html {
  scroll-behavior: smooth;
}

button,
input {
  font: inherit;
}

.page-container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.5rem 1rem 4rem;
}

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin-bottom: 1.25rem;
  color: var(--text-muted);
  font-size: 0.875rem;
}

.breadcrumb a {
  color: var(--primary-hover);
  font-weight: 600;
  text-decoration: none;
}

.breadcrumb a:hover {
  text-decoration: underline;
}

.calculator-section,
.result-section {
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.calculator-heading {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.5rem;
  background: #ffffff;
  border-bottom: 1px solid var(--border);
}

.heading-icon {
  width: 64px;
  height: 64px;
  flex: 0 0 64px;
  display: grid;
  place-items: center;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
}

.heading-icon img {
  width: 44px;
  height: 44px;
  object-fit: contain;
}

.calculator-heading h1 {
  color: #0a174e;
  font-family: "Basic", serif;
  font-size: clamp(1.55rem, 4vw, 2.1rem);
  line-height: 1.2;
}

.calculator-heading p {
  max-width: 760px;
  margin-top: 0.4rem;
  color: var(--text-muted);
  font-family: "Nunito Sans", sans-serif;
}

.calculator-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(280px, 0.65fr);
  gap: 1.5rem;
  padding: 1.5rem;
}

.calculator-form,
.information-box {
  padding: 1.5rem;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 12px;
}

.form-group + .form-group {
  margin-top: 1.25rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.45rem;
  color: #0a174e;
  font-weight: 700;
}

.input-wrapper {
  position: relative;
}

.input-wrapper input {
  width: 100%;
  min-height: 50px;
  padding: 0.8rem 8.5rem 0.8rem 0.9rem;
  color: #0a174e;
  background: #ffffff;
  border: 1px solid #b7d8ca;
  border-radius: 9px;
  outline: none;
  transition:
    border-color 0.2s ease,
    box-shadow 0.2s ease;
}

.input-wrapper input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.15);
}

.input-wrapper input.input-error {
  border-color: #b91c1c;
  box-shadow: 0 0 0 3px rgba(185, 28, 28, 0.1);
}

.input-suffix {
  position: absolute;
  top: 50%;
  right: 0.9rem;
  transform: translateY(-50%);
  color: var(--primary-hover);
  font-size: 0.82rem;
  font-weight: 700;
  pointer-events: none;
}

.form-message {
  display: none;
  margin-top: 1.25rem;
  padding: 0.8rem;
  color: #b91c1c;
  background: #fef2f2;
  border: 1px solid #fecaca;
  border-radius: 8px;
  font-size: 0.875rem;
  font-weight: 600;
}

.form-message.visible {
  display: block;
}

.button-group {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.primary-button,
.secondary-button {
  min-height: 44px;
  padding: 0.7rem 1.25rem;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 700;
}

.primary-button {
  color: #ffffff;
  background: var(--accent);
  border: 1px solid var(--accent);
}

.primary-button:hover {
  background: var(--primary-hover);
  border-color: var(--primary-hover);
}

.secondary-button {
  color: #0a174e;
  background: #ffffff;
  border: 1px solid #b7d8ca;
}

.secondary-button:hover {
  background: var(--surface);
}

.information-box {
  align-self: start;
}

.information-box ul {
  margin-top: 1rem;
  padding-left: 1.25rem;
  color: var(--text-muted);
  font-size: 0.875rem;
}

.information-box li + li {
  margin-top: 0.4rem;
}

.formula-box {
  margin: 1rem 0;
  padding: 1rem;
  background: var(--surface);
  border-left: 4px solid var(--accent);
  border-radius: 8px;
}

.formula-box span {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--text-muted);
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
}

.formula-box strong {
  color: #0a174e;
  font-size: 1.05rem;
}

.information-note {
  margin-top: 1rem;
  padding-top: 1rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  font-size: 0.875rem;
}

/* Results */

.result-section {
  margin-top: 1.5rem;
  background: #ffffff;
}

.result-heading {
  padding: 1.5rem;
  border-bottom: 1px solid var(--border);
}

.result-heading span {
  display: block;
  margin-bottom: 0.2rem;
  color: var(--primary-hover);
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.result-heading h2 {
  color: #0a174e;
  font-family: "Basic", serif;
  font-size: 1.5rem;
}

.result-list {
  padding: 0 1.5rem;
}

.result-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--border);
}

.result-row:last-child {
  border-bottom: 0;
}

.result-row span {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.result-row strong {
  max-width: 65%;
  color: #0a174e;
  font-size: 0.95rem;
  text-align: right;
  overflow-wrap: anywhere;
}

.result-row.primary-result {
  margin: 0.75rem 0;
  padding: 1rem;
  background: #d1fae5;
  border: 1px solid #6ee7b7;
  border-radius: 9px;
}

.result-row.primary-result span,
.result-row.primary-result strong {
  color: var(--primary-hover);
  font-weight: 800;
}

.calculation-box,
.explanation-box {
  margin: 1.5rem;
  padding: 1.25rem;
  border-radius: 9px;
}

.calculation-box {
  background: var(--surface);
  border-left: 4px solid var(--accent);
}

.explanation-box {
  background: #ffffff;
  border: 1px solid var(--border);
}

.calculation-box h3,
.explanation-box h3 {
  margin-bottom: 0.75rem;
  color: #0a174e;
  font-size: 1.05rem;
}

.calculation-box p,
.explanation-box p {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.7;
  overflow-wrap: anywhere;
}

.explanation-box p + .equation,
.explanation-box .equation + p,
.explanation-box p + p {
  margin-top: 1.25rem;
}

.equation {
  overflow-x: auto;
  padding: 1rem;
  color: #0a174e;
  background: var(--surface);
  border-left: 4px solid var(--accent);
  border-radius: 8px;
  font-family: "Times New Roman", serif;
  font-size: 1.4rem;
  font-weight: 700;
  text-align: center;
  white-space: nowrap;
}

@media (max-width: 950px) {
  .calculator-layout {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 680px) {
  .page-container {
    padding: 1rem 0.75rem 3rem;
  }

  .calculator-heading {
    align-items: flex-start;
    padding: 1rem;
  }

  .heading-icon {
    width: 50px;
    height: 50px;
    flex-basis: 50px;
  }

  .heading-icon img {
    width: 34px;
    height: 34px;
  }

  .calculator-layout {
    padding: 1rem;
  }

  .calculator-form,
  .information-box {
    padding: 1rem;
  }

  .input-wrapper input {
    padding-right: 7.4rem;
  }

  .button-group {
    flex-direction: column;
  }

  .primary-button,
  .secondary-button {
    width: 100%;
  }

  .result-heading {
    padding: 1rem;
  }

  .result-list {
    padding: 0 1rem;
  }

  .result-row {
    align-items: flex-start;
    flex-direction: column;
    gap: 0.3rem;
    padding: 0.85rem 0;
  }

  .result-row strong {
    max-width: 100%;
    text-align: left;
  }

  .result-row.primary-result {
    padding: 1rem;
  }

  .calculation-box,
  .explanation-box {
    margin: 1rem;
    padding: 1rem;
  }

  .equation {
    font-size: 1.05rem;
  }
}