/* wissen.css — Photon Flux Nutrients Knowledge / Wissen Pages
   Dark theme consistent with Photon Flux app design tokens.
   Accent: vibrant violet (#8b5cf6) + luminous teal (#22d3ee).
   No inline JavaScript.
   Inter font via Google Fonts with self-hosted fallback.
*/

/* ── Google Fonts Import (Inter) ──────────────────────────────────────── */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700&display=swap');

/* ── Self-hosted Font Faces (fallback if fonts are available locally) ── */

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('/wissen-assets/fonts/inter-latin-400.woff2') format('woff2');
}

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url('/wissen-assets/fonts/inter-latin-600.woff2') format('woff2');
}

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url('/wissen-assets/fonts/inter-latin-700.woff2') format('woff2');
}

/* ── Design Tokens ─────────────────────────────────────────────────────── */

:root {
  --bg:            #0b1220;
  --surface:       #101827;
  --surface-raise: #161d27;
  --elevated:      #1c2430;

  --accent:        #8b5cf6;
  --accent-hover:  #7c3aed;
  --accent-dim:    rgba(139, 92, 246, 0.12);
  --accent-glow:   rgba(139, 92, 246, 0.08);

  --teal:          #22d3ee;
  --teal-dim:      rgba(34, 211, 238, 0.12);

  --text-1:        #e8eef9;
  --text-2:        #9aa6bd;
  --text-3:        #4b5563;

  --border:        rgba(139, 92, 246, 0.10);
  --border-hover:  rgba(139, 92, 246, 0.25);
  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-mid:    rgba(255, 255, 255, 0.11);

  --gold:          #facc15;
  --shadow-glow:   0 0 40px rgba(139, 92, 246, 0.15);

  --sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  --r-sm:  4px;
  --r-md:  8px;
  --r-lg:  12px;
  --r-xl:  16px;

  --sp-xs: 0.25rem;
  --sp-sm: 0.5rem;
  --sp-md: 1rem;
  --sp-lg: 1.5rem;
  --sp-xl: 2rem;
  --sp-2xl: 3rem;
  --sp-3xl: 4rem;

  --max-w: 860px;
}

/* ── Reset ─────────────────────────────────────────────────────────────── */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
a, a:link, a:visited { color: inherit; text-decoration: none; }

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

body {
  background: var(--bg);
  color: var(--text-2);
  font-family: var(--sans);
  line-height: 1.78;
  min-height: 100vh;
}

::selection {
  background: rgba(139, 92, 246, 0.25);
  color: var(--text-1);
}

/* ── Skip Link ─────────────────────────────────────────────────────────── */

.skip-link {
  position: absolute;
  top: -100%;
  left: var(--sp-md);
  background: var(--accent);
  color: #fff;
  font-size: 0.85rem;
  font-weight: 600;
  padding: 8px 14px;
  border-radius: var(--r-sm);
  text-decoration: none;
  z-index: 200;
}
.skip-link:focus {
  top: var(--sp-md);
}

/* ── Header ────────────────────────────────────────────────────────────── */

header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11, 18, 32, 0.85);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: var(--sp-lg) var(--sp-xl);
}

.brand-link {
  color: var(--text-1);
  font-size: 1.1rem;
  font-weight: 700;
  text-decoration: none;
  letter-spacing: -0.02em;
}
.brand-link .brand-ai,
.brand-link .brand-accent {
  background: linear-gradient(135deg, var(--accent), var(--teal));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-links {
  display: flex;
  align-items: center;
  gap: var(--sp-lg);
}

.back-link {
  color: var(--text-2);
  text-decoration: none;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: color 0.2s;
}
.back-link:hover { color: var(--accent); }
.back-link svg { flex-shrink: 0; }

.lang-switch {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-3);
  text-decoration: none;
  padding: 4px 8px;
  border-radius: var(--r-sm);
  transition: color 0.2s;
}
.lang-switch:hover { color: var(--accent); }

/* ── Breadcrumb ────────────────────────────────────────────────────────── */

.breadcrumb {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: var(--sp-md) var(--sp-xl) 0;
}
.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  gap: 0;
  font-size: 0.82rem;
  color: var(--text-3);
}
.breadcrumb li::after {
  content: " / ";
  margin: 0 6px;
  color: var(--text-3);
}
.breadcrumb li:last-child::after { content: ""; }
.breadcrumb a {
  color: var(--text-2);
  text-decoration: none;
  transition: color 0.2s;
}
.breadcrumb a:hover { color: var(--accent); }
.breadcrumb [aria-current="page"] {
  color: var(--text-2);
}

/* ── Document Header ───────────────────────────────────────────────────── */

.doc-header {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: var(--sp-2xl) var(--sp-xl) var(--sp-lg);
}

.doc-category {
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--teal);
  margin-bottom: var(--sp-sm);
}

.doc-title {
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  font-weight: 700;
  color: var(--text-1);
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin-bottom: var(--sp-md);
}

.doc-subtitle {
  color: var(--text-2);
  max-width: 640px;
  margin-top: var(--sp-sm);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* ── Article figures (images) ──────────────────────────────────────────── */

.article-figure,
figure.article-figure {
  display: block;
  margin: var(--sp-2xl) auto;
  text-align: center;
  max-width: var(--max-w);
  padding: 0 var(--sp-xl);
}

.article-figure picture,
.article-figure img {
  display: block;
  margin: 0 auto;
  max-width: 100%;
  height: auto;
  border-radius: 10px;
}

.article-figure figcaption {
  margin-top: var(--sp-sm);
  font-size: 0.82rem;
  color: var(--text-3);
  text-align: center;
}

.article-meta {
  font-size: 0.82rem;
  color: var(--text-3);
}

/* ── Table of Contents ─────────────────────────────────────────────────── */

.toc {
  max-width: var(--max-w);
  margin: 0 auto var(--sp-2xl);
  padding: 0 var(--sp-xl);
}

.toc-title,
.toc-heading {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-3);
  margin-bottom: var(--sp-sm);
}

.toc-list,
.toc ol,
.toc ul {
  list-style: none;
  border-left: 2px solid var(--border);
  padding-left: var(--sp-lg);
}
.toc-list li,
.toc ol li,
.toc ul li { margin-bottom: 4px; }

.toc-list a,
.toc ol a,
.toc ul a,
.toc-link {
  color: var(--text-2);
  text-decoration: none;
  font-size: 0.88rem;
  transition: color 0.2s;
}
.toc-list a:hover,
.toc ol a:hover,
.toc ul a:hover,
.toc-link:hover { color: var(--accent); }

/* ── Content Area ──────────────────────────────────────────────────────── */

.doc-section {
  max-width: var(--max-w);
  margin: 0 auto var(--sp-2xl);
  padding: 0 var(--sp-xl);
}

.doc-section h2 {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-1);
  margin-bottom: var(--sp-md);
  padding-bottom: var(--sp-sm);
  border-bottom: 1px solid var(--border-subtle);
  letter-spacing: -0.01em;
  scroll-margin-top: 80px;
}

.doc-section h3 {
  font-size: 1.08rem;
  font-weight: 600;
  color: var(--text-1);
  margin-top: var(--sp-xl);
  margin-bottom: var(--sp-sm);
  scroll-margin-top: 80px;
}

.doc-section p {
  margin-bottom: var(--sp-md);
  line-height: 1.82;
}

.doc-section ul,
.doc-section ol {
  margin-bottom: var(--sp-md);
  padding-left: var(--sp-xl);
}
.doc-section li {
  margin-bottom: 6px;
}

.doc-section strong {
  color: var(--text-1);
  font-weight: 600;
}

.doc-section a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s;
}
.doc-section a:hover {
  border-bottom-color: var(--accent);
}

/* ── Tables ────────────────────────────────────────────────────────────── */

.value-table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: var(--sp-lg);
  font-size: 0.9rem;
}

.value-table thead {
  background: var(--surface);
}
.value-table th {
  color: var(--text-1);
  font-weight: 600;
  text-align: left;
  padding: var(--sp-sm) var(--sp-md);
  border-bottom: 2px solid var(--border-mid);
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.value-table td {
  padding: var(--sp-sm) var(--sp-md);
  border-bottom: 1px solid var(--border-subtle);
  vertical-align: top;
}

.value-table tbody tr:hover {
  background: var(--accent-glow);
}

/* ── Info / Callout / Warning Boxes ────────────────────────────────────── */

.info-box,
.callout-box,
.warning-box {
  border-radius: var(--r-md);
  padding: var(--sp-md) var(--sp-lg);
  margin-bottom: var(--sp-lg);
  font-size: 0.92rem;
  line-height: 1.7;
}

.info-box {
  background: var(--accent-dim);
  border-left: 3px solid var(--accent);
  color: var(--text-2);
  box-shadow: inset 0 0 20px rgba(139, 92, 246, 0.03);
}
.info-box strong { color: var(--accent); }

.callout-box {
  background: var(--teal-dim);
  border-left: 3px solid var(--teal);
  color: var(--text-2);
}
.callout-box strong { color: var(--teal); }

.warning-box {
  background: rgba(248, 81, 73, 0.08);
  border-left: 3px solid #F85149;
  color: var(--text-2);
}
.warning-box strong { color: #F85149; }

/* ── FAQ Accordion (CSS-only via details/summary) ──────────────────────── */

.faq-section {
  max-width: var(--max-w);
  margin: 0 auto var(--sp-2xl);
  padding: 0 var(--sp-xl);
}

.faq-section > h2 {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-1);
  margin-bottom: var(--sp-lg);
  padding-bottom: var(--sp-sm);
  border-bottom: 1px solid var(--border-subtle);
}

.faq-item {
  border: 1px solid var(--border-subtle);
  border-radius: var(--r-md);
  margin-bottom: var(--sp-sm);
  overflow: hidden;
  transition: border-color 0.2s;
}
.faq-item:hover {
  border-color: var(--border-mid);
}
.faq-item[open] {
  border-color: var(--border-hover);
}

.faq-item summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text-1);
  padding: var(--sp-md) var(--sp-lg);
  background: var(--surface);
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-md);
  transition: background 0.2s;
}
.faq-item summary:hover {
  background: var(--surface-raise);
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::marker { display: none; }

.faq-item summary::after {
  content: "+";
  font-size: 1.2rem;
  color: var(--text-3);
  flex-shrink: 0;
  transition: color 0.2s;
}
.faq-item[open] summary::after {
  content: "\2212";
  color: var(--accent);
}

.faq-answer {
  padding: var(--sp-md) var(--sp-lg) var(--sp-lg);
  border-top: 1px solid var(--border-subtle);
}
.faq-answer p { margin-bottom: var(--sp-sm); }
.faq-answer p:last-child { margin-bottom: 0; }

/* ── Step List (HowTo) ─────────────────────────────────────────────────── */

.step-list {
  list-style: none;
  counter-reset: step-counter;
  padding-left: 0;
  margin-bottom: var(--sp-lg);
}

.step-list li {
  counter-increment: step-counter;
  position: relative;
  padding-left: 3rem;
  margin-bottom: var(--sp-lg);
  min-height: 2rem;
}
.step-list li::before {
  content: counter(step-counter);
  position: absolute;
  left: 0;
  top: 0;
  width: 2rem;
  height: 2rem;
  background: var(--accent-dim);
  border: 1px solid var(--accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--accent);
}
.step-list li strong {
  display: block;
  color: var(--text-1);
  font-weight: 600;
  margin-bottom: 4px;
}

/* ── CTA Banner ────────────────────────────────────────────────────────── */

.cta-banner {
  max-width: var(--max-w);
  margin: 0 auto var(--sp-2xl);
  padding: var(--sp-2xl) var(--sp-xl);
  text-align: center;
}

.cta-banner-inner {
  background: linear-gradient(135deg, var(--surface) 0%, var(--surface-raise) 100%);
  border: 1px solid var(--border-hover);
  border-radius: var(--r-xl);
  padding: var(--sp-2xl) var(--sp-xl);
  box-shadow: 0 0 60px rgba(139, 92, 246, 0.06);
}

.cta-eyebrow {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--yellow, #facc15);
  margin-bottom: var(--sp-sm) !important;
}

.cta-banner h2 {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-1);
  margin-bottom: var(--sp-md);
}

.cta-banner p {
  color: var(--text-2);
  margin-bottom: var(--sp-lg);
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.7;
}

.cta-banner .mockup-list {
  list-style: none;
  text-align: left;
  max-width: 520px;
  margin: 0 auto var(--sp-xl);
  padding: 0;
}
.cta-banner .mockup-list li {
  padding: var(--sp-sm) 0;
  padding-left: var(--sp-lg);
  position: relative;
  color: var(--text-2);
  font-size: 0.92rem;
  line-height: 1.65;
}
.cta-banner .mockup-list li::before {
  content: "\2713";
  position: absolute;
  left: 0;
  color: var(--teal);
  font-weight: 700;
}

.btn-primary {
  display: inline-block;
  background: linear-gradient(135deg, var(--accent), #6d28d9);
  color: #fff;
  font-size: 0.95rem;
  font-weight: 600;
  padding: 12px 28px;
  border-radius: var(--r-lg);
  text-decoration: none;
  transition: box-shadow 0.2s, transform 0.2s;
}
.btn-primary:hover {
  box-shadow: 0 0 24px rgba(139, 92, 246, 0.4);
  transform: translateY(-1px);
}

/* ── Cross-Links ───────────────────────────────────────────────────────── */

.cross-links {
  max-width: var(--max-w);
  margin: 0 auto var(--sp-2xl);
  padding: 0 var(--sp-xl);
}

.cross-links h2 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-1);
  margin-bottom: var(--sp-md);
}

.cross-links-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--sp-md);
}

.cross-link-card {
  display: block;
  position: relative;
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--r-md);
  padding: var(--sp-md) var(--sp-lg);
  text-decoration: none;
  transition: border-color 0.2s, background 0.2s;
}
.cross-link-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--teal));
  opacity: 0;
  transition: opacity 0.25s;
}
.cross-link-card:hover {
  border-color: var(--border-hover);
  background: var(--surface-raise);
}
.cross-link-card:hover::before {
  opacity: 1;
}
.cross-link-card .card-title {
  color: var(--text-1);
  font-weight: 600;
  font-size: 0.92rem;
  margin-bottom: 4px;
}
.cross-link-card .card-desc {
  color: var(--text-3);
  font-size: 0.82rem;
  line-height: 1.5;
}

/* ── Hub Page (Article List) ───────────────────────────────────────────── */

.hub-section {
  max-width: var(--max-w);
  margin: 0 auto var(--sp-xl);
  padding: 0 var(--sp-xl);
}

.hub-section-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-1);
  margin-bottom: var(--sp-lg);
  padding-bottom: var(--sp-sm);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
}

.hub-section-icon {
  font-size: 1rem;
}

.hub-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--sp-lg);
}

.hub-grid-featured {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--sp-md);
}

.hub-card {
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--r-lg);
  padding: var(--sp-lg);
  text-decoration: none;
  transition: border-color 0.25s, transform 0.25s, box-shadow 0.25s;
}
.hub-card:hover {
  border-color: var(--border-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3), var(--shadow-glow);
}
.hub-card .hub-card-cluster {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--teal);
  margin-bottom: var(--sp-sm);
}
.hub-card .hub-card-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-1);
  margin-bottom: var(--sp-sm);
  line-height: 1.35;
}
.hub-card .hub-card-desc {
  font-size: 0.88rem;
  color: var(--text-2);
  line-height: 1.6;
  flex-grow: 1;
}
.hub-card .hub-card-link {
  margin-top: var(--sp-md);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent);
}

/* Featured tool/calculator cards */
.hub-card-featured {
  border-color: var(--accent-dim);
  background: linear-gradient(145deg, var(--surface) 0%, rgba(139, 92, 246, 0.04) 100%);
}
.hub-card-featured:hover {
  border-color: var(--accent);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3), 0 0 40px rgba(139, 92, 246, 0.12);
}
.hub-card-featured .hub-card-cluster {
  color: var(--accent);
}
.hub-card-featured .hub-card-link {
  color: var(--teal);
}

/* ── Footer ────────────────────────────────────────────────────────────── */

footer {
  border-top: 1px solid var(--border-subtle);
  margin-top: var(--sp-3xl);
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: var(--sp-xl) var(--sp-xl);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-md);
}

.footer-brand {
  color: var(--text-1);
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
}
.footer-brand .brand-ai,
.footer-brand .brand-accent {
  background: linear-gradient(135deg, var(--accent), var(--teal));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer-links {
  display: flex;
  list-style: none;
  gap: var(--sp-lg);
}
.footer-links a {
  color: var(--text-3);
  text-decoration: none;
  font-size: 0.82rem;
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--text-2); }

.footer-copy {
  color: var(--text-3);
  font-size: 0.78rem;
}

/* ── Responsive ────────────────────────────────────────────────────────── */

@media (max-width: 640px) {
  .header-inner { padding: var(--sp-md); }
  .doc-header   { padding: var(--sp-xl) var(--sp-md) var(--sp-md); }
  .breadcrumb   { padding: var(--sp-sm) var(--sp-md) 0; }
  .toc          { padding: 0 var(--sp-md); }
  .doc-section  { padding: 0 var(--sp-md); }
  .faq-section  { padding: 0 var(--sp-md); }
  .cta-banner   { padding: var(--sp-xl) var(--sp-md); }
  .cross-links  { padding: 0 var(--sp-md); }
  .hub-section  { padding: 0 var(--sp-md); }
  .hub-grid     { grid-template-columns: 1fr; }
  .hub-grid-featured { grid-template-columns: 1fr; }
  .footer-inner { padding: var(--sp-lg) var(--sp-md); flex-direction: column; text-align: center; }

  .value-table { font-size: 0.82rem; }
  .value-table th,
  .value-table td { padding: var(--sp-xs) var(--sp-sm); }

  .cross-links-grid { grid-template-columns: 1fr; }
}

/* ── VPD Calculator ────────────────────────────────────────────────────── */

.vpd-calc-wrap {
  background: var(--elevated);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: var(--sp-lg);
  margin: var(--sp-lg) 0;
}

.vpd-calc-wrap h3 {
  margin: 0 0 var(--sp-md);
  font-size: 1.05rem;
  color: var(--text-1);
}

.vpd-calc-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-md);
  margin-bottom: var(--sp-md);
}

.vpd-calc-field label {
  display: block;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.35rem;
}

.vpd-calc-field input[type="number"] {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.5rem 0.75rem;
  color: var(--text-1);
  font-size: 1rem;
  font-family: inherit;
  box-sizing: border-box;
  -moz-appearance: textfield;
}

.vpd-calc-field input[type="number"]::-webkit-inner-spin-button,
.vpd-calc-field input[type="number"]::-webkit-outer-spin-button {
  opacity: 1;
}

.vpd-calc-field input[type="number"]:focus {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
  border-color: transparent;
}

.vpd-calc-field .field-hint {
  font-size: 0.72rem;
  color: var(--text-3);
  margin-top: 0.25rem;
}

.vpd-calc-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, var(--accent), #6d28d9);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 0.6rem 1.4rem;
  font-size: 0.9rem;
  font-weight: 700;
  cursor: pointer;
  font-family: inherit;
  transition: opacity 0.15s;
}

.vpd-calc-btn:hover { opacity: 0.88; }

.vpd-calc-result {
  margin-top: var(--sp-md);
  padding: var(--sp-sm) var(--sp-md);
  border-radius: 8px;
  display: flex;
  align-items: center;
  gap: var(--sp-md);
  font-size: 0.9rem;
}

.vpd-calc-result[hidden] { display: none; }

.vpd-calc-result.zone-ok {
  background: rgba(139, 92, 246, 0.1);
  border: 1px solid rgba(139, 92, 246, 0.25);
  color: var(--text-1);
}

.vpd-calc-result.zone-low {
  background: rgba(34, 211, 238, 0.1);
  border: 1px solid rgba(34, 211, 238, 0.25);
  color: var(--text-1);
}

.vpd-calc-result.zone-high {
  background: rgba(255, 123, 114, 0.1);
  border: 1px solid rgba(255, 123, 114, 0.25);
  color: var(--text-1);
}

.vpd-result-value {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--accent);
  white-space: nowrap;
  min-width: 6rem;
}

.vpd-result-zone {
  color: var(--text-2);
  line-height: 1.4;
}

@media (max-width: 640px) {
  .vpd-calc-grid { grid-template-columns: 1fr 1fr; }
  .vpd-calc-result { flex-direction: column; align-items: flex-start; gap: var(--sp-xs); }
}

@media (max-width: 400px) {
  .vpd-calc-grid { grid-template-columns: 1fr; }
}

/* ── Shared Calculator Styles (EC, Light, Feed Schedule) ──────────────── */

.calc-wrap {
  background: var(--elevated);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: var(--sp-lg);
  margin: var(--sp-lg) 0;
}

.calc-wrap h3 {
  margin: 0 0 var(--sp-md);
  font-size: 1.05rem;
  color: var(--text-1);
}

.calc-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-md);
  margin-bottom: var(--sp-md);
}

.calc-grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--sp-md);
  margin-bottom: var(--sp-md);
}

.calc-field label {
  display: block;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.35rem;
}

.calc-field input[type="number"],
.calc-field select {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.5rem 0.75rem;
  color: var(--text-1);
  font-size: 1rem;
  font-family: inherit;
  box-sizing: border-box;
}

.calc-field select {
  appearance: none;
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%239aa6bd' fill='none' stroke-width='1.5'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  padding-right: 2rem;
}

.calc-field input[type="number"]:focus,
.calc-field select:focus {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
  border-color: transparent;
}

.calc-field .field-hint {
  font-size: 0.72rem;
  color: var(--text-3);
  margin-top: 0.25rem;
}

.calc-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, var(--accent), #6d28d9);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 0.6rem 1.4rem;
  font-size: 0.9rem;
  font-weight: 700;
  cursor: pointer;
  font-family: inherit;
  transition: opacity 0.15s;
}

.calc-btn:hover { opacity: 0.88; }

.calc-result {
  margin-top: var(--sp-md);
  padding: var(--sp-md);
  border-radius: 8px;
}

.calc-result[hidden] { display: none; }

.calc-result.zone-ok {
  background: rgba(139, 92, 246, 0.08);
  border: 1px solid rgba(139, 92, 246, 0.2);
}

.calc-result.zone-low {
  background: rgba(34, 211, 238, 0.08);
  border: 1px solid rgba(34, 211, 238, 0.2);
}

.calc-result.zone-high {
  background: rgba(255, 123, 114, 0.08);
  border: 1px solid rgba(255, 123, 114, 0.2);
}

/* ── EC / Light result cards ──────────────────────────────────────────── */

.ec-result-header {
  display: flex;
  align-items: center;
  gap: var(--sp-sm);
  margin-bottom: var(--sp-sm);
}

.ec-result-stage {
  font-weight: 700;
  color: var(--accent);
  font-size: 1rem;
}

.ec-result-medium {
  color: var(--text-3);
  font-size: 0.82rem;
}

.ec-result-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-sm);
}

.ec-result-card {
  background: rgba(0, 0, 0, 0.2);
  border-radius: 8px;
  padding: var(--sp-sm);
  text-align: center;
}

.ec-result-label {
  display: block;
  font-size: 0.72rem;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 0.2rem;
}

.ec-result-value {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-1);
}

.ec-result-note {
  margin-top: var(--sp-sm);
  font-size: 0.82rem;
  color: var(--text-2);
}

/* ── Feed schedule table ──────────────────────────────────────────────── */

.feed-table-wrap {
  overflow-x: auto;
  margin-top: var(--sp-sm);
  -webkit-overflow-scrolling: touch;
}

.feed-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
}

.feed-table th {
  text-align: left;
  font-size: 0.72rem;
  color: var(--text-3);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0.4rem 0.6rem;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

.feed-table td {
  padding: 0.4rem 0.6rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.03);
  color: var(--text-2);
}

.feed-week-num {
  font-weight: 700;
  color: var(--text-1);
  text-align: center;
  min-width: 2.5rem;
}

.feed-ec-val {
  font-weight: 600;
  color: var(--accent);
  white-space: nowrap;
}

.feed-bar-wrap {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.feed-bar {
  height: 6px;
  border-radius: 3px;
  min-width: 4px;
  transition: width 0.2s ease;
}

.feed-bar-label {
  font-size: 0.72rem;
  color: var(--text-3);
  white-space: nowrap;
  min-width: 2.2rem;
}

@media (max-width: 640px) {
  .calc-grid { grid-template-columns: 1fr 1fr; }
  .calc-grid-2 { grid-template-columns: 1fr; }
  .ec-result-grid { grid-template-columns: 1fr; }
}

@media (max-width: 400px) {
  .calc-grid { grid-template-columns: 1fr; }
}

/* ── Focus Visible ─────────────────────────────────────────────────────── */

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ── Reduced Motion ────────────────────────────────────────────────────── */

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}