/* =========================================================================
   Refined Calculator Page System — runbikecalc editorial cream + copper
   Used by: bike-climb-time-calculator, bike-chain-length-calculator,
            drafting-power-calculator
   ========================================================================= */

.calc-page {
  background: #FAF8F5 !important;
  color: #1A1A1A;
  font-family: 'Source Sans 3', sans-serif;
}

/* Per-page theme accents — terracotta, steel, wine */
.calc-page--climb    { --accent: #C67B4E; --accent-soft: #F7E7D9; --accent-deep: #8F5431; }
.calc-page--chain    { --accent: #4A5568; --accent-soft: #E7EBF0; --accent-deep: #2D3748; }
.calc-page--drafting { --accent: #7C3344; --accent-soft: #F5E3E7; --accent-deep: #551F2D; }

.calc-page main { padding-top: 2rem; padding-bottom: 4.5rem; }

/* ---------- HERO ---------- */
.calc-hero {
  position: relative;
  margin: 1.5rem 0 3rem;
  padding: 0 0 2.5rem;
  border-bottom: 1px solid rgba(26,26,26,0.08);
}
.calc-hero::after {
  content: ''; position: absolute; bottom: -0.5px; right: 0;
  width: 60px; height: 1px; background: var(--accent);
}

.calc-hero__eyebrow {
  display: inline-flex; align-items: center; gap: 0.75rem;
  font-size: 0.7rem; font-weight: 600;
  letter-spacing: 0.22em; text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.25rem;
}
.calc-hero__eyebrow::before {
  content: ''; width: 28px; height: 1px; background: var(--accent);
}

.calc-hero__h1 {
  font-family: 'Playfair Display', serif; font-weight: 500;
  font-size: clamp(2.25rem, 4.5vw, 3.5rem);
  line-height: 1.05; letter-spacing: -0.02em;
  color: #1A1A1A; margin: 0 0 1.1rem;
  max-width: 760px;
}
.calc-hero__h1 em {
  font-style: italic; color: var(--accent); font-weight: 400;
}

.calc-hero__dek {
  font-size: 1.0625rem; line-height: 1.65;
  color: #444; max-width: 640px; margin: 0 0 2rem;
}

.calc-hero__formula {
  display: flex; gap: 1.5rem;
  background: rgba(255,255,255,0.6);
  border: 1px solid rgba(26,26,26,0.08);
  border-left: 3px solid var(--accent);
  padding: 1.1rem 1.4rem;
  border-radius: 0 8px 8px 0;
  max-width: 760px;
}
.calc-hero__formula-label {
  font-size: 0.65rem; font-weight: 700;
  letter-spacing: 0.22em; text-transform: uppercase;
  color: var(--accent);
  flex-shrink: 0; padding-top: 3px; min-width: 96px;
}
.calc-hero__formula-body {
  font-size: 0.95rem; line-height: 1.6; color: #333;
}
.calc-hero__formula-body code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.88em;
  background: rgba(26,26,26,0.045);
  padding: 1px 6px; border-radius: 3px;
}

/* ---------- CALCULATOR FORM ---------- */
.calc-form {
  background: #fff;
  border: 1px solid rgba(26,26,26,0.08);
  border-radius: 16px;
  padding: 2rem 2.25rem;
  margin: 0 0 2rem;
  box-shadow: 0 1px 0 rgba(26,26,26,0.03), 0 14px 36px -20px rgba(26,26,26,0.1);
}
@media (min-width: 768px) { .calc-form { padding: 2.5rem 3rem; } }
@media (max-width: 640px) { .calc-form { padding: 1.5rem 1.25rem; } }

.calc-form__header {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 1rem; margin: 0 0 1.75rem; padding-bottom: 1rem;
  border-bottom: 1px solid rgba(26,26,26,0.08);
}
.calc-form__h2 {
  font-family: 'Playfair Display', serif; font-weight: 500;
  font-size: 1.5rem; letter-spacing: -0.01em; margin: 0;
}
.calc-form__h2-num {
  font-size: 0.65rem; font-weight: 600;
  letter-spacing: 0.22em; color: var(--accent);
}

.calc-form__presets { margin-bottom: 1.75rem; }

.calc-form__preset-label,
.calc-field__label {
  display: block;
  font-size: 0.7rem; font-weight: 700;
  letter-spacing: 0.15em; text-transform: uppercase;
  color: rgba(26,26,26,0.55);
  margin-bottom: 0.55rem;
}

.calc-form__preset-select,
.calc-field__select,
.calc-field__input {
  font-family: 'Source Sans 3', sans-serif;
  font-size: 0.95rem;
  padding: 0.7rem 1rem;
  border: 1px solid rgba(26,26,26,0.18);
  border-radius: 8px;
  background: #fff; color: #1A1A1A;
  transition: border-color .15s, box-shadow .15s, background .15s;
  appearance: none; -webkit-appearance: none;
  width: 100%;
}
.calc-form__preset-select,
.calc-field__select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='14' height='14' viewBox='0 0 16 16'%3E%3Cpath d='M4 6l4 4 4-4' stroke='%231A1A1A' fill='none' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.85rem center;
  padding-right: 2.25rem;
  cursor: pointer;
}
.calc-form__preset-select { min-width: 280px; max-width: 100%; }

.calc-field__select:focus,
.calc-field__input:focus,
.calc-form__preset-select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 22%, transparent);
  background: #fff;
}
.calc-field__input[type="number"] {
  font-feature-settings: 'tnum';
  font-variant-numeric: tabular-nums;
}

.calc-grid {
  display: grid; grid-template-columns: 1fr;
  gap: 1.25rem 1.5rem;
}
@media (min-width: 640px) { .calc-grid { grid-template-columns: 1fr 1fr; } }

.calc-field { display: flex; flex-direction: column; }
.calc-field__help {
  font-size: 0.75rem; color: rgba(26,26,26,0.5);
  line-height: 1.45; margin-top: 0.4rem;
}
.calc-field__group { display: flex; gap: 0.5rem; }
.calc-field__group .calc-field__input { flex: 1; min-width: 0; }
.calc-field__group .calc-field__select {
  flex-shrink: 0; min-width: 82px; width: auto;
  padding-right: 1.85rem;
}

/* Submit */
.calc-submit {
  margin-top: 1.75rem;
  display: inline-flex; align-items: center; gap: 0.75rem;
  background: #1A1A1A; color: #fff;
  font-family: 'Source Sans 3', sans-serif;
  font-size: 0.78rem; font-weight: 600;
  letter-spacing: 0.2em; text-transform: uppercase;
  padding: 0.95rem 1.9rem;
  border: 0; border-radius: 999px;
  cursor: pointer;
  transition: transform .15s, background .15s, box-shadow .15s;
  box-shadow: 0 1px 0 rgba(26,26,26,0.1), 0 10px 24px -12px rgba(26,26,26,0.4);
}
.calc-submit:hover {
  background: var(--accent-deep, var(--accent));
  transform: translateY(-1px);
}
.calc-submit:active { transform: translateY(0); }
.calc-submit__arrow { width: 14px; height: 14px; }

/* ---------- RESULTS ---------- */
.calc-results {
  margin-top: 2.5rem; padding-top: 2rem;
  border-top: 1px solid rgba(26,26,26,0.1);
  animation: calcFadeUp .35s cubic-bezier(.2,.7,.2,1);
}
.calc-results.hidden { display: none; }

.calc-results__header {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 1rem; margin-bottom: 1.5rem;
}
.calc-results__h3 {
  font-family: 'Playfair Display', serif; font-weight: 500;
  font-size: 1.375rem; letter-spacing: -0.01em; margin: 0;
}
.calc-results__tag {
  font-size: 0.65rem; font-weight: 600;
  letter-spacing: 0.2em; text-transform: uppercase;
  color: var(--accent);
}

.calc-results__grid {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: rgba(26,26,26,0.1);
  border: 1px solid rgba(26,26,26,0.1);
  border-radius: 12px; overflow: hidden;
}
@media (min-width: 768px) { .calc-results__grid { grid-template-columns: repeat(4, 1fr); } }

.calc-results__tile {
  background: #fff; padding: 1.35rem 1.25rem;
  display: flex; flex-direction: column; gap: 0.45rem;
  position: relative;
}
.calc-results__tile-label {
  font-size: 0.62rem; font-weight: 700;
  letter-spacing: 0.24em; text-transform: uppercase;
  color: rgba(26,26,26,0.55);
}
.calc-results__tile-value {
  font-family: 'Playfair Display', serif; font-weight: 500;
  font-size: 1.75rem; letter-spacing: -0.02em;
  color: #1A1A1A; line-height: 1.1;
  font-variant-numeric: tabular-nums;
}
.calc-results__tile-unit {
  font-size: 0.72rem; color: rgba(26,26,26,0.5); font-style: italic;
}
.calc-results__tile--primary {
  background: linear-gradient(180deg, var(--accent-soft), #fff);
  grid-column: span 2;
}
@media (min-width: 768px) {
  .calc-results__tile--primary { grid-column: span 2; }
}
.calc-results__tile--primary .calc-results__tile-value {
  font-size: 2.35rem; color: var(--accent-deep, #1A1A1A);
}

.calc-results__context {
  margin-top: 1.2rem;
  padding: 1rem 1.25rem;
  background: rgba(26,26,26,0.03);
  border-left: 3px solid var(--accent);
  border-radius: 0 6px 6px 0;
  font-size: 0.925rem; line-height: 1.6; color: #333;
}

@media (max-width: 640px) {
  .calc-results__tile-value { font-size: 1.5rem; }
  .calc-results__tile--primary .calc-results__tile-value { font-size: 2rem; }
}

/* ---------- PROSE ---------- */
.calc-prose { margin: 3rem 0; max-width: 780px; }
.calc-prose h2 {
  font-family: 'Playfair Display', serif; font-weight: 500;
  font-size: 1.5rem; letter-spacing: -0.01em;
  margin: 2rem 0 1rem; color: #1A1A1A;
}
.calc-prose h2:first-child { margin-top: 0; }
.calc-prose p,
.calc-prose ul,
.calc-prose ol {
  font-size: 1rem; line-height: 1.7;
  color: #333; margin: 0 0 1rem;
}
.calc-prose ul { padding-left: 1.25rem; list-style: none; }
.calc-prose ul li { padding-left: 0.25rem; margin-bottom: 0.5rem; position: relative; }
.calc-prose ul li::before {
  content: ''; position: absolute;
  left: -1.1rem; top: 0.78rem;
  width: 6px; height: 1px; background: var(--accent);
}
.calc-prose strong { color: #1A1A1A; font-weight: 600; }
.calc-prose code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.85em;
  background: rgba(26,26,26,0.045);
  padding: 1px 5px; border-radius: 3px;
}
.calc-prose a {
  color: var(--accent); text-decoration: underline;
  text-decoration-thickness: 1px; text-underline-offset: 3px;
}

/* ---------- FAQ ---------- */
.calc-faq { margin: 3rem 0; }

.calc-faq__header {
  display: flex; align-items: baseline; gap: 1.25rem;
  margin-bottom: 1.25rem; padding-bottom: 0.75rem;
  border-bottom: 1px solid rgba(26,26,26,0.08);
}
.calc-faq__h2 {
  font-family: 'Playfair Display', serif; font-weight: 500;
  font-size: 1.625rem; letter-spacing: -0.01em;
  margin: 0;
}
.calc-faq__tag {
  font-size: 0.65rem; font-weight: 600;
  letter-spacing: 0.22em; text-transform: uppercase;
  color: var(--accent);
  margin-left: auto;
}

.calc-faq__list { display: flex; flex-direction: column; }

.calc-faq__item {
  display: grid; grid-template-columns: 3rem 1fr;
  gap: 0.5rem; padding: 1.1rem 0 1.1rem;
  border-bottom: 1px solid rgba(26,26,26,0.08);
  align-items: start;
}
.calc-faq__item:last-child { border-bottom: 0; }

.calc-faq__num {
  font-family: 'Playfair Display', serif; font-weight: 400;
  font-size: 0.9rem; font-style: italic;
  color: var(--accent); padding-top: 0.35rem;
}

.calc-faq__details { margin: 0; padding: 0; }

.calc-faq__summary {
  list-style: none; cursor: pointer;
  display: flex; justify-content: space-between; align-items: center;
  gap: 1rem;
  font-family: 'Playfair Display', serif; font-weight: 500;
  font-size: 1.05rem; color: #1A1A1A;
  line-height: 1.4; padding: 0.3rem 0;
  transition: color .15s;
}
.calc-faq__summary::-webkit-details-marker { display: none; }
.calc-faq__summary::marker { content: ''; }
.calc-faq__summary:hover { color: var(--accent); }

.calc-faq__chevron {
  flex-shrink: 0; width: 14px; height: 14px;
  transition: transform .25s cubic-bezier(.2,.7,.2,1);
  color: var(--accent);
}
.calc-faq__details[open] .calc-faq__chevron { transform: rotate(45deg); }

.calc-faq__answer {
  margin: 0.65rem 0 0.1rem;
  font-size: 0.975rem; line-height: 1.65; color: #444;
  animation: faqOpen .25s ease-out;
}
@keyframes faqOpen {
  from { opacity: 0; transform: translateY(-3px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ---------- RELATED CALCULATORS ---------- */
.calc-related { margin: 3rem 0 0; }

.calc-related__header {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 1rem; margin-bottom: 1.25rem; padding-bottom: 0.75rem;
  border-bottom: 1px solid rgba(26,26,26,0.08);
}
.calc-related__h2 {
  font-family: 'Playfair Display', serif; font-weight: 500;
  font-size: 1.375rem; letter-spacing: -0.01em; margin: 0;
}
.calc-related__tag {
  font-size: 0.65rem; font-weight: 600;
  letter-spacing: 0.22em; text-transform: uppercase;
  color: var(--accent);
}

.calc-related__grid {
  display: grid; grid-template-columns: 1fr;
  gap: 1px;
  background: rgba(26,26,26,0.08);
  border: 1px solid rgba(26,26,26,0.08);
  border-radius: 12px; overflow: hidden;
}
@media (min-width: 768px) { .calc-related__grid { grid-template-columns: repeat(3, 1fr); } }

.calc-related__card {
  display: flex; flex-direction: column; gap: 0.55rem;
  padding: 1.4rem 1.5rem 1.5rem;
  background: #fff; text-decoration: none;
  border-left: 3px solid transparent;
  transition: background .2s, border-color .2s, transform .2s;
}
.calc-related__card:hover {
  background: #FAF8F5; border-left-color: var(--accent);
  transform: translateY(-1px);
}
.calc-related__card-kicker {
  font-size: 0.62rem; font-weight: 700;
  letter-spacing: 0.24em; text-transform: uppercase;
  color: rgba(26,26,26,0.45);
}
.calc-related__card-title {
  font-family: 'Playfair Display', serif; font-weight: 500;
  font-size: 1.15rem; color: #1A1A1A;
  margin: 0; letter-spacing: -0.01em;
  display: flex; align-items: center; gap: 0.5rem;
}
.calc-related__card-title::after {
  content: '→'; color: var(--accent); font-size: 1rem;
  transition: transform .2s; margin-left: auto;
}
.calc-related__card:hover .calc-related__card-title::after {
  transform: translateX(4px);
}
.calc-related__card-dek {
  font-size: 0.9rem; line-height: 1.55;
  color: rgba(26,26,26,0.65); margin: 0;
}

/* ---------- ANIMATIONS ---------- */
@keyframes calcFadeUp {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: translateY(0); }
}
.calc-page .calc-hero,
.calc-page .calc-form,
.calc-page .calc-faq,
.calc-page .calc-related {
  animation: calcFadeUp .55s cubic-bezier(.2,.7,.2,1) both;
}
.calc-page .calc-hero { animation-delay: .03s; }
.calc-page .calc-form { animation-delay: .12s; }
.calc-page .calc-faq { animation-delay: .22s; }
.calc-page .calc-related { animation-delay: .28s; }

@media (prefers-reduced-motion: reduce) {
  .calc-page .calc-hero,
  .calc-page .calc-form,
  .calc-page .calc-faq,
  .calc-page .calc-related,
  .calc-results { animation: none; }
}