/* ============================================================
   Why it works - research, psychology, benefits, flywheel
   ============================================================ */

/* ---------- research stats ---------- */
.research-band { background: var(--paper-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.research-cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(24px, 4vw, 48px);
  margin-top: 46px;
}
.research-col h3 {
  font-size: 1.05rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 20px;
}
.research-col h3 .tag {
  font: 700 0.68rem/1 var(--font-head);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--violet);
  background: var(--grad-soft);
  padding: 6px 12px;
  border-radius: 99px;
}
.stat-cards { display: flex; flex-direction: column; gap: 14px; }
.stat-card {
  display: flex;
  align-items: center;
  gap: 20px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}
.stat-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.stat-card .pct {
  font: 800 2.1rem/1 var(--font-head);
  min-width: 96px;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.stat-card p { font-size: 0.92rem; line-height: 1.55; color: var(--ink-soft); }
.research-note { margin-top: 20px; font-size: 0.82rem; color: var(--ink-dim); }

/* ---------- science two-up (CMU + Ohio State) ---------- */
.science-cols {
  display: grid;
  grid-template-columns: 1fr 1px 1fr;
  gap: clamp(24px, 4vw, 56px);
  align-items: start;
  margin-top: 46px;
}
.science-divider { background: linear-gradient(180deg, transparent, var(--line) 20%, var(--line) 80%, transparent); height: 100%; }
.science-col { text-align: center; }
.science-col h3 {
  font-size: clamp(1.15rem, 2vw, 1.45rem);
  font-weight: 800;
  line-height: 1.45;
}
.science-col h3 u { text-decoration-thickness: 3px; text-underline-offset: 5px; }
.science-col h3 .hl { color: var(--blue); }
.science-col .grad-text { display: inline; }
.science-col .src {
  margin-top: 16px;
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--ink-dim);
  max-width: 420px;
  margin-left: auto;
  margin-right: auto;
}

/* ---------- friend-finder calculator ---------- */
.calc-band { text-align: center; }
.calc {
  max-width: 760px;
  margin: 40px auto 0;
}
.calc .slider-wrapper { position: relative; padding-top: 46px; }
.calc input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 8px;
  border-radius: 99px;
  background: linear-gradient(90deg, rgba(74,114,255,.25), rgba(191,72,255,.25));
  outline: none;
}
.calc input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 22px; height: 22px;
  border-radius: 50%;
  background: var(--grad);
  border: 3px solid #fff;
  box-shadow: 0 4px 14px rgba(107, 93, 255, 0.5);
  cursor: grab;
  transition: box-shadow 0.2s ease;
}
.calc input[type="range"]::-webkit-slider-thumb:hover { box-shadow: 0 0 0 8px rgba(107, 93, 255, 0.15); }
.calc input[type="range"]::-moz-range-thumb {
  width: 22px; height: 22px;
  border-radius: 50%;
  background: #7c5cff;
  border: 3px solid #fff;
  box-shadow: 0 4px 14px rgba(107, 93, 255, 0.5);
  cursor: grab;
}
.calc-tooltip {
  position: absolute;
  top: 0;
  transform: translateX(-50%);
  background: var(--grad);
  color: #fff;
  font: 800 1.05rem/1 var(--font-head);
  padding: 10px 16px;
  border-radius: 10px;
  min-width: 84px;
  box-shadow: 0 8px 20px rgba(107, 93, 255, 0.4);
}
.calc-tooltip::after {
  content: "";
  position: absolute;
  left: 50%; bottom: -6px;
  transform: translateX(-50%);
  border: 6px solid transparent;
  border-top-color: #9052f8;
  border-bottom: none;
}
.calc-note { display: block; margin-top: 14px; font-size: 0.95rem; color: var(--ink-dim); }
.calc-readout {
  margin-top: 26px;
  font-size: clamp(1.3rem, 2.6vw, 1.8rem);
  line-height: 1.5;
  color: var(--ink-soft);
  font-family: var(--font-head);
}
.calc-readout strong { font-weight: 800; }
.calc-sub { margin-top: 12px; font-size: 0.95rem; color: var(--ink-dim); }
.calc-sub b { color: var(--ink); }

/* ---------- the question band ---------- */
.question-band {
  background: var(--grad);
  color: #fff;
  text-align: center;
  padding: clamp(36px, 4.5vw, 58px) 24px;
}
.question-band .soo { font: 800 1.15rem var(--font-head); margin-bottom: 14px; opacity: 0.95; }
.question-band h2 { font-size: clamp(1.5rem, 3.2vw, 2.3rem); font-weight: 600; max-width: 900px; margin: 0 auto; line-height: 1.4; }
.question-band h2 u { text-underline-offset: 6px; text-decoration-thickness: 3px; }

/* ---------- psychology cards ---------- */
.psy-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 46px;
}
.psy-card {
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: #fff;
  padding: 30px 26px;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}
.psy-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.psy-card::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: var(--grad);
  opacity: 0;
  transition: opacity 0.25s ease;
}
.psy-card:hover::before { opacity: 1; }
.psy-card h3 { font-size: 1.05rem; font-weight: 800; margin-bottom: 10px; }
.psy-card .term { font: 700 0.68rem/1 var(--font-head); letter-spacing: 0.1em; text-transform: uppercase; color: var(--violet); display: block; margin-bottom: 8px; }
.psy-card p { font-size: 0.9rem; line-height: 1.65; color: var(--ink-soft); }

/* ---------- benefits (members vs community) ---------- */
.benefit-band { background: var(--deep); color: #fff; }
.benefit-band .section-title { color: #fff; }
.benefit-band .section-sub { color: rgba(255, 255, 255, 0.7); }
.benefit-band .eyebrow { color: #cabdff; }
.benefit-cols { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(20px, 3vw, 36px); margin-top: 46px; }
.benefit-col {
  border-radius: var(--radius-lg);
  border: 1px solid rgba(255, 255, 255, 0.1);
  background: rgba(255, 255, 255, 0.04);
  padding: clamp(24px, 3.5vw, 40px);
}
.benefit-col > h3 {
  font-size: 1.2rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 24px;
}
.benefit-col > h3 span { font-size: 1.5rem; }
.benefit {
  display: flex;
  gap: 14px;
  padding: 16px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}
.benefit .b-check {
  flex-shrink: 0;
  width: 26px; height: 26px;
  border-radius: 50%;
  background: rgba(52, 211, 153, 0.15);
  border: 1px solid rgba(52, 211, 153, 0.4);
  color: #6ee7b7;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.75rem;
  font-weight: 800;
}
.benefit h4 { font-size: 0.98rem; font-weight: 700; }
.benefit p { margin-top: 4px; font-size: 0.86rem; line-height: 1.6; color: rgba(255, 255, 255, 0.6); }

/* ---------- flywheel ---------- */
.flywheel-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(28px, 5vw, 64px);
  align-items: center;
  margin-top: 20px;
}
.flywheel-stage { position: relative; aspect-ratio: 1/1; max-width: 460px; margin: 0 auto; width: 100%; }
.flywheel-ring {
  position: absolute;
  inset: 8%;
  border-radius: 50%;
  border: 2px dashed rgba(107, 93, 255, 0.35);
  animation: ring-spin 40s linear infinite;
}
@keyframes ring-spin { to { transform: rotate(360deg); } }
.flywheel-core {
  position: absolute;
  inset: 33%;
  border-radius: 50%;
  background: var(--grad);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  font: 800 clamp(0.85rem, 1.6vw, 1.05rem) var(--font-head);
  box-shadow: 0 16px 44px rgba(107, 93, 255, 0.45);
  padding: 18px;
  line-height: 1.35;
}
.fly-node {
  position: absolute;
  width: 122px;
  transform: translate(-50%, -50%);
  text-align: center;
  transition: transform 0.3s ease;
}
.fly-node .n-ico {
  width: 58px; height: 58px;
  margin: 0 auto 8px;
  border-radius: 50%;
  background: #fff;
  border: 1.5px solid var(--line);
  box-shadow: var(--shadow-md);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.45rem;
  transition: all 0.3s ease;
}
.fly-node b { font: 700 0.8rem/1.25 var(--font-head); color: var(--ink); display: block; }
.fly-node.lit .n-ico {
  border-color: transparent;
  background: var(--grad);
  box-shadow: 0 10px 26px rgba(107, 93, 255, 0.5);
  transform: scale(1.12);
}
.flywheel-copy .lead { margin-top: 18px; font-size: 1.02rem; line-height: 1.75; color: var(--ink-soft); }
.flywheel-copy .lead b { color: var(--ink); }

/* ---------- responsive ---------- */
@media (max-width: 960px) {
  .research-cols { grid-template-columns: 1fr; }
  .science-cols { grid-template-columns: 1fr; }
  .science-divider { display: none; }
  .psy-grid { grid-template-columns: 1fr; }
  .benefit-cols { grid-template-columns: 1fr; }
  .flywheel-grid { grid-template-columns: 1fr; }
}

.fly-node .n-ico svg { width: 24px; height: 24px; }
.fly-node .n-ico { color: var(--blue); }
.fly-node.lit .n-ico { color: #fff; }

@media (max-width: 560px) {
  /* the flywheel nodes sit at left:6% and left:94%; at phone widths a 122px
     node hung off both edges and pushed the page sideways */
  .flywheel-stage { max-width: 300px; }
  .fly-node { width: 92px; }
  .fly-node b { font-size: 0.7rem; line-height: 1.2; }
  .fly-node .n-ico { width: 44px; height: 44px; margin-bottom: 6px; }
  .fly-node .n-ico svg { width: 19px; height: 19px; }
}

@media (max-width: 380px) {
  /* nodes sit at 6%/94% of the stage, so the stage itself has to shrink faster
     than the viewport for their outer halves to stay on screen */
  .flywheel-stage { max-width: 250px; }
  .fly-node { width: 84px; }
}