:root {
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;

  --bg: #0b0c0f;
  --bg-raised: #131519;
  --bg-input: #17191e;
  --border: #262a31;
  --border-strong: #34383f;
  --text: #eef0f3;
  --text-dim: #9aa1ab;
  --text-faint: #5c626c;
  --accent: #4f7cff;
  --radius: 10px;
  --radius-sm: 6px;
}

* { box-sizing: border-box; }

html, body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Inter, Roboto, sans-serif;
  height: 100%;
}

body { margin: 0; }

.app { min-height: 100vh; display: flex; flex-direction: column; }

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--border);
}

.brand { display: flex; align-items: center; gap: var(--space-2); }

.brand-mark {
  width: 18px;
  height: 18px;
  border-radius: 5px;
  background: var(--accent);
}

.brand-name { font-weight: 600; font-size: 15px; letter-spacing: -0.01em; }

.topbar-status {
  font-size: 12px;
  color: var(--text-faint);
}

.topbar-status.ok { color: #3ecf7e; }
.topbar-status.err { color: #f26363; }

.layout {
  flex: 1;
  display: grid;
  grid-template-columns: 400px 1fr;
  gap: var(--space-5);
  padding: var(--space-5);
  max-width: 1440px;
  width: 100%;
  margin: 0 auto;
}

.panel {
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: var(--space-5);
}

.form-panel {
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
  align-self: start;
}

.field { display: flex; flex-direction: column; gap: var(--space-2); }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); }

label {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-dim);
}

.optional { font-weight: 400; color: var(--text-faint); }

input[type="text"], select {
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  padding: 10px 12px;
  font-size: 14px;
  outline: none;
  width: 100%;
}

input[type="text"]:focus, select:focus {
  border-color: var(--accent);
}

.template-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3);
}

.template-card {
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  cursor: pointer;
  background: var(--bg-input);
  text-align: left;
  padding: 0;
}

.template-card.active {
  border-color: var(--accent);
}

.template-card img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  display: block;
  background: #0e0f12;
}

.template-card .template-name {
  display: block;
  padding: var(--space-2) var(--space-3);
  font-size: 12px;
  color: var(--text-dim);
}

.accent-row { display: flex; align-items: center; gap: var(--space-3); }

input[type="color"] {
  width: 40px;
  height: 36px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg-input);
  padding: 3px;
  cursor: pointer;
}

.accent-hex { font-size: 13px; color: var(--text-dim); font-variant-numeric: tabular-nums; }

.toggle-label {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  cursor: pointer;
  font-size: 14px;
  color: var(--text);
  font-weight: 500;
}

.dropzone {
  margin-top: var(--space-2);
  border: 1.5px dashed var(--border-strong);
  border-radius: var(--radius-sm);
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.dropzone.drag { border-color: var(--accent); background: rgba(79, 124, 255, 0.06); }

.dropzone-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-1);
  text-align: center;
  padding: var(--space-4);
  font-size: 13px;
  color: var(--text-dim);
}

.dropzone-hint { font-size: 11px; color: var(--text-faint); }

.dropzone-preview {
  width: 100%;
  max-height: 160px;
  object-fit: contain;
  padding: var(--space-2);
}

.preview-panel {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.preview-frame {
  position: relative;
  width: 100%;
  aspect-ratio: 1280 / 720;
  background: #060708;
  border-radius: var(--radius-sm);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
}

.preview-frame img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: none;
}

.preview-frame img.loaded { display: block; }

.preview-empty, .preview-loading {
  position: absolute;
  color: var(--text-faint);
  font-size: 13px;
}

.preview-loading {
  background: rgba(0, 0, 0, 0.55);
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-dim);
}

.preview-meta {
  font-size: 12px;
  color: var(--text-faint);
  font-variant-numeric: tabular-nums;
  min-height: 16px;
}

.preview-actions { display: flex; gap: var(--space-3); }

.btn {
  background: var(--bg-input);
  border: 1px solid var(--border-strong);
  color: var(--text);
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
}

.btn:hover:not(:disabled) { border-color: var(--text-dim); }
.btn:disabled { opacity: 0.45; cursor: not-allowed; }

.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #08090b;
}

.btn-primary:hover:not(:disabled) { filter: brightness(1.08); }

@media (max-width: 880px) {
  .layout { grid-template-columns: 1fr; padding: var(--space-4); gap: var(--space-4); }
  .field-row { grid-template-columns: 1fr; }
  .form-panel { order: 2; }
  .preview-panel { order: 1; }
}