/* ============================================
   Julius Wittenberg Ghostwriting
   LaTeX Paper Style — style.css
   ============================================ */

@font-face { font-family: 'Latin Modern Roman'; src: url('https://cdn.jsdelivr.net/gh/aaaakshat/cm-web-fonts@latest/fonts/Latin-Modern-Roman/lmroman10-regular.woff2') format('woff2'); font-weight: 400; font-style: normal; font-display: swap; }
@font-face { font-family: 'Latin Modern Roman'; src: url('https://cdn.jsdelivr.net/gh/aaaakshat/cm-web-fonts@latest/fonts/Latin-Modern-Roman/lmroman10-bold.woff2') format('woff2'); font-weight: 700; font-style: normal; font-display: swap; }
@font-face { font-family: 'Latin Modern Roman'; src: url('https://cdn.jsdelivr.net/gh/aaaakshat/cm-web-fonts@latest/fonts/Latin-Modern-Roman/lmroman10-italic.woff2') format('woff2'); font-weight: 400; font-style: italic; font-display: swap; }
@font-face { font-family: 'Latin Modern Roman'; src: url('https://cdn.jsdelivr.net/gh/aaaakshat/cm-web-fonts@latest/fonts/Latin-Modern-Roman/lmroman10-bolditalic.woff2') format('woff2'); font-weight: 700; font-style: italic; font-display: swap; }
@font-face { font-family: 'Latin Modern Mono'; src: url('https://cdn.jsdelivr.net/gh/aaaakshat/cm-web-fonts@latest/fonts/Latin-Modern-Mono/lmmono10-regular.woff2') format('woff2'); font-weight: 400; font-style: normal; font-display: swap; }

:root {
    --font-serif: 'Latin Modern Roman', 'Computer Modern', Georgia, 'Times New Roman', serif;
    --font-mono: 'Latin Modern Mono', 'Courier New', monospace;
    --color-bg: #fefefe; --color-paper: #ffffff; --color-text: #1a1a1a;
    --color-text-secondary: #444; --color-text-muted: #666;
    --color-accent: #8b0000; --color-link: #00529B;
    --color-rule: #333; --color-rule-light: #ccc;
    --color-highlight: #fffde7; --color-shadow: rgba(0,0,0,0.08);
    --page-max-width: 850px; --page-padding-x: 72px; --page-padding-y: 60px;
    --fs-title: 24.88pt; --fs-author: 14.4pt; --fs-section: 17.28pt;
    --fs-subsection: 14.4pt; --fs-body: 12pt; --fs-small: 10pt;
    --fs-footnote: 9pt; --fs-abstract: 11pt;
    --lh-body: 1.45; --lh-heading: 1.2;
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: var(--font-serif); font-size: var(--fs-body); line-height: var(--lh-body); color: var(--color-text); background: var(--color-bg); text-rendering: optimizeLegibility; -webkit-font-smoothing: antialiased; hyphens: auto; -webkit-hyphens: auto; }

/* === PAPER === */
.paper { max-width: var(--page-max-width); margin: 0 auto; background: var(--color-paper); padding: var(--page-padding-y) var(--page-padding-x); min-height: 100vh; position: relative; }
@media (min-width: 920px) {
    body { background: #e8e8e8; padding: 40px 0; }
    .paper { box-shadow: 0 2px 20px var(--color-shadow), 0 0 1px rgba(0,0,0,0.1); min-height: auto; margin-bottom: 40px; }
}

/* === NAV === */
.paper-nav { position: fixed; top: 0; left: 0; right: 0; z-index: 100; background: rgba(254,254,254,0.92); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); border-bottom: 0.5pt solid var(--color-rule-light); font-size: var(--fs-small); transition: box-shadow 0.3s; }
.paper-nav.scrolled { box-shadow: 0 1px 8px rgba(0,0,0,0.06); }
.nav-inner { max-width: var(--page-max-width); margin: 0 auto; padding: 10px var(--page-padding-x); display: flex; justify-content: space-between; align-items: center; }
.nav-brand { font-variant: small-caps; font-size: var(--fs-body); letter-spacing: 0.03em; color: var(--color-text); text-decoration: none; white-space: nowrap; }
.nav-links { display: flex; gap: 14px; list-style: none; align-items: center; hyphens: none; }
.nav-links a { color: var(--color-text-secondary); text-decoration: none; font-size: var(--fs-small); transition: color 0.2s; hyphens: none; white-space: nowrap; }
.nav-links a:hover { color: var(--color-accent); }
.nav-cta { display: inline-block; padding: 6pt 14pt; font-family: var(--font-serif); font-size: var(--fs-footnote); font-variant: small-caps; letter-spacing: 0.04em; color: #fff !important; background: var(--color-text); text-decoration: none !important; transition: background 0.2s; }
.nav-cta:hover { background: var(--color-accent); color: #fff !important; }
.nav-wa { font-family: var(--font-mono); font-size: var(--fs-footnote); }
.nav-hamburger { display: none; background: none; border: none; cursor: pointer; width: 28px; height: 20px; position: relative; }
.nav-hamburger span { display: block; width: 100%; height: 1.5px; background: var(--color-text); position: absolute; left: 0; transition: all 0.3s; }
.nav-hamburger span:nth-child(1) { top: 0; }
.nav-hamburger span:nth-child(2) { top: 50%; transform: translateY(-50%); }
.nav-hamburger span:nth-child(3) { bottom: 0; }
.nav-hamburger.active span:nth-child(1) { top: 50%; transform: translateY(-50%) rotate(45deg); }
.nav-hamburger.active span:nth-child(2) { opacity: 0; }
.nav-hamburger.active span:nth-child(3) { bottom: 50%; transform: translateY(50%) rotate(-45deg); }

/* === BREADCRUMBS === */
.breadcrumbs { font-size: var(--fs-footnote); color: var(--color-text-muted); padding: 66px 0 0; margin-bottom: -30px; }
.breadcrumbs a { color: var(--color-text-muted); text-decoration: none; }
.breadcrumbs a:hover { color: var(--color-accent); text-decoration: underline; }

/* === TITLE === */
.title-block { text-align: center; padding-top: 60px; margin-bottom: 24pt; }
.document-class { font-family: var(--font-mono); font-size: var(--fs-footnote); color: var(--color-text-muted); margin-bottom: 18pt; }
.document-class .cmd { color: var(--color-accent); }
.paper-title { font-size: var(--fs-title); font-weight: 700; line-height: var(--lh-heading); margin-bottom: 12pt; letter-spacing: -0.01em; }
.paper-subtitle { font-size: var(--fs-subsection); font-weight: 400; font-style: italic; color: var(--color-text-secondary); margin-bottom: 16pt; line-height: 1.35; }
.capacity-hint { font-family: var(--font-mono); font-size: var(--fs-footnote); color: var(--color-accent); letter-spacing: 0.02em; margin-bottom: 18pt; }
.hero-stats { display: flex; justify-content: center; gap: 36px; margin: 8pt 0 18pt; flex-wrap: wrap; }
.hero-stat { text-align: center; }
.hero-stat-number { font-size: 28pt; font-weight: 700; font-style: italic; line-height: 1; display: block; }
.hero-stat-label { font-size: var(--fs-footnote); color: var(--color-text-muted); font-variant: small-caps; letter-spacing: 0.04em; margin-top: 3pt; display: block; }
.hero-stat-divider { color: var(--color-rule-light); font-size: 28pt; font-weight: 100; line-height: 1; align-self: center; user-select: none; }
.paper-author-line { font-size: var(--fs-author); font-variant: small-caps; letter-spacing: 0.04em; margin-bottom: 4pt; }
.paper-affiliation { font-size: var(--fs-small); font-style: italic; color: var(--color-text-secondary); margin-bottom: 4pt; }
.paper-email { font-family: var(--font-mono); font-size: var(--fs-small); color: var(--color-link); text-decoration: none; }
.paper-email:hover { text-decoration: underline; }
.title-rule { border: none; border-top: 1pt solid var(--color-rule); margin: 22pt auto; width: 100%; }
.title-rule-light { border: none; border-top: 0.5pt solid var(--color-rule-light); margin: 22pt auto; width: 100%; }

/* === ABSTRACT === */
.abstract-block { margin: 0 40px 18pt; }
.abstract-heading { font-size: var(--fs-body); font-weight: 700; text-align: center; margin-bottom: 8pt; }
.abstract-text { font-size: var(--fs-abstract); line-height: 1.5; text-align: justify; hyphens: auto; }
.keywords-block { margin: 10pt 40px 0; font-size: var(--fs-small); }
.keywords-block strong { font-style: italic; }

/* === HERO CTA === */
.hero-cta { text-align: center; margin: 22pt 0 8pt; padding: 14pt 0; border-top: 0.5pt solid var(--color-rule-light); border-bottom: 0.5pt solid var(--color-rule-light); }
.hero-cta-text { font-size: var(--fs-small); color: var(--color-text-secondary); margin-bottom: 10pt; font-style: italic; text-align: center !important; text-indent: 0 !important; }

/* === SECTIONS === */
.section-title { font-size: var(--fs-section); font-weight: 700; line-height: var(--lh-heading); margin-top: 28pt; margin-bottom: 10pt; scroll-margin-top: 60px; }
.section-number { margin-right: 10px; }
.subsection-title { font-size: var(--fs-subsection); font-weight: 700; line-height: var(--lh-heading); margin-top: 20pt; margin-bottom: 8pt; scroll-margin-top: 60px; }

/* === BODY TEXT === */
.paper p { text-align: justify; margin-bottom: 8pt; hyphens: auto; text-indent: 0; }
.paper p + p { text-indent: 1.5em; }
.paper .no-indent { text-indent: 0 !important; }
.paper a { color: var(--color-link); text-decoration: none; }
.paper a:hover { text-decoration: underline; }

/* === AUTHOR BIO === */
.author-bio { display: flex; gap: 24pt; margin: 16pt 0 8pt; align-items: flex-start; }
.author-photo { width: 120px; height: 150px; flex-shrink: 0; border: 0.5pt solid var(--color-rule-light); background: #f0f0f0; display: flex; align-items: center; justify-content: center; overflow: hidden; }
.author-photo img { width: 100%; height: 100%; object-fit: cover; filter: grayscale(100%); transition: filter 0.4s; }
.author-photo img:hover { filter: grayscale(0%); }
.author-photo-placeholder { font-size: var(--fs-footnote); color: var(--color-text-muted); text-align: center; font-style: italic; padding: 8px; }
.author-bio-text { flex: 1; font-size: var(--fs-small); line-height: 1.5; }
.author-bio-text p { font-size: var(--fs-small); text-align: justify; margin-bottom: 6pt; }
.author-bio-facts { display: flex; gap: 20pt; margin-top: 8pt; flex-wrap: wrap; }
.author-bio-fact { font-size: var(--fs-footnote); color: var(--color-text-muted); }
.author-bio-fact strong { color: var(--color-text); font-weight: 700; }

/* === ENVIRONMENTS === */
.theorem-env { margin: 16pt 0; padding: 12pt 16pt; border-left: 2pt solid var(--color-rule); background: var(--color-highlight); }
.theorem-env .env-label { font-weight: 700; font-style: italic; margin-bottom: 4pt; display: block; }
.definition-env { margin: 16pt 0; padding: 12pt 16pt; border-left: 2pt solid var(--color-accent); }
.definition-env .env-label { font-weight: 700; font-variant: small-caps; margin-bottom: 4pt; display: block; color: var(--color-accent); }
.proposition-env { margin: 18pt 0; padding: 16pt 20pt; border: 1pt solid var(--color-rule); background: #fafafa; }
.proposition-env .env-label { font-weight: 700; font-variant: small-caps; letter-spacing: 0.03em; margin-bottom: 8pt; display: block; }
.proposition-list { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: 1fr 1fr; gap: 6pt 20pt; }
.proposition-list li { font-size: var(--fs-small); padding-left: 16px; position: relative; text-align: left; }
.proposition-list li::before { content: '✓'; position: absolute; left: 0; color: var(--color-accent); font-weight: 700; }
.lemma-grid { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 16pt; margin: 16pt 0; }
.lemma-env { padding: 14pt 16pt; border: 0.5pt solid var(--color-rule-light); background: #fdfdfd; }
.lemma-env .env-label { font-weight: 700; font-style: italic; font-size: var(--fs-small); margin-bottom: 6pt; display: block; color: var(--color-accent); }
.lemma-env p { font-size: var(--fs-small); text-align: left; margin-bottom: 0; line-height: 1.45; }

/* === TABLES === */
.latex-table-wrapper { margin: 18pt 0; text-align: center; overflow-x: auto; }
.latex-table { border-collapse: collapse; margin: 0 auto; font-size: var(--fs-body); width: 100%; }
.latex-table thead { border-top: 2pt solid var(--color-rule); border-bottom: 1pt solid var(--color-rule); }
.latex-table thead th { padding: 8pt 10pt; font-weight: 700; text-align: left; font-size: var(--fs-small); }
.latex-table tbody { border-bottom: 2pt solid var(--color-rule); }
.latex-table tbody td { padding: 6pt 10pt; text-align: left; vertical-align: top; }
.latex-table tbody tr { cursor: pointer; transition: background 0.15s; }
.latex-table tbody tr:hover { background: var(--color-highlight); }
.price-col { font-weight: 700; white-space: nowrap; }
.express-yes { color: var(--color-accent); font-weight: 700; font-size: var(--fs-small); }
.express-no { color: var(--color-text-muted); font-size: var(--fs-small); }
.table-caption { font-size: var(--fs-small); margin-top: 8pt; color: var(--color-text-secondary); }
.table-caption .caption-label { font-weight: 700; }

/* === CALCULATOR === */
.calculator-env { margin: 22pt 0; padding: 20pt 24pt; border: 1pt solid var(--color-rule); background: #fafafa; }
.calculator-env .env-label { font-weight: 700; font-variant: small-caps; letter-spacing: 0.03em; margin-bottom: 4pt; display: block; }
.calculator-env .env-sublabel { font-size: var(--fs-small); font-style: italic; color: var(--color-text-muted); margin-bottom: 14pt; display: block; }
.calc-grid { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 14pt; margin-bottom: 16pt; }
.calc-field label { display: block; font-size: var(--fs-footnote); font-variant: small-caps; letter-spacing: 0.03em; color: var(--color-text-secondary); margin-bottom: 4pt; }
.calc-field select, .calc-field input { width: 100%; font-family: var(--font-serif); font-size: var(--fs-small); padding: 7pt 10pt; border: 0.5pt solid var(--color-rule-light); background: var(--color-paper); color: var(--color-text); }
.calc-field select:focus, .calc-field input:focus { outline: none; border-color: var(--color-accent); }
.calc-result { text-align: center; padding: 14pt 0; border-top: 0.5pt solid var(--color-rule-light); }
.calc-result-equation { font-size: 18pt; font-style: italic; margin-bottom: 4pt; }
.calc-result-equation .calc-price { font-size: 24pt; font-weight: 700; }
.calc-result-note { font-size: var(--fs-footnote); color: var(--color-text-muted); font-style: italic; }
.calc-cta { text-align: center; margin-top: 12pt; }

/* === PROCESS === */
.figure-env { margin: 20pt 0; text-align: center; }
.figure-caption { font-size: var(--fs-small); margin-top: 8pt; color: var(--color-text-secondary); }
.figure-caption .caption-label { font-weight: 700; }
.process-flow { display: flex; align-items: center; justify-content: center; gap: 0; margin: 20pt 0; flex-wrap: wrap; }
.process-step { text-align: center; flex: 1; min-width: 100px; padding: 10pt 4pt; }
.process-step .step-number { display: inline-flex; align-items: center; justify-content: center; width: 26pt; height: 26pt; border: 1.5pt solid var(--color-rule); border-radius: 50%; font-size: var(--fs-small); font-weight: 700; margin-bottom: 5pt; }
.process-step .step-label { display: block; font-size: var(--fs-small); font-variant: small-caps; letter-spacing: 0.02em; }
.process-step .step-desc { display: block; font-size: var(--fs-footnote); color: var(--color-text-muted); font-style: italic; margin-top: 2pt; }
.process-arrow { font-size: 14pt; color: var(--color-text-muted); flex-shrink: 0; margin: 0 -4px; }

/* === REVIEWS === */
.review-block { margin: 14pt 0; padding: 12pt 16pt; border-left: 2pt solid var(--color-rule-light); font-style: italic; }
.review-attribution { font-style: normal; font-size: var(--fs-small); color: var(--color-text-muted); margin-top: 6pt; text-indent: 0 !important; display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.review-grade { display: inline-block; background: var(--color-highlight); border: 0.5pt solid #ddd; padding: 1pt 6pt; font-weight: 700; font-size: var(--fs-footnote); }
.review-verified { display: inline-flex; align-items: center; gap: 3px; font-size: var(--fs-footnote); color: #2e7d32; }
.review-verified::before { content: '●'; font-size: 6px; }
.review-platform { font-size: var(--fs-footnote); color: var(--color-text-muted); margin-top: 12pt; text-align: center; font-style: italic; text-indent: 0 !important; }
.review-platform a { color: var(--color-text-muted); text-decoration: underline; }
.review-stars { color: var(--color-accent); font-style: normal; letter-spacing: 1px; }

/* === CTA === */
.cta-button { display: inline-block; margin-top: 10pt; padding: 10pt 28pt; font-family: var(--font-serif); font-size: var(--fs-body); font-variant: small-caps; letter-spacing: 0.06em; color: #fff !important; background: var(--color-text); border: none; cursor: pointer; text-decoration: none !important; transition: background 0.2s, transform 0.1s; }
.cta-button:hover { background: var(--color-accent); color: #fff !important; text-decoration: none !important; transform: translateY(-1px); }
.cta-button-wa { display: inline-block; margin-top: 8pt; margin-left: 10pt; padding: 10pt 24pt; font-family: var(--font-mono); font-size: var(--fs-small); color: var(--color-text); background: transparent; border: 1pt solid var(--color-text); cursor: pointer; text-decoration: none; transition: all 0.2s; }
.cta-button-wa:hover { border-color: var(--color-accent); color: var(--color-accent); text-decoration: none; }
.inline-cta { margin: 20pt 0; padding: 14pt 20pt; border-top: 0.5pt solid var(--color-rule-light); border-bottom: 0.5pt solid var(--color-rule-light); display: flex; align-items: center; justify-content: space-between; gap: 16pt; }
.inline-cta-text { font-size: var(--fs-small); color: var(--color-text-secondary); font-style: italic; flex: 1; text-align: left !important; text-indent: 0 !important; }
.inline-cta-button { display: inline-block; padding: 7pt 18pt; font-family: var(--font-serif); font-size: var(--fs-small); font-variant: small-caps; letter-spacing: 0.04em; color: #fff !important; background: var(--color-text); text-decoration: none !important; white-space: nowrap; transition: background 0.2s; flex-shrink: 0; }
.inline-cta-button:hover { background: var(--color-accent); color: #fff !important; text-decoration: none !important; }
.inline-cta-wa { display: inline-block; padding: 7pt 16pt; font-family: var(--font-mono); font-size: var(--fs-footnote); color: var(--color-text-secondary); border: 0.5pt solid var(--color-rule-light); text-decoration: none; white-space: nowrap; transition: all 0.2s; flex-shrink: 0; margin-left: 8pt; }
.inline-cta-wa:hover { border-color: var(--color-accent); color: var(--color-accent); text-decoration: none; }

/* === CONTACT FORM === */
.inquiry-env { margin: 24pt 0; padding: 24pt; border: 1pt solid var(--color-rule); background: #fcfcfc; }
.inquiry-env .env-label { font-weight: 700; font-variant: small-caps; letter-spacing: 0.03em; margin-bottom: 4pt; display: block; font-size: var(--fs-subsection); text-align: center; }
.inquiry-env .env-sublabel { font-size: var(--fs-small); font-style: italic; color: var(--color-text-secondary); margin-bottom: 16pt; text-align: center; display: block; }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14pt; margin-bottom: 14pt; }
.form-field { display: flex; flex-direction: column; }
.form-field.full-width { grid-column: 1 / -1; }
.form-field label { font-size: var(--fs-footnote); font-variant: small-caps; letter-spacing: 0.03em; color: var(--color-text-secondary); margin-bottom: 4pt; }
.form-field input, .form-field select, .form-field textarea { font-family: var(--font-serif); font-size: var(--fs-small); padding: 8pt 10pt; border: 0.5pt solid var(--color-rule-light); background: var(--color-paper); color: var(--color-text); }
.form-field textarea { min-height: 80px; resize: vertical; }
.form-field input:focus, .form-field select:focus, .form-field textarea:focus { outline: none; border-color: var(--color-accent); }
.form-actions { text-align: center; margin-top: 6pt; }
.form-or { display: block; margin-top: 12pt; font-size: var(--fs-small); color: var(--color-text-muted); text-align: center; }
.form-wa-alt { text-align: center; margin-top: 8pt; }
.form-privacy { font-size: var(--fs-footnote); color: var(--color-text-muted); text-align: center; margin-top: 12pt; }

/* === FAQ === */
.faq-item { margin-bottom: 14pt; }
.faq-question { font-weight: 700; font-style: italic; cursor: pointer; display: flex; align-items: baseline; gap: 8px; user-select: none; }
.faq-question::before { content: '▸'; font-style: normal; transition: transform 0.2s; display: inline-block; font-size: 0.8em; }
.faq-item.open .faq-question::before { transform: rotate(90deg); }
.faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.35s ease, padding 0.35s ease; padding-left: 18px; }
.faq-item.open .faq-answer { max-height: 500px; padding-top: 6pt; }

/* === LISTS === */
.paper ul, .paper ol { margin: 8pt 0 8pt 24pt; }
.paper li { margin-bottom: 4pt; text-align: justify; }
.paper ul li::marker { content: '–  '; color: var(--color-text-muted); }

/* === FOOTNOTES / BIB === */
.footnote-ref { font-size: 0.75em; vertical-align: super; line-height: 0; color: var(--color-accent); text-decoration: none; }
.footnotes-section { margin-top: 36pt; padding-top: 12pt; border-top: 0.5pt solid var(--color-rule-light); font-size: var(--fs-footnote); color: var(--color-text-secondary); }
.footnotes-section ol { margin-left: 16pt; }
.bibliography { margin-top: 28pt; }
.bib-entry { margin-bottom: 6pt; padding-left: 2em; text-indent: -2em; font-size: var(--fs-small); }
.bib-key { font-weight: 700; }

/* === FOOTER === */
.paper-footer { margin-top: 48pt; padding-top: 12pt; border-top: 0.5pt solid var(--color-rule-light); font-size: var(--fs-footnote); color: var(--color-text-muted); display: flex; justify-content: space-between; align-items: flex-end; }
.paper-footer a { color: var(--color-text-muted); }
.page-number { font-style: italic; }

/* === RATGEBER INDEX === */
.ratgeber-item { margin-bottom: 16pt; padding-bottom: 12pt; border-bottom: 0.5pt solid var(--color-rule-light); }
.ratgeber-item a { color: var(--color-text); }
.ratgeber-item a:hover { color: var(--color-accent); }

/* === WA FLOATING === */
.wa-float { display: none; position: fixed; bottom: 28px; right: 28px; z-index: 98; }
.wa-float a { display: flex; align-items: center; gap: 8px; padding: 10px 18px; background: var(--color-text); color: #fff !important; font-family: var(--font-mono); font-size: var(--fs-small); text-decoration: none !important; transition: background 0.2s; box-shadow: 0 2px 12px rgba(0,0,0,0.15); }
.wa-float a:hover { background: var(--color-accent); }

/* === STICKY MOBILE CTA === */
.sticky-cta { display: none; position: fixed; bottom: 0; left: 0; right: 0; z-index: 99; background: var(--color-paper); border-top: 1pt solid var(--color-rule-light); padding: 8px 16px; box-shadow: 0 -2px 12px rgba(0,0,0,0.08); transform: translateY(100%); transition: transform 0.35s; }
.sticky-cta.visible { transform: translateY(0); }
.sticky-cta-inner { display: flex; gap: 8px; }
.sticky-cta-main { flex: 1; display: block; padding: 10pt 0; font-family: var(--font-serif); font-size: var(--fs-small); font-variant: small-caps; letter-spacing: 0.05em; color: #fff !important; background: var(--color-text); text-decoration: none !important; text-align: center; transition: background 0.2s; }
.sticky-cta-main:hover { background: var(--color-accent); }
.sticky-cta-wa { display: flex; align-items: center; justify-content: center; padding: 10pt 14pt; font-family: var(--font-mono); font-size: var(--fs-small); color: var(--color-text); border: 1pt solid var(--color-text); text-decoration: none; transition: all 0.2s; white-space: nowrap; }
.sticky-cta-wa:hover { border-color: var(--color-accent); color: var(--color-accent); }

/* === ANIMATIONS === */
@keyframes fadeInUp { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }
.animate-in { opacity: 0; animation: fadeInUp 0.5s ease forwards; }
.delay-1 { animation-delay: 0.1s; } .delay-2 { animation-delay: 0.2s; } .delay-3 { animation-delay: 0.3s; }

/* === RESPONSIVE === */
@media (min-width: 920px) { .wa-float { display: block; } }

@media (max-width: 919px) {
    .paper { padding: 20px 24px; padding-top: 70px; }
    .nav-inner { padding: 10px 24px; }
    .title-block { padding-top: 20px; }
    .paper-title { font-size: 20pt; }
    .abstract-block { margin: 0 0 18pt; }
    .keywords-block { margin: 10pt 0 0; }
    .proposition-list, .lemma-grid { grid-template-columns: 1fr; }
    .calc-grid { grid-template-columns: 1fr; }
    .process-flow { flex-direction: column; }
    .process-arrow { transform: rotate(90deg); margin: -8px 0; }
    .author-bio { flex-direction: column; align-items: center; text-align: center; }
    .author-bio-text p { text-align: center; }
    .author-bio-facts { justify-content: center; }
    .nav-links { display: none; flex-direction: column; position: absolute; top: 100%; left: 0; right: 0; background: rgba(254,254,254,0.97); backdrop-filter: blur(10px); padding: 16px 24px; border-bottom: 0.5pt solid var(--color-rule-light); gap: 16px; }
    .nav-links.active { display: flex; }
    .nav-hamburger { display: block; }
    .inline-cta { flex-direction: column; text-align: center; }
    .inline-cta-text { text-align: center !important; }
    .inline-cta-wa { margin-left: 0; margin-top: 6pt; }
    .cta-button, .cta-button-wa { display: block; margin-left: 0; text-align: center; }
    .form-grid { grid-template-columns: 1fr; }
    .sticky-cta { display: block; }
    .paper-footer { flex-direction: column; gap: 8pt; text-align: center; padding-bottom: 80px; }
}

@media (max-width: 480px) {
    .paper { padding: 16px 18px; padding-top: 66px; }
    .paper-title { font-size: 17pt; }
    .section-title { font-size: 14.4pt; }
    .subsection-title { font-size: 12pt; }
    .hero-stat-number { font-size: 22pt; }
    .hero-stats { gap: 16px; }
    .hero-stat-divider { display: none; }
    .latex-table { font-size: var(--fs-small); }
    .latex-table thead th, .latex-table tbody td { padding: 5pt 5pt; }
}

@media print {
    body { background: white; padding: 0; }
    .paper { box-shadow: none; max-width: 100%; padding: 0; }
    .paper-nav, .sticky-cta, .inline-cta, .hero-cta, .wa-float, .calculator-env { display: none !important; }
    .faq-answer { max-height: none !important; padding-top: 6pt !important; }
}