:root {
  --paper: #efe9dc;
  --paper-line: #d9d0ba;
  --ink: #1c2b3a;
  --ink-soft: #445a6b;
  --tech-line: #3d5a73;
  --accent: #c9973a;
  --danger: #a8442f;
  --panel-bg: #f7f3e9;
  --font-display: 'Barlow Condensed', 'Arial Narrow', sans-serif;
  --font-mono: 'JetBrains Mono', 'Courier New', monospace;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--paper-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--paper-line) 1px, transparent 1px);
  background-size: 24px 24px;
  color: var(--ink);
  font-family: var(--font-display);
  font-size: 17px;
  line-height: 1.45;
  min-height: 100vh;
}

.sheet {
  max-width: 1180px;
  margin: 0 auto;
  padding: 32px 20px 64px;
}

/* ---------- Masthead ---------- */

.masthead {
  display: flex;
  align-items: center;
  gap: 20px;
  border-bottom: 3px solid var(--ink);
  padding-bottom: 20px;
  margin-bottom: 32px;
}

.masthead-mark {
  font-size: 40px;
  color: var(--accent);
  line-height: 1;
  transform: rotate(-8deg);
}

.masthead-text h1 {
  margin: 0 0 4px;
  font-size: clamp(28px, 4vw, 38px);
  font-weight: 700;
  letter-spacing: 0.01em;
}

.masthead-text p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 16px;
  max-width: 56ch;
}

/* ---------- Workspace grid ---------- */

.workspace {
  display: grid;
  grid-template-columns: minmax(320px, 420px) 1fr;
  gap: 24px;
  align-items: start;
}

@media (max-width: 860px) {
  .workspace {
    grid-template-columns: 1fr;
  }
}

.panel {
  background: var(--panel-bg);
  border: 1.5px solid var(--ink);
  position: relative;
  padding: 24px;
}

.panel::before,
.panel::after {
  content: '';
  position: absolute;
  width: 10px;
  height: 10px;
  border: 1.5px solid var(--tech-line);
  top: -1.5px;
}

.panel::before {
  left: -1.5px;
  border-right: none;
  border-bottom: none;
}

.panel::after {
  right: -1.5px;
  border-left: none;
  border-bottom: none;
}

.panel h2 {
  margin: 0 0 6px;
  font-size: 22px;
  font-weight: 600;
  text-transform: lowercase;
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.panel-index {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--accent);
  border: 1px solid var(--accent);
  padding: 1px 6px;
}

.panel-hint {
  margin: 0 0 20px;
  color: var(--ink-soft);
  font-size: 14.5px;
}

/* ---------- Design selector ---------- */

.design-panel {
  margin-bottom: 24px;
}

.family-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}

.family-tab {
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-transform: lowercase;
  border: 1.5px solid var(--ink-soft);
  background: transparent;
  color: var(--ink-soft);
  padding: 6px 16px;
  cursor: pointer;
}

.family-tab:hover {
  border-color: var(--ink);
  color: var(--ink);
}

.family-tab.is-active {
  border-color: var(--ink);
  background: var(--ink);
  color: var(--paper);
}

.design-groups {
  display: flex;
  flex-direction: column;
}

.subfamily-group + .subfamily-group {
  margin-top: 18px;
}

.subfamily-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-soft);
  letter-spacing: 0.03em;
  text-transform: uppercase;
  margin-bottom: 8px;
}

.design-selector {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 12px;
}

.design-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 8px;
  text-align: left;
  border: 1.5px solid var(--ink-soft);
  background: #fffdf8;
  padding: 14px;
  cursor: pointer;
  font-family: var(--font-display);
  color: var(--ink);
}

.design-card:hover {
  border-color: var(--ink);
}

.design-card.is-selected {
  border-color: var(--accent);
  border-width: 2px;
  background: #fbf1de;
}

.design-card i {
  font-size: 26px;
  color: var(--tech-line);
}

.design-card.is-selected i {
  color: var(--accent);
}

.design-card-label {
  font-size: 18px;
  font-weight: 600;
}

.design-card-description {
  font-size: 13px;
  color: var(--ink-soft);
  line-height: 1.4;
}

/* ---------- Form ---------- */

.fields {
  display: grid;
  gap: 14px;
}

.field {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 8px;
  border-bottom: 1px dashed var(--paper-line);
  padding-bottom: 10px;
}

.field label {
  font-size: 15px;
  color: var(--ink);
}

.field .field-key {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-soft);
  letter-spacing: 0.02em;
}

.field-input {
  display: flex;
  align-items: center;
  gap: 6px;
}

.field input[type='number'] {
  width: 88px;
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  background: #fffdf8;
  border: 1.5px solid var(--ink);
  padding: 6px 8px;
  text-align: right;
}

.field input[type='number']:focus {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

.field input[type='number'].field-invalid {
  border-color: var(--danger);
  outline-color: var(--danger);
}

.field .unit {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-soft);
  width: 20px;
}

.field.optional .field-key::after {
  content: ' · opcional';
  color: var(--accent);
}

.loading-fields {
  color: var(--ink-soft);
  font-family: var(--font-mono);
  font-size: 14px;
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: 0.02em;
  border: 1.5px solid var(--ink);
  background: transparent;
  color: var(--ink);
  padding: 10px 18px;
  cursor: pointer;
  transition: background-color 0.12s ease, color 0.12s ease;
}

.btn:hover {
  background: var(--ink);
  color: var(--paper);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  background: transparent;
  color: var(--ink);
}

.btn-primary {
  margin-top: 18px;
  width: 100%;
  justify-content: center;
  background: var(--accent);
  border-color: var(--accent);
  color: var(--ink);
}

.btn-primary:hover:not(:disabled) {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--accent);
}

.btn-secondary {
  font-size: 15px;
  padding: 8px 14px;
}

.form-status {
  margin: 12px 0 0;
  font-size: 14px;
  min-height: 1.4em;
}

.form-status.error {
  color: var(--danger);
}

.form-status.success {
  color: var(--tech-line);
}

/* ---------- Preview ---------- */

.preview-surface {
  border: 1.5px solid var(--ink-soft);
  background:
    linear-gradient(#e3dcc8 1px, transparent 1px),
    linear-gradient(90deg, #e3dcc8 1px, transparent 1px);
  background-size: 12px 12px;
  background-color: #fffdf8;
  min-height: 420px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
  overflow: auto;
}

.preview-placeholder {
  color: var(--ink-soft);
  font-size: 15px;
  text-align: center;
  max-width: 40ch;
  margin: 0;
}

.preview-surface.is-loading .preview-placeholder {
  font-family: var(--font-mono);
}

.preview-surface svg {
  max-width: 100%;
  height: auto;
  display: block;
}

.downloads {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 16px;
}

.downloads-hint {
  margin: 10px 0 0;
  font-size: 13px;
  color: var(--ink-soft);
  line-height: 1.5;
}

.downloads-hint strong {
  color: var(--ink);
}

/* ---------- Footer ---------- */

.colophon {
  margin-top: 40px;
  border-top: 1px solid var(--paper-line);
  padding-top: 16px;
  color: var(--ink-soft);
  font-size: 13px;
}

.colophon p {
  margin: 0;
}

@media (max-width: 480px) {
  .field {
    grid-template-columns: 1fr;
    align-items: flex-start;
  }
  .field-input {
    justify-content: flex-end;
  }
  .downloads {
    flex-direction: column;
  }
}