:root {
    --calculator-accent: #2e7d32;
    --calculator-accent-strong: #216b31;
    --calculator-muted: #667085;
}

.calculator-header {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    grid-template-rows: auto auto;
    align-items: flex-end;
    column-gap: 24px;
    margin-bottom: 18px;
    font-family: Inter, system-ui, "Segoe UI", Arial, sans-serif;
}

.calculator-brand {
    display: contents;
}

.calculator-header .title-banner {
    display: inline-block;
    margin: 0;
    padding: 8px 12px;
    border-radius: 8px;
    background: var(--calculator-accent);
    color: #fff;
    font-family: inherit;
    font-size: 18px;
    font-weight: 700;
    line-height: 1.3;
    text-align: left;
    align-self: end;
    justify-self: start;
    grid-column: 1;
    grid-row: 1;
}

.calculator-header .subtitle {
    margin: 8px 0 0;
    color: var(--calculator-muted);
    font-family: inherit;
    font-size: 14px;
    font-weight: 400;
    line-height: 1.45;
    grid-column: 1 / -1;
    grid-row: 2;
}

.calculator-header-actions {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    justify-content: flex-end;
    gap: 8px;
    align-self: end;
    grid-column: 2;
    grid-row: 1;
}

.calculator-header-controls {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 12px;
    flex-wrap: wrap;
}

.calculator-header .lang-switcher {
    position: static;
    display: flex;
    gap: 6px;
    z-index: auto;
}

.calculator-header .lang-btn {
    min-width: 48px;
    margin: 0;
    padding: 6px 14px;
    border: 2px solid var(--calculator-accent);
    border-radius: 6px;
    background: #fff;
    color: var(--calculator-accent);
    font-family: inherit;
    font-size: 13px;
    font-weight: 650;
    line-height: 1.35;
    cursor: pointer;
    box-shadow: none;
    transform: none;
}

.calculator-header .lang-btn:hover:not(.active) {
    background: #edf7ef;
    color: var(--calculator-accent-strong);
}

.calculator-header .lang-btn.active,
.calculator-header .lang-btn.active:hover {
    border-color: var(--calculator-accent);
    background: var(--calculator-accent);
    color: #fff;
}

.calculator-header .back-link {
    color: var(--calculator-accent);
    font-family: inherit;
    font-size: 13px;
    font-weight: 650;
    line-height: 1.35;
    text-decoration: none;
    white-space: nowrap;
}

.calculator-header .back-link:hover {
    text-decoration: underline;
}

@media (max-width: 560px) {
    .calculator-header {
        display: flex;
        align-items: stretch;
        flex-direction: column;
        gap: 14px;
    }

    .calculator-brand {
        display: block;
    }

    .calculator-header .subtitle {
        margin-top: 8px;
    }

    .calculator-header-actions {
        align-items: flex-start;
        justify-content: flex-start;
    }

    .calculator-header-controls {
        align-items: flex-start;
        justify-content: flex-start;
    }
}