#race-time-estimator {
  width: 100%;
  box-sizing: border-box;
  padding: 14px;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  color: #111827;
}

/* Card container*/
#race-time-estimator .rte-card{
  width: 100%;
  max-width: 560px;
  margin: 0 auto;
  padding: 14px;
  box-sizing: border-box;
  border-radius: 14px;
  background: #ffffff;
  border: 1px solid #e5e7eb;
}

/* Rows stack nicely on mobile */
#race-time-estimator .rte-row{
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
  margin-bottom: 12px;
}

#race-time-estimator .rte-label{
  font-size: 14px;
  font-weight: 600;
}

/* Inputs should be big enough to tap */
#race-time-estimator .rte-select,
#race-time-estimator .rte-time-input{
  font-size: 16px; /* prevents iOS zoom */
  height: 44px;    /* good tap target */
  border-radius: 12px;
  border: 1px solid #d1d5db;
  padding: 0 12px;
  box-sizing: border-box;
  background: #fff;
  color: inherit;
}

/* Time group */
#race-time-estimator .rte-time{
  display: flex;
  align-items: center;
  gap: 8px;
}

#race-time-estimator .rte-time-input{
  width: clamp(3.2rem, 18vw, 4.4rem);
  text-align: center;
  padding: 0;
}

#race-time-estimator .rte-sep{
  font-weight: 700;
  opacity: 0.7;
}

/* Button */
#race-time-estimator .rte-btn{
  width: 100%;
  height: 46px;
  border: 0;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 700;
  background: #111827;
  color: #ffffff;
}

/* Output area */
#race-time-estimator .rte-result{
  margin-top: 14px;
  padding: 14px 12px;
  border-radius: 14px;
  border: 1px solid #e5e7eb;
  background: #ececec;
  text-align: center;
}

#race-time-estimator .rte-result-title{
  font-size: 15px;
  font-weight: 700;
  opacity: 0.75;
  margin-bottom: 8px;
}

#race-time-estimator .rte-result-value{
  font-size: clamp(13px, 5.5vw, 17px);
  font-weight: 800;
  letter-spacing: 0.2px;
  line-height: 1.2;
}


/* Desktop: label + control on one line */
@media (min-width: 768px){
  #race-time-estimator .rte-row{
    grid-template-columns: 140px 1fr;
    align-items: center;
  }
  #race-time-estimator .rte-btn{
  width: 100%;
  height: 46px;
  border: 0;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 700;
  background: #111827;
  color: #ffffff;
}
  /* Inputs & select hover */
  #race-time-estimator .rte-select:hover,
  #race-time-estimator .rte-time-input:hover {
    background-color: #f3f4f6; /* light neutral grey */
  }

  @media (hover: hover) and (pointer: fine) {
  #race-time-estimator .rte-btn:hover {
    background-color: #1f2937; /* slightly lighter than base */
    transform: translateY(-1px);
  }
}
}

/* Smooth transitions (applies everywhere, harmless on mobile) */
#race-time-estimator .rte-select,
#race-time-estimator .rte-time-input,
#race-time-estimator .rte-btn {
  transition: background-color 0.15s ease, color 0.15s ease,
              transform 0.12s ease;
}

/* --- Micro-interactions: button press + smooth transitions --- */
#race-time-estimator .rte-btn{
  transition: transform 120ms ease, filter 120ms ease, background-color 150ms ease;
  transform: translateZ(0);
}

/* Works on desktop + mobile (tap) */
#race-time-estimator .rte-btn:active{
  transform: scale(0.98);
  filter: brightness(0.95);
}

/* Optional: subtle hover lift for desktop (keep text white) */
@media (hover: hover) and (pointer: fine) {
  #race-time-estimator .rte-btn:hover {
    filter: brightness(1.05);
  }
}

/* --- Output pop animation --- */
#race-time-estimator .rte-result-value{
  transition: transform 160ms ease, opacity 160ms ease;
}

#race-time-estimator .rte-result-value.rte-pop{
  transform: translateY(-2px) scale(1.02);
}

/* --- Invalid shake animation (apply to the time group) --- */
#race-time-estimator .rte-time.rte-shake{
  animation: rte-shake 300ms ease;
}

@keyframes rte-shake{
  0%   { transform: translateX(0); }
  20%  { transform: translateX(-6px); }
  40%  { transform: translateX(6px); }
  60%  { transform: translateX(-4px); }
  80%  { transform: translateX(4px); }
  100% { transform: translateX(0); }
}

/* --- Disabled button appearance during "计算中..." --- */
#race-time-estimator .rte-btn:disabled{
  cursor: not-allowed;
  opacity: 0.85;
  filter: none;
  transform: none;
}

/* Respect reduced motion */
@media (prefers-reduced-motion: reduce){
  #race-time-estimator .rte-btn,
  #race-time-estimator .rte-result-value{
    transition: none !important;
  }
  #race-time-estimator .rte-time.rte-shake{
    animation: none !important;
  }
}

/* Navigation styling */

.tool-nav {
  max-width: 900px;
  margin: 0 auto 16px;
  padding: 12px 20px 0;
  
}

.tool-back {
  font-size: 1.0em;
  color: #2563eb;
  text-decoration: none;

}

.tool-back:hover {
  text-decoration: underline;
}