```css
/* =========================================
   CHALLENGE COMPARISON
========================================= */

.rg-challenge-comparison {
  padding: 100px 0;
  background: var(--section-bg);
}

.rg-challenge-comparison .page-center {
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 20px;
}

.rg-challenge-comparison__grid {
  display: grid;
  grid-template-columns: 1fr 1.15fr;
  gap: 80px;
  align-items: center;
}

/* =========================================
   LEFT CONTENT
========================================= */

.rg-challenge-comparison__eyebrow {
  margin-bottom: 20px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--highlight-color);
}

.rg-challenge-comparison__title {
  margin: 0 0 28px;
  font-size: clamp(3rem, 5vw, 4.5rem);
  line-height: 1.05;
  font-weight: 500;
  letter-spacing: -0.03em;
  color: #0f172a;
}

.rg-challenge-comparison__title span {
  color: var(--highlight-color);
}

.rg-challenge-comparison__description {
  max-width: 560px;
  margin-bottom: 36px;
  font-size: 18px;
  line-height: 1.75;
  color: #1d2939;
}

.rg-challenge-comparison__description p:last-child {
  margin-bottom: 0;
}

.rg-challenge-comparison__button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 16px 30px;
  border: 2px solid #0f172a;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 600;
  font-size: 18px;
  color: #0f172a;
  transition: all 0.25s ease;
}

.rg-challenge-comparison__button:hover {
  background: #0f172a;
  color: #ffffff;
}

/* =========================================
   OUTER SHELL
========================================= */

.rg-challenge-comparison__shell {
  height: 920px;
  padding: 48px;
  border: 2px solid transparent;
  border-radius: 28px;
  background: linear-gradient(
    180deg,
    #01051a 0%,
    #03113c 42%,
    #0d6f75 100%
  );
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.18);
  transition: border-color 0.25s ease;
  overflow: hidden;
}

.rg-challenge-comparison__shell:hover {
  border-color: #f26c0c;
}

/* =========================================
   STATES
========================================= */

.rg-challenge-comparison__state-wrapper {
  position: relative;
  height: 100%;
}

.rg-challenge-comparison__state {
  position: absolute;
  inset: 0;
  visibility: hidden;
  opacity: 0;
  pointer-events: none;
}

.rg-challenge-comparison__state.is-active {
  position: relative;
  visibility: visible;
  opacity: 1;
  pointer-events: auto;
}

/* =========================================
   CARD TITLE + SUBTITLE
========================================= */

.rg-challenge-comparison__card-title {
  margin: 0 0 10px;
  font-size: 3.1rem;
  line-height: 1.08;
  font-weight: 500;
  letter-spacing: -0.03em;
  color: #ffffff;
}

.rg-challenge-comparison__card-subtitle {
  margin: 0 0 28px;
  font-size: 1.3rem;
  line-height: 1.45;
  font-weight: 400;
  color: rgba(255, 255, 255, 0.92);
}

/* =========================================
   TOGGLE
========================================= */

.rg-challenge-comparison__toggle {
  display: inline-flex;
  align-items: center;
  padding: 3px;
  margin: 0 0 28px;
  border: 1px solid rgba(255, 255, 255, 0.95);
  border-radius: 999px;
  background: transparent;
}

.rg-challenge-comparison__toggle-btn {
  border: 0;
  background: transparent;
  box-shadow: none;
  outline: none;
  color: #ffffff;
  font-size: 16px;
  font-weight: 500;
  padding: 9px 24px;
  border-radius: 999px;
  cursor: pointer;
  transition: all 0.25s ease;
}

.rg-challenge-comparison__toggle-btn:focus,
.rg-challenge-comparison__toggle-btn:active {
  outline: none;
  box-shadow: none;
}

.rg-challenge-comparison__toggle-btn.is-active[data-target="before"] {
  background: #f26c0c;
  color: #ffffff;
}

.rg-challenge-comparison__toggle-btn.is-active[data-target="after"] {
  background: #59c6ce;
  color: #ffffff;
}

/* =========================================
   INNER CARD
========================================= */

.rg-challenge-comparison__card {
  position: relative;
  overflow: hidden;
  padding: 40px 30px 34px;
  border-radius: 16px;
  border: 1px solid;
  min-height: 465px;
  display: flex;
  flex-direction: column;
}

.rg-challenge-comparison__card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 12px;
}

.rg-challenge-comparison__card--before {
  border-color: #f26c0c;
  background: linear-gradient(
    180deg,
    rgba(165, 111, 72, 0.96) 0%,
    rgba(142, 112, 79, 0.94) 55%,
    rgba(129, 126, 91, 0.92) 100%
  );
}

.rg-challenge-comparison__card--before::before {
  background: #f26c0c;
}

.rg-challenge-comparison__card--after {
  border-color: #59c6ce;
  background: linear-gradient(
    180deg,
    rgba(48, 92, 127, 0.95) 0%,
    rgba(39, 89, 121, 0.94) 55%,
    rgba(27, 131, 139, 0.93) 100%
  );
}

.rg-challenge-comparison__card--after::before {
  background: #59c6ce;
}

/* =========================================
   TIMELINE SECTION
========================================= */

.rg-challenge-comparison__timeline {
  margin: 0 0 36px;
}

.rg-challenge-comparison__timeline-header {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 20px;
}

.rg-challenge-comparison__timeline-icon {
  width: 34px;
  height: 34px;
  flex-shrink: 0;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  font-weight: 700;
  line-height: 1;
}

.rg-challenge-comparison__timeline-icon img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.rg-challenge-comparison__timeline--before .rg-challenge-comparison__timeline-icon {
  border: 2px solid #f26c0c;
  color: #f26c0c;
}

.rg-challenge-comparison__timeline--after .rg-challenge-comparison__timeline-icon {
  border: 2px solid #59c6ce;
  color: #59c6ce;
}

.rg-challenge-comparison__timeline-copy {
  flex: 1;
}

.rg-challenge-comparison__timeline-title {
  margin: 0 0 4px;
  font-size: 1.75rem;
  line-height: 1.15;
  font-weight: 600;
  color: #ffffff;
}

.rg-challenge-comparison__timeline-subtitle {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.45;
  color: rgba(255, 255, 255, 0.78);
}

.rg-challenge-comparison__timeline-track {
  position: relative;
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  margin: 0 auto 10px;
  padding-top: 10px;
  width: calc(100% - 48px);
}

.rg-challenge-comparison__timeline-track::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: rgba(255, 255, 255, 0.6);
}

.rg-challenge-comparison__timeline-step {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.rg-challenge-comparison__timeline-step-label {
  font-size: 11px;
  font-weight: 500;
  color: #ffffff;
  line-height: 1;
}

.rg-challenge-comparison__timeline-step-marker {
  display: block;
}

.rg-challenge-comparison__timeline--before .rg-challenge-comparison__timeline-step-marker {
  width: 24px;
  height: 14px;
  border-radius: 3px 3px 2px 2px;
  background: #f26c0c;
  opacity: 1;
  box-shadow: none;
}

.rg-challenge-comparison__timeline--after .rg-challenge-comparison__timeline-track {
  align-items: center;
  padding-top: 0;
}

.rg-challenge-comparison__timeline--after .rg-challenge-comparison__timeline-track::before {
  bottom: 3px;
  height: 8px;
  border-radius: 999px;
  background: rgba(170, 233, 213, 0.58);
  border: 1px solid rgba(170, 233, 213, 0.85);
}

.rg-challenge-comparison__timeline--after .rg-challenge-comparison__timeline-step-label {
  display: none;
}

.rg-challenge-comparison__timeline--after .rg-challenge-comparison__timeline-step-marker {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #59c6ce;
  box-shadow: 0 0 0 3px rgba(89, 198, 206, 0.15);
  position: relative;
  top: -3px;
}

.rg-challenge-comparison__timeline-labels {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin-top: 8px;
  width: calc(100% - 48px);
  margin-left: auto;
  margin-right: auto;
}

.rg-challenge-comparison__timeline-labels span {
  flex: 1;
  font-size: 12px;
  line-height: 1.3;
  text-align: center;
  color: rgba(255, 255, 255, 0.72);
}

.rg-challenge-comparison__timeline--after .rg-challenge-comparison__timeline-labels {
  justify-content: center;
}

.rg-challenge-comparison__timeline--after .rg-challenge-comparison__timeline-labels span {
  flex: 0 1 auto;
  color: #59c6ce;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* =========================================
   FEATURES
========================================= */

.rg-challenge-comparison__features {
  padding: 0;
  border: 0;
  background: transparent;
}

.rg-challenge-comparison__feature {
  display: flex;
  align-items: flex-start;
  gap: 14px;
}

.rg-challenge-comparison__feature + .rg-challenge-comparison__feature {
  margin-top: 22px;
}

.rg-challenge-comparison__feature-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  font-weight: 700;
  margin-top: 3px;
}

.rg-challenge-comparison__feature.is-before .rg-challenge-comparison__feature-icon {
  background: rgba(242, 108, 12, 0.18);
  color: #f26c0c;
}

.rg-challenge-comparison__feature.is-after .rg-challenge-comparison__feature-icon {
  background: rgba(89, 198, 206, 0.18);
  color: #7de5eb;
}

.rg-challenge-comparison__feature-content {
  flex: 1;
}

.rg-challenge-comparison__feature-title,
.rg-challenge-comparison__feature-content h4 {
  margin: 0 0 4px;
  font-size: 15px;
  line-height: 1.35;
  font-weight: 700;
  font-style: italic;
  color: #ffffff !important;
}

.rg-challenge-comparison__feature-description,
.rg-challenge-comparison__feature-content p {
  margin: 0;
  font-size: 14px;
  line-height: 1.45;
  font-weight: 400;
  color: rgba(255, 255, 255, 0.82) !important;
}

/* =========================================
   TABLET
========================================= */

@media (max-width: 991px) {
  .rg-challenge-comparison {
    padding: 80px 0;
  }

  .rg-challenge-comparison__grid {
    grid-template-columns: 1fr;
    gap: 50px;
  }

  .rg-challenge-comparison__card-title {
    font-size: 2.4rem;
  }

  .rg-challenge-comparison__card-subtitle {
    font-size: 1.1rem;
  }

  .rg-challenge-comparison__timeline-title {
    font-size: 1.45rem;
  }

  .rg-challenge-comparison__card {
    padding: 36px 24px 28px;
  }
  
  .rg-challenge-comparison__button {
    font-size: 16px;
  }
}

/* =========================================
   MOBILE
========================================= */

@media (max-width: 767px) {
  .rg-challenge-comparison {
    padding: 60px 0;
  }

  .rg-challenge-comparison .page-center {
    padding: 0 16px;
  }

  .rg-challenge-comparison__title {
    font-size: clamp(2.3rem, 10vw, 3.5rem);
  }

  .rg-challenge-comparison__description {
    font-size: 16px;
    line-height: 1.7;
  }

  .rg-challenge-comparison__button {
    width: 100%;
    font-size: 14px;
  }

  .rg-challenge-comparison__shell {
    height: auto;
    padding: 24px;
    border-radius: 22px;
    overflow: visible;
  }

  .rg-challenge-comparison__state-wrapper {
    height: auto;
  }

  .rg-challenge-comparison__card-title {
    font-size: 1.9rem;
  }

  .rg-challenge-comparison__card-subtitle {
    font-size: 1rem;
    margin-bottom: 20px;
  }

  .rg-challenge-comparison__toggle {
    margin-bottom: 20px;
  }

  .rg-challenge-comparison__toggle-btn {
    padding: 8px 18px;
    font-size: 14px;
  }

  .rg-challenge-comparison__card {
    min-height: 0;
    padding: 30px 18px 22px;
  }

  .rg-challenge-comparison__timeline {
    margin-bottom: 28px;
  }

  .rg-challenge-comparison__timeline-title {
    font-size: 1.2rem;
  }

  .rg-challenge-comparison__timeline-subtitle {
    font-size: 0.85rem;
  }

  .rg-challenge-comparison__timeline-track,
  .rg-challenge-comparison__timeline-labels {
    width: 100%;
  }

  .rg-challenge-comparison__timeline-labels span {
    font-size: 10px;
  }

  .rg-challenge-comparison__timeline-step-label {
    font-size: 10px;
  }

  .rg-challenge-comparison__feature-title,
  .rg-challenge-comparison__feature-content h4 {
    font-size: 14px;
  }

  .rg-challenge-comparison__feature-description,
  .rg-challenge-comparison__feature-content p {
    font-size: 13px;
  }
}
```