/* =============================================
   DrawingLens – Main Stylesheet
   ============================================= */

/* ---------- CSS Custom Properties ---------- */
:root {
  --clr-primary:       #4f46e5;
  --clr-primary-dark:  #4338ca;
  --clr-primary-light: #e0e7ff;
  --clr-on-primary:    #ffffff;
  --clr-accent:        #f59e0b;

  --clr-bg:            #f8fafc;
  --clr-surface:       #ffffff;
  --clr-surface-2:     #f1f5f9;
  --clr-border:        #e2e8f0;

  --clr-text:          #1e293b;
  --clr-text-muted:    #526077;
  --clr-text-inverse:  #ffffff;
  --clr-border-strong: #7c8799;

  --clr-pass:          #15803d;
  --clr-pass-bg:       #dcfce7;
  --clr-fail:          #b91c1c;
  --clr-fail-bg:       #fee2e2;
  --clr-warn:          #92400e;
  --clr-warn-bg:       #fef3c7;
  --clr-focus:         #4f46e5;

  --radius-sm:  6px;
  --radius-md:  10px;
  --radius-lg:  16px;
  --radius-xl:  24px;

  --shadow-sm:  0 1px 3px rgba(0,0,0,.08), 0 1px 2px rgba(0,0,0,.06);
  --shadow-md:  0 4px 12px rgba(0,0,0,.10), 0 2px 4px rgba(0,0,0,.06);
  --shadow-lg:  0 10px 30px rgba(0,0,0,.12), 0 4px 8px rgba(0,0,0,.06);

  --header-h:   64px;
  --transition: 0.2s ease;
}

/* ---------- Dark Theme ---------- */
[data-theme="dark"] {
  --clr-bg:          #0f172a;
  --clr-surface:     #1e293b;
  --clr-surface-2:   #273548;
  --clr-border:      #334155;
  --clr-text:        #e2e8f0;
  --clr-text-muted:  #94a3b8;
  --clr-primary:     #a5b4fc;
  --clr-primary-dark: #c7d2fe;
  --clr-primary-light: #312e81;
  --clr-on-primary:  #0f172a;
  --clr-text-inverse: #0f172a;
  --clr-border-strong: #7c8799;
  --clr-pass:        #86efac;
  --clr-pass-bg:     #14532d;
  --clr-fail:        #fca5a5;
  --clr-fail-bg:     #7f1d1d;
  --clr-warn:        #fde68a;
  --clr-warn-bg:     #78350f;
  --clr-focus:       #a5b4fc;
  --shadow-sm:  0 1px 3px rgba(0,0,0,.3);
  --shadow-md:  0 4px 12px rgba(0,0,0,.4);
  --shadow-lg:  0 10px 30px rgba(0,0,0,.5);
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background: var(--clr-bg);
  color: var(--clr-text);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background var(--transition), color var(--transition);
}
a { color: var(--clr-primary); text-decoration: none; }
a:hover { text-decoration: underline; }
ul { list-style: none; }
img, svg { display: block; }
button { cursor: pointer; font-family: inherit; }

/* ---------- Layout Helpers ---------- */
.container {
  width: 100%;
  max-width: 1100px;
  margin-inline: auto;
  padding-inline: 1.25rem;
}
main { flex: 1; }

/* =============================================
   HEADER
   ============================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: var(--clr-surface);
  border-bottom: 1px solid var(--clr-border);
  box-shadow: var(--shadow-sm);
  transition: background var(--transition), border-color var(--transition);
}
.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 2rem;
}

/* Logo */
.logo {
  display: flex;
  align-items: center;
  gap: .6rem;
  color: var(--clr-text);
  text-decoration: none;
  flex-shrink: 0;
}
.logo-icon { width: 36px; height: 36px; border-radius: 8px; }
.logo-text {
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: -.5px;
  color: var(--clr-text);
}
.logo-text strong { color: var(--clr-primary); }

/* Nav */
.main-nav { margin-left: auto; }
.main-nav ul { display: flex; gap: .25rem; }
.nav-link {
  display: block;
  padding: .45rem .9rem;
  border-radius: var(--radius-sm);
  color: var(--clr-text-muted);
  font-size: .95rem;
  font-weight: 500;
  transition: background var(--transition), color var(--transition);
}
.nav-link:hover, .nav-link.active {
  background: var(--clr-primary-light);
  color: var(--clr-primary);
  text-decoration: none;
}

/* Header actions */
.header-actions { display: flex; align-items: center; gap: .5rem; }

.btn-icon {
  width: 38px; height: 38px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--clr-border);
  background: var(--clr-surface);
  color: var(--clr-text-muted);
  display: flex; align-items: center; justify-content: center;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}
.btn-icon:hover { background: var(--clr-surface-2); color: var(--clr-text); }
.btn-icon .icon { width: 18px; height: 18px; }

/* Theme toggle icon swap */
:root:not([data-theme="dark"]) .moon-icon { display: none; }
[data-theme="dark"] .sun-icon { display: none; }

/* Mobile menu button */
.btn-mobile-menu {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 38px; height: 38px;
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-sm);
  background: transparent;
  padding: 8px;
}
.btn-mobile-menu span {
  display: block;
  height: 2px;
  background: var(--clr-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* =============================================
   HERO SECTION
   ============================================= */
.hero {
  background: var(--rm-hero-bg);
  padding: 3rem 0 2.5rem;
  text-align: center;
  color: #fff;
}
.hero h1 {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  font-weight: 800;
  letter-spacing: -.5px;
  margin-bottom: .6rem;
}
.hero p {
  font-size: 1.05rem;
  max-width: 560px;
  margin-inline: auto;
}

/* =============================================
   CONVERTER CARD
   ============================================= */
.converter-section { padding: 2.5rem 0 3rem; }

.converter-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  transition: background var(--transition), border-color var(--transition);
}

/* Case conversion buttons */
.case-buttons-section { padding: 1.25rem 1.25rem .75rem; }
.case-buttons-section h2 {
  font-size: .75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--clr-text-muted);
  margin-bottom: .85rem;
}
/* Divider */
.section-divider { height: 1px; background: var(--clr-border); margin: 0 1.25rem; }

/* Action toolbar */
.action-bar {
  display: flex;
  flex-wrap: wrap;
  gap: .6rem;
  padding: 1rem 1.25rem;
  align-items: center;
}

.action-btn {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: .5rem 1rem;
  border-radius: var(--radius-md);
  border: 1.5px solid var(--clr-border);
  background: var(--clr-surface);
  color: var(--clr-text);
  font-size: .875rem;
  font-weight: 500;
  transition: background var(--transition), border-color var(--transition), color var(--transition);
}
.action-btn svg { width: 15px; height: 15px; flex-shrink: 0; }
.action-btn:hover {
  background: var(--clr-surface-2);
  border-color: var(--clr-primary);
  color: var(--clr-primary);
}
.action-btn.danger:hover {
  border-color: #ef4444;
  color: #ef4444;
}
.action-btn.success {
  border-color: #22c55e;
  color: #22c55e;
}

.ml-auto { margin-left: auto; }

/* Toast notification */
.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: var(--clr-text);
  color: var(--clr-text-inverse);
  padding: .65rem 1.4rem;
  border-radius: var(--radius-lg);
  font-size: .9rem;
  font-weight: 500;
  box-shadow: var(--shadow-lg);
  z-index: 999;
  opacity: 0;
  transition: transform .3s ease, opacity .3s ease;
  pointer-events: none;
  white-space: nowrap;
}
.toast.show {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

/* ---------- Accessibility helpers ---------- */
:focus-visible {
  outline: 3px solid var(--clr-focus);
  outline-offset: 2px;
}
.skip-link {
  position: absolute;
  left: 1rem;
  top: -100px;
  z-index: 1000;
  background: var(--clr-primary);
  color: var(--clr-on-primary);
  padding: .5rem 1rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
}
.skip-link:focus { top: .75rem; }

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
.hero code {
  font-family: 'JetBrains Mono', 'Courier New', monospace;
  font-size: .95em;
  background: rgba(255,255,255,.18);
  padding: .05rem .4rem;
  border-radius: var(--radius-sm);
}

/* =============================================
   SETTINGS FORM
   ============================================= */
.card-heading {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: .25rem 1rem;
  padding: 1.25rem 1.25rem 0;
}
.card-heading h2 { font-size: 1.15rem; font-weight: 700; }
.card-heading p { font-size: .875rem; color: var(--clr-text-muted); }

.field-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
  padding: 1.25rem;
}
.field { min-width: 0; }
.field label {
  display: block;
  font-size: .75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--clr-text-muted);
  margin-bottom: .45rem;
}
.input-wrap {
  display: flex;
  align-items: stretch;
  border: 1.5px solid var(--clr-border-strong);
  border-radius: var(--radius-md);
  background: var(--clr-surface);
  overflow: hidden;
  transition: border-color var(--transition), box-shadow var(--transition);
}
.input-wrap:focus-within {
  border-color: var(--clr-primary);
  box-shadow: 0 0 0 3px var(--clr-primary-light);
}
.field.invalid .input-wrap { border-color: var(--clr-fail); }
.input-wrap input,
.input-wrap select {
  flex: 1;
  min-width: 0;
  padding: .6rem .8rem;
  border: none;
  outline: none;
  background: var(--clr-surface);
  color: var(--clr-text);
  font-family: 'JetBrains Mono', 'Courier New', monospace;
  font-size: 1rem;
}
.input-wrap select { font-family: inherit; font-size: .95rem; cursor: pointer; }
.input-unit {
  display: flex;
  align-items: center;
  padding: 0 .75rem;
  background: var(--clr-surface-2);
  border-left: 1.5px solid var(--clr-border);
  color: var(--clr-text-muted);
  font-size: .85rem;
  font-weight: 600;
}
.field-hint {
  font-size: .8rem;
  color: var(--clr-text-muted);
  margin-top: .35rem;
  font-variant-numeric: tabular-nums;
}

/* Messages (validation + accessibility warnings) */
.messages:empty { display: none; }
.messages { padding: 0 1.25rem 1.25rem; display: flex; flex-direction: column; gap: .5rem; }
.message {
  display: flex;
  gap: .6rem;
  align-items: flex-start;
  padding: .7rem .9rem;
  border-radius: var(--radius-md);
  font-size: .875rem;
  line-height: 1.5;
}
.message svg { width: 18px; height: 18px; flex-shrink: 0; margin-top: .1rem; }
.message.error { background: var(--clr-fail-bg); color: var(--clr-fail); }
.message.warn  { background: var(--clr-warn-bg); color: var(--clr-warn); }

/* =============================================
   OPEN FILE
   ============================================= */
.dropzone {
  margin: 1.25rem;
  border: 2px dashed var(--clr-border-strong);
  border-radius: var(--radius-lg);
  background: var(--clr-surface-2);
  padding: 1.75rem 1.25rem;
  text-align: center;
  transition: border-color var(--transition), background var(--transition);
}
.dropzone.dragover { border-color: var(--clr-primary); background: var(--clr-primary-light); }
.dropzone h2 { font-size: 1.15rem; font-weight: 700; margin-bottom: .25rem; }
.dropzone p { font-size: .875rem; color: var(--clr-text-muted); }
.dropzone-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: .6rem;
  margin: 1rem 0 .6rem;
}
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: .45rem;
  padding: .65rem 1.3rem;
  border-radius: var(--radius-md);
  border: none;
  background: var(--clr-primary);
  color: var(--clr-on-primary);
  font-size: .95rem;
  font-weight: 600;
  box-shadow: 0 4px 12px color-mix(in srgb, var(--rm-primary) 30%, transparent);
  transition: background var(--transition), transform .1s;
}
.btn-primary svg { width: 17px; height: 17px; }
.btn-primary:hover { background: var(--clr-primary-dark); }
.btn-primary:active { transform: translateY(1px); }

/* =============================================
   VIEWER
   ============================================= */
.viewer-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 0;
  border-top: 1px solid var(--clr-border);
}
.viewer-main { min-width: 0; display: flex; flex-direction: column; }

.toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .4rem;
  padding: .6rem .75rem;
  border-bottom: 1px solid var(--clr-border);
  background: var(--clr-surface);
}
.tool-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .35rem;
  min-width: 36px;
  height: 36px;
  padding: 0 .6rem;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--clr-border);
  background: var(--clr-surface);
  color: var(--clr-text);
  font-size: .85rem;
  font-weight: 500;
  transition: background var(--transition), border-color var(--transition), color var(--transition);
}
.tool-btn svg { width: 16px; height: 16px; flex-shrink: 0; }
.tool-btn:hover { border-color: var(--clr-primary); color: var(--clr-primary); }
.tool-btn[aria-pressed="true"] {
  background: var(--clr-primary);
  border-color: var(--clr-primary);
  color: var(--clr-on-primary);
}
.tool-btn:disabled { opacity: .45; cursor: not-allowed; }
.toolbar-sep { width: 1px; align-self: stretch; background: var(--clr-border); margin: 0 .2rem; }
.toolbar .bg-select {
  height: 36px;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--clr-border);
  background: var(--clr-surface);
  color: var(--clr-text);
  font-family: inherit;
  font-size: .85rem;
  padding: 0 .5rem;
  cursor: pointer;
}

.viewport {
  position: relative;
  height: clamp(360px, 62vh, 720px);
  overflow: hidden;
  background: #111827;
  touch-action: none;
  cursor: grab;
  outline: none;
}
.viewport.bg-white { background: #ffffff; }
.viewport.bg-grey  { background: #6b7280; }
.viewport.panning { cursor: grabbing; }
.viewport.measuring { cursor: crosshair; }
.viewport:focus-visible { box-shadow: inset 0 0 0 3px var(--clr-focus); }
.viewport canvas,
.viewport img {
  position: absolute;
  top: 0; left: 0;
  user-select: none;
  -webkit-user-drag: none;
}
.viewport canvas { width: 100%; height: 100%; }
.viewport img { transform-origin: 0 0; image-rendering: auto; pointer-events: none; }
.viewport .empty-state {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #9ca3af;
  font-size: .95rem;
  text-align: center;
  padding: 1rem;
}
.viewport.bg-white .empty-state { color: #4b5563; }
.viewport .empty-state[hidden] { display: none; }

.statusbar {
  display: flex;
  flex-wrap: wrap;
  gap: .25rem 1.25rem;
  padding: .5rem .9rem;
  border-top: 1px solid var(--clr-border);
  background: var(--clr-surface-2);
  font-size: .8rem;
  color: var(--clr-text-muted);
  font-variant-numeric: tabular-nums;
  min-height: 2.2rem;
}
.statusbar strong { color: var(--clr-text); font-family: 'JetBrains Mono', monospace; font-weight: 600; }
.statusbar .measure-readout { color: var(--clr-primary); font-weight: 600; }

/* Side panel */
.side-panel {
  border-left: 1px solid var(--clr-border);
  background: var(--clr-surface);
  display: flex;
  flex-direction: column;
  min-width: 0;
  max-height: calc(clamp(360px, 62vh, 720px) + 92px);
}
.panel-block { padding: .9rem 1rem; border-bottom: 1px solid var(--clr-border); }
.panel-block:last-child { border-bottom: none; }
.panel-block h3 {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .5rem;
  font-size: .75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--clr-text-muted);
  margin-bottom: .6rem;
}
.panel-block h3 .link-btn {
  font-size: .75rem;
  text-transform: none;
  letter-spacing: 0;
  background: none;
  border: none;
  color: var(--clr-primary);
  font-weight: 600;
  padding: 0;
}
.panel-block h3 .link-btn:hover { text-decoration: underline; }
.layers-block { flex: 1; min-height: 0; overflow: auto; }
.layer-list { display: flex; flex-direction: column; gap: .1rem; }
.layer-item {
  display: flex;
  align-items: center;
  gap: .55rem;
  padding: .3rem .25rem;
  border-radius: var(--radius-sm);
  font-size: .85rem;
  cursor: pointer;
}
.layer-item:hover { background: var(--clr-surface-2); }
.layer-item input { width: 16px; height: 16px; accent-color: var(--clr-primary); cursor: pointer; flex-shrink: 0; }
.layer-swatch { width: 12px; height: 12px; border-radius: 3px; border: 1px solid rgba(0,0,0,.25); flex-shrink: 0; }
.layer-name { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.layer-count { font-size: .75rem; color: var(--clr-text-muted); font-variant-numeric: tabular-nums; }

.info-list { display: grid; grid-template-columns: auto minmax(0, 1fr); gap: .3rem .75rem; font-size: .82rem; }
.info-list dt { color: var(--clr-text-muted); }
.info-list dd { font-weight: 600; text-align: right; overflow-wrap: anywhere; font-variant-numeric: tabular-nums; }
.info-note { font-size: .78rem; color: var(--clr-text-muted); margin-top: .6rem; line-height: 1.5; }
.empty-note { font-size: .85rem; color: var(--clr-text-muted); }

/* =============================================
   REFERENCE SECTION (case descriptions)
   ============================================= */
.reference-section {
  padding: 3rem 0;
  background: var(--clr-surface-2);
  border-top: 1px solid var(--clr-border);
}
.reference-section h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: .5rem;
}
.reference-section .section-subtitle {
  color: var(--clr-text-muted);
  margin-bottom: 2rem;
}
.reference-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.25rem;
}
.ref-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.4rem;
  transition: box-shadow var(--transition), transform var(--transition);
}
.ref-card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.ref-card h3 { font-size: 1rem; font-weight: 600; margin-bottom: .35rem; }
.ref-card .example {
  font-family: 'JetBrains Mono', 'Courier New', monospace;
  font-size: .85rem;
  background: var(--clr-surface-2);
  color: var(--clr-primary);
  padding: .3rem .6rem;
  border-radius: var(--radius-sm);
  display: inline-block;
  margin-bottom: .5rem;
}
.ref-card p { font-size: .875rem; color: var(--clr-text-muted); }

/* =============================================
   ABOUT SECTION
   ============================================= */
#about {
  padding: 3.5rem 0;
}
.about-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}
.about-text h2 { font-size: 1.75rem; font-weight: 800; margin-bottom: 1rem; }
.about-text p { color: var(--clr-text-muted); line-height: 1.8; margin-bottom: .75rem; }
.feature-list { display: flex; flex-direction: column; gap: .65rem; margin-top: 1.25rem; }
.feature-item {
  display: flex;
  align-items: flex-start;
  gap: .75rem;
  font-size: .9rem;
}
.feature-icon {
  width: 30px; height: 30px; flex-shrink: 0;
  border-radius: 50%;
  background: var(--clr-primary-light);
  display: flex; align-items: center; justify-content: center;
  color: var(--clr-primary);
  font-size: 1rem;
  margin-top: .05rem;
}
.about-visual {
  background: var(--rm-hero-bg);
  border-radius: var(--radius-xl);
  padding: 2.5rem;
  color: #fff;
}
.demo-cases { display: flex; flex-direction: column; gap: .85rem; }
.demo-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(255,255,255,.12);
  border-radius: var(--radius-md);
  padding: .65rem 1rem;
  font-size: .88rem;
  backdrop-filter: blur(4px);
}
.demo-row .label { opacity: .8; font-weight: 500; }
.demo-row .value { font-weight: 700; font-family: 'JetBrains Mono', monospace; }

/* =============================================
   FOOTER
   ============================================= */
.site-footer {
  background: var(--clr-surface);
  border-top: 1px solid var(--clr-border);
  padding-top: 3rem;
  transition: background var(--transition);
}
.footer-inner {
  display: grid;
  grid-template-columns: 1.4fr 2fr;
  gap: 3rem;
  padding-bottom: 2.5rem;
}
.footer-brand .logo { margin-bottom: .75rem; }
.footer-tagline { font-size: .875rem; color: var(--clr-text-muted); max-width: 260px; line-height: 1.6; }
.footer-links { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
.footer-col h4 { font-size: .8rem; text-transform: uppercase; letter-spacing: 1px; color: var(--clr-text-muted); margin-bottom: .85rem; }
.footer-col li + li { margin-top: .45rem; }
.footer-col a { font-size: .875rem; color: var(--clr-text-muted); transition: color var(--transition); }
.footer-col a:hover { color: var(--clr-primary); text-decoration: none; }
.footer-bottom {
  border-top: 1px solid var(--clr-border);
  padding: 1.25rem 0;
  font-size: .8rem;
  color: var(--clr-text-muted);
}
.footer-bottom .container {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: .5rem;
}

/* =============================================
   RESPONSIVE
   ============================================= */
@media (max-width: 900px) {
  .field-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .viewer-layout { grid-template-columns: minmax(0, 1fr); }
  .side-panel { border-left: none; border-top: 1px solid var(--clr-border); max-height: none; }
}

@media (max-width: 768px) {
  .main-nav {
    display: none;
    position: fixed;
    inset: var(--header-h) 0 0;
    background: var(--clr-surface);
    padding: 1.5rem 1.25rem;
    z-index: 99;
    flex-direction: column;
    gap: .35rem;
    border-top: 1px solid var(--clr-border);
  }
  .main-nav.open { display: flex; }
  .main-nav ul { flex-direction: column; }
  .nav-link { font-size: 1.1rem; padding: .75rem 1rem; }
  .btn-mobile-menu { display: flex; }
  .about-inner { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; gap: 2rem; }
  .footer-links { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 480px) {
  .field-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-links { grid-template-columns: 1fr; }
  .action-bar { gap: .4rem; }
  .action-btn { padding: .45rem .75rem; font-size: .8rem; }
  .about-visual { padding: 1.5rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; scroll-behavior: auto !important; }
}

/* =============================================
   Shared romelmasagca.com tool theme (../shared/rm-tools.css)
   Maps this tool's variables onto the --rm-* tokens, light and dark.
   ============================================= */
:root, :root[data-theme="dark"] {
  --clr-primary:       var(--rm-primary);
  --clr-primary-dark:  var(--rm-primary-hover);
  --clr-primary-light: var(--rm-primary-soft);
  --clr-on-primary:    var(--rm-primary-ink);
  --clr-accent:        var(--rm-amber);
  --clr-focus:         var(--rm-primary);
  --clr-bg:            var(--rm-bg);
  --clr-surface:       var(--rm-surface);
  --clr-surface-2:     var(--rm-surface-2);
  --clr-border:        var(--rm-border);
  --clr-border-strong: var(--rm-muted);
  --clr-text:          var(--rm-text);
  --clr-text-muted:    var(--rm-muted);
  --clr-text-inverse:  var(--rm-bg);
  --radius-sm:  var(--rm-radius-sm);
  --radius-md:  var(--rm-radius);
  --radius-lg:  var(--rm-radius);
  --radius-xl:  var(--rm-radius-lg);
  --shadow-sm:  var(--rm-shadow-sm);
  --shadow-md:  var(--rm-shadow-md);
  --shadow-lg:  var(--rm-shadow-lg);
  --transition: var(--rm-ease);
}
html { scroll-padding-top: 80px; }
/* Hero: the shared blueprint band in both themes */
.hero.rm-hero { background: var(--rm-hero-bg); color: var(--rm-hero-ink); }
.hero.rm-hero h1 { color: var(--rm-hero-ink); -webkit-text-fill-color: currentColor; background: none; font-weight: 700; line-height: 1.1; }
.hero.rm-hero p { color: var(--rm-hero-muted); opacity: 1; }