/* ===================================================================
   WebFEA2 — WASM demo styles
   - Inter / system 산세리프 + JetBrains Mono 모노폰트.
   - 컬러: 다크 nav, 밝은 sidebar, 짙은 viewport.
   - tree / form 은 Python qt_demo 의 위계감 비슷하게 좁은 indent + subtle row.
   =================================================================== */

:root {
  --bg-app:        #f5f6f8;
  --bg-pane:       #ffffff;
  --bg-pane-alt:   #fafbfc;
  --bg-header:     #161b27;
  --bg-section:    #eef0f4;
  --bg-viewport:   #1a1d27;

  --color-text:    #1f2330;
  --color-muted:   #6c7382;
  --color-border:  #dde0e6;
  --color-divider: #e6e8ee;

  --color-accent:        #2563eb;
  --color-accent-hover:  #1d4ed8;
  --color-accent-soft:   #dbeafe;
  --color-success:       #16a34a;
  --color-warn:          #ca8a04;
  --color-danger:        #dc2626;

  --hover:        rgba(37, 99, 235, 0.08);
  --selected:     rgba(37, 99, 235, 0.15);

  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 4px 12px rgba(15, 23, 42, 0.08);

  --radius: 6px;
  --radius-sm: 4px;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "Inter",
               "Helvetica Neue", Arial, sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  font-family: var(--font-sans);
  font-size: 13px;
  color: var(--color-text);
  background: var(--bg-app);
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
button { font: inherit; cursor: pointer; }
button:disabled { opacity: 0.45; cursor: not-allowed; }

/* ============================== topbar ============================== */
#topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.55rem 1rem;
  background: var(--bg-header);
  color: #f5f7fb;
  border-bottom: 1px solid #0a0d14;
  box-shadow: var(--shadow-sm);
}
.brand {
  display: flex;
  align-items: baseline;
  gap: 0.55rem;
}
.brand-logo {
  font-size: 1.05rem;
  color: #6f96ff;
}
.brand-text {
  font-weight: 700;
  letter-spacing: 0.04em;
  font-size: 0.95rem;
}
.brand-tag {
  font-size: 0.72rem;
  letter-spacing: 0.05em;
  color: #a4abbc;
  text-transform: uppercase;
}

.toolbar { display: flex; gap: 0.55rem; align-items: center; }

.file-btn { position: relative; cursor: pointer; }
.file-btn input { position: absolute; inset: 0; opacity: 0; cursor: pointer; }
.file-btn span {
  display: inline-block;
  padding: 5px 12px;
  border: 1px solid #3a4258;
  border-radius: var(--radius-sm);
  background: #2a3145;
  color: #e8eaf0;
  font-size: 0.78rem;
  font-weight: 500;
  transition: background 0.12s ease;
}
.file-btn:hover span { background: #3a4258; }

.bg-control { display: flex; align-items: center; gap: 0.35rem; font-size: 0.72rem; color: #aeb6c6; }
.bg-control select {
  background: #2a3146;
  color: #e6e9f0;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
  padding: 3px 6px;
  font-size: 0.72rem;
}

.pill {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 0.74rem;
  font-weight: 500;
  background: #2a3145;
  color: #c8ccd9;
  letter-spacing: 0.02em;
  font-family: var(--font-mono);
}
.pill.ok  { background: #14422a; color: #92e6b3; }
.pill.err { background: #501f24; color: #f5b8bd; }

/* ============================== layout ============================== */
#workbench {
  flex: 1;
  display: grid;
  grid-template-columns: 340px 1fr;
  min-height: 0;
}
#sidebar {
  display: grid;
  /* tree pane: 고정 max-height (32vh). property pane: 잔여 영역. action bar: auto. */
  grid-template-rows: minmax(180px, 32vh) minmax(180px, 1fr) auto;
  border-right: 1px solid var(--color-divider);
  background: var(--bg-pane);
  min-width: 0;
}
.pane {
  display: flex;
  flex-direction: column;
  border-bottom: 1px solid var(--color-divider);
  min-height: 0;
}
.pane-header {
  padding: 0.45rem 0.85rem;
  font-weight: 600;
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-muted);
  background: var(--bg-section);
  border-bottom: 1px solid var(--color-divider);
}

.empty-hint {
  color: var(--color-muted);
  font-style: italic;
  padding: 0.85rem;
  font-size: 0.82rem;
}

/* ============================== tree ============================== */
.tree {
  overflow: auto;
  flex: 1;
  padding: 0.3rem 0.25rem;
  font-size: 0.83rem;
}
.tree ul {
  list-style: none;
  margin: 0;
  padding-left: 0.95rem;
}
.tree > ul.tree-root {
  padding-left: 0.15rem;
  padding-top: 0.15rem;
}
.tree-row {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  padding: 3px 6px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  user-select: none;
  position: relative;
  transition: background-color 0.1s ease;
}
.tree-row:hover { background: var(--hover); }
.tree-row.selected {
  background: var(--selected);
  font-weight: 500;
}
/* case row: twisty/icon 제거됐으므로 padding-left 줄여서 텍스트를 왼쪽에 가깝게. */
.tree-row.case-root {
  padding-left: 4px;
  gap: 0.5rem;
}
.tree-row.case-root .label {
  font-weight: 700;
}
/* case-root 의 badge 가 label 앞에 — 위치는 일반 badge 와 다름. */
.tree-row.case-root .badge {
  margin-left: 0;
}

/* active case 강조 — 좌측 accent bar. */
.tree-row.active-case::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 3px;
  border-radius: 2px;
  background: var(--color-accent, #4a90ff);
}
.tree-row .twisty {
  width: 0.8em;
  text-align: center;
  color: #9ba0ad;
  font-size: 0.65em;
  line-height: 1;
}
.tree-row .twisty.twisty-clickable {
  cursor: pointer;
  transition: color 0.1s ease;
}
.tree-row .twisty.twisty-clickable:hover { color: var(--color-accent, #4a90ff); }

.tree-row .row-delete {
  margin-left: 0.25rem;
  width: 1.2em;
  height: 1.2em;
  padding: 0;
  border: none;
  background: transparent;
  color: #9ba0ad;
  font-size: 0.95rem;
  line-height: 1;
  cursor: pointer;
  border-radius: var(--radius-sm);
  visibility: hidden;
  transition: background 0.1s ease, color 0.1s ease;
}
.tree-row:hover .row-delete { visibility: visible; }
.tree-row .row-delete:hover {
  background: #f3c4c4;
  color: #b03030;
}

/* drag & drop overlay */
body.dragging::after {
  content: "📂  Drop .step here";
  position: fixed;
  inset: 0;
  background: rgba(74, 144, 255, 0.10);
  border: 3px dashed var(--color-accent, #4a90ff);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-accent, #4a90ff);
  pointer-events: none;
  z-index: 9999;
}
.tree-row .label {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.tree-row .badge {
  background: #e3e6ec;
  color: #4a505d;
  border-radius: 999px;
  padding: 1px 8px;
  font-size: 0.7rem;
  font-family: var(--font-mono);
  font-weight: 500;
}
.tree-row .badge.kind-mesh {
  background: #dbeafe;
  color: #1e40af;
}
.tree-row .badge.kind-cad {
  background: #fef3c7;
  color: #92400e;
}
.tree-row.disabled { opacity: 0.5; pointer-events: none; }

.tree input[type="checkbox"] {
  margin: 0;
  width: 13px;
  height: 13px;
  cursor: pointer;
  accent-color: var(--color-accent);
}
.tree-check-placeholder {
  display: inline-block;
  width: 13px;
  height: 13px;
}

/* tree icons — 작은 squared dot/sigil. Python qt_demo 는 안 썼지만 가독성 향상. */
.tree-icon {
  width: 11px;
  height: 11px;
  border-radius: 2px;
  display: inline-block;
  flex-shrink: 0;
  margin-right: 1px;
}
.icon-mesh     { background: #6f96ff; }
.icon-cad      { background: #d97706; }
.icon-geometry { background: #94a3b8; }
.icon-material { background: #a78bfa; }
.icon-bc       { background: #dc2626; }
.icon-lc       { background: #16a34a; }
.icon-result   { background: #f59e0b; }

/* ============================== property ============================== */
.property {
  overflow: auto;
  padding: 0.85rem 0.95rem;
  flex: 1;
}
.form h3.form-title {
  margin: 0 0 0.7rem 0;
  font-size: 0.92rem;
  font-weight: 600;
  color: #1f2330;
  letter-spacing: 0.01em;
}
.form-hint {
  margin: 0.5rem 0 0 0;
  font-size: 0.75rem;
  color: var(--color-muted);
  line-height: 1.4;
}

.form .kv {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 5px 14px;
  margin: 0 0 0.85rem 0;
}
.form .kv dt {
  color: var(--color-muted);
  font-size: 0.78rem;
}
.form .kv dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

/* CAD case property panel 의 mesh size input. */
.mesh-size-input {
  font: inherit;
  font-family: var(--font-mono);
  width: 8em;
  padding: 3px 6px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: white;
  color: var(--color-text);
  font-size: 0.8rem;
}
.mesh-size-input:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 2px var(--color-accent-soft);
}

.fields {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 7px 12px;
  margin-bottom: 0.85rem;
  align-items: center;
}
.load-type-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin: -0.15rem 0 0.7rem 0;
  padding: 5px 7px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--bg-pane-alt);
  font-size: 0.78rem;
}
.load-type-row span {
  color: var(--color-muted);
}
.load-type-row strong {
  color: var(--color-text);
  font-weight: 600;
}
.fields label {
  color: var(--color-muted);
  font-size: 0.78rem;
}
.fields input[type="text"],
.fields input[type="number"],
.fields select {
  font: inherit;
  width: 100%;
  padding: 4px 7px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: white;
  color: var(--color-text);
  font-size: 0.8rem;
}
.fields input[type="text"],
.fields input[type="number"] {
  font-family: var(--font-mono);
}
.fields input[type="text"]:focus,
.fields input[type="number"]:focus,
.fields select:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 2px var(--color-accent-soft);
}
.fields input[type="checkbox"] {
  width: 14px; height: 14px;
  accent-color: var(--color-accent);
}
.fields .checkbox-wrap {
  display: flex;
  align-items: center;
}
.fields .color-field input[type="color"] {
  width: 38px;
  height: 22px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: white;
  padding: 1px;
  cursor: pointer;
}

.color-swatch {
  display: inline-block;
  width: 28px;
  height: 16px;
  border: 1px solid #b6bac3;
  border-radius: 3px;
  vertical-align: middle;
}

/* picking */
.picking {
  border: 1px dashed var(--color-border);
  padding: 0.6rem 0.7rem;
  border-radius: var(--radius);
  margin-bottom: 0.85rem;
  background: var(--bg-pane-alt);
}
/* face/edge 선택 모드 토글 (segmented control) */
.picking-mode {
  display: flex;
  gap: 0;
  margin-bottom: 7px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  width: fit-content;
}
/* `.picking button` (specificity 0-1-1) 보다 높게 — 부모 클래스로 스코프해 segment 간
   margin/테두리가 안 깨지게. */
.picking-mode .picking-mode-btn {
  margin: 0;
  padding: 4px 16px;
  border: none;
  border-right: 1px solid var(--color-border);
  background: white;
  color: var(--color-muted);
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.1s ease, color 0.1s ease;
}
.picking-mode .picking-mode-btn:last-child { border-right: none; }
.picking-mode .picking-mode-btn:hover { background: var(--hover); }
.picking-mode .picking-mode-btn.active {
  background: var(--color-accent);
  color: white;
}
.picking-hint {
  font-size: 0.76rem;
  color: var(--color-muted);
  margin-bottom: 5px;
  line-height: 1.4;
}
.picking-count {
  font-weight: 600;
  margin-bottom: 6px;
  font-size: 0.82rem;
  color: var(--color-text);
  font-family: var(--font-mono);
}
.picking button { margin-right: 0.4rem; }

/* form action buttons */
.form-actions {
  display: flex;
  gap: 0.4rem;
  margin-top: 0.6rem;
  border-top: 1px solid var(--color-divider);
  padding-top: 0.7rem;
}
.form-actions button,
.btn-secondary {
  padding: 5px 14px;
  border: 1px solid var(--color-border);
  background: white;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 500;
  transition: background 0.1s ease, border-color 0.1s ease;
}
.form-actions button:hover,
.btn-secondary:hover {
  background: var(--color-accent-soft);
  border-color: var(--color-accent);
}
.form-actions button.primary {
  background: var(--color-accent);
  color: white;
  border-color: var(--color-accent-hover);
}
.form-actions button.primary:hover {
  background: var(--color-accent-hover);
}

/* category Add button */
.add-btn {
  padding: 7px 12px;
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--bg-pane-alt);
  width: 100%;
  font-size: 0.82rem;
  color: var(--color-text);
  font-weight: 500;
  transition: background 0.12s ease, border-color 0.12s ease, color 0.12s ease;
}
.add-btn:hover {
  background: var(--color-accent-soft);
  border-color: var(--color-accent);
  color: var(--color-accent-hover);
}

/* ============================== action bar ============================== */
#action-bar {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.55rem 0.85rem;
  border-top: 1px solid var(--color-divider);
  background: var(--bg-section);
}
#action-bar #solveBtn {
  padding: 6px 18px;
  background: var(--color-success);
  color: white;
  border: 1px solid #15803d;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.85rem;
  letter-spacing: 0.02em;
  transition: background 0.1s ease;
}
#action-bar #solveBtn:hover:not(:disabled) { background: #15803d; }
#action-bar .pill {
  background: #d8dce2;
  color: #4a505a;
}
#action-bar .pill.ok  { background: #14422a; color: #92e6b3; }
#action-bar .pill.err { background: #501f24; color: #f5b8bd; }

/* ============================== viewport ============================== */
#viewport {
  position: relative;
  background: var(--bg-viewport);
  min-width: 0;
  overflow: hidden;
}
#canvas {
  width: 100%;
  height: 100%;
  display: block;
  outline: none;
}
#viewport-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #6a6f7a;
  pointer-events: none;
}

#viewport-legend {
  position: absolute;
  left: 12px;
  bottom: 12px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  background: rgba(20, 24, 35, 0.6);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.08);
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.7rem;
  color: #cdd2dc;
  pointer-events: none;
  font-family: var(--font-mono);
}
#viewport-legend .legend-item {
  display: flex;
  align-items: center;
  gap: 6px;
}
#viewport-legend .sym {
  display: inline-block;
  width: 12px;
  text-align: center;
  font-size: 0.8rem;
  line-height: 1;
}
#viewport-legend .sym-bc   { color: #d92626; }   /* ▲ boundary condition */
#viewport-legend .sym-lc   { color: #c061d9; }   /* ➜ loading condition */
#viewport-legend .sym-peak { color: #2dd360; }   /* ● peak displacement */