/* =========================================================
   Research case study — Eco-Feedback
   ========================================================= */

.rcs-back {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--muted);
  padding: 28px 0 0;
}
.rcs-back:hover { color: var(--ink); }

/* ---------- Hero ---------- */
.rcs-hero {
  padding: clamp(28px, 4vw, 56px) 0 clamp(56px, 7vw, 96px);
  background: #FBFAF7;
  border-bottom: 1px solid var(--line);
  position: relative;
  overflow: hidden;
}
.rcs-hero__grid {
  display: grid;
  grid-template-columns: 1fr 1.05fr;
  gap: clamp(40px, 6vw, 96px);
  align-items: center;
}
.rcs-hero__eyebrow {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--muted);
  margin-bottom: 24px;
}
.rcs-hero__title {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(44px, 6vw, 82px);
  line-height: 0.98;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin-bottom: 24px;
}
.rcs-hero__sub {
  font-size: clamp(16px, 1.3vw, 19px);
  line-height: 1.5;
  color: var(--ink-soft);
  max-width: 56ch;
  margin-bottom: 36px;
}
.rcs-meta {
  display: grid;
  grid-template-columns: repeat(3, auto);
  gap: clamp(20px, 3vw, 48px);
  margin-bottom: 36px;
}
.rcs-meta__item { display: flex; gap: 12px; align-items: flex-start; }
.rcs-meta__icon {
  width: 36px; height: 36px; border: 1px solid var(--line);
  border-radius: 6px; display: inline-flex; align-items: center; justify-content: center;
  color: var(--ink); flex-shrink: 0;
}
.rcs-meta__icon svg { width: 16px; height: 16px; }
.rcs-meta__label { font-size: 13.5px; color: var(--ink); line-height: 1.2; }
.rcs-meta__value {
  font-size: 11.5px; color: var(--muted); margin-top: 2px;
  font-family: var(--mono); letter-spacing: 0.1em; text-transform: uppercase;
}
.rcs-hero__ctas { display: flex; gap: 16px; flex-wrap: wrap; align-items: center; }
.rcs-hero__download {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 14.5px; color: var(--ink);
}
.rcs-hero__download:hover { color: var(--accent-ink); }
.rcs-hero__visual {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--bg);
  position: relative;
}
.rcs-hero__visual--ph { aspect-ratio: 16 / 11; }
.rcs-hero__visual img { width: 100%; height: auto; display: block; }
@media (max-width: 880px) {
  .rcs-hero__grid { grid-template-columns: 1fr; }
}

/* ---------- Section labels ---------- */
.rcs-section {
  padding: clamp(56px, 7vw, 96px) 0;
  border-bottom: 1px solid var(--line);
}
.rcs-section--bg { background: #FBFAF7; }
.rcs-label {
  display: flex; align-items: center; gap: 14px;
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--ink);
  margin-bottom: clamp(28px, 4vw, 48px);
}
.rcs-label__num { color: var(--muted); }
.rcs-label__rule { flex: 1; height: 1px; background: var(--line); }

/* ---------- 01 Problem ---------- */
.rcs-problem {
  display: grid; grid-template-columns: 64px 1fr;
  gap: 24px; max-width: 720px;
}
.rcs-problem__icon {
  width: 48px; height: 48px; border-radius: 50%;
  background: var(--bg-alt);
  display: inline-flex; align-items: center; justify-content: center;
  font-family: var(--serif); font-size: 22px; color: var(--ink);
}
.rcs-problem__text {
  font-size: clamp(15px, 1.1vw, 17px);
  line-height: 1.6; color: var(--ink-soft);
}

/* ---------- 02 Insights ---------- */
.rcs-insights {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: clamp(20px, 2.4vw, 32px);
}
@media (max-width: 880px) { .rcs-insights { grid-template-columns: 1fr; } }
.rcs-insight {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(22px, 2.4vw, 32px);
  display: flex; flex-direction: column; gap: 18px;
  transition: transform var(--t-med), border-color var(--t-med);
}
.rcs-insight:hover { transform: translateY(-2px); border-color: var(--ink); }
.rcs-insight__head { display: flex; gap: 14px; align-items: center; }
.rcs-insight__num {
  width: 30px; height: 30px; border-radius: 50%;
  background: var(--ink); color: var(--bg);
  display: inline-flex; align-items: center; justify-content: center;
  font-family: var(--mono); font-size: 12px; font-weight: 500;
}
.rcs-insight__icon { width: 28px; height: 28px; color: var(--ink); }
.rcs-insight__icon svg { width: 100%; height: 100%; }
.rcs-insight__title {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(18px, 1.5vw, 22px);
  line-height: 1.2; letter-spacing: -0.01em; color: var(--ink);
}
.rcs-insight__desc { font-size: 14.5px; line-height: 1.55; color: var(--ink-soft); }

/* ---------- 03 Concept ---------- */
.rcs-concept {
  display: grid; grid-template-columns: 0.8fr 1.2fr;
  gap: clamp(40px, 5vw, 80px); align-items: start;
}
@media (max-width: 880px) { .rcs-concept { grid-template-columns: 1fr; } }
.rcs-concept__title {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(28px, 3.2vw, 42px);
  line-height: 1.05; letter-spacing: -0.015em; color: var(--ink);
  margin-bottom: 20px;
}
.rcs-concept__desc {
  font-size: clamp(15px, 1.1vw, 17px);
  line-height: 1.6; color: var(--ink-soft); margin-bottom: 28px;
}
.rcs-checklist { display: grid; gap: 14px; margin-bottom: 32px; padding: 0; }
.rcs-checklist li {
  display: grid; grid-template-columns: 22px 1fr; gap: 14px; align-items: start;
  font-size: 14.5px; line-height: 1.5; color: var(--ink);
}
.rcs-checklist svg { width: 22px; height: 22px; color: var(--ink); flex-shrink: 0; }
.rcs-concept__cta {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 14px; color: var(--ink);
  border-bottom: 1px solid var(--ink);
  padding-bottom: 3px;
  transition: gap var(--t-fast);
}
.rcs-concept__cta:hover { gap: 12px; }

.rcs-screens {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: clamp(14px, 1.5vw, 20px);
}
@media (max-width: 880px) { .rcs-screens { grid-template-columns: 1fr 1fr; } }
.rcs-screen { display: flex; flex-direction: column; gap: 12px; }
.rcs-screen__label {
  font-family: var(--serif);
  font-weight: 400;
  font-size: 15px;
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--ink);
}
.rcs-screen__sub {
  font-size: 11.5px; color: var(--muted);
  font-family: var(--mono); letter-spacing: 0.08em; text-transform: uppercase;
}
.rcs-screen__frame {
  aspect-ratio: 9 / 17;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--bg);
  overflow: hidden;
  padding: 10px 8px 8px;
  display: flex; flex-direction: column; gap: 6px;
}
.rcs-screen__top {
  display: flex; justify-content: space-between;
  font-family: var(--mono); font-size: 9px; color: var(--ink); padding: 0 6px 4px;
}
.rcs-screen__body {
  flex: 1; background: var(--bg-alt); border-radius: 10px; padding: 10px;
  display: flex; flex-direction: column; gap: 8px;
}
.rcs-screen__title { font-size: 10.5px; font-weight: 600; color: var(--ink); }
.rcs-screen__lead { font-size: 9px; color: var(--muted); }
.rcs-screen__card {
  background: var(--bg); border-radius: 8px; padding: 8px;
  font-size: 9px; color: var(--ink-soft);
  display: flex; flex-direction: column; gap: 4px;
}
.rcs-screen__row {
  display: flex; justify-content: space-between; align-items: center; gap: 6px;
}
.rcs-screen__bignum { font-family: var(--serif); font-size: 22px; line-height: 1; color: var(--ink); }
.rcs-screen__pill {
  display: inline-block; background: var(--ink); color: var(--bg);
  border-radius: 999px; padding: 2px 6px; font-size: 7.5px; letter-spacing: 0.06em;
}
.rcs-screen__chart { display: flex; align-items: flex-end; gap: 2px; height: 24px; }
.rcs-screen__chart span {
  flex: 1; background: var(--ink); border-radius: 2px 2px 0 0; opacity: 0.7;
}
.rcs-screen__chart span:nth-child(odd) { opacity: 0.4; }
.rcs-screen__alert {
  background: #F8E6E0; border-radius: 8px; padding: 8px;
  font-size: 9px; color: var(--ink); display: flex; flex-direction: column; gap: 4px;
}
.rcs-screen__alert b { font-size: 10px; }

/* ---------- 04 Principles ---------- */
.rcs-principles {
  display: grid; grid-template-columns: repeat(5, 1fr);
  gap: 1px; background: var(--line);
  border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden;
}
@media (max-width: 1080px) { .rcs-principles { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 540px)  { .rcs-principles { grid-template-columns: 1fr; } }
.rcs-principle {
  background: var(--bg);
  padding: clamp(22px, 2.4vw, 30px);
  display: flex; flex-direction: column; gap: 10px;
}
.rcs-principle__icon { width: 32px; height: 32px; color: var(--ink); margin-bottom: 6px; }
.rcs-principle__icon svg { width: 100%; height: 100%; }
.rcs-principle__title {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(17px, 1.4vw, 20px);
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--ink);
}
.rcs-principle__desc { font-size: 13px; line-height: 1.5; color: var(--muted); }

/* ---------- 05 Methods ---------- */
.rcs-methods {
  display: grid; grid-template-columns: repeat(4, 1fr);
  gap: clamp(14px, 1.6vw, 22px);
}
@media (max-width: 880px) { .rcs-methods { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 480px) { .rcs-methods { grid-template-columns: 1fr; } }
.rcs-method {
  display: flex; gap: 12px; align-items: center;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg);
  transition: border-color var(--t-fast);
}
.rcs-method:hover { border-color: var(--ink); }
.rcs-method__icon { width: 24px; height: 24px; color: var(--ink); flex-shrink: 0; }
.rcs-method__icon svg { width: 100%; height: 100%; }
.rcs-method__label {
  font-family: var(--serif);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--ink);
}

/* ---------- 06 Explorations ---------- */
.rcs-explorations {
  display: grid; grid-template-columns: repeat(5, 1fr);
  gap: clamp(14px, 1.6vw, 22px);
}
@media (max-width: 1080px) { .rcs-explorations { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 540px)  { .rcs-explorations { grid-template-columns: 1fr; } }
.rcs-expl { display: flex; flex-direction: column; gap: 14px; }
.rcs-expl__head h3 {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(17px, 1.4vw, 20px);
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--ink);
  margin-bottom: 6px;
}
.rcs-expl__head p { font-size: 12.5px; color: var(--muted); line-height: 1.45; }
.rcs-expl__media {
  flex: 1;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg);
  aspect-ratio: 5 / 4;
  padding: 16px;
  display: flex; align-items: center; justify-content: center;
  color: var(--ink);
}
.rcs-expl__media svg { width: 100%; height: 100%; max-height: 130px; opacity: 0.92; }

/* ---------- 07 Vision + Publication ---------- */
.rcs-vision-section { padding: clamp(56px, 7vw, 96px) 0; }
.rcs-vision {
  display: grid; grid-template-columns: 1.1fr 1fr;
  gap: clamp(40px, 6vw, 88px); align-items: start;
}
@media (max-width: 880px) { .rcs-vision { grid-template-columns: 1fr; } }
.rcs-vision__quote {
  display: grid; grid-template-columns: 44px 1fr;
  gap: 20px;
}
.rcs-vision__mark {
  font-family: var(--serif); font-size: 64px; line-height: 0.6;
  color: #C9B8A3; padding-top: 12px;
}
.rcs-vision__text {
  font-family: var(--serif); font-style: italic;
  font-size: clamp(20px, 1.8vw, 26px);
  line-height: 1.4; letter-spacing: -0.005em; color: var(--ink);
}
.rcs-pub {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(24px, 2.6vw, 36px);
}
.rcs-pub__head {
  display: flex; align-items: center; gap: 14px; margin-bottom: 16px;
}
.rcs-pub__icon {
  width: 36px; height: 36px; border-radius: 6px; border: 1px solid var(--line);
  display: inline-flex; align-items: center; justify-content: center;
}
.rcs-pub__icon svg { width: 18px; height: 18px; }
.rcs-pub__label {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--muted);
}
.rcs-pub__body { font-size: 14.5px; line-height: 1.55; color: var(--ink-soft); margin-bottom: 18px; }
.rcs-pub__link {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 14px; color: var(--ink);
  border-bottom: 1px solid var(--ink); padding-bottom: 3px;
  transition: gap var(--t-fast);
}
.rcs-pub__link:hover { gap: 12px; }

/* ---------- Decorative botanical ---------- */
.rcs-leaf {
  position: absolute; opacity: 0.5; pointer-events: none;
  color: #B8C5A8;
}
.rcs-leaf--tr { top: -20px; right: -30px; width: 260px; transform: rotate(15deg); }
.rcs-leaf--bl { bottom: -20px; left: -30px; width: 260px; transform: rotate(-160deg); }