.calculation-home {
    min-height: calc(100vh - var(--header-height) - 2.4rem);
    padding: 1.5rem 1.5rem 2rem;
}

.intro {
    margin-bottom: 1.5rem;
}

.section-label {
    color: var(--primary);
    font-size: .75rem;
    font-weight: 700;
    letter-spacing: .1em;
    margin-bottom: .35rem;
    text-transform: uppercase;
}

.intro h1 {
    color: #1d2939;
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: .35rem;
}

.intro-description {
    color: #667085;
    margin: 0;
    max-width: 42rem;
}

.formula-search {
    color: #475467;
    display: block;
    font-size: .76rem;
    font-weight: 700;
    letter-spacing: .08em;
    margin-bottom: 1.25rem;
    max-width: 34rem;
    text-transform: uppercase;
}

.formula-search-control {
    align-items: center;
    background: #fff;
    border: 1px solid #d0d5dd;
    border-radius: .55rem;
    display: flex;
    gap: .62rem;
    margin-top: .42rem;
    padding: 0 .72rem;
    transition: border-color .15s ease, box-shadow .15s ease;
}

.formula-search-control:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 0 .15rem rgba(0, 123, 255, .16);
}

.formula-search-icon {
    color: #98a2b3;
    fill: none;
    flex: 0 0 auto;
    height: 1.05rem;
    stroke: currentColor;
    stroke-linecap: round;
    stroke-linejoin: round;
    stroke-width: 1.75;
    width: 1.05rem;
}

.formula-search-control input {
    background: transparent;
    border: 0;
    color: #344054;
    flex: 1;
    font-size: .92rem;
    padding: .7rem 0;
}

.formula-search-control input:focus {
    outline: 0;
}

.category-grid {
    display: grid;
    gap: 1.1rem;
    grid-template-columns: repeat(2, minmax(280px, 1fr));
}

.category-card {
    background: linear-gradient(132deg, #fff 0%, #fff 58%, var(--category-tint, #f5faff) 100%);
    border: 1px solid #eaecf0;
    border-radius: .9rem;
    box-shadow: 0 2px 8px rgba(16, 24, 40, .04);
    min-height: 11.5rem;
    overflow: hidden;
    padding: 1.25rem 1.3rem;
    position: relative;
}

.category-option {
    --category-accent: #1b98d0;
    --category-accent-rgb: 27, 152, 208;
    --category-tint: #eef8fd;
    cursor: pointer;
    font-family: inherit;
    text-align: left;
    transition: border-color .18s ease, box-shadow .18s ease, transform .18s ease;
    width: 100%;
}

.category-option.pipes {
    --category-accent: #1479bd;
    --category-accent-rgb: 20, 121, 189;
    --category-tint: #eef7fe;
}

.category-option.hydraulics {
    --category-accent: #12a1bc;
    --category-accent-rgb: 18, 161, 188;
    --category-tint: #edfbfc;
}

.category-option.directional {
    --category-accent: #6d61c4;
    --category-accent-rgb: 109, 97, 196;
    --category-tint: #f4f1ff;
}

.category-option.well {
    --category-accent: #d77a2b;
    --category-accent-rgb: 215, 122, 43;
    --category-tint: #fff7ee;
}

.category-option.cementing {
    --category-accent: #248b71;
    --category-accent-rgb: 36, 139, 113;
    --category-tint: #eefaf6;
}

.category-option:hover,
.category-option:focus-visible {
    border-color: rgba(var(--category-accent-rgb), .35);
    box-shadow: 0 10px 24px rgba(16, 24, 40, .09);
    outline: none;
    transform: translateY(-2px);
}

.category-count {
    background: rgba(var(--category-accent-rgb), .09);
    border-radius: 999px;
    color: var(--category-accent);
    display: inline-flex;
    font-size: .76rem;
    font-weight: 700;
    padding: .32rem .7rem;
    position: relative;
    z-index: 1;
}

.category-heading {
    align-items: flex-start;
    display: flex;
    gap: .8rem;
    margin-bottom: 1.1rem;
    max-width: calc(100% - 5.3rem);
    position: relative;
    z-index: 1;
}

.category-icon {
    align-items: center;
    background: rgba(var(--category-accent-rgb), .12);
    border-radius: .6rem;
    color: var(--category-accent);
    display: inline-flex;
    font-size: .9rem;
    font-weight: 700;
    height: 2.5rem;
    justify-content: center;
    min-width: 2.5rem;
}

.category-background {
    bottom: -.65rem;
    color: var(--category-accent);
    height: 8.3rem;
    opacity: .17;
    pointer-events: none;
    position: absolute;
    right: -.6rem;
    transition: opacity .18s ease, transform .18s ease;
    width: 12rem;
}

.category-background svg {
    display: block;
    fill: none;
    height: 100%;
    stroke: currentColor;
    stroke-linecap: round;
    stroke-linejoin: round;
    stroke-width: 3;
    width: 100%;
}

.category-option:hover .category-background,
.category-option:focus-visible .category-background {
    opacity: .25;
    transform: translate(-.15rem, -.15rem) scale(1.02);
}

.category-heading h2 {
    color: #1d2939;
    font-size: 1.05rem;
    font-weight: 700;
    margin: .1rem 0 .25rem;
}

.category-heading p {
    color: #667085;
    font-size: .87rem;
    line-height: 1.35;
    margin: 0;
}

.strategy-list {
    display: flex;
    flex-direction: column;
    gap: .75rem;
}

.strategy-item {
    background: #f8fafc;
    border-radius: .55rem;
    padding: .8rem .9rem;
}

.strategy-title {
    align-items: center;
    display: flex;
    gap: .55rem;
    justify-content: space-between;
}

.strategy-title h3 {
    color: #344054;
    font-size: .92rem;
    font-weight: 700;
    margin: 0 0 .35rem;
}

.strategy-item p {
    color: #667085;
    font-size: .8rem;
    line-height: 1.35;
    margin: 0 0 .6rem;
}

.strategy-notation {
    background: #fff;
    border: 1px solid #eaecf0;
    border-radius: .42rem;
    color: #344054;
    font-family: Georgia, "Times New Roman", serif;
    font-size: 1.12rem;
    margin-bottom: .65rem;
    padding: .48rem .6rem;
    text-align: center;
}

.draw-badge {
    background: #e6f4ff;
    border-radius: 999px;
    color: var(--primary);
    font-size: .68rem;
    font-weight: 700;
    padding: .18rem .48rem;
}

.parameter-list {
    display: flex;
    flex-wrap: wrap;
    gap: .35rem;
}

.parameter-chip {
    background: #fff;
    border: 1px solid #eaecf0;
    border-radius: 999px;
    color: #475467;
    font-size: .72rem;
    padding: .2rem .48rem;
}

.parameter-chip b {
    color: #344054;
    font-family: Georgia, "Times New Roman", serif;
    margin-right: .12rem;
}

.parameter-chip strong {
    color: var(--primary);
    font-weight: 700;
    margin-left: .2rem;
}

.constant-chip {
    background: #f0f7ff;
}

.calculation-link {
    align-items: center;
    color: var(--primary);
    display: inline-flex;
    font-size: .8rem;
    font-weight: 700;
    margin-top: .8rem;
}

.calculation-link::after {
    content: ">";
    margin-left: .4rem;
}

.calculation-link:hover {
    color: #0056b3;
    text-decoration: none;
}

.formula-results-header {
    align-items: baseline;
    display: flex;
    flex-wrap: wrap;
    gap: .5rem 1rem;
    margin-bottom: 1rem;
}

.category-back {
    background: transparent;
    border: 0;
    margin: 0;
    padding: 0;
    width: 100%;
}

.formula-results-header h2 {
    color: #1d2939;
    font-size: 1.2rem;
    font-weight: 700;
    margin: 0;
}

.formula-results-header p {
    color: #667085;
    font-size: .8rem;
    margin: 0;
}

.formula-results {
    display: grid;
    gap: 1rem;
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.formula-card {
    background: #fff;
    border: 1px solid #eaecf0;
    border-radius: .75rem;
    box-shadow: 0 2px 8px rgba(16, 24, 40, .04);
    display: flex;
    flex-direction: column;
    padding: 1.4rem 1.55rem 1.25rem;
}

.formula-card-heading {
    align-items: flex-start;
    display: flex;
    gap: 1rem;
}

.formula-card-icon {
    align-items: center;
    background: #25a6df;
    border-radius: .28rem;
    color: #fff;
    display: flex;
    font-size: 1.6rem;
    height: 3rem;
    justify-content: center;
    min-width: 3rem;
}

.formula-card-heading h3 {
    color: #344054;
    font-size: .94rem;
    font-weight: 600;
    margin: .45rem 0 .32rem;
    text-transform: uppercase;
}

.formula-card-heading p {
    color: #667085;
    font-size: .78rem;
    line-height: 1.35;
    margin: 0;
}

.formula-card-expression {
    color: #344054;
    font-size: 1.65rem;
    margin: 1rem 0 .95rem;
    min-height: 5rem;
    overflow-x: auto;
    overflow-y: visible;
    padding: .65rem 1rem .85rem;
    text-align: center;
}

.formula-card-parameters {
    color: #667085;
    display: flex;
    flex-direction: column;
    flex: 1;
    font-size: .82rem;
    gap: .45rem;
    list-style: none;
    margin: 0 0 1rem;
    padding: 0 0 0 3.9rem;
}

.formula-card-parameters li {
    align-items: baseline;
    display: flex;
    gap: .34rem;
}

.formula-card-parameters li::before {
    color: #98a2b3;
    content: ">";
    margin-right: .2rem;
}

.formula-card-parameters small {
    color: #667085;
    font-size: .73rem;
    margin-left: .12rem;
}

.formula-calculate-button {
    align-items: center;
    align-self: flex-end;
    background: var(--primary);
    border-radius: .42rem;
    color: #fff;
    display: inline-flex;
    font-size: .82rem;
    font-weight: 700;
    gap: .45rem;
    padding: .55rem 1.15rem;
}

.calculator-button-icon {
    fill: none;
    flex: 0 0 auto;
    height: 1.05rem;
    stroke: currentColor;
    stroke-linecap: round;
    stroke-linejoin: round;
    stroke-width: 1.7;
    width: 1.05rem;
}

.formula-calculate-button:hover {
    background: #0069d9;
    color: #fff;
    text-decoration: none;
}

.formula-empty {
    background: #fff;
    border: 1px solid #eaecf0;
    border-radius: .75rem;
    color: #667085;
    max-width: 34rem;
    padding: 1.2rem;
}

.formula-empty h3 {
    color: #344054;
    font-size: 1rem;
    margin-bottom: .35rem;
}

.formula-empty p {
    font-size: .85rem;
    margin: 0;
}

.calculation-page {
    min-height: calc(100vh - var(--header-height) - 2.4rem);
    padding: 1.5rem 1.5rem 2rem;
}

.calculation-header {
    margin-bottom: 1.35rem;
}

.back-link {
    color: var(--primary);
    display: inline-block;
    font-size: .83rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.calculation-header h1,
.calculation-not-found h1 {
    color: #1d2939;
    font-size: 1.8rem;
    font-weight: 700;
    margin: .3rem 0 .35rem;
}

.calculation-description {
    color: #667085;
    margin: 0;
    max-width: 46rem;
}

.formula-notation {
    background: #fff;
    border: 1px solid #eaecf0;
    border-radius: .75rem;
    box-shadow: 0 2px 8px rgba(16, 24, 40, .04);
    margin-top: 1.15rem;
    max-width: 46rem;
    padding: 1rem 1.15rem;
}

.formula-notation-title {
    color: var(--primary);
    font-size: .72rem;
    font-weight: 700;
    letter-spacing: .1em;
    margin: 0 0 .7rem;
    text-transform: uppercase;
}

.formula-expression {
    border-bottom: 1px solid #eaecf0;
    color: #344054;
    font-family: Georgia, "Times New Roman", serif;
    font-size: 1.65rem;
    margin-bottom: .85rem;
    min-height: 5rem;
    overflow-x: auto;
    overflow-y: visible;
    padding: .65rem 1rem 1rem;
    text-align: center;
}

.formula-card-expression mjx-container[display="true"],
.formula-expression mjx-container[display="true"] {
    display: inline-block !important;
    margin: .35rem auto !important;
    min-width: max-content;
    padding: 0 .2rem;
}

.math-expression {
    visibility: hidden;
}

.math-expression.math-ready {
    visibility: visible;
}

.formula-parameters {
    color: #667085;
    display: flex;
    flex-direction: column;
    font-size: .82rem;
    gap: .42rem;
    list-style: none;
    margin: 0;
    padding: 0;
}

.formula-parameters li {
    align-items: baseline;
    display: flex;
    gap: .36rem;
}

.formula-parameters li::before {
    color: #98a2b3;
    content: ">";
    margin-right: .2rem;
}

.formula-symbol {
    color: #344054;
    font-size: .96rem;
    min-width: 2.5rem;
}

.formula-parameters small {
    background: #f0f7ff;
    border-radius: 999px;
    color: var(--primary);
    font-size: .68rem;
    font-weight: 700;
    margin-left: .25rem;
    padding: .12rem .38rem;
}

.calculation-layout {
    align-items: start;
    display: grid;
    gap: 1.1rem;
    grid-template-columns: minmax(280px, 390px) minmax(320px, 1fr);
}

.calculation-panel {
    background: #fff;
    border: 1px solid #eaecf0;
    border-radius: .75rem;
    box-shadow: 0 2px 8px rgba(16, 24, 40, .04);
    padding: 1.2rem;
}

.calculation-panel h2 {
    color: #1d2939;
    font-size: 1.08rem;
    font-weight: 700;
    margin-bottom: .35rem;
}

.panel-description {
    color: #667085;
    font-size: .84rem;
    margin: 0 0 1.1rem;
}

.parameter-field {
    color: #344054;
    font-size: .86rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.required-mark {
    color: #d92d20;
    margin-left: .14rem;
}

.value-input {
    align-items: stretch;
    background: #fff;
    border: 1px solid #d0d5dd;
    border-radius: .45rem;
    display: flex;
    margin-top: .42rem;
    overflow: hidden;
    transition: border-color .15s ease, box-shadow .15s ease;
}

.value-input:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 0 .15rem rgba(0, 123, 255, .16);
}

.value-input.is-invalid {
    background: #fffafa;
    border-color: #f04438;
}

.value-input.is-invalid:focus-within {
    border-color: #f04438;
    box-shadow: 0 0 0 .15rem rgba(240, 68, 56, .14);
}

.value-input.is-invalid input,
.value-input.is-invalid .unit-selector {
    background: #fffafa;
}

.unit-selector {
    appearance: none;
    background: #fff;
    border: 0;
    color: var(--primary);
    font-size: .9rem;
    font-weight: 700;
    min-width: 4.25rem;
    padding: .2rem .7rem;
    text-align: center;
}

.unit-selector:focus {
    outline: none;
}

.parameter-field input {
    border: 0;
    color: #344054;
    flex: 1;
    font-size: .95rem;
    min-width: 0;
    padding: .62rem .72rem;
}

.parameter-field input:focus {
    outline: none;
}

.parameter-field small {
    color: #667085;
    display: block;
    font-size: .74rem;
    font-weight: 400;
    margin-top: .32rem;
}

.field-error {
    color: #d92d20;
    font-size: .74rem;
    font-weight: 600;
    margin: .32rem 0 0;
}

.parameter-group {
    background: #f8fafc;
    border: 1px solid #eaecf0;
    border-radius: .7rem;
    margin: 1.05rem 0;
    padding: .85rem;
}

.parameter-group-heading {
    align-items: flex-start;
    display: flex;
    gap: .85rem;
    justify-content: space-between;
    margin-bottom: .8rem;
}

.parameter-group-heading h3 {
    color: #1d2939;
    font-size: .95rem;
    font-weight: 700;
    margin: 0 0 .2rem;
}

.parameter-group-heading p {
    color: #667085;
    font-size: .78rem;
    line-height: 1.35;
    margin: 0;
}

.parameter-group-add,
.parameter-group-remove {
    border-radius: .42rem;
    cursor: pointer;
    font-size: .76rem;
    font-weight: 700;
    padding: .4rem .7rem;
}

.parameter-group-add {
    background: var(--primary);
    border: 1px solid var(--primary);
    color: #fff;
}

.parameter-group-remove {
    background: #fff;
    border: 1px solid #d0d5dd;
    color: #475467;
}

.parameter-group-remove:disabled {
    cursor: not-allowed;
    opacity: .45;
}

.parameter-group-row {
    background: #fff;
    border: 1px solid #eaecf0;
    border-radius: .6rem;
    padding: .75rem;
}

.parameter-group-row + .parameter-group-row {
    margin-top: .75rem;
}

.parameter-group-row-header {
    align-items: center;
    display: flex;
    justify-content: space-between;
    margin-bottom: .7rem;
}

.parameter-group-row-header strong {
    color: #344054;
    font-size: .82rem;
}

.parameter-group-fields {
    display: grid;
    gap: .75rem;
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.calculate-button {
    align-items: center;
    background: var(--primary);
    border: 1px solid var(--primary);
    border-radius: .45rem;
    color: #fff;
    display: inline-flex;
    font-weight: 700;
    gap: .45rem;
    justify-content: center;
    padding: .62rem 1.1rem;
    width: 100%;
}

.calculate-button:hover {
    background: #0069d9;
    border-color: #0062cc;
}

.calculation-error {
    background: #fff2f2;
    border: 1px solid #fecdca;
    border-radius: .4rem;
    color: #b42318;
    font-size: .8rem;
    margin-bottom: .85rem;
    padding: .55rem .65rem;
}

.output-panels {
    display: flex;
    flex-direction: column;
    gap: 1.1rem;
}

.empty-result {
    color: #667085;
    font-size: .86rem;
    margin: .85rem 0 0;
}

.result-value {
    align-items: baseline;
    background: #f8fafc;
    border-radius: .6rem;
    display: flex;
    gap: .6rem;
    margin-top: .9rem;
    padding: 1rem;
}

.result-unit-selector {
    align-items: stretch;
    background: #f8fafc;
    border: 1px solid #eaecf0;
    border-radius: .6rem;
    color: #475467;
    display: flex;
    flex-direction: column;
    font-size: .72rem;
    font-weight: 700;
    gap: .35rem;
    letter-spacing: .06em;
    margin-top: .85rem;
    padding: .65rem .72rem .72rem;
    text-transform: uppercase;
}

.result-unit-selector select {
    appearance: none;
    background: #fff;
    border: 1px solid #d0d5dd;
    border-radius: .45rem;
    color: var(--primary);
    cursor: pointer;
    font-size: .92rem;
    font-weight: 700;
    letter-spacing: normal;
    padding: .62rem 2.4rem .62rem .72rem;
    text-transform: none;
    width: 100%;
    background-image:
        linear-gradient(45deg, transparent 50%, var(--primary) 50%),
        linear-gradient(135deg, var(--primary) 50%, transparent 50%);
    background-position:
        calc(100% - 1rem) 50%,
        calc(100% - .7rem) 50%;
    background-repeat: no-repeat;
    background-size: .32rem .32rem, .32rem .32rem;
}

.result-unit-selector select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 .15rem rgba(0, 123, 255, .16);
    outline: none;
}

.result-value strong {
    color: #1d2939;
    font-size: 2rem;
    font-weight: 700;
}

.result-value.time-result-value strong {
    font-size: 1.35rem;
    line-height: 1.4;
}

.result-value span {
    color: var(--primary);
    font-size: 1rem;
    font-weight: 700;
}

.result-formula {
    color: #475467;
    font-size: .83rem;
    font-weight: 600;
    margin: .85rem 0 .35rem;
}

.result-summary {
    color: #344054;
    font-size: .9rem;
    font-weight: 600;
    margin: 0 0 .35rem;
}

.result-description {
    color: #667085;
    font-size: .83rem;
    margin: 0;
}

.drawing-placeholder {
    background: #f0f7ff;
    border: 1px dashed rgba(0, 123, 255, .38);
    border-radius: .6rem;
    color: #475467;
    display: flex;
    flex-direction: column;
    gap: .45rem;
    margin: .9rem 0 .7rem;
    min-height: 7rem;
    padding: 1rem;
}

.drawing-placeholder span {
    color: var(--primary);
    font-size: .73rem;
    font-weight: 700;
    text-transform: uppercase;
}

.drawing-placeholder strong {
    align-items: center;
    display: flex;
    flex: 1;
    font-weight: 600;
}

.calculation-not-found {
    background: #fff;
    border: 1px solid #eaecf0;
    border-radius: .75rem;
    max-width: 36rem;
    padding: 1.4rem;
}

.calculation-not-found p {
    color: #667085;
    margin-bottom: 1rem;
}

@media (max-width: 991px) {
    .category-grid {
        grid-template-columns: 1fr;
    }

    .calculation-layout {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 767px) {
    .formula-results {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 575px) {
    .calculation-home,
    .calculation-page {
        padding: 1rem .8rem 1.4rem;
    }

    .formula-card {
        padding: 1.1rem .9rem;
    }

    .formula-card-parameters {
        padding-left: 0;
    }

    .parameter-group-fields {
        grid-template-columns: 1fr;
    }
}