:root {
  --bg: #f4f7fb;
  --bg-top: #f8fbff;
  --surface: #ffffff;
  --surface-alt: #f8fafc;
  --text: #12263a;
  --text-soft: #526377;
  --text-faint: #6b7c93;

  --brand: #0f4c81;
  --brand-dark: #0b3559;
  --brand-light: #e8f1f8;

  --border: #d9e2ec;
  --border-strong: #bcccdc;

  --warning-bg: #fff7e6;
  --warning-border: #f2d49b;

  --danger-bg: #fff5f5;
  --danger-border: #f5c2c7;
  --danger-accent: rgb(186, 12, 47);

  --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.06);
  --shadow-md: 0 10px 30px rgba(15, 23, 42, 0.08);

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --pill: 999px;

  --max-width: 1360px;
  --transition: 0.18s ease;
}

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

html {
  font-size: 16px;
}

body {
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top, rgba(15, 76, 129, 0.08), transparent 30%),
    linear-gradient(180deg, var(--bg-top) 0%, var(--bg) 100%);
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: var(--brand);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

button,
input,
select,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

.hidden {
  display: none !important;
}

.app-shell {
  width: min(var(--max-width), calc(100% - 2rem));
  margin: 0 auto;
  padding: 2rem 0 3rem;
}

/* Header */

.page-header {
  margin-bottom: 1.5rem;
}

.page-header__inner {
  display: grid;
  gap: 1rem;
  padding: 1.5rem;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, rgba(15, 76, 129, 0.98), rgba(11, 53, 89, 0.98));
  color: #fff;
  box-shadow: var(--shadow-md);
}

.page-header__content {
  max-width: 760px;
}

.eyebrow {
  margin: 0 0 0.5rem;
  font-size: 0.85rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  opacity: 0.9;
}

.page-header h1 {
  margin: 0 0 0.75rem;
  font-size: clamp(2rem, 3vw, 2.75rem);
  line-height: 1.05;
  letter-spacing: -0.03em;
}

.lede {
  margin: 0;
  max-width: 60ch;
  color: rgba(255, 255, 255, 0.92);
  line-height: 1.65;
}

/* Tool switcher */

.tool-switcher {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.tool-switcher button {
  appearance: none;
  border: 1px solid rgba(255, 255, 255, 0.22);
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  border-radius: var(--pill);
  padding: 0.82rem 1rem;
  font-weight: 700;
  transition: background var(--transition), transform var(--transition), border-color var(--transition);
}

.tool-switcher button:hover {
  background: rgba(255, 255, 255, 0.16);
  transform: translateY(-1px);
}

.tool-switcher button.active {
  background: #fff;
  color: var(--brand-dark);
  border-color: #fff;
}

/* Layout */

.layout {
  display: grid;
  grid-template-columns: minmax(0, 1.28fr) minmax(340px, 0.92fr);
  gap: 1.5rem;
  align-items: start;
}

.controls-column,
.preview-column {
  min-width: 0;
}

.controls-column {
  display: grid;
  gap: 1rem;
}

.preview-sticky {
  position: sticky;
  top: 1rem;
  display: grid;
  gap: 1rem;
}

/* Cards */

.card {
  background: var(--surface);
  border: 1px solid rgba(15, 23, 42, 0.06);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.guidance-card,
.preview-card,
.copy-steps {
  padding: 1.25rem;
}

.guidance-card h2,
.preview-card h2,
.copy-steps h3,
.section-heading h2 {
  margin: 0;
  line-height: 1.2;
}

.section-heading {
  display: grid;
  gap: 0.45rem;
  margin-bottom: 1rem;
}

.section-heading p,
.guidance-card > p,
.copy-steps p,
.page-footer,
.preview-card__title p {
  margin: 0;
  color: var(--text-soft);
  line-height: 1.65;
}

.callout {
  margin-top: 1rem;
  padding: 1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}

.callout--warning {
  background: var(--warning-bg);
  border-color: var(--warning-border);
}

.callout h3 {
  margin: 0 0 0.75rem;
  font-size: 1rem;
}

.callout ul,
.copy-steps ol {
  margin: 0;
  padding-left: 1.15rem;
  line-height: 1.7;
}

/* Form */

.form-card {
  overflow: hidden;
  padding: 0;
}

.form-section {
  padding: 1.25rem;
  border-bottom: 1px solid var(--border);
}

.form-section:last-child {
  border-bottom: 0;
}

.field {
  display: grid;
  gap: 0.55rem;
}

label {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 0.55rem;
  align-items: baseline;
  font-weight: 700;
  color: var(--text);
}

.req {
  color: var(--danger-accent);
}

.note {
  font-weight: 500;
  font-size: 0.88rem;
  color: var(--text-faint);
}

.field-help {
  color: var(--text-soft);
  font-size: 0.92rem;
  line-height: 1.55;
}

.dual {
  display: grid;
  gap: 0.9rem;
}

.dual--triple {
  grid-template-columns: 180px minmax(180px, 220px) minmax(0, 1fr);
}

.dual--pair {
  grid-template-columns: 180px minmax(0, 1fr);
}

#f_phone .dual {
  margin-bottom: 0.85rem;
}

#f_phone .dual:last-of-type {
  margin-bottom: 0;
}

input,
select,
textarea {
  width: 100%;
  min-height: 46px;
  padding: 0.8rem 0.95rem;
  border: 1px solid var(--border-strong);
  border-radius: 12px;
  background: #fff;
  color: var(--text);
  transition:
    border-color var(--transition),
    box-shadow var(--transition),
    background var(--transition);
}

textarea {
  min-height: 92px;
  resize: vertical;
}

input::placeholder,
textarea::placeholder {
  color: #7b8794;
}

input:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: rgba(15, 76, 129, 0.65);
  box-shadow: 0 0 0 4px rgba(15, 76, 129, 0.12);
}

/* Validation */

#validation_warnings {
  margin-bottom: 1rem !important;
}

.subtle-warning {
  display: none;
  margin-top: 0.15rem;
  padding: 0.75rem 0.9rem;
  border-radius: 12px;
  background: var(--danger-bg);
  border: 1px solid var(--danger-border);
  color: var(--danger-accent);
  font-size: 0.92rem;
  line-height: 1.5;
}

.subtle-warning.show {
  display: block;
}

/* Preview */

.preview-card {
  overflow: hidden;
}

.preview-card__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1rem;
}

.preview-card__title {
  display: grid;
  gap: 0.35rem;
}

.preview-toolbar {
  display: grid;
  gap: 0.45rem;
  min-width: 180px;
}

.preview-toolbar label {
  font-size: 0.92rem;
  font-weight: 700;
}

.preview-toolbar select {
  min-height: 42px;
}

.preview-surface {
  min-height: 250px;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: linear-gradient(180deg, #fbfdff 0%, #f5f8fb 100%);
  overflow: auto;
}

#preview_rendered {
  min-height: 200px;
}

#preview_code,
.preview-code {
  margin: 0;
  min-height: 200px;
  padding: 1rem;
  border-radius: 12px;
  background: #0f172a;
  color: #e2e8f0;
  overflow: auto;
  white-space: pre-wrap;
  word-break: break-word;
  font-size: 0.92rem;
  line-height: 1.6;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
}

/* Footer / helper card */

.copy-steps h3 {
  font-size: 1.05rem;
  margin-bottom: 0.75rem;
}

.page-footer {
  padding: 0.1rem 0.2rem 0;
  font-size: 0.92rem;
}

/* Responsive */

@media (max-width: 1120px) {
  .layout {
    grid-template-columns: 1fr;
  }

  .preview-sticky {
    position: static;
  }
}

@media (max-width: 860px) {
  .dual--triple,
  .dual--pair {
    grid-template-columns: 1fr;
  }

  .preview-card__header {
    flex-direction: column;
    align-items: stretch;
  }

  .preview-toolbar {
    min-width: 0;
  }
}

@media (max-width: 720px) {
  .app-shell {
    width: min(100% - 1rem, var(--max-width));
    padding-top: 1rem;
  }

  .page-header__inner,
  .guidance-card,
  .preview-card,
  .copy-steps {
    padding: 1rem;
  }

  .form-section {
    padding: 1rem;
  }

  .tool-switcher {
    flex-direction: column;
  }

  .tool-switcher button {
    width: 100%;
  }

  .page-header h1 {
    font-size: 1.9rem;
  }

  .preview-surface {
    min-height: 360px;
  }
}