/* =====================
   CSS VARIABLES — THEMES
===================== */

:root,
[data-theme="dark"] {
  --bg:           #0d0f14;
  --panel:        rgba(18, 22, 30, 0.80);
  --panel-solid:  #12161e;
  --panel-hover:  rgba(255,255,255,0.04);
  --text:         #dde1e8;
  --muted:        #7a8494;
  --border:       rgba(255,255,255,0.07);
  --border-hover: rgba(255,255,255,0.14);
  --accent:       var(--user-accent, #7dd3fc);
  --accent-dim:   rgba(125,211,252,0.10);
  --danger:       #f87171;
  --input-bg:     rgba(10,12,18,0.7);
  --shadow:       0 8px 40px rgba(0,0,0,0.55);
  --shadow-sm:    0 2px 8px rgba(0,0,0,0.3);
  --blur:         blur(16px);
  --sidebar-w:    260px;
  --header-h:     48px;
  --radius:       8px;
  --radius-sm:    5px;
  --transition:   0.18s ease;
}

[data-theme="light"] {
  --bg:           #eef0f4;
  --panel:        rgba(255,255,255,0.78);
  --panel-solid:  #ffffff;
  --panel-hover:  rgba(0,0,0,0.03);
  --text:         #1c1f26;
  --muted:        #6b7280;
  --border:       rgba(0,0,0,0.09);
  --border-hover: rgba(0,0,0,0.16);
  --accent:       var(--user-accent, #0284c7);
  --accent-dim:   rgba(2,132,199,0.10);
  --danger:       #dc2626;
  --input-bg:     rgba(255,255,255,0.85);
  --shadow:       0 8px 40px rgba(0,0,0,0.12);
  --shadow-sm:    0 2px 8px rgba(0,0,0,0.06);
  --blur:         blur(16px);
}

/* =====================
   RESET
===================== */

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

body {
  font-family: ui-monospace, 'Cascadia Code', SFMono-Regular, Menlo, monospace;
  color: var(--text);
  min-height: 100vh;
  transition: color var(--transition), background-color var(--transition);
  overflow: hidden;
}

/* =====================
   BACKGROUND
===================== */

.bg-layer {
  position: fixed;
  inset: 0;
  z-index: -1;
  background-color: var(--bg);
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
  transition: background-color var(--transition);
}

/* =====================
   SCROLLBARS
===================== */

::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-hover); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--muted); }

/* =====================
   LOGIN PAGE
===================== */

.login-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.login-box {
  background: var(--panel);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 44px 48px;
  width: 100%;
  max-width: 380px;
  box-shadow: var(--shadow);
  animation: fadeUp 0.35s ease;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

.login-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 32px;
}

.login-logo h1 {
  font-size: 20px;
  color: var(--accent);
  letter-spacing: 0.5px;
}

.input-group {
  margin-bottom: 16px;
}

.input-group label {
  display: block;
  font-size: 11px;
  color: var(--muted);
  letter-spacing: 0.8px;
  text-transform: uppercase;
  margin-bottom: 6px;
}

.input-group input {
  display: block;
  width: 100%;
  background: var(--input-bg);
  backdrop-filter: var(--blur);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 10px 13px;
  font-family: inherit;
  font-size: 14px;
  border-radius: var(--radius-sm);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.input-group input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-dim);
}

.login-btn {
  width: 100%;
  margin-top: 8px;
  padding: 11px 16px;
  background: var(--accent-dim);
  border: 1px solid var(--accent);
  color: var(--accent);
  cursor: pointer;
  font-family: inherit;
  font-size: 14px;
  border-radius: var(--radius-sm);
  letter-spacing: 0.3px;
  transition: background var(--transition), color var(--transition), transform 0.1s;
}

.login-btn:hover {
  background: var(--accent);
  color: #000;
}

.login-btn:active { transform: scale(0.98); }

/* =====================
   APP LAYOUT
===================== */

.app-container {
  display: flex;
  height: 100vh;
  overflow: hidden;
  transition: none;
}

/* =====================
   SIDEBAR
===================== */

.sidebar {
  width: var(--sidebar-w);
  min-width: 180px;
  max-width: 420px;
  flex-shrink: 0;
  background: var(--panel);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transition: width 0.25s ease, transform 0.3s ease;
  z-index: 100;
}

/* Collapsed desktop sidebar */
.app-container.sidebar-collapsed .sidebar {
  width: 0 !important;
  min-width: 0;
  border-right: none;
  overflow: hidden;
}

.app-container.sidebar-collapsed .resize-handle {
  display: none;
}

.sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 14px 0;
  flex-shrink: 0;
}

.sidebar-title-row {
  display: flex;
  align-items: center;
  gap: 7px;
}

.sidebar-title {
  font-size: 11px;
  color: var(--muted);
  letter-spacing: 1.5px;
  text-transform: uppercase;
  white-space: nowrap;
}

.sidebar-controls {
  display: flex;
  align-items: center;
  gap: 4px;
}

/* Sidebar search */
.sidebar-search {
  padding: 10px 14px 6px;
  flex-shrink: 0;
}

.sidebar-search input {
  width: 100%;
  background: var(--input-bg);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 6px 10px;
  font-family: inherit;
  font-size: 12px;
  border-radius: var(--radius-sm);
  outline: none;
  transition: border-color var(--transition);
}

.sidebar-search input:focus { border-color: var(--accent); }
.sidebar-search input::placeholder { color: var(--muted); }

/* =====================
   FILE TREE
===================== */

.file-tree {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 6px 8px;
}

/* Folder toggle button */
.folder-toggle {
  display: flex;
  align-items: center;
  gap: 5px;
  width: 100%;
  background: none;
  border: none;
  color: var(--muted);
  font-family: inherit;
  font-size: 13px;
  padding: 5px 8px;
  padding-left: 8px; /* overridden per-depth by JS */
  cursor: pointer;
  border-radius: var(--radius-sm);
  text-align: left;
  transition: background var(--transition), color var(--transition);
  margin-top: 2px;
}

.folder-toggle:hover {
  background: var(--panel-hover);
  color: var(--text);
}

.folder-arrow {
  font-size: 10px;
  color: var(--muted);
  transition: transform 0.2s ease;
  display: inline-block;
  width: 12px;
  flex-shrink: 0;
}

.folder-icon { flex-shrink: 0; }

.folder-name {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* Folder children container */
.folder-children {
  /* no padding here — JS handles per-file indentation */
}

/* File link */
a.tree-file {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px 8px;
  padding-left: 8px; /* overridden by JS */
  color: var(--text);
  text-decoration: none;
  font-size: 13px;
  border-radius: var(--radius-sm);
  transition: background var(--transition), color var(--transition);
  white-space: nowrap;
  overflow: hidden;
}

a.tree-file:hover {
  background: var(--panel-hover);
  color: var(--accent);
}

a.tree-file.active {
  background: var(--accent-dim);
  color: var(--accent);
  font-weight: 500;
}

.file-icon, .folder-icon { flex-shrink: 0; font-size: 12px; }

.file-name {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  flex: 1;
}

/* =====================
   SIDEBAR BOTTOM
===================== */

.sidebar-bottom {
  margin-top: auto;
  padding: 12px 12px 14px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex-shrink: 0;
}

.logout-link {
  display: block;
  font-size: 12px;
  color: var(--muted);
  text-decoration: none;
  padding: 5px 6px;
  border-radius: var(--radius-sm);
  transition: color var(--transition), background var(--transition);
}

.logout-link:hover {
  color: var(--danger);
  background: rgba(248,113,113,0.07);
}

/* =====================
   RESIZE HANDLE
===================== */

.resize-handle {
  width: 4px;
  flex-shrink: 0;
  cursor: col-resize;
  background: transparent;
  transition: background 0.15s;
  position: relative;
  z-index: 10;
}

.resize-handle:hover,
.resize-handle:active {
  background: var(--accent);
  opacity: 0.5;
}

/* =====================
   ICON BUTTONS
===================== */

.icon-btn {
  background: none;
  border: 1px solid var(--border);
  color: var(--muted);
  cursor: pointer;
  font-size: 13px;
  padding: 4px 7px;
  border-radius: var(--radius-sm);
  line-height: 1;
  transition: border-color var(--transition), color var(--transition), background var(--transition);
  white-space: nowrap;
}

.icon-btn:hover {
  border-color: var(--border-hover);
  color: var(--accent);
  background: var(--accent-dim);
}

/* =====================
   MAIN CONTENT
===================== */

.main {
  flex: 1;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

/* =====================
   NOTE HEADER
===================== */

.note-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 20px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  flex-shrink: 0;
  min-height: var(--header-h);
  gap: 12px;
}

.note-breadcrumb {
  flex: 1;
  overflow: hidden;
}

.breadcrumb-path {
  font-size: 13px;
  color: var(--muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  display: block;
}

/* Highlight filename portion */
.breadcrumb-path::after { content: ''; }

.note-header-actions {
  display: flex;
  gap: 6px;
  flex-shrink: 0;
}

/* =====================
   SPLIT VIEW
===================== */

.split {
  display: flex;
  flex: 1;
  overflow: hidden;
  gap: 0;
}

/* View mode overrides */
.split[data-view="editor"] .split-preview { display: none; }
.split[data-view="preview"] .split-editor { display: none; }
.split[data-view="editor"] .split-editor,
.split[data-view="preview"] .split-preview { flex: 1; }

/* Editor pane */
.split-editor {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border-right: 1px solid var(--border);
  min-width: 0;
}

.editor-form {
  display: flex;
  flex-direction: column;
  flex: 1;
  overflow: hidden;
}

textarea {
  flex: 1;
  width: 100%;
  background: var(--panel);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  border: none;
  color: var(--text);
  padding: 20px 24px;
  font-family: inherit;
  font-size: 13px;
  line-height: 1.75;
  resize: none;
  outline: none;
  transition: background var(--transition);
  overflow-y: auto;
}

textarea::placeholder { color: var(--muted); opacity: 0.6; }

textarea:focus {
  background: rgba(255,255,255,0.015);
}

[data-theme="light"] textarea:focus {
  background: rgba(0,0,0,0.01);
}

/* Editor footer */
.editor-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 14px;
  border-top: 1px solid var(--border);
  background: var(--panel);
  flex-shrink: 0;
  gap: 12px;
  flex-wrap: wrap;
}

.editor-stats {
  font-size: 11px;
  color: var(--muted);
  white-space: nowrap;
}

.editor-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.shortcut-hint {
  font-size: 11px;
  color: var(--muted);
  opacity: 0.6;
}

/* Preview pane */
.split-preview {
  flex: 1;
  overflow-y: auto;
  min-width: 0;
}

.preview-content {
  padding: 24px 28px;
  max-width: 780px;
}

/* =====================
   MARKDOWN PREVIEW STYLES
===================== */

.preview-content h1,
.preview-content h2,
.preview-content h3,
.preview-content h4,
.preview-content h5,
.preview-content h6 {
  color: var(--accent);
  margin: 20px 0 8px;
  line-height: 1.3;
}

.preview-content h1 { font-size: 22px; border-bottom: 1px solid var(--border); padding-bottom: 6px; }
.preview-content h2 { font-size: 18px; }
.preview-content h3 { font-size: 15px; }
.preview-content h4 { font-size: 14px; color: var(--text); }

.preview-content p  { line-height: 1.8; margin-bottom: 14px; font-size: 14px; }
.preview-content ul,
.preview-content ol { padding-left: 22px; margin-bottom: 14px; font-size: 14px; line-height: 1.75; }
.preview-content li { margin-bottom: 4px; }

.preview-content code {
  background: var(--accent-dim);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 12.5px;
}

.preview-content pre {
  background: rgba(0,0,0,0.22);
  padding: 16px 18px;
  overflow-x: auto;
  border-radius: var(--radius);
  margin-bottom: 16px;
  border: 1px solid var(--border);
}

[data-theme="light"] .preview-content pre {
  background: rgba(0,0,0,0.05);
}

.preview-content pre code { background: none; padding: 0; font-size: 13px; }

.preview-content a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; }
.preview-content a:hover { opacity: 0.8; }

.preview-content blockquote {
  border-left: 3px solid var(--accent);
  padding: 8px 16px;
  color: var(--muted);
  margin: 14px 0;
  font-style: italic;
  background: var(--accent-dim);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.preview-content hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 24px 0;
}

.preview-content img { max-width: 100%; border-radius: var(--radius-sm); margin: 8px 0; }

.preview-content del { opacity: 0.5; text-decoration: line-through; }

.preview-content table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 16px;
  font-size: 13px;
}

.preview-content th,
.preview-content td {
  padding: 8px 12px;
  border: 1px solid var(--border);
  text-align: left;
}

.preview-content th {
  background: var(--accent-dim);
  color: var(--accent);
  font-weight: 600;
}

.preview-content tr:nth-child(even) td {
  background: var(--panel-hover);
}

/* =====================
   WELCOME SCREEN
===================== */

.welcome {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 40px 24px;
  gap: 12px;
}

.welcome-icon { opacity: 0.4; margin-bottom: 8px; }
.welcome h1 { color: var(--accent); font-size: 22px; }
.welcome p  { color: var(--muted); font-size: 14px; }
.welcome-hint { font-size: 12px; opacity: 0.6; }

/* =====================
   BUTTONS
===================== */

button, .btn {
  background: transparent;
  border: 1px solid var(--accent);
  color: var(--accent);
  padding: 6px 14px;
  cursor: pointer;
  font-family: inherit;
  font-size: 13px;
  border-radius: var(--radius-sm);
  transition: background var(--transition), color var(--transition), transform 0.1s;
  text-decoration: none;
  display: inline-block;
  white-space: nowrap;
}

button:hover, .btn:hover {
  background: var(--accent);
  color: #000;
}

button:active, .btn:active { transform: scale(0.97); }

button.danger {
  border-color: var(--danger);
  color: var(--danger);
}

button.danger:hover {
  background: var(--danger);
  color: #fff;
}

.save-btn {
  background: var(--accent-dim);
}

/* =====================
   NEW NOTE FORM
===================== */

.new-note-form {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.new-note-form input {
  width: 100%;
  background: var(--input-bg);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 6px 10px;
  font-family: inherit;
  font-size: 12px;
  border-radius: var(--radius-sm);
  outline: none;
  transition: border-color var(--transition);
}

.new-note-form input:focus { border-color: var(--accent); }
.new-note-form input::placeholder { color: var(--muted); opacity: 0.7; }
.new-note-btn { width: 100%; font-size: 12px; padding: 6px 10px; }

/* =====================
   HAMBURGER (mobile)
===================== */

.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  background: var(--panel);
  backdrop-filter: var(--blur);
  border: 1px solid var(--border);
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 200;
  width: 38px;
  height: 38px;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition);
}

.hamburger span {
  display: block;
  width: 16px;
  height: 1.5px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.hamburger.active span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.hamburger.active span:nth-child(2) { opacity: 0; transform: scaleX(0); }
.hamburger.active span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.55);
  z-index: 99;
  backdrop-filter: blur(2px);
}

/* =====================
   RESPONSIVE — TABLET (≤900px)
===================== */

@media (max-width: 900px) {
  :root { --sidebar-w: 240px; }
  .shortcut-hint { display: none; }
}

/* =====================
   RESPONSIVE — MOBILE (≤768px)
===================== */

@media (max-width: 768px) {
  body { overflow: auto; }

  .hamburger { display: flex; }

  .sidebar {
    position: fixed;
    top: 0; left: 0; bottom: 0;
    transform: translateX(-100%);
    width: 280px !important;
    max-width: 85vw;
    box-shadow: none;
    overflow-y: auto;
  }

  .sidebar.open {
    transform: translateX(0);
    box-shadow: 4px 0 40px rgba(0,0,0,0.45);
  }

  .sidebar-overlay.open { display: block; }

  .app-container { display: block; height: auto; overflow: auto; }

  .resize-handle { display: none; }

  .sidebar-collapse-btn { display: none; }

  .main {
    padding-top: 58px;
    min-height: 100vh;
    overflow: auto;
  }

  .split {
    flex-direction: column;
    height: auto;
    overflow: visible;
  }

  .split-editor {
    border-right: none;
    border-bottom: 1px solid var(--border);
    min-height: 300px;
  }

  textarea {
    min-height: 260px;
    overflow-y: auto;
    flex: none;
  }

  .split-preview { min-height: 280px; }

  .note-header { padding: 10px 14px 10px 56px; }

  .editor-footer { padding: 8px 12px; }

  .login-box { padding: 32px 26px; }
}

/* =====================
   RESPONSIVE — SMALL MOBILE (≤480px)
===================== */

@media (max-width: 480px) {
  .editor-actions { flex-direction: column; align-items: stretch; }
  .editor-actions button { width: 100%; text-align: center; }
  .editor-footer { flex-direction: column; align-items: flex-start; gap: 8px; }
  .preview-content { padding: 16px; }
}