*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; overflow: hidden; background: #f5f5f7; color: #1d1d1f; font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif; font-size: 13px; user-select: none; -webkit-font-smoothing: antialiased; }

:root {
  --bg:      #f5f5f7;
  --panel:   #ffffff;
  --panel2:  #f5f5f7;
  --panel3:  #fafafa;
  --accent:  #0071e3;
  --text:    #1d1d1f;
  --text2:   #6e6e73;
  --text3:   #aeaeb2;
  --border:  #d2d2d7;
  --border2: #e5e5ea;
  --hover:   #f0f0f5;
  --sel:     rgba(0,113,227,.09);
  --red:     #ff3b30;
  --green:   #34c759;
  --orange:  #ff9500;
  --topbar:  44px;
  --lbar:    50px;
  --rbar:    262px;
  --sbar:    22px;
  --tline:   116px;
}

/* ── LAYOUT ────────────────────────────────────────── */
#app { display: grid; grid-template-rows: var(--topbar) 1fr var(--sbar); height: 100vh; width: 100vw; }
#topbar {
  display: flex; align-items: center; background: rgba(255,255,255,.92);
  backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border); padding: 0 8px; gap: 2px; z-index: 200;
}
#workspace { display: grid; grid-template-columns: var(--lbar) 1fr var(--rbar); overflow: hidden; }
#statusbar {
  background: var(--panel); border-top: 1px solid var(--border);
  display: flex; align-items: center; padding: 0 12px; gap: 20px;
  font-size: 11px; color: var(--text3);
}

/* ── TOPBAR ─────────────────────────────────────────── */
.tb-brand { font-size: 14px; font-weight: 700; color: var(--text); letter-spacing: -.02em; padding: 0 8px; }
.tb-brand span { color: var(--accent); }
.tb-sep { width: 1px; height: 22px; background: var(--border); margin: 0 2px; }

.menu-btn, .tb-btn, .view-btn {
  padding: 4px 10px; border: none; border-radius: 6px; background: transparent;
  color: var(--text2); font-size: 12px; cursor: pointer; transition: all .12s; font-family: inherit;
}
.menu-btn:hover, .tb-btn:hover, .view-btn:hover { background: var(--hover); color: var(--text); }

.mode-btn {
  padding: 5px 14px; border: none; border-radius: 980px; background: transparent;
  color: var(--text2); font-size: 12px; font-weight: 500; cursor: pointer; transition: all .15s; font-family: inherit;
}
.mode-btn.active { background: var(--accent); color: #fff; }
.mode-btn:hover:not(.active) { background: var(--hover); color: var(--text); }

.tb-right { margin-left: auto; display: flex; align-items: center; gap: 8px; }
#btn-save {
  padding: 5px 14px; background: var(--accent); border: none; border-radius: 980px;
  color: #fff; font-size: 12px; font-weight: 500; cursor: pointer; font-family: inherit; transition: background .15s;
}
#btn-save:hover { background: #0064cc; }
.tb-user { color: var(--text3); font-size: 12px; }
#btn-home {
  padding: 5px 10px; background: transparent; border: 1px solid var(--border);
  border-radius: 980px; color: var(--text2); font-size: 11px; cursor: pointer; font-family: inherit; transition: all .15s;
}
#btn-home:hover { border-color: var(--text); color: var(--text); }
.save-indicator { font-size: 11px; color: var(--text3); }
.save-indicator.saving { color: var(--orange); }
.save-indicator.saved  { color: var(--green); }

/* ── DROPDOWN MENUS ─────────────────────────────────── */
.menu-group { position: relative; }
.dropdown {
  position: absolute; top: calc(100% + 4px); left: 0;
  background: rgba(255,255,255,.97); border: 1px solid var(--border);
  border-radius: 10px; min-width: 200px; z-index: 500; padding: 4px;
  box-shadow: 0 8px 32px rgba(0,0,0,.12); display: none;
  backdrop-filter: blur(20px);
}
.dropdown.open { display: block; }
.dropdown hr { border: none; border-top: 1px solid var(--border2); margin: 3px 0; }
.dd-item {
  display: flex; align-items: center; gap: 8px; padding: 6px 10px;
  border-radius: 6px; cursor: pointer; transition: background .1s;
  font-size: 12px; color: var(--text);
}
.dd-item:hover { background: var(--sel); }
.dd-item .shortcut { margin-left: auto; color: var(--text3); font-size: 11px; }
.dd-item.danger { color: var(--red); }
.dd-item.danger:hover { background: rgba(255,59,48,.06); }

/* ── LEFT TOOLBAR ────────────────────────────────────── */
#left-panel {
  background: var(--panel); border-right: 1px solid var(--border);
  display: flex; flex-direction: column; align-items: center;
  padding: 8px 0; gap: 1px; overflow-y: auto;
}
.tool-btn {
  width: 38px; height: 38px; border: none; border-radius: 8px;
  background: transparent; color: var(--text2); cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  font-size: 15px; transition: all .12s; position: relative;
}
.tool-btn:hover { background: var(--hover); color: var(--text); }
.tool-btn.active { background: rgba(0,113,227,.1); color: var(--accent); }
.tool-sep { width: 22px; height: 1px; background: var(--border2); margin: 3px auto; }

.tool-btn::after {
  content: attr(data-tip); position: absolute; left: 44px; top: 50%;
  transform: translateY(-50%); background: var(--text); color: #fff;
  font-size: 11px; white-space: nowrap; padding: 4px 8px; border-radius: 6px;
  pointer-events: none; opacity: 0; transition: opacity .15s; z-index: 300;
}
.tool-btn:hover::after { opacity: 1; }

/* ── VIEWPORT ─────────────────────────────────────────── */
#viewport-container { position: relative; overflow: hidden; background: #e8e8ed; }
#viewport-2d, #viewport-3d { position: absolute; inset: 0; }
#viewport-3d { display: none; }
#canvas-2d { display: block; cursor: crosshair; }
#canvas-3d { display: block; }

.view-buttons {
  position: absolute; top: 10px; left: 10px; display: flex; flex-direction: column; gap: 3px; z-index: 10;
}
.vb {
  padding: 4px 10px; background: rgba(255,255,255,.9); border: 1px solid var(--border);
  border-radius: 6px; color: var(--text2); font-size: 11px; cursor: pointer;
  font-family: inherit; transition: all .12s; backdrop-filter: blur(8px);
}
.vb:hover { color: var(--accent); border-color: var(--accent); }

#sketch-info {
  position: absolute; bottom: 8px; left: 8px;
  background: rgba(255,255,255,.9); border: 1px solid var(--border);
  border-radius: 8px; padding: 6px 12px; font-size: 11px; color: var(--text2);
  pointer-events: none; z-index: 10; backdrop-filter: blur(8px);
}

/* ── RIGHT PANEL ──────────────────────────────────────── */
#right-panel { background: var(--panel); border-left: 1px solid var(--border); display: flex; flex-direction: column; overflow: hidden; }
.rp-tabs { display: flex; border-bottom: 1px solid var(--border); background: var(--panel2); }
.rp-tab {
  flex: 1; padding: 8px 4px; border: none; background: transparent;
  color: var(--text3); font-size: 11px; cursor: pointer;
  border-bottom: 2px solid transparent; transition: all .12s; font-family: inherit;
}
.rp-tab.active { color: var(--accent); border-bottom-color: var(--accent); background: var(--panel); }
.rp-tab:hover:not(.active) { color: var(--text2); }
.rp-content { flex: 1; overflow-y: auto; padding: 10px; display: none; }
.rp-content.active { display: block; }

/* Feature Tree */
.tree-row {
  display: flex; align-items: center; gap: 4px; padding: 3px 6px;
  border-radius: 6px; cursor: pointer; transition: background .1s;
}
.tree-row:hover { background: var(--hover); }
.tree-row.selected { background: var(--sel); }
.tree-toggle { width: 14px; font-size: 10px; color: var(--text3); text-align: center; cursor: pointer; }
.tree-icon { font-size: 12px; }
.tree-label { flex: 1; font-size: 12px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.tree-vis { font-size: 11px; color: var(--text3); cursor: pointer; }
.tree-vis:hover { color: var(--text); }
.tree-children { padding-left: 14px; }
.tree-children.collapsed { display: none; }

/* Properties */
.prop-section { margin-bottom: 14px; }
.prop-title { font-size: 10px; color: var(--text3); text-transform: uppercase; letter-spacing: .06em; margin-bottom: 6px; font-weight: 500; }
.prop-row { display: flex; align-items: center; gap: 8px; margin-bottom: 5px; }
.prop-label { width: 60px; color: var(--text2); font-size: 11px; }
.prop-input {
  flex: 1; background: var(--panel2); border: 1px solid var(--border);
  border-radius: 6px; color: var(--text); font-size: 11px; padding: 4px 7px;
  font-family: inherit; outline: none;
}
.prop-input:focus { border-color: var(--accent); box-shadow: 0 0 0 2px rgba(0,113,227,.1); }
.prop-btn {
  width: 100%; padding: 7px; background: var(--panel2); border: 1px solid var(--border);
  border-radius: 8px; color: var(--text); font-size: 11px; cursor: pointer;
  margin-top: 4px; transition: all .12s; font-family: inherit;
}
.prop-btn:hover { border-color: var(--accent); color: var(--accent); background: rgba(0,113,227,.04); }
.prop-btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.prop-btn.primary:hover { background: #0064cc; }

.color-row { display: flex; flex-wrap: wrap; gap: 5px; padding: 4px 0; }
.color-swatch {
  width: 22px; height: 22px; border-radius: 6px; cursor: pointer;
  border: 2px solid transparent; transition: all .12s;
}
.color-swatch:hover, .color-swatch.active { border-color: var(--text); transform: scale(1.1); }

/* ── TIMELINE (4D) ────────────────────────────────────── */
#timeline-bar {
  height: var(--tline); background: var(--panel); border-top: 1px solid var(--border);
  display: none; flex-direction: column;
}
#timeline-bar.visible { display: flex; }
#timeline-controls {
  display: flex; align-items: center; gap: 6px; padding: 4px 10px;
  border-bottom: 1px solid var(--border2); height: 32px;
}
.tl-btn {
  width: 24px; height: 24px; border: none; background: transparent;
  color: var(--text2); font-size: 13px; cursor: pointer; border-radius: 5px; transition: all .12s; font-family: inherit;
}
.tl-btn:hover { background: var(--hover); color: var(--text); }
.tl-btn.active { color: var(--accent); }
#timeline-time { font-size: 11px; color: var(--text2); min-width: 60px; text-align: center; font-variant-numeric: tabular-nums; }
.tl-sep { width: 1px; height: 16px; background: var(--border2); }
#timeline-tracks { flex: 1; overflow: hidden; display: flex; }
#track-labels { width: 120px; border-right: 1px solid var(--border2); overflow-y: auto; }
.track-label {
  height: 22px; display: flex; align-items: center; padding: 0 8px;
  font-size: 11px; color: var(--text2); border-bottom: 1px solid var(--border2);
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
#track-area { flex: 1; overflow: hidden; position: relative; }
#track-canvas { display: block; }

/* ── CONTEXT MENU ──────────────────────────────────────── */
#context-menu {
  position: fixed; background: rgba(255,255,255,.97); border: 1px solid var(--border);
  border-radius: 10px; padding: 4px; min-width: 160px; z-index: 1000;
  box-shadow: 0 8px 32px rgba(0,0,0,.12); display: none;
  backdrop-filter: blur(20px);
}
#context-menu.open { display: block; }
.cm-item {
  padding: 6px 12px; border-radius: 6px; cursor: pointer; font-size: 12px;
  display: flex; align-items: center; gap: 8px; transition: background .1s;
}
.cm-item:hover { background: var(--sel); }
.cm-item.danger { color: var(--red); }
#context-menu hr { border: none; border-top: 1px solid var(--border2); margin: 3px 0; }

/* ── NOTIFICATIONS ─────────────────────────────────────── */
#notifications { position: fixed; bottom: 32px; right: 16px; z-index: 2000; display: flex; flex-direction: column; gap: 8px; }
.notif {
  padding: 10px 16px; border-radius: 10px; font-size: 12px;
  box-shadow: 0 4px 20px rgba(0,0,0,.1); animation: slideIn .2s ease; max-width: 280px; font-family: inherit;
}
.notif.success { background: #fff; color: #1a7f37; border-left: 3px solid var(--green); border: 1px solid #d4f0db; }
.notif.error   { background: #fff; color: var(--red);   border-left: 3px solid var(--red);   border: 1px solid #ffd9d7; }
.notif.info    { background: #fff; color: var(--accent); border-left: 3px solid var(--accent); border: 1px solid #cce4ff; }
@keyframes slideIn { from { transform: translateX(100%); opacity: 0 } to { transform: none; opacity: 1 } }

/* ── MODAL ──────────────────────────────────────────────── */
.modal {
  position: fixed; inset: 0; background: rgba(0,0,0,.2);
  display: flex; align-items: center; justify-content: center; z-index: 1000;
  backdrop-filter: blur(4px);
}
.modal-content {
  background: var(--panel); border: 1px solid var(--border); border-radius: 16px;
  padding: 24px 28px; min-width: 340px; display: flex; flex-direction: column; gap: 12px;
  box-shadow: 0 20px 60px rgba(0,0,0,.12);
}
.modal-content h3 { font-size: 15px; font-weight: 600; letter-spacing: -.02em; }
.modal-content input, .modal-content select {
  padding: 8px 12px; background: var(--panel2); border: 1px solid var(--border);
  border-radius: 8px; color: var(--text); font-family: inherit; font-size: 13px; width: 100%; outline: none;
}
.modal-content input:focus, .modal-content select:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(0,113,227,.1); }
.modal-actions { display: flex; gap: 8px; justify-content: flex-end; }
.btn-sm { padding: 7px 16px; border: none; border-radius: 980px; font-size: 12px; cursor: pointer; font-family: inherit; transition: all .12s; }
.btn-sm.ghost { background: transparent; border: 1px solid var(--border); color: var(--text2); }
.btn-sm.ghost:hover { border-color: var(--text); color: var(--text); }
.btn-sm.primary { background: var(--accent); color: #fff; }
.btn-sm.primary:hover { background: #0064cc; }

/* ── SCROLLBARS ──────────────────────────────────────────── */
::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #b8b8bd; }