/* ── Formula builder — premium math workbench ── */

.formula-page {
    display: grid;
    gap: var(--tp-space-4);
    --ff-accent-ink: var(--tp-color-brand-900);
    --ff-accent-soft: var(--tp-color-info-bg);
    --ff-accent-soft-2: var(--tp-color-brand-050);
    --ff-accent-border: var(--tp-color-brand-300);
    --ff-border: var(--tp-color-border-soft);
    --ff-mono: "JetBrains Mono", "SFMono-Regular", Menlo, Consolas, monospace;
    --ff-editor-bg: var(--tp-color-brand-900);
    --ff-editor-color: var(--tp-color-brand-100);
}

.formula-page h1,
.formula-page h2,
.formula-page h3 {
    font-family: "Space Grotesk", "Segoe UI", sans-serif;
    font-weight: 600;
    letter-spacing: -0.01em;
}
.formula-page h1 { font-weight: 700; }

.formula-page > form {
    display: contents;
}

/* ── Hero ── */

.formula-hero {
    position: relative;
    overflow: hidden;
    border: 1px solid var(--tp-color-border-soft);
    border-radius: var(--tp-ui-radius-hero);
    background: var(--tp-color-surface);
    padding: 22px 22px 18px;
}

.formula-hero::before {
    content: "";
    position: absolute;
    inset: 0 0 auto 0;
    height: 4px;
    background: linear-gradient(90deg, var(--tp-color-brand-800) 0%, var(--tp-color-sage-700) 55%, var(--tp-color-brand-500) 100%);
}

.formula-hero > * {
    position: relative;
    z-index: 1;
}

.formula-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin: 0 0 8px;
    color: var(--tp-color-text-muted);
    font-family: var(--ff-mono);
    font-size: var(--tp-font-label);
    font-weight: 500;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.formula-hero h1 {
    margin: 0;
    font-size: var(--tp-heading-lg);
    line-height: 1.05;
    color: var(--ff-accent-ink);
}

.formula-subtitle {
    margin: 10px 0 0;
    max-width: 900px;
    color: var(--tp-color-text-secondary);
    font-size: 1.03rem;
    line-height: 1.52;
}

.formula-chip-group {
    margin-top: 16px;
    gap: 8px;
    flex-wrap: wrap;
}

.formula-chip-group code {
    font-family: var(--ff-mono);
    font-size: 0.82em;
    color: var(--ff-accent-ink);
    background: none;
    padding: 0;
}

.formula-chip-id {
    font-family: var(--ff-mono);
    font-weight: 600;
    color: var(--ff-accent-ink);
}

/* ── Alert ── */

.formula-alert {
    border: 1px solid var(--tp-color-danger-border);
    border-radius: var(--tp-ui-radius-panel);
    background: var(--tp-color-danger-bg);
    padding: 14px 16px;
}

/* ── Workbench layout ── */

.formula-workbench {
    display: grid;
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 1fr);
    gap: 18px;
    align-items: start;
}

.formula-editor-col {
    display: grid;
    gap: 14px;
}

/* ── Cards ── */

.formula-card {
    border: 1px solid var(--tp-color-border-soft);
    border-radius: var(--tp-ui-radius-panel);
    background: var(--tp-color-surface);
    padding: 16px;
    display: grid;
    gap: 14px;
    align-content: start;
}

.formula-card--name {
    gap: 0;
}

.formula-card-head {
    align-items: flex-start;
    margin-bottom: 0;
}

.formula-card h2 {
    margin: 0;
    color: var(--ff-accent-ink);
    font-size: var(--tp-heading-sm);
    line-height: 1.15;
}

.formula-card-note {
    margin: 5px 0 0;
    color: var(--tp-color-text-muted);
    font-size: 0.92rem;
    line-height: 1.45;
}

/* ── Expression textarea (dark editor) ── */

.formula-expr-field {
    display: grid;
    gap: 8px;
}

.formula-expression-input {
    font-family: var(--ff-mono) !important;
    font-size: 0.92rem !important;
    line-height: 1.65 !important;
    resize: vertical;
    min-height: 120px;
    background: var(--ff-editor-bg) !important;
    color: var(--ff-editor-color) !important;
    border: 1px solid var(--tp-color-brand-700) !important;
    border-radius: 12px !important;
    caret-color: var(--tp-color-brand-300);
    padding: 14px 16px !important;
    transition: border-color 0.18s, box-shadow 0.18s;
}

.formula-expression-input::placeholder {
    color: color-mix(in srgb, var(--tp-color-brand-400) 55%, transparent) !important;
}

.formula-expression-input:focus {
    border-color: var(--tp-color-brand-400) !important;
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--tp-color-brand-400) 22%, transparent) !important;
    outline: none !important;
}

/* ── Validation badge ── */

.formula-validation-row {
    min-height: 22px;
    display: flex;
    align-items: center;
}

.formula-valid-badge {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 0.84rem;
    font-weight: 600;
    border-radius: 8px;
    padding: 3px 10px;
}

.formula-valid-badge--empty {
    color: var(--tp-color-text-muted);
}

.formula-valid-badge--ok {
    color: var(--tp-color-success-ink);
    background: var(--tp-color-success-bg);
}

.formula-valid-badge--err {
    color: var(--tp-color-danger-ink);
    background: var(--tp-color-danger-bg);
}

/* ── KaTeX preview ── */

.formula-katex-wrap {
    display: grid;
    gap: 6px;
}

.formula-katex-label {
    margin: 0;
    color: var(--tp-color-text-muted);
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.07em;
    text-transform: uppercase;
}

.formula-katex-block {
    border: 1px solid var(--tp-color-border-soft);
    border-radius: 12px;
    background: var(--tp-color-surface-soft);
    padding: 14px 16px;
    min-height: 58px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow-x: auto;
    color: var(--tp-color-text-primary);
    font-size: 1.08rem;
}

.formula-katex-placeholder {
    color: var(--tp-color-text-muted);
    font-size: 0.9rem;
    font-style: italic;
}

/* ── Palette (functions + operators) ── */

.formula-palette {
    display: grid;
    gap: 6px;
}

.formula-palette-label {
    margin: 0;
    color: var(--tp-color-text-muted);
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.07em;
    text-transform: uppercase;
}

.formula-palette-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.formula-fn-chip,
.formula-op-chip,
.formula-example-chip {
    display: inline-flex;
    align-items: center;
    border: 1px solid var(--tp-color-border-soft);
    border-radius: 8px;
    background: var(--tp-color-surface-soft);
    color: var(--ff-accent-ink);
    font-family: var(--ff-mono);
    font-size: 0.82rem;
    font-weight: 600;
    padding: 4px 10px;
    cursor: pointer;
    transition: background 0.14s, border-color 0.14s;
    line-height: 1.4;
}

.formula-fn-chip:hover,
.formula-op-chip:hover,
.formula-example-chip:hover {
    background: var(--tp-color-surface-muted);
    border-color: var(--tp-color-border);
}

.formula-op-chip {
    font-size: 1.05rem;
    padding: 3px 12px;
    min-width: 38px;
    justify-content: center;
}

.formula-example-chip {
    flex-direction: column;
    align-items: flex-start;
    gap: 3px;
    max-width: 100%;
    padding: 8px 10px;
    font-family: inherit;
}

.formula-example-chip span {
    color: var(--ff-accent-ink);
    font-size: 0.82rem;
    font-weight: 600;
}

.formula-example-chip code {
    max-width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--tp-color-text-secondary);
    font-family: var(--ff-mono);
    font-size: 0.76rem;
    white-space: nowrap;
}

/* ── Variables column ── */

.formula-vars-col {
    position: sticky;
    top: 16px;
}

.formula-card--vars {
    max-height: calc(100vh - 180px);
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.formula-var-search-wrap {
    flex-shrink: 0;
}

.formula-var-search {
    min-height: 38px;
}

.formula-var-groups {
    overflow-y: auto;
    flex: 1;
    display: grid;
    gap: 14px;
    padding-right: 2px;
    scrollbar-width: thin;
    scrollbar-color: var(--tp-color-border-soft) transparent;
}

.formula-var-group {
    display: grid;
    gap: 6px;
}

.formula-var-group-label {
    margin: 0;
    color: var(--tp-color-text-muted);
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    padding-bottom: 2px;
    border-bottom: 1px solid var(--tp-color-border-soft);
}

.formula-var-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
}

.formula-var-chip {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    border: 1px solid var(--tp-color-border-soft);
    border-radius: 7px;
    background: var(--tp-color-surface-soft);
    color: var(--tp-color-text-secondary);
    font-family: var(--ff-mono);
    font-size: var(--tp-font-label);
    font-weight: 500;
    padding: 3px 8px;
    cursor: pointer;
    transition: background 0.12s, border-color 0.12s, color 0.12s;
    line-height: 1.4;
    text-align: left;
    max-width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.formula-var-name {
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
}

.formula-var-kind {
    flex: 0 0 auto;
    border-radius: 999px;
    background: var(--tp-color-surface-muted);
    color: var(--tp-color-text-muted);
    font-family: var(--tp-font-body);
    font-size: 0.64rem;
    font-weight: 500;
    letter-spacing: 0.04em;
    line-height: 1;
    padding: 3px 6px;
    text-transform: uppercase;
}

.formula-var-chip--numeric {
    border-color: var(--tp-color-success-border);
    background: color-mix(in srgb, var(--tp-color-success-bg) 58%, var(--tp-color-surface));
}

.formula-var-chip--numeric .formula-var-kind {
    background: var(--tp-color-success-bg);
    color: var(--tp-color-success-ink);
}

.formula-var-chip:hover {
    background: var(--tp-color-surface-muted);
    border-color: var(--tp-color-border);
    color: var(--ff-accent-ink);
}

/* ── Field error ── */

.formula-field-error {
    margin: 2px 0 0;
    color: var(--tp-color-danger-ink);
    font-size: var(--tp-font-size-sm);
    font-weight: 600;
}

/* ── Footer ── */

.formula-footer {
    display: flex;
    align-items: flex-end;
    gap: 24px;
    justify-content: space-between;
    border: 1px solid var(--tp-color-border-soft);
    border-radius: var(--tp-ui-radius-panel);
    background: var(--tp-color-surface-soft);
    padding: 18px 22px;
}

.formula-footer-copy {
    min-width: 0;
    max-width: 720px;
    padding-bottom: 2px;
}

.formula-footer-title {
    margin: 0;
    color: var(--ff-accent-ink);
    font-size: 0.96rem;
    font-weight: 600;
}

.formula-footer-note {
    margin: 6px 0 0;
    color: var(--tp-color-text-secondary);
    font-size: 0.9rem;
    line-height: 1.5;
}

.formula-footer-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
    flex-shrink: 0;
    justify-content: flex-end;
}

.formula-footer-actions form {
    margin: 0;
}

/* ── Animations ── */

.formula-hero,
.formula-workbench,
.formula-footer {
    animation: formula-enter 0.36s ease both;
}

.formula-workbench { animation-delay: 0.04s; }
.formula-footer    { animation-delay: 0.08s; }

@keyframes formula-enter {
    from { opacity: 0; transform: translateY(6px); }
    to   { opacity: 1; transform: translateY(0); }
}

/* ── Responsive ── */

@media (max-width: 980px) {
    .formula-workbench {
        grid-template-columns: minmax(0, 1fr);
    }

    .formula-vars-col {
        position: static;
    }

    .formula-card--vars {
        max-height: 420px;
    }
}

@media (max-width: 768px) {
    .formula-hero {
        padding: 18px 16px 16px;
    }

    .formula-card {
        padding: 14px;
    }

    .formula-footer {
        flex-direction: column;
        align-items: stretch;
        gap: 16px;
        padding: 16px;
    }

    .formula-footer-actions {
        flex-direction: column;
        align-items: stretch;
    }

    .formula-footer-actions .btn {
        width: 100%;
    }
}

.tp-dark .formula-page {
    --ff-editor-bg: var(--tp-color-brand-050);
    --ff-editor-color: var(--tp-color-brand-900);
}