.45rem 0.9rem;
  pointer-events: auto; /* ensure button receives events */
}

/* If an overlay covers the footer, allow wrapper to forward click to button */
.preview-footer { position: relative; z-index: 30; }

/* =========================================
   Modals (Modern Dialogs)
   ========================================= */

.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0,0,0,0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  backdrop-filter: blur(2px);
  animation: fadeIn 0.2s ease-out;
}

.modal-card {
  background-color: var(--bg-card);
  width: 500px;
  max-width: 90%;
  border-radius: 12px;
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  animation: slideUp 0.2s ease-out;
}

.modal-card.small {
  width: 350px;
}

.modal-header {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.modal-header h2 {
  font-size: 1.1rem;
  font-weight: 600;
}

.modal-header.warning {
  background-color: #fff3cd;
  color: #856404;
}

.modal-body {
  padding: 1.5rem;
  flex: 1;
}

.modal-footer {
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  background-color: var(--bg-body);
}

.form-group {
  margin-bottom: 1rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.form-control {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  background-color: var(--bg-body);
  color: var(--text-primary);
  font-family: inherit;
  transition: border-color 0.2s;
}

.form-control:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(13, 110, 253, 0.1);
}

/* Dropdown in Modal */
.path-selector {
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 0.75rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  background-color: var(--bg-body);
}

.dropdown-list {
  margin-top: 0.5rem;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  max-height: 150px;
  overflow-y: auto;
  background-color: var(--bg-card);
}

.dropdown-list div {
  padding: 0.5rem 0.75rem;
  cursor: pointer;
}

.dropdown-list div:hover {
  background-color: var(--bg-hover);
}

/* Utilities */
.hidden {
  display: none !important;
}

.spacer {
  flex: 1;
}

.text-center { text-align: center; }
.text-muted { color: var(--text-muted); }
.mt-4 { margin-top: 1.5rem; }

/* Spinner */
.spinner {
  width: 24px;
  height: 24px;
  border: 3px solid var(--border-subtle);
  border-top-color: var(--primary-color);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.spinner-large {
  width: 40px;
  height: 40px;
  border-width: 4px;
  border-top-color: var(--danger-color);
  margin: 0 auto;
}

/* Upload area: place pick button and status on one line */
.upload-area {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.upload-area .btn.btn-block {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: auto; /* override any full-width utility */
  padding: 0.45rem 0.9rem;
}

.upload-area .file-status,
.file-status {
  color: var(--text-secondary);
  font-size: 0.95rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 60%;
}

@media (max-width: 520px) {
  .upload-area {
    flex-direction: column;
    align-items: stretch;
    gap: 0.5rem;
  }
  .upload-area .file-status { max-width: 100%; }
}

/* "Up" row (返回上一级) should not receive hover background like normal rows */
.file-table tr.up-row td {
  background-color: transparent;
}
.file-table tr.up-row:hover td {
  background-color: transparent;
}
.file-table tr.up-row td.placeholder {
  color: var(--text-muted);
}

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

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

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

/* User Center Styles */
.user-info-section {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: 1.5rem;
  background: linear-gradient(135deg, var(--primary-color) 0%, #4a9eff 100%);
  border-radius: 12px;
  margin-bottom: 1.5rem;
}

.user-avatar {
  font-size: 3rem;
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: rgba(255, 255, 255, 0.2);
  border-radius: 50%;
}

.user-details {
  flex: 1;
}

.user-id-label {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.8);
  margin: 0 0 0.25rem 0;
}

.user-id-value {
  font-size: 1.25rem;
  font-weight: 600;
  color: #fff;
  margin: 0;
}

.user-actions {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

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

.btn-danger {
  background-color: #dc3545;
  color: #fff;
  border: none;
}

.btn-danger:hover {
  background-color: #bb2d3b;
}

/* Progress Container */
.progress-container-wrapper {
  position: fixed;
  bottom: 20px;
  right: 20px;
  width: 300px;
  z-index: 50;
  display: flex;
  flex-direction: column;
  gap: 10px;
}