/* ============================================================
   Hanyu Peixun — main.css
   Typeface: Instrument Serif (display) + Hanken Grotesk (body)
   Rationale: Serif warmth for a language-learning brand rooted
   in culture; Hanken's clean grotesque keeps content readable.
   Prefix: rrdur-
   ============================================================ */

/* ---- reset ---- */
*,
*::before,
*::after { box-sizing: border-box; margin: 0; padding: 0; }
img, video { max-width: 100%; display: block; }
ul, ol { list-style: none; }
a { text-decoration: none; color: inherit; }
button { cursor: pointer; border: none; background: none; font: inherit; }
input, textarea, select { font: inherit; }

/* ---- tokens ---- */
:root {
  /* colours */
  --clr-bg:          #FAFAF7;
  --clr-surface:     #FFFFFF;
  --clr-border:      #E4E2DC;
  --clr-text:        #1A1A18;
  --clr-muted:       #6B6B65;
  --clr-accent:      #E8552E;
  --clr-accent-dark: #C03D1A;
  --clr-ink:         #1E2A3A;
  --clr-ink-light:   #2F3F54;
  --clr-tag-bg:      #FFF0EC;
  --clr-tag-text:    #C03D1A;

  /* spacing */
  --sp-2:  0.125rem;
  --sp-4:  0.25rem;
  --sp-8:  0.5rem;
  --sp-12: 0.75rem;
  --sp-16: 1rem;
  --sp-20: 1.25rem;
  --sp-24: 1.5rem;
  --sp-32: 2rem;
  --sp-40: 2.5rem;
  --sp-48: 3rem;
  --sp-56: 3.5rem;
  --sp-64: 4rem;
  --sp-80: 5rem;
  --sp-96: 6rem;

  /* radius */
  --radius-sm:  4px;
  --radius-md:  8px;
  --radius-lg:  16px;
  --radius-pill: 999px;

  /* shadow */
  --shadow-sm: 0 1px 3px rgba(0,0,0,.06), 0 1px 2px rgba(0,0,0,.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,.08), 0 2px 4px rgba(0,0,0,.04);
  --shadow-lg: 0 12px 32px rgba(0,0,0,.10);

  /* transitions */
  --ease:        cubic-bezier(.25,.46,.45,.94);
  --tr-fast:     0.15s var(--ease);
  --tr-base:     0.25s var(--ease);
  --tr-slow:     0.4s  var(--ease);

  /* z-index */
  --z-base:       1;
  --z-header:    50;
  --z-mobile:    60;
  --z-cookie:    80;
  --z-back-to-top: 70;

  /* layout */
  --header-h:    64px;
  --max-w:       1200px;
  --content-w:   760px;

  /* logo */
  --logo-w: 160px;
  --logo-h: 40px;
}

/* ---- base ---- */
html { scroll-behavior: smooth; }

body {
  font-family: 'Hanken Grotesk', system-ui, sans-serif;
  font-size: 1rem;
  line-height: 1.65;
  color: var(--clr-text);
  background: var(--clr-bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Instrument Serif', Georgia, serif;
  line-height: 1.2;
  color: var(--clr-ink);
}

p { max-width: 70ch; }

main { padding-top: var(--header-h); }

/* ---- layout ---- */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: var(--sp-20);
}

.section {
  padding-block: var(--sp-80);
}

.section--tight {
  padding-block: var(--sp-48);
}

/* ---- header ---- */
#site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-h);
  background: rgba(250, 250, 247, 0.95);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--clr-border);
  z-index: var(--z-header);
  overflow: hidden;
}

.nav-inner {
  display: flex;
  align-items: center;
  height: var(--header-h);
  gap: var(--sp-32);
  overflow: hidden;
}

.rrdur-logo {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.rrdur-logo img {
  max-width: var(--logo-w);
  max-height: var(--logo-h);
  width: auto;
  height: auto;
  display: block;
}

.nav-links {
  display: none;
  align-items: center;
  gap: var(--sp-4);
  margin-left: auto;
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--clr-muted);
  padding: var(--sp-8) var(--sp-12);
  border-radius: var(--radius-sm);
  transition: color var(--tr-fast), background var(--tr-fast);
  white-space: nowrap;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--clr-accent);
  background: var(--clr-tag-bg);
}

.hamburger {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  padding: var(--sp-8);
  margin-left: auto;
  border-radius: var(--radius-sm);
  transition: background var(--tr-fast);
}

.hamburger:hover { background: var(--clr-border); }

.hamburger span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--clr-ink);
  border-radius: 2px;
  transition: transform var(--tr-base), opacity var(--tr-base);
}

.hamburger.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.is-open span:nth-child(2) { opacity: 0; }
.hamburger.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---- mobile menu ---- */
.mobile-menu {
  display: flex;
  flex-direction: column;
  position: fixed;
  top: var(--header-h);
  left: 0; right: 0; bottom: 0;
  background: var(--clr-surface);
  border-top: 1px solid var(--clr-border);
  z-index: var(--z-mobile);
  padding: var(--sp-24) var(--sp-20);
  gap: var(--sp-4);
  overflow-y: auto;
  visibility: hidden;
  opacity: 0;
  pointer-events: none;
  transform: translateY(-8px);
  transition: opacity 0.2s ease, transform 0.2s ease, visibility 0s linear 0.2s;
}

.mobile-menu.open {
  visibility: visible;
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
  transition: opacity 0.2s ease, transform 0.2s ease, visibility 0s linear 0s;
}

.mobile-menu a {
  font-size: 1.05rem;
  font-weight: 500;
  color: var(--clr-ink);
  padding: var(--sp-12) var(--sp-16);
  border-radius: var(--radius-md);
  transition: background var(--tr-fast), color var(--tr-fast);
}

.mobile-menu a:hover,
.mobile-menu a.active {
  background: var(--clr-tag-bg);
  color: var(--clr-accent);
}

/* ---- breadcrumb ---- */
.rrdur-breadcrumb {
  padding-block: var(--sp-16);
  border-bottom: 1px solid var(--clr-border);
  margin-bottom: var(--sp-40);
}

.rrdur-breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-8);
  align-items: center;
  font-size: 0.85rem;
  color: var(--clr-muted);
}

.rrdur-breadcrumb li + li::before {
  content: "›";
  margin-right: var(--sp-8);
  color: var(--clr-border);
}

.rrdur-breadcrumb a {
  color: var(--clr-muted);
  transition: color var(--tr-fast);
}

.rrdur-breadcrumb a:hover { color: var(--clr-accent); }
.rrdur-breadcrumb [aria-current] { color: var(--clr-text); font-weight: 500; }

/* ---- hero typography (homepage) ---- */
.rrdur-hero {
  background: var(--clr-ink);
  color: #fff;
  padding-block: var(--sp-80) var(--sp-96);
  position: relative;
  overflow: hidden;
}

.rrdur-hero::after {
  content: "汉语";
  position: absolute;
  right: -0.05em;
  top: 50%;
  transform: translateY(-50%);
  font-family: 'Instrument Serif', serif;
  font-size: clamp(8rem, 20vw, 18rem);
  line-height: 1;
  color: rgba(232,85,46,.12);
  pointer-events: none;
  user-select: none;
}

.rrdur-hero__label {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--clr-accent);
  margin-bottom: var(--sp-24);
}

.rrdur-hero__title {
  font-family: 'Instrument Serif', serif;
  font-size: clamp(2.4rem, 6vw, 4.2rem);
  color: #fff;
  max-width: 15ch;
  margin-bottom: var(--sp-24);
}

.rrdur-hero__subtitle {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: rgba(255,255,255,.72);
  max-width: 50ch;
  margin-bottom: var(--sp-40);
}

.rrdur-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-16);
  align-items: center;
}

/* ---- buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-8);
  padding: var(--sp-12) var(--sp-24);
  border-radius: var(--radius-pill);
  font-size: 0.95rem;
  font-weight: 600;
  transition: background var(--tr-fast), color var(--tr-fast), box-shadow var(--tr-fast), transform var(--tr-fast);
}

.btn:hover { transform: translateY(-1px); }

.btn--primary {
  background: var(--clr-accent);
  color: #fff;
  box-shadow: var(--shadow-sm);
}

.btn--primary:hover {
  background: var(--clr-accent-dark);
  box-shadow: var(--shadow-md);
}

.btn--ghost {
  background: transparent;
  color: rgba(255,255,255,.85);
  border: 1.5px solid rgba(255,255,255,.3);
}

.btn--ghost:hover {
  background: rgba(255,255,255,.08);
  border-color: rgba(255,255,255,.5);
}

.btn--outline {
  background: transparent;
  color: var(--clr-accent);
  border: 1.5px solid var(--clr-accent);
}

.btn--outline:hover {
  background: var(--clr-tag-bg);
}

/* ---- what-to-learn selector (homepage unique component) ---- */
.rrdur-selector {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.rrdur-selector__tabs {
  display: flex;
  border-bottom: 1px solid var(--clr-border);
  overflow-x: auto;
}

.rrdur-selector__tab {
  flex: 1;
  min-width: 120px;
  padding: var(--sp-16) var(--sp-20);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--clr-muted);
  background: none;
  border-bottom: 2px solid transparent;
  transition: color var(--tr-fast), border-color var(--tr-fast), background var(--tr-fast);
  white-space: nowrap;
  text-align: center;
  cursor: pointer;
}

.rrdur-selector__tab:hover { color: var(--clr-text); background: var(--clr-bg); }

.rrdur-selector__tab.active {
  color: var(--clr-accent);
  border-bottom-color: var(--clr-accent);
  background: var(--clr-tag-bg);
}

.rrdur-selector__panels { padding: var(--sp-32); }

.rrdur-selector__panel { display: none; }
.rrdur-selector__panel.active { display: block; }

.rrdur-selector__panel h3 {
  font-size: 1.4rem;
  margin-bottom: var(--sp-12);
}

.rrdur-selector__panel p {
  color: var(--clr-muted);
  margin-bottom: var(--sp-20);
}

.rrdur-selector__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-8);
}

.rrdur-tag {
  display: inline-flex;
  align-items: center;
  padding: var(--sp-4) var(--sp-12);
  border-radius: var(--radius-pill);
  font-size: 0.8rem;
  font-weight: 600;
  background: var(--clr-tag-bg);
  color: var(--clr-tag-text);
}

/* ---- stats strip ---- */
.rrdur-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1px;
  background: var(--clr-border);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.rrdur-stat {
  background: var(--clr-surface);
  padding: var(--sp-32) var(--sp-24);
  text-align: center;
}

.rrdur-stat__number {
  font-family: 'Instrument Serif', serif;
  font-size: 2.4rem;
  color: var(--clr-accent);
  line-height: 1;
  display: block;
  margin-bottom: var(--sp-8);
}

.rrdur-stat__label {
  font-size: 0.85rem;
  color: var(--clr-muted);
  font-weight: 500;
}

/* ---- section heading ---- */
.rrdur-section-label {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--clr-accent);
  display: block;
  margin-bottom: var(--sp-12);
}

.rrdur-section-title {
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  margin-bottom: var(--sp-16);
}

.rrdur-section-sub {
  font-size: 1.05rem;
  color: var(--clr-muted);
  max-width: 55ch;
}

/* ---- card grid ---- */
.rrdur-grid {
  display: grid;
  gap: var(--sp-24);
}

.rrdur-grid--2 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.rrdur-grid--3 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }

/* ---- insights card ---- */
.rrdur-card {
  display: block;
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: box-shadow var(--tr-base), transform var(--tr-base);
}

.rrdur-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.rrdur-card__img {
  width: 100%;
  aspect-ratio: 16/9;
  object-fit: cover;
}

.rrdur-card__body { padding: var(--sp-24); }

.rrdur-card__tag {
  display: inline-block;
  margin-bottom: var(--sp-12);
}

.rrdur-card__title {
  font-size: 1.15rem;
  margin-bottom: var(--sp-12);
  line-height: 1.3;
}

.rrdur-card__excerpt {
  font-size: 0.9rem;
  color: var(--clr-muted);
  margin-bottom: var(--sp-20);
  max-width: none;
}

.rrdur-card__meta {
  display: flex;
  align-items: center;
  gap: var(--sp-12);
  font-size: 0.82rem;
  color: var(--clr-muted);
}

/* ---- services list ---- */
.rrdur-service {
  padding: var(--sp-40);
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  transition: box-shadow var(--tr-base);
}

.rrdur-service:hover { box-shadow: var(--shadow-md); }

.rrdur-service__badge {
  display: inline-block;
  width: 40px; height: 40px;
  background: var(--clr-tag-bg);
  border-radius: var(--radius-md);
  margin-bottom: var(--sp-20);
  display: flex;
  align-items: center;
  justify-content: center;
}

.rrdur-service__badge svg {
  width: 22px; height: 22px;
  color: var(--clr-accent);
}

.rrdur-service__label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--clr-accent);
  display: block;
  margin-bottom: var(--sp-8);
}

.rrdur-service h3 {
  font-size: 1.4rem;
  margin-bottom: var(--sp-12);
}

.rrdur-service p {
  color: var(--clr-muted);
  margin-bottom: var(--sp-20);
  font-size: 0.95rem;
}

.rrdur-service__includes {
  margin-top: var(--sp-16);
  display: flex;
  flex-direction: column;
  gap: var(--sp-8);
}

.rrdur-service__includes li {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-10);
  font-size: 0.88rem;
  color: var(--clr-text);
}

.rrdur-service__includes li::before {
  content: "";
  display: block;
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--clr-accent);
  margin-top: 0.5em;
  flex-shrink: 0;
}

.rrdur-service__note {
  margin-top: var(--sp-20);
  padding: var(--sp-12) var(--sp-16);
  background: var(--clr-bg);
  border-left: 3px solid var(--clr-accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.85rem;
  color: var(--clr-muted);
}

/* ---- article body ---- */
.rrdur-article {
  max-width: var(--content-w);
  margin-inline: auto;
}

.rrdur-article h2 {
  font-size: 1.6rem;
  margin-top: var(--sp-48);
  margin-bottom: var(--sp-16);
}

.rrdur-article h3 {
  font-size: 1.25rem;
  margin-top: var(--sp-32);
  margin-bottom: var(--sp-12);
}

.rrdur-article p {
  color: var(--clr-text);
  margin-bottom: var(--sp-20);
  font-size: 1.02rem;
  line-height: 1.75;
  max-width: none;
}

.rrdur-article ul, .rrdur-article ol {
  margin-bottom: var(--sp-20);
  padding-left: var(--sp-24);
}

.rrdur-article ul { list-style: disc; }
.rrdur-article ol { list-style: decimal; }

.rrdur-article li { margin-bottom: var(--sp-8); font-size: 1.02rem; }

.rrdur-article blockquote {
  border-left: 3px solid var(--clr-accent);
  padding-left: var(--sp-20);
  margin-block: var(--sp-32);
  font-style: italic;
  color: var(--clr-muted);
}

/* ---- post hero ---- */
.rrdur-post-hero {
  margin-bottom: var(--sp-48);
}

.rrdur-post-hero__img {
  width: 100%;
  max-height: 480px;
  object-fit: cover;
  border-radius: var(--radius-lg);
  margin-bottom: var(--sp-32);
}

.rrdur-post-hero__label { margin-bottom: var(--sp-12); }

.rrdur-post-hero__title {
  font-size: clamp(1.8rem, 4vw, 3rem);
  margin-bottom: var(--sp-16);
}

.rrdur-post-hero__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--sp-16);
  font-size: 0.88rem;
  color: var(--clr-muted);
}

/* ---- newsletter CTA (first post only) ---- */
.rrdur-newsletter {
  margin-block: var(--sp-48);
  padding: var(--sp-32);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  background: var(--clr-surface);
}

.rrdur-newsletter h3 {
  font-size: 1.2rem;
  margin-bottom: var(--sp-8);
}

.rrdur-newsletter p {
  font-size: 0.9rem;
  color: var(--clr-muted);
  margin-bottom: var(--sp-20);
}

.rrdur-newsletter__form {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-12);
}

.rrdur-newsletter input[type="email"] {
  flex: 1;
  min-width: 200px;
  padding: var(--sp-12) var(--sp-16);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-pill);
  font-size: 0.9rem;
  background: var(--clr-bg);
  transition: border-color var(--tr-fast);
}

.rrdur-newsletter input[type="email"]:focus {
  outline: none;
  border-color: var(--clr-accent);
}

.rrdur-newsletter__confirm {
  display: none;
  font-size: 0.9rem;
  color: var(--clr-muted);
  padding: var(--sp-12) 0;
}

/* ---- contact form ---- */
.rrdur-form {
  display: flex;
  flex-direction: column;
  gap: var(--sp-20);
}

.rrdur-form__group {
  display: flex;
  flex-direction: column;
  gap: var(--sp-8);
}

.rrdur-form label {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--clr-ink);
}

.rrdur-form input,
.rrdur-form textarea,
.rrdur-form select {
  padding: var(--sp-12) var(--sp-16);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  background: var(--clr-bg);
  color: var(--clr-text);
  transition: border-color var(--tr-fast), box-shadow var(--tr-fast);
}

.rrdur-form input:focus,
.rrdur-form textarea:focus,
.rrdur-form select:focus {
  outline: none;
  border-color: var(--clr-accent);
  box-shadow: 0 0 0 3px rgba(232,85,46,.12);
}

.rrdur-form textarea { resize: vertical; min-height: 120px; }

.rrdur-form__captcha {
  display: flex;
  align-items: center;
  gap: var(--sp-12);
  flex-wrap: wrap;
}

.rrdur-form__captcha label {
  font-weight: 400;
  color: var(--clr-muted);
}

.rrdur-form__captcha input {
  width: 80px;
}

.rrdur-form__error {
  font-size: 0.82rem;
  color: #C0392B;
  display: none;
}

.rrdur-form__success {
  display: none;
  padding: var(--sp-24);
  background: #F0FFF4;
  border: 1px solid #68D391;
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  color: #276749;
}

/* ---- about team ---- */
.rrdur-team {
  display: grid;
  gap: var(--sp-32);
}

.rrdur-team-member {
  display: flex;
  flex-direction: column;
  gap: var(--sp-16);
  padding: var(--sp-32);
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
}

.rrdur-team-member h3 {
  font-size: 1.2rem;
  margin-bottom: var(--sp-4);
}

.rrdur-team-member__role {
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--clr-accent);
  display: block;
  margin-bottom: var(--sp-12);
}

.rrdur-team-member p {
  font-size: 0.92rem;
  color: var(--clr-muted);
  max-width: none;
}

.rrdur-team-member a {
  font-size: 0.85rem;
  color: var(--clr-accent);
  font-weight: 500;
}

.rrdur-team-member a:hover { text-decoration: underline; }

/* ---- legal pages ---- */
.rrdur-legal h2 {
  font-size: 1.4rem;
  margin-top: var(--sp-40);
  margin-bottom: var(--sp-12);
}

.rrdur-legal h3 {
  font-size: 1.1rem;
  margin-top: var(--sp-24);
  margin-bottom: var(--sp-8);
}

.rrdur-legal p {
  font-size: 0.95rem;
  color: var(--clr-muted);
  margin-bottom: var(--sp-16);
  max-width: none;
}

.rrdur-legal ul {
  list-style: disc;
  padding-left: var(--sp-24);
  margin-bottom: var(--sp-16);
}

.rrdur-legal li {
  font-size: 0.95rem;
  color: var(--clr-muted);
  margin-bottom: var(--sp-8);
}

/* ---- page hero (inner pages) ---- */
.rrdur-page-hero {
  background: var(--clr-ink);
  color: #fff;
  padding-block: var(--sp-64);
}

.rrdur-page-hero h1 {
  font-size: clamp(1.8rem, 4vw, 3rem);
  color: #fff;
  margin-bottom: var(--sp-16);
}

.rrdur-page-hero p {
  font-size: 1.05rem;
  color: rgba(255,255,255,.7);
  max-width: 55ch;
}

/* ---- accordion FAQ ---- */
.rrdur-accordion { display: flex; flex-direction: column; gap: var(--sp-2); }

.rrdur-accordion__item {
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--clr-surface);
}

.rrdur-accordion__trigger {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  padding: var(--sp-20) var(--sp-24);
  font-size: 1rem;
  font-weight: 600;
  text-align: left;
  color: var(--clr-ink);
  transition: background var(--tr-fast);
}

.rrdur-accordion__trigger:hover { background: var(--clr-bg); }

.rrdur-accordion__trigger svg {
  width: 18px; height: 18px;
  flex-shrink: 0;
  transition: transform var(--tr-base);
  color: var(--clr-muted);
}

.rrdur-accordion__item.open .rrdur-accordion__trigger svg { transform: rotate(180deg); }

.rrdur-accordion__body {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--tr-slow);
}

.rrdur-accordion__item.open .rrdur-accordion__body { max-height: 400px; }

.rrdur-accordion__content {
  padding: 0 var(--sp-24) var(--sp-20);
  font-size: 0.95rem;
  color: var(--clr-muted);
}

/* ---- progress bar ---- */
#reading-progress {
  position: fixed;
  top: var(--header-h);
  left: 0;
  width: 0%;
  height: 3px;
  background: var(--clr-accent);
  z-index: var(--z-header);
  transition: width 0.1s linear;
}

/* ---- footer ---- */
footer {
  background: var(--clr-ink);
  color: rgba(255,255,255,.72);
  padding-block: var(--sp-64) var(--sp-40);
}

.footer-grid {
  display: grid;
  gap: var(--sp-40);
  margin-bottom: var(--sp-56);
}

.footer-brand .rrdur-logo img { filter: brightness(0) invert(1); }

.footer-brand__desc {
  font-size: 0.9rem;
  color: rgba(255,255,255,.5);
  margin-top: var(--sp-16);
  max-width: 28ch;
}

.footer-col h4 {
  font-family: 'Hanken Grotesk', sans-serif;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: rgba(255,255,255,.4);
  margin-bottom: var(--sp-16);
}

.footer-col a {
  display: block;
  font-size: 0.9rem;
  color: rgba(255,255,255,.65);
  margin-bottom: var(--sp-10);
  transition: color var(--tr-fast);
}

.footer-col a:hover { color: var(--clr-accent); }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.1);
  padding-top: var(--sp-32);
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-16);
  justify-content: space-between;
  align-items: center;
}

.footer-bottom p {
  font-size: 0.82rem;
  color: rgba(255,255,255,.35);
  max-width: none;
}

.footer-legal {
  display: flex;
  gap: var(--sp-20);
  flex-wrap: wrap;
}

.footer-legal a {
  font-size: 0.82rem;
  color: rgba(255,255,255,.4);
  transition: color var(--tr-fast);
}

.footer-legal a:hover { color: var(--clr-accent); }

/* ---- cookie banner ---- */
#cookie-banner {
  position: fixed;
  bottom: 0; left: 0; right: 0;
  background: var(--clr-ink);
  color: rgba(255,255,255,.85);
  padding: var(--sp-20) var(--sp-24);
  z-index: var(--z-cookie);
  border-top: 3px solid var(--clr-accent);
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-16);
  align-items: center;
  justify-content: space-between;
  transform: translateY(100%);
  transition: transform 0.35s var(--ease);
}

#cookie-banner.visible { transform: translateY(0); }

#cookie-banner p {
  font-size: 0.88rem;
  flex: 1;
  min-width: 240px;
  max-width: none;
}

#cookie-banner a { color: var(--clr-accent); }
#cookie-banner a:hover { text-decoration: underline; }

.cookie-actions { display: flex; gap: var(--sp-10); }

#cookie-accept {
  padding: var(--sp-8) var(--sp-20);
  background: var(--clr-accent);
  color: #fff;
  border-radius: var(--radius-pill);
  font-size: 0.85rem;
  font-weight: 600;
  transition: background var(--tr-fast);
}

#cookie-accept:hover { background: var(--clr-accent-dark); }

#cookie-decline {
  padding: var(--sp-8) var(--sp-16);
  color: rgba(255,255,255,.55);
  border: 1px solid rgba(255,255,255,.2);
  border-radius: var(--radius-pill);
  font-size: 0.85rem;
  transition: color var(--tr-fast), border-color var(--tr-fast);
}

#cookie-decline:hover { color: #fff; border-color: rgba(255,255,255,.4); }

/* ---- back to top ---- */
#back-to-top {
  position: fixed;
  bottom: var(--sp-32);
  right: var(--sp-24);
  width: 44px; height: 44px;
  background: var(--clr-accent);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-back-to-top);
  box-shadow: var(--shadow-md);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--tr-base), transform var(--tr-base);
}

#back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
}

#back-to-top:hover { transform: translateY(-3px); }

#back-to-top svg { width: 20px; height: 20px; }

/* ---- animations ---- */
.rrdur-reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.55s var(--ease), transform 0.55s var(--ease);
}

.rrdur-reveal.in-view {
  opacity: 1;
  transform: translateY(0);
}

@keyframes rrdur-fade-in {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ---- responsive ---- */
@media (min-width: 1025px) {
  .nav-links { display: flex; }
  .hamburger  { display: none; }
}

@media (max-width: 1024px) {
  .nav-links { display: none; }
  .hamburger  { display: flex; }
}

@media (min-width: 768px) {
  .footer-grid {
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
  }
  .rrdur-team {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 767px) {
  .rrdur-hero { padding-block: var(--sp-64) var(--sp-80); }
  .rrdur-hero::after { display: none; }
  .section { padding-block: var(--sp-56); }
  .rrdur-page-hero { padding-block: var(--sp-48); }
  .rrdur-service { padding: var(--sp-24); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .rrdur-reveal {
    opacity: 1;
    transform: none;
  }
}