/* =========================================================
   DIMENSIONAL ANALYSIS PRACTICE PAGE
   ========================================================= */

:root
{
    --da-navy: #102a43;
    --da-navy-dark: #081c2f;
    --da-blue: #1f6f8b;
    --da-teal: #159a9c;
    --da-teal-dark: #117b7d;
    --da-green: #198754;
    --da-green-dark: #157347;
    --da-red: #c0392b;
    --da-orange: #d97706;
    --da-purple: #6f42c1;

    --da-light: #f5f8fb;
    --da-lighter: #fbfcfe;

    --da-border: #dbe5ee;

    --da-text: #243b53;
    --da-muted: #627d98;

    --da-white: #ffffff;

    --da-shadow:
        0 18px 45px rgba(16, 42, 67, 0.12);

    --da-shadow-small:
        0 8px 24px rgba(16, 42, 67, 0.09);
}


/* =========================================================
   GENERAL
   ========================================================= */

.da-practice-page
{
    background:
        var(--da-white);

    color:
        var(--da-text);

    font-family:
        "Inter",
        sans-serif;
}


.da-practice-page *,
.da-practice-page *::before,
.da-practice-page *::after
{
    box-sizing:
        border-box;
}


.da-practice-page button,
.da-practice-page input,
.da-practice-page select
{
    font-family:
        inherit;
}


.da-practice-page button
{
    cursor:
        pointer;
}


/* =========================================================
   PRACTICE SECTION
   ========================================================= */

.da-section
{
    position:
        relative;

    padding:
        5rem 1.5rem;

    background:
        radial-gradient(
            circle at top left,
            rgba(21, 154, 156, 0.08),
            transparent 32rem
        ),
        linear-gradient(
            180deg,
            #ffffff 0%,
            #f5f8fb 100%
        );
}


.da-app
{
    width:
        min(100%, 1180px);

    margin:
        0 auto;
}


/* =========================================================
   TOOLBAR
   ========================================================= */

.da-toolbar
{
    display:
        flex;

    align-items:
        flex-end;

    justify-content:
        space-between;

    gap:
        2rem;

    margin-bottom:
        2rem;
}


.da-toolbar-heading
{
    max-width:
        760px;
}


.da-toolbar-heading h2
{
    margin:
        0 0 0.75rem;

    color:
        var(--da-navy);

    font-size:
        clamp(1.65rem, 3.2vw, 2.2rem);

    font-weight:
        800;

    line-height:
        1.15;
}


.da-toolbar-heading p:last-child
{
    margin:
        0;

    color:
        var(--da-muted);

    font-size:
        1rem;

    line-height:
        1.7;
}


.da-eyebrow
{
    margin:
        0 0 0.5rem;

    color:
        var(--da-teal-dark);

    font-size:
        0.78rem;

    font-weight:
        800;

    letter-spacing:
        0.12em;

    text-transform:
        uppercase;
}


.da-controls
{
    flex:
        0 0 auto;
}


.da-control-group
{
    min-width:
        190px;
}


.da-control-group label
{
    display:
        block;

    margin-bottom:
        0.45rem;

    color:
        var(--da-navy);

    font-size:
        0.85rem;

    font-weight:
        700;
}


.da-select
{
    width:
        100%;

    min-height:
        48px;

    padding:
        0.7rem 2.5rem 0.7rem 0.95rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.75rem;

    background:
        var(--da-white);

    color:
        var(--da-navy);

    font-size:
        0.95rem;

    font-weight:
        700;

    outline:
        none;

    box-shadow:
        var(--da-shadow-small);

    transition:
        border-color 0.2s ease,
        box-shadow 0.2s ease;
}


.da-select:hover
{
    border-color:
        rgba(21, 154, 156, 0.6);
}


.da-select:focus
{
    border-color:
        var(--da-teal);

    box-shadow:
        0 0 0 4px rgba(21, 154, 156, 0.14),
        var(--da-shadow-small);
}


/* =========================================================
   MODE SELECTOR
   ========================================================= */

.da-mode-selector
{
    margin-bottom:
        1.7rem;

    padding:
        1.25rem;

    border:
        1px solid var(--da-border);

    border-radius:
        1rem;

    background:
        var(--da-white);

    box-shadow:
        var(--da-shadow-small);
}


.da-mode-heading
{
    display:
        flex;

    align-items:
        baseline;

    justify-content:
        space-between;

    gap:
        1rem;

    margin-bottom:
        0.9rem;
}


.da-mode-label
{
    color:
        var(--da-navy);

    font-size:
        0.9rem;

    font-weight:
        800;
}


.da-mode-help
{
    color:
        var(--da-muted);

    font-size:
        0.8rem;
}


.da-mode-tabs
{
    display:
        grid;

    grid-template-columns:
        repeat(7, minmax(0, 1fr));

    gap:
        0.7rem;
}


.da-mode-button
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        center;

    gap:
        0.5rem;

    min-height:
        68px;

    padding:
        0.8rem 0.6rem;

    border:
        2px solid var(--da-border);

    border-radius:
        0.85rem;

    background:
        var(--da-lighter);

    color:
        var(--da-navy);

    font-size:
        0.72rem;

    font-weight:
        800;

    line-height:
        1.3;

    text-align:
        center;

    transition:
        transform 0.2s ease,
        border-color 0.2s ease,
        background-color 0.2s ease,
        color 0.2s ease,
        box-shadow 0.2s ease;
}


.da-mode-button svg
{
    flex:
        0 0 auto;

    width:
        18px;

    height:
        18px;
}


.da-mode-button:hover
{
    transform:
        translateY(-1px);

    border-color:
        rgba(21, 154, 156, 0.5);

    background:
        rgba(21, 154, 156, 0.055);

    color:
        var(--da-teal-dark);
}


.da-mode-button.is-active
{
    border-color:
        var(--da-teal);

    background:
        linear-gradient(
            135deg,
            rgba(21, 154, 156, 0.13),
            rgba(31, 111, 139, 0.07)
        );

    color:
        var(--da-teal-dark);

    box-shadow:
        0 6px 18px rgba(21, 154, 156, 0.14);
}


/* =========================================================
   ROUND PROGRESS
   ========================================================= */

.da-progress-area
{
    margin-bottom:
        1.25rem;
}


.da-progress-text
{
    display:
        flex;

    justify-content:
        space-between;

    gap:
        1rem;

    margin-bottom:
        0.6rem;

    color:
        var(--da-navy);

    font-size:
        0.88rem;

    font-weight:
        700;
}


.da-progress-track
{
    width:
        100%;

    height:
        12px;

    overflow:
        hidden;

    border-radius:
        999px;

    background:
        #dfe9f1;
}


.da-progress-bar
{
    width:
        10%;

    height:
        100%;

    border-radius:
        inherit;

    background:
        linear-gradient(
            90deg,
            var(--da-teal),
            var(--da-blue)
        );

    transition:
        width 0.35s ease;
}


/* =========================================================
   MAIN CARD
   ========================================================= */

.da-card
{
    padding:
        clamp(1.4rem, 4vw, 2.5rem);

    border:
        1px solid rgba(219, 229, 238, 0.9);

    border-radius:
        1.35rem;

    background:
        var(--da-white);

    box-shadow:
        var(--da-shadow);
}


.da-card-top
{
    display:
        flex;

    align-items:
        flex-start;

    justify-content:
        space-between;

    gap:
        1rem;

    margin-bottom:
        1.5rem;
}


.da-card-label
{
    margin:
        0 0 0.3rem;

    color:
        var(--da-navy);

    font-size:
        0.95rem;

    font-weight:
        800;
}


.da-step-instruction
{
    margin:
        0;

    color:
        var(--da-muted);

    font-size:
        0.92rem;

    line-height:
        1.5;
}


.da-card-badges
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        flex-end;

    flex-wrap:
        wrap;

    gap:
        0.5rem;
}


.da-mode-badge,
.da-difficulty-badge
{
    display:
        inline-flex;

    align-items:
        center;

    justify-content:
        center;

    min-height:
        34px;

    padding:
        0.45rem 0.8rem;

    border-radius:
        999px;

    font-size:
        0.75rem;

    font-weight:
        800;

    letter-spacing:
        0.03em;

    white-space:
        nowrap;
}


.da-mode-badge
{
    background:
        rgba(31, 111, 139, 0.11);

    color:
        var(--da-blue);
}


.da-difficulty-badge
{
    background:
        rgba(21, 154, 156, 0.11);

    color:
        var(--da-teal-dark);
}


/* =========================================================
   CURRENT PROBLEM
   ========================================================= */

.da-current-problem-area
{
    margin-bottom:
        1.25rem;

    padding:
        1.4rem;

    border:
        1px solid var(--da-border);

    border-radius:
        1rem;

    background:
        linear-gradient(
            135deg,
            rgba(21, 154, 156, 0.055),
            rgba(31, 111, 139, 0.03)
        );

    text-align:
        center;
}


.da-problem-label
{
    display:
        block;

    margin-bottom:
        0.65rem;

    color:
        var(--da-muted);

    font-size:
        0.76rem;

    font-weight:
        800;

    letter-spacing:
        0.08em;

    text-transform:
        uppercase;
}


.da-problem-expression
{
    margin-bottom:
        0.75rem;

    color:
        var(--da-navy-dark);

    font-size:
        clamp(1.75rem, 6vw, 2.8rem);

    font-weight:
        800;

    line-height:
        1.25;

    overflow-wrap:
        anywhere;
}


.da-problem-prompt
{
    margin:
        0;

    color:
        var(--da-navy);

    font-size:
        clamp(1rem, 2.5vw, 1.15rem);

    font-weight:
        750;

    line-height:
        1.5;
}


/* =========================================================
   UNIT GOAL PANEL
   ========================================================= */

.da-unit-goal-panel
{
    display:
        grid;

    grid-template-columns:
        minmax(0, 1fr)
        auto
        minmax(0, 1fr)
        auto
        minmax(0, 1fr);

    align-items:
        stretch;

    gap:
        0.75rem;

    margin-bottom:
        1.5rem;

    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        1rem;

    background:
        var(--da-lighter);
}


.da-unit-goal-item
{
    display:
        flex;

    flex-direction:
        column;

    align-items:
        center;

    justify-content:
        center;

    gap:
        0.25rem;

    min-height:
        74px;

    padding:
        0.8rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.8rem;

    background:
        var(--da-white);

    text-align:
        center;
}


.da-unit-goal-item span
{
    color:
        var(--da-muted);

    font-size:
        0.68rem;

    font-weight:
        800;

    letter-spacing:
        0.07em;

    text-transform:
        uppercase;
}


.da-unit-goal-item strong
{
    color:
        var(--da-navy);

    font-size:
        1rem;

    font-weight:
        800;
}


.da-current-unit-item
{
    border-color:
        rgba(21, 154, 156, 0.3);

    background:
        rgba(21, 154, 156, 0.055);
}


.da-current-unit-item strong
{
    color:
        var(--da-teal-dark);
}


.da-unit-goal-arrow
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        center;

    color:
        var(--da-muted);

    font-size:
        1rem;
}


/* =========================================================
   STEP PROGRESS
   ========================================================= */

.da-step-progress
{
    display:
        grid;

    grid-template-columns:
        auto
        minmax(20px, 1fr)
        auto
        minmax(20px, 1fr)
        auto;

    align-items:
        center;

    gap:
        0.55rem;

    margin:
        1.8rem 0;
}


.da-step-marker
{
    display:
        flex;

    flex-direction:
        column;

    align-items:
        center;

    gap:
        0.35rem;

    min-width:
        84px;

    text-align:
        center;
}


.da-step-marker span
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        center;

    width:
        38px;

    height:
        38px;

    border:
        2px solid var(--da-border);

    border-radius:
        50%;

    background:
        var(--da-white);

    color:
        var(--da-muted);

    font-size:
        0.84rem;

    font-weight:
        800;

    transition:
        border-color 0.25s ease,
        background-color 0.25s ease,
        color 0.25s ease,
        transform 0.25s ease;
}


.da-step-marker small
{
    color:
        var(--da-muted);

    font-size:
        0.68rem;

    font-weight:
        700;

    line-height:
        1.2;
}


.da-step-marker.is-active span
{
    border-color:
        var(--da-teal);

    background:
        var(--da-teal);

    color:
        var(--da-white);

    transform:
        scale(1.05);
}


.da-step-marker.is-active small
{
    color:
        var(--da-teal-dark);

    font-weight:
        800;
}


.da-step-marker.is-complete span
{
    border-color:
        var(--da-green);

    background:
        var(--da-green);

    color:
        var(--da-white);
}


.da-step-marker.is-complete small
{
    color:
        var(--da-green);
}


.da-step-connector
{
    height:
        3px;

    border-radius:
        999px;

    background:
        var(--da-border);

    transition:
        background-color 0.25s ease;
}


.da-step-connector.is-complete
{
    background:
        var(--da-green);
}


/* =========================================================
   WORK AREA
   ========================================================= */

.da-work-area
{
    margin-top:
        1rem;

    padding:
        clamp(1.25rem, 3vw, 1.8rem);

    border:
        2px solid rgba(21, 154, 156, 0.2);

    border-radius:
        1rem;

    background:
        linear-gradient(
            135deg,
            rgba(21, 154, 156, 0.065),
            rgba(31, 111, 139, 0.035)
        );
}


.da-work-step-number
{
    margin:
        0 0 0.35rem;

    color:
        var(--da-teal-dark);

    font-size:
        0.76rem;

    font-weight:
        800;

    letter-spacing:
        0.1em;

    text-transform:
        uppercase;
}


.da-work-area h3
{
    margin:
        0 0 0.55rem;

    color:
        var(--da-navy);

    font-size:
        clamp(1.2rem, 3vw, 1.55rem);

    font-weight:
        800;

    line-height:
        1.3;
}


.da-work-description
{
    margin:
        0 0 1.3rem;

    color:
        var(--da-muted);

    font-size:
        0.9rem;

    line-height:
        1.65;
}


/* =========================================================
   PROBLEM REMINDER
   ========================================================= */

.da-problem-reminder
{
    margin:
        1.2rem 0 1.4rem;

    padding:
        1.05rem 1.2rem;

    border:
        1px solid rgba(21, 154, 156, 0.22);

    border-radius:
        0.9rem;

    background:
        var(--da-white);

    text-align:
        center;

    box-shadow:
        var(--da-shadow-small);
}


.da-reminder-label
{
    display:
        block;

    margin-bottom:
        0.35rem;

    color:
        var(--da-muted);

    font-size:
        0.68rem;

    font-weight:
        800;

    letter-spacing:
        0.08em;

    text-transform:
        uppercase;
}


.da-reminder-expression
{
    color:
        var(--da-teal-dark);

    font-size:
        clamp(1.25rem, 4vw, 1.8rem);

    font-weight:
        800;

    line-height:
        1.4;
}


/* =========================================================
   WORKBENCH
   ========================================================= */

.da-workbench
{
    margin-top:
        1.4rem;

    padding:
        1.1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        1rem;

    background:
        var(--da-white);

    box-shadow:
        var(--da-shadow-small);
}


.da-workbench-heading
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        space-between;

    gap:
        1rem;

    margin-bottom:
        1rem;
}


.da-workbench-heading > div
{
    display:
        flex;

    flex-direction:
        column;

    gap:
        0.2rem;
}


.da-workbench-label
{
    color:
        var(--da-muted);

    font-size:
        0.7rem;

    font-weight:
        800;

    letter-spacing:
        0.08em;

    text-transform:
        uppercase;
}


.da-workbench-heading strong
{
    color:
        var(--da-navy);

    font-size:
        0.9rem;

    font-weight:
        800;

    line-height:
        1.45;
}


.da-chain-status-badge
{
    flex:
        0 0 auto;

    padding:
        0.45rem 0.75rem;

    border:
        1px solid rgba(21, 154, 156, 0.25);

    border-radius:
        999px;

    background:
        rgba(21, 154, 156, 0.08);

    color:
        var(--da-teal-dark);

    font-size:
        0.72rem;

    font-weight:
        800;
}


.da-chain-status-badge.is-correct
{
    border-color:
        rgba(25, 135, 84, 0.3);

    background:
        rgba(25, 135, 84, 0.08);

    color:
        var(--da-green-dark);
}


.da-chain-status-badge.is-incorrect
{
    border-color:
        rgba(192, 57, 43, 0.3);

    background:
        rgba(192, 57, 43, 0.07);

    color:
        #8f2e24;
}


/* =========================================================
   CHAIN VIEWPORT
   ========================================================= */

.da-chain-viewport
{
    width:
        100%;

    overflow-x:
        auto;

    overflow-y:
        hidden;

    padding:
        0.25rem 0 0.7rem;

    scrollbar-width:
        thin;
}


.da-conversion-chain
{
    display:
        flex;

    align-items:
        center;

    gap:
        0.75rem;

    min-width:
        max-content;

    min-height:
        130px;

    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.9rem;

    background:
        linear-gradient(
            180deg,
            #ffffff,
            #fbfcfe
        );
}


.da-chain-quantity,
.da-selected-factor
{
    display:
        grid;

    grid-template-rows:
        auto 3px auto;

    align-items:
        center;

    min-width:
        110px;

    padding:
        0.75rem 0.9rem;

    border:
        2px solid var(--da-border);

    border-radius:
        0.85rem;

    background:
        var(--da-white);

    color:
        var(--da-navy);

    text-align:
        center;

    box-shadow:
        0 4px 14px rgba(16, 42, 67, 0.06);
}


.da-chain-quantity
{
    border-color:
        rgba(31, 111, 139, 0.35);

    background:
        rgba(31, 111, 139, 0.045);
}


.da-selected-factor
{
    position:
        relative;
}


.da-selected-factor::before
{
    content:
        "×";

    position:
        absolute;

    top:
        50%;

    left:
        -0.7rem;

    transform:
        translate(-50%, -50%);

    color:
        var(--da-muted);

    font-size:
        1.2rem;

    font-weight:
        800;
}


.da-fraction-numerator,
.da-fraction-denominator
{
    padding:
        0.25rem 0.15rem;

    font-size:
        0.95rem;

    font-weight:
        800;

    line-height:
        1.35;
}


.da-fraction-bar
{
    width:
        100%;

    height:
        3px;

    border-radius:
        999px;

    background:
        var(--da-navy);
}


.da-selected-factor.is-correct
{
    border-color:
        rgba(25, 135, 84, 0.45);

    background:
        rgba(25, 135, 84, 0.045);
}


.da-selected-factor.is-incorrect
{
    border-color:
        rgba(192, 57, 43, 0.4);

    background:
        rgba(192, 57, 43, 0.04);
}


/* =========================================================
   UNIT CANCELLATION
   ========================================================= */

.da-unit-cancellation-panel
{
    margin-top:
        1rem;

    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.9rem;

    background:
        var(--da-lighter);
}


.da-unit-cancellation-label
{
    display:
        block;

    margin-bottom:
        0.55rem;

    color:
        var(--da-muted);

    font-size:
        0.68rem;

    font-weight:
        800;

    letter-spacing:
        0.08em;

    text-transform:
        uppercase;
}


.da-unit-cancellation-display
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        center;

    flex-wrap:
        wrap;

    gap:
        0.5rem;

    min-height:
        58px;

    padding:
        0.8rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.75rem;

    background:
        var(--da-white);

    color:
        var(--da-navy);

    font-size:
        1rem;

    font-weight:
        800;

    line-height:
        1.5;
}


.da-unit-cancellation-display .is-cancelled
{
    position:
        relative;

    color:
        var(--da-muted);
}


.da-unit-cancellation-display .is-cancelled::after
{
    content:
        "";

    position:
        absolute;

    top:
        50%;

    left:
        -4px;

    right:
        -4px;

    height:
        2px;

    background:
        var(--da-red);

    transform:
        rotate(-12deg);
}


.da-unit-cancellation-display .is-target-unit
{
    padding:
        0.25rem 0.45rem;

    border-radius:
        0.45rem;

    background:
        rgba(25, 135, 84, 0.08);

    color:
        var(--da-green-dark);
}


.da-unit-cancellation-explanation
{
    margin:
        0.7rem 0 0;

    color:
        var(--da-muted);

    font-size:
        0.82rem;

    line-height:
        1.55;

    text-align:
        center;
}


/* =========================================================
   FACTOR TRAY
   ========================================================= */

.da-factor-tray
{
    margin-top:
        1rem;

    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.9rem;

    background:
        var(--da-white);
}


.da-factor-tray-heading
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        space-between;

    gap:
        1rem;

    margin-bottom:
        0.9rem;
}


.da-factor-tray-heading > div
{
    display:
        flex;

    flex-direction:
        column;

    gap:
        0.2rem;
}


.da-factor-tray-heading span
{
    color:
        var(--da-muted);

    font-size:
        0.68rem;

    font-weight:
        800;

    letter-spacing:
        0.07em;

    text-transform:
        uppercase;
}


.da-factor-tray-heading strong
{
    color:
        var(--da-navy);

    font-size:
        0.88rem;

    font-weight:
        800;
}


.da-small-button
{
    display:
        inline-flex;

    align-items:
        center;

    justify-content:
        center;

    gap:
        0.4rem;

    min-height:
        38px;

    padding:
        0.5rem 0.75rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.65rem;

    background:
        var(--da-white);

    color:
        var(--da-navy);

    font-size:
        0.76rem;

    font-weight:
        800;
}


.da-small-button:hover:not(:disabled)
{
    border-color:
        rgba(21, 154, 156, 0.5);

    background:
        rgba(21, 154, 156, 0.05);

    color:
        var(--da-teal-dark);
}


.da-small-button:disabled
{
    cursor:
        not-allowed;

    opacity:
        0.45;
}


.da-factor-card-grid
{
    display:
        grid;

    grid-template-columns:
        repeat(3, minmax(0, 1fr));

    gap:
        0.8rem;
}


/* =========================================================
   FACTOR CARD
   ========================================================= */

.da-factor-card
{
    position:
        relative;

    display:
        flex;

    flex-direction:
        column;

    align-items:
        stretch;

    justify-content:
        center;

    min-height:
        110px;

    padding:
        0.8rem;

    border:
        2px solid var(--da-border);

    border-radius:
        0.85rem;

    background:
        var(--da-lighter);

    color:
        var(--da-navy);

    text-align:
        center;

    transition:
        transform 0.18s ease,
        border-color 0.18s ease,
        background-color 0.18s ease,
        box-shadow 0.18s ease;
}


.da-factor-card:hover
{
    transform:
        translateY(-2px);

    border-color:
        rgba(21, 154, 156, 0.55);

    background:
        rgba(21, 154, 156, 0.045);

    box-shadow:
        0 6px 18px rgba(16, 42, 67, 0.08);
}


.da-factor-card.is-selected
{
    border-color:
        var(--da-teal);

    background:
        rgba(21, 154, 156, 0.07);
}


.da-factor-card.is-correct
{
    border-color:
        var(--da-green);

    background:
        rgba(25, 135, 84, 0.06);
}


.da-factor-card.is-incorrect
{
    border-color:
        var(--da-red);

    background:
        rgba(192, 57, 43, 0.055);
}


.da-factor-card .da-factor-top,
.da-factor-card .da-factor-bottom
{
    padding:
        0.25rem;

    font-size:
        0.9rem;

    font-weight:
        800;
}


.da-factor-card .da-factor-line
{
    width:
        100%;

    height:
        3px;

    margin:
        0.25rem 0;

    border-radius:
        999px;

    background:
        var(--da-navy);
}


.da-factor-card .da-factor-note
{
    margin-top:
        0.45rem;

    color:
        var(--da-muted);

    font-size:
        0.66rem;

    font-weight:
        700;
}


/* =========================================================
   CHAIN ACTIONS
   ========================================================= */

.da-chain-actions
{
    display:
        flex;

    justify-content:
        center;

    margin-top:
        1rem;
}


.da-chain-check-button
{
    display:
        inline-flex;

    align-items:
        center;

    justify-content:
        center;

    gap:
        0.45rem;

    min-height:
        50px;

    padding:
        0.8rem 1.2rem;

    border:
        0;

    border-radius:
        0.8rem;

    background:
        linear-gradient(
            135deg,
            var(--da-teal),
            var(--da-blue)
        );

    color:
        var(--da-white);

    font-size:
        0.88rem;

    font-weight:
        800;

    box-shadow:
        0 8px 20px rgba(21, 154, 156, 0.2);
}


.da-chain-check-button:hover
{
    transform:
        translateY(-1px);
}


/* =========================================================
   SPECIAL PANELS
   ========================================================= */

.da-power-panel,
.da-rate-panel,
.da-science-panel
{
    margin-top:
        1rem;

    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.9rem;

    background:
        var(--da-white);
}


.da-power-panel[hidden],
.da-rate-panel[hidden],
.da-science-panel[hidden]
{
    display:
        none !important;
}


.da-power-panel
{
    border-left:
        4px solid var(--da-purple);

    background:
        rgba(111, 66, 193, 0.04);
}


.da-rate-panel
{
    border-left:
        4px solid var(--da-orange);

    background:
        rgba(217, 119, 6, 0.04);
}


.da-science-panel
{
    border-left:
        4px solid var(--da-blue);

    background:
        rgba(31, 111, 139, 0.04);
}


.da-panel-heading
{
    margin-bottom:
        0.8rem;
}


.da-panel-heading span
{
    display:
        block;

    margin-bottom:
        0.2rem;

    color:
        var(--da-muted);

    font-size:
        0.68rem;

    font-weight:
        800;

    letter-spacing:
        0.07em;

    text-transform:
        uppercase;
}


.da-panel-heading strong
{
    color:
        var(--da-navy);

    font-size:
        0.9rem;

    font-weight:
        800;
}


.da-power-display,
.da-rate-unit-display,
.da-science-relationship-display
{
    margin:
        0.6rem 0;

    padding:
        0.9rem;

    border-radius:
        0.75rem;

    background:
        #101827;

    color:
        var(--da-white);

    font-size:
        clamp(1rem, 3vw, 1.3rem);

    font-weight:
        800;

    text-align:
        center;
}


.da-panel-explanation
{
    margin:
        0;

    color:
        var(--da-text);

    font-size:
        0.84rem;

    line-height:
        1.6;
}


/* =========================================================
   CHOICE ANSWERS
   ========================================================= */

.da-choice-answer-area
{
    margin-top:
        1rem;

    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.9rem;

    background:
        var(--da-white);
}


.da-choice-answer-area[hidden]
{
    display:
        none !important;
}


.da-answer-heading
{
    margin-bottom:
        0.8rem;
}


.da-answer-heading span
{
    display:
        block;

    margin-bottom:
        0.2rem;

    color:
        var(--da-muted);

    font-size:
        0.68rem;

    font-weight:
        800;

    letter-spacing:
        0.07em;

    text-transform:
        uppercase;
}


.da-answer-heading strong
{
    color:
        var(--da-navy);

    font-size:
        0.9rem;

    font-weight:
        800;
}


.da-choice-grid
{
    display:
        grid;

    grid-template-columns:
        repeat(2, minmax(0, 1fr));

    gap:
        0.8rem;
}


.da-choice-button
{
    min-height:
        58px;

    padding:
        0.8rem 1rem;

    border:
        2px solid var(--da-border);

    border-radius:
        0.85rem;

    background:
        var(--da-white);

    color:
        var(--da-navy);

    font-size:
        0.9rem;

    font-weight:
        800;

    text-align:
        center;

    transition:
        transform 0.18s ease,
        border-color 0.18s ease,
        background-color 0.18s ease,
        color 0.18s ease;
}


.da-choice-button:hover
{
    transform:
        translateY(-1px);

    border-color:
        rgba(21, 154, 156, 0.55);

    background:
        rgba(21, 154, 156, 0.055);

    color:
        var(--da-teal-dark);
}


.da-choice-button.is-correct
{
    border-color:
        var(--da-green);

    background:
        rgba(25, 135, 84, 0.075);

    color:
        var(--da-green-dark);
}


.da-choice-button.is-incorrect
{
    border-color:
        var(--da-red);

    background:
        rgba(192, 57, 43, 0.065);

    color:
        #8f2e24;
}


/* =========================================================
   NUMERIC ANSWER
   ========================================================= */

.da-answer-form
{
    margin-top:
        1rem;

    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.9rem;

    background:
        var(--da-white);
}


.da-answer-form[hidden]
{
    display:
        none !important;
}


.da-input-label
{
    display:
        block;

    margin-bottom:
        0.6rem;

    color:
        var(--da-navy);

    font-size:
        0.88rem;

    font-weight:
        800;
}


.da-input-row
{
    display:
        grid;

    grid-template-columns:
        minmax(0, 1fr)
        auto
        auto;

    gap:
        0.8rem;

    align-items:
        stretch;
}


.da-step-input
{
    width:
        100%;

    min-height:
        56px;

    padding:
        0.85rem 1rem;

    border:
        2px solid var(--da-border);

    border-radius:
        0.85rem;

    background:
        var(--da-white);

    color:
        var(--da-navy-dark);

    font-size:
        1.05rem;

    font-weight:
        650;

    outline:
        none;

    transition:
        border-color 0.2s ease,
        box-shadow 0.2s ease,
        background-color 0.2s ease;
}


.da-step-input:focus
{
    border-color:
        var(--da-teal);

    box-shadow:
        0 0 0 4px rgba(21, 154, 156, 0.13);
}


.da-step-input.is-correct
{
    border-color:
        var(--da-green);

    background:
        rgba(25, 135, 84, 0.045);
}


.da-step-input.is-incorrect
{
    border-color:
        var(--da-red);

    background:
        rgba(192, 57, 43, 0.045);
}


.da-answer-unit
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        center;

    min-width:
        80px;

    padding:
        0.7rem 0.9rem;

    border:
        2px solid rgba(21, 154, 156, 0.18);

    border-radius:
        0.85rem;

    background:
        rgba(21, 154, 156, 0.055);

    color:
        var(--da-teal-dark);

    font-size:
        0.95rem;

    font-weight:
        800;
}


/* =========================================================
   PRIMARY BUTTONS
   ========================================================= */

.da-submit-button,
.da-next-button
{
    display:
        inline-flex;

    align-items:
        center;

    justify-content:
        center;

    gap:
        0.45rem;

    min-height:
        56px;

    padding:
        0.85rem 1.4rem;

    border:
        0;

    border-radius:
        0.85rem;

    color:
        var(--da-white);

    font-size:
        0.92rem;

    font-weight:
        800;

    white-space:
        nowrap;

    transition:
        transform 0.2s ease,
        box-shadow 0.2s ease,
        filter 0.2s ease;
}


.da-submit-button
{
    background:
        linear-gradient(
            135deg,
            var(--da-teal),
            var(--da-blue)
        );

    box-shadow:
        0 8px 20px rgba(21, 154, 156, 0.22);
}


.da-next-button
{
    background:
        linear-gradient(
            135deg,
            var(--da-green),
            var(--da-green-dark)
        );

    box-shadow:
        0 8px 20px rgba(25, 135, 84, 0.22);
}


.da-submit-button:hover,
.da-next-button:hover
{
    transform:
        translateY(-2px);

    filter:
        brightness(1.04);
}


/* =========================================================
   SOLUTION SUMMARY
   ========================================================= */

.da-solution-summary
{
    margin-top:
        1rem;

    padding:
        1rem;

    border:
        1px solid rgba(25, 135, 84, 0.26);

    border-radius:
        0.9rem;

    background:
        rgba(25, 135, 84, 0.055);
}


.da-solution-summary[hidden]
{
    display:
        none !important;
}


.da-solution-summary-label
{
    display:
        block;

    margin-bottom:
        0.45rem;

    color:
        var(--da-green-dark);

    font-size:
        0.68rem;

    font-weight:
        800;

    letter-spacing:
        0.08em;

    text-transform:
        uppercase;
}


.da-solution-chain-display
{
    color:
        var(--da-navy);

    font-size:
        1rem;

    font-weight:
        800;

    line-height:
        1.65;

    overflow-wrap:
        anywhere;
}


/* =========================================================
   FEEDBACK
   ========================================================= */

.da-feedback
{
    margin-top:
        1.35rem;

    padding:
        1rem 1.1rem;

    border:
        1px solid var(--da-border);

    border-left-width:
        4px;

    border-radius:
        0.8rem;

    font-size:
        0.9rem;

    font-weight:
        650;

    line-height:
        1.6;
}


.da-feedback-neutral
{
    border-left-color:
        var(--da-blue);

    background:
        rgba(31, 111, 139, 0.05);

    color:
        var(--da-text);
}


.da-feedback-correct
{
    border-color:
        rgba(25, 135, 84, 0.25);

    border-left-color:
        var(--da-green);

    background:
        rgba(25, 135, 84, 0.065);

    color:
        #12663f;
}


.da-feedback-incorrect
{
    border-color:
        rgba(192, 57, 43, 0.22);

    border-left-color:
        var(--da-red);

    background:
        rgba(192, 57, 43, 0.055);

    color:
        #8f2e24;
}


/* =========================================================
   ACTION ROW
   ========================================================= */

.da-action-row
{
    display:
        flex;

    flex-wrap:
        wrap;

    gap:
        0.7rem;

    margin-top:
        1.25rem;
}


.da-secondary-button
{
    display:
        inline-flex;

    align-items:
        center;

    justify-content:
        center;

    gap:
        0.45rem;

    min-height:
        42px;

    padding:
        0.6rem 0.9rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.7rem;

    background:
        var(--da-white);

    color:
        var(--da-navy);

    font-size:
        0.82rem;

    font-weight:
        750;

    transition:
        border-color 0.2s ease,
        background-color 0.2s ease,
        color 0.2s ease,
        transform 0.2s ease;
}


.da-secondary-button:hover
{
    transform:
        translateY(-1px);

    border-color:
        rgba(21, 154, 156, 0.5);

    background:
        rgba(21, 154, 156, 0.055);

    color:
        var(--da-teal-dark);
}


/* =========================================================
   HINT PANEL
   ========================================================= */

.da-help-panel
{
    display:
        grid;

    grid-template-columns:
        auto minmax(0, 1fr);

    gap:
        1rem;

    margin-top:
        1.25rem;

    padding:
        1.1rem;

    border:
        1px solid rgba(217, 119, 6, 0.24);

    border-radius:
        0.9rem;

    background:
        rgba(217, 119, 6, 0.055);
}


.da-help-panel[hidden]
{
    display:
        none !important;
}


.da-help-panel-icon
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        center;

    width:
        42px;

    height:
        42px;

    border-radius:
        50%;

    background:
        rgba(217, 119, 6, 0.12);

    color:
        var(--da-orange);
}


.da-help-panel strong
{
    display:
        block;

    margin-bottom:
        0.25rem;

    color:
        var(--da-navy);

    font-size:
        0.9rem;
}


.da-help-panel p
{
    margin:
        0;

    color:
        var(--da-text);

    font-size:
        0.86rem;

    line-height:
        1.6;
}


/* =========================================================
   REFERENCE PANEL
   ========================================================= */

.da-reference-panel
{
    margin-top:
        1.25rem;

    padding:
        1.25rem;

    border:
        1px solid var(--da-border);

    border-radius:
        1rem;

    background:
        var(--da-white);

    box-shadow:
        var(--da-shadow-small);
}


.da-reference-panel[hidden]
{
    display:
        none !important;
}


.da-reference-panel-heading
{
    display:
        flex;

    align-items:
        flex-start;

    justify-content:
        space-between;

    gap:
        1rem;

    margin-bottom:
        1rem;
}


.da-reference-panel-heading h3
{
    margin:
        0 0 0.35rem;

    color:
        var(--da-navy);

    font-size:
        1.25rem;

    font-weight:
        800;
}


.da-reference-panel-heading p:last-child
{
    margin:
        0;

    color:
        var(--da-muted);

    font-size:
        0.84rem;

    line-height:
        1.55;
}


.da-reference-eyebrow
{
    margin:
        0 0 0.25rem;

    color:
        var(--da-teal-dark);

    font-size:
        0.68rem;

    font-weight:
        800;

    letter-spacing:
        0.08em;

    text-transform:
        uppercase;
}


.da-close-button
{
    display:
        inline-flex;

    align-items:
        center;

    justify-content:
        center;

    width:
        38px;

    height:
        38px;

    padding:
        0;

    border:
        1px solid var(--da-border);

    border-radius:
        50%;

    background:
        var(--da-white);

    color:
        var(--da-muted);
}


.da-close-button:hover
{
    border-color:
        rgba(21, 154, 156, 0.5);

    color:
        var(--da-teal-dark);
}


/* =========================================================
   REFERENCE SEARCH
   ========================================================= */

.da-reference-search-wrap
{
    margin-bottom:
        1rem;
}


.da-reference-search-label
{
    display:
        block;

    margin-bottom:
        0.4rem;

    color:
        var(--da-navy);

    font-size:
        0.78rem;

    font-weight:
        800;
}


.da-reference-search
{
    display:
        grid;

    grid-template-columns:
        auto minmax(0, 1fr);

    align-items:
        center;

    gap:
        0.6rem;

    min-height:
        48px;

    padding:
        0 0.9rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.75rem;

    background:
        var(--da-lighter);

    color:
        var(--da-muted);
}


.da-reference-search input
{
    width:
        100%;

    min-height:
        46px;

    border:
        0;

    background:
        transparent;

    color:
        var(--da-navy);

    font-size:
        0.88rem;

    outline:
        none;
}


/* =========================================================
   REFERENCE TABS
   ========================================================= */

.da-reference-tabs
{
    display:
        flex;

    flex-wrap:
        wrap;

    gap:
        0.5rem;

    margin-bottom:
        1rem;
}


.da-reference-tab
{
    min-height:
        38px;

    padding:
        0.5rem 0.75rem;

    border:
        1px solid var(--da-border);

    border-radius:
        999px;

    background:
        var(--da-white);

    color:
        var(--da-navy);

    font-size:
        0.74rem;

    font-weight:
        800;
}


.da-reference-tab:hover
{
    border-color:
        rgba(21, 154, 156, 0.5);

    color:
        var(--da-teal-dark);
}


.da-reference-tab.is-active
{
    border-color:
        var(--da-teal);

    background:
        rgba(21, 154, 156, 0.08);

    color:
        var(--da-teal-dark);
}


/* =========================================================
   REFERENCE CONTENT
   ========================================================= */

.da-reference-content
{
    display:
        grid;

    gap:
        1rem;

    max-height:
        640px;

    overflow-y:
        auto;

    padding-right:
        0.25rem;
}


.da-reference-category
{
    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.9rem;

    background:
        var(--da-lighter);
}


.da-reference-category[hidden]
{
    display:
        none !important;
}


.da-reference-category h4
{
    margin:
        0 0 0.8rem;

    color:
        var(--da-navy);

    font-size:
        1rem;

    font-weight:
        800;
}


.da-reference-table-wrap
{
    width:
        100%;

    overflow-x:
        auto;

    border:
        1px solid var(--da-border);

    border-radius:
        0.75rem;

    background:
        var(--da-white);
}


.da-reference-table
{
    width:
        100%;

    min-width:
        650px;

    border-collapse:
        collapse;
}


.da-reference-table th,
.da-reference-table td
{
    padding:
        0.8rem 0.9rem;

    border-bottom:
        1px solid #e8eef4;

    text-align:
        left;

    vertical-align:
        middle;

    font-size:
        0.8rem;
}


.da-reference-table th
{
    background:
        #101827;

    color:
        var(--da-white);

    font-weight:
        800;
}


.da-reference-table td
{
    color:
        var(--da-text);

    font-weight:
        650;
}


.da-reference-table tbody tr:last-child td
{
    border-bottom:
        0;
}


.da-reference-table tbody tr:hover
{
    background:
        rgba(21, 154, 156, 0.035);
}


.da-reference-note
{
    margin-bottom:
        0.8rem;

    padding:
        0.85rem 1rem;

    border-left:
        4px solid var(--da-purple);

    border-radius:
        0.7rem;

    background:
        rgba(111, 66, 193, 0.05);
}


.da-reference-note strong
{
    display:
        block;

    margin-bottom:
        0.3rem;

    color:
        var(--da-navy);
}


.da-reference-note p
{
    margin:
        0;

    color:
        var(--da-text);

    font-size:
        0.82rem;

    line-height:
        1.6;
}


.da-reference-footer
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        space-between;

    gap:
        1rem;

    margin-top:
        1rem;

    padding-top:
        1rem;

    border-top:
        1px solid var(--da-border);
}


.da-reference-footer p
{
    margin:
        0;

    color:
        var(--da-muted);

    font-size:
        0.8rem;
}


.da-reference-chart-link
{
    display:
        inline-flex;

    align-items:
        center;

    gap:
        0.4rem;

    color:
        var(--da-teal-dark);

    font-size:
        0.82rem;

    font-weight:
        800;

    text-decoration:
        none;
}


.da-reference-chart-link:hover
{
    text-decoration:
        underline;
}


/* =========================================================
   PROBLEM COMPLETE
   ========================================================= */

.da-problem-complete
{
    display:
        grid;

    grid-template-columns:
        auto
        minmax(0, 1fr)
        auto;

    align-items:
        center;

    gap:
        1rem;

    margin-top:
        1.4rem;

    padding:
        1.2rem;

    border:
        1px solid rgba(25, 135, 84, 0.25);

    border-radius:
        1rem;

    background:
        rgba(25, 135, 84, 0.06);
}


.da-problem-complete[hidden]
{
    display:
        none !important;
}


.da-problem-complete-icon
{
    color:
        var(--da-green);

    font-size:
        1.8rem;
}


.da-problem-complete-label
{
    margin:
        0 0 0.2rem;

    color:
        var(--da-green);

    font-size:
        0.72rem;

    font-weight:
        800;

    letter-spacing:
        0.08em;

    text-transform:
        uppercase;
}


.da-problem-complete h3
{
    margin:
        0 0 0.2rem;

    color:
        var(--da-navy);

    font-size:
        1.15rem;

    font-weight:
        800;
}


.da-problem-complete p:last-child
{
    margin:
        0;

    color:
        var(--da-muted);

    font-size:
        0.86rem;

    line-height:
        1.55;
}


/* =========================================================
   STATS
   ========================================================= */

.da-stats
{
    display:
        grid;

    grid-template-columns:
        repeat(4, minmax(0, 1fr));

    gap:
        1rem;

    margin-top:
        1.25rem;
}


.da-stat
{
    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.9rem;

    background:
        var(--da-white);

    text-align:
        center;

    box-shadow:
        var(--da-shadow-small);
}


.da-stat span
{
    display:
        block;

    margin-bottom:
        0.3rem;

    color:
        var(--da-muted);

    font-size:
        0.72rem;

    font-weight:
        800;
}


.da-stat strong
{
    color:
        var(--da-navy-dark);

    font-size:
        1.45rem;

    font-weight:
        800;
}


/* =========================================================
   RESULTS
   ========================================================= */

.da-results
{
    margin-top:
        1.5rem;

    padding:
        2rem;

    border:
        1px solid var(--da-border);

    border-radius:
        1.2rem;

    background:
        var(--da-white);

    text-align:
        center;

    box-shadow:
        var(--da-shadow);
}


.da-results[hidden]
{
    display:
        none !important;
}


.da-results-label
{
    margin-bottom:
        0.4rem;

    color:
        var(--da-teal-dark);

    font-size:
        0.75rem;

    font-weight:
        800;

    letter-spacing:
        0.09em;

    text-transform:
        uppercase;
}


.da-results h2
{
    color:
        var(--da-navy);

    font-weight:
        800;
}


.da-results-grid
{
    display:
        grid;

    grid-template-columns:
        repeat(4, minmax(0, 1fr));

    gap:
        1rem;

    margin:
        1.5rem 0;
}


.da-result-item
{
    padding:
        1rem;

    border:
        1px solid var(--da-border);

    border-radius:
        0.85rem;

    background:
        var(--da-lighter);
}


.da-result-item span
{
    display:
        block;

    margin-bottom:
        0.35rem;

    color:
        var(--da-muted);

    font-size:
        0.72rem;

    font-weight:
        800;
}


.da-result-item strong
{
    color:
        var(--da-navy);

    font-size:
        1.45rem;

    font-weight:
        800;
}


.da-result-accuracy strong
{
    color:
        var(--da-teal-dark);
}


/* =========================================================
   INFO CARDS
   ========================================================= */

.da-info
{
    display:
        grid;

    grid-template-columns:
        repeat(4, minmax(0, 1fr));

    gap:
        1rem;

    padding-top:
        4rem;

    padding-bottom:
        4rem;
}


.da-info article
{
    padding:
        1.35rem;

    border:
        1px solid var(--da-border);

    border-radius:
        1rem;

    background:
        var(--da-white);

    box-shadow:
        var(--da-shadow-small);
}


.da-info-icon
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        center;

    width:
        46px;

    height:
        46px;

    margin-bottom:
        1rem;

    border-radius:
        0.8rem;

    background:
        rgba(21, 154, 156, 0.1);

    color:
        var(--da-teal-dark);
}


.da-info h2
{
    margin-bottom:
        0.5rem;

    color:
        var(--da-navy);

    font-size:
        1.08rem;

    font-weight:
        800;
}


.da-info p
{
    margin:
        0;

    color:
        var(--da-muted);

    font-size:
        0.88rem;

    line-height:
        1.65;
}


/* =========================================================
   EXAMPLE SECTION
   ========================================================= */

.da-example-section
{
    padding:
        4.5rem 0;

    background:
        linear-gradient(
            180deg,
            #f7fafc,
            #ffffff
        );
}


.da-example-content
{
    width:
        min(100%, 960px);

    margin:
        0 auto;
}


.da-example-heading
{
    margin-bottom:
        1.5rem;
}


.da-example-heading h2
{
    color:
        var(--da-navy);

    font-weight:
        800;
}


.da-example-heading p:last-child
{
    color:
        var(--da-muted);

    line-height:
        1.7;
}


.da-example-chain
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        center;

    flex-wrap:
        wrap;

    gap:
        0.8rem;

    margin:
        1.5rem 0;

    padding:
        1.5rem;

    border-radius:
        1rem;

    background:
        #101827;

    color:
        var(--da-white);
}


.da-example-factor
{
    min-width:
        110px;

    text-align:
        center;

    font-size:
        0.95rem;

    font-weight:
        800;
}


.da-example-factor hr
{
    margin:
        0.35rem 0;

    border:
        0;

    border-top:
        2px solid rgba(255, 255, 255, 0.85);

    opacity:
        1;
}


.da-example-times
{
    font-size:
        1.3rem;

    font-weight:
        800;
}


.da-example-cancellation
{
    display:
        flex;

    align-items:
        center;

    justify-content:
        center;

    flex-wrap:
        wrap;

    gap:
        0.6rem;

    margin-bottom:
        1rem;

    color:
        var(--da-muted);

    font-size:
        0.82rem;

    font-weight:
        700;
}


.da-cancelled-unit
{
    position:
        relative;

    color:
        var(--da-navy);

    font-weight:
        800;
}


.da-cancelled-unit::after
{
    content:
        "";

    position:
        absolute;

    top:
        50%;

    left:
        -4px;

    right:
        -4px;

    height:
        2px;

    background:
        var(--da-red);

    transform:
        rotate(-12deg);
}


.da-example-result
{
    margin:
        1rem 0;

    padding:
        1rem;

    border:
        1px solid rgba(25, 135, 84, 0.25);

    border-radius:
        0.8rem;

    background:
        rgba(25, 135, 84, 0.06);

    color:
        var(--da-green-dark);

    font-size:
        1.05rem;

    font-weight:
        800;

    text-align:
        center;
}


.da-example-note
{
    margin:
        0;

    padding:
        1rem;

    border-left:
        4px solid var(--da-teal);

    border-radius:
        0.7rem;

    background:
        rgba(21, 154, 156, 0.06);

    color:
        var(--da-text);

    line-height:
        1.65;
}


/* =========================================================
   SEO
   ========================================================= */

.da-seo-section
{
    padding:
        4.5rem 0;
}


.da-seo-content
{
    width:
        min(100%, 920px);

    margin:
        0 auto;
}


.da-seo-content h2
{
    margin-bottom:
        1rem;

    color:
        var(--da-navy);

    font-weight:
        800;
}


.da-seo-content h3
{
    margin-top:
        2rem;

    margin-bottom:
        0.65rem;

    color:
        var(--da-navy);

    font-size:
        1.25rem;

    font-weight:
        800;
}


.da-seo-content p
{
    color:
        var(--da-text);

    line-height:
        1.75;
}


.da-seo-links
{
    display:
        flex;

    flex-wrap:
        wrap;

    align-items:
        center;

    gap:
        0.8rem;

    margin-top:
        2rem;
}


.da-resource-link
{
    color:
        var(--da-teal-dark);

    font-size:
        0.88rem;

    font-weight:
        750;

    text-decoration:
        none;
}


.da-resource-link:hover
{
    text-decoration:
        underline;
}


/* =========================================================
   RESPONSIVE
   ========================================================= */

@media (max-width: 1180px)
{
    .da-mode-tabs
    {
        grid-template-columns:
            repeat(4, minmax(0, 1fr));
    }
}


@media (max-width: 1000px)
{
    .da-factor-card-grid
    {
        grid-template-columns:
            repeat(2, minmax(0, 1fr));
    }


    .da-info
    {
        grid-template-columns:
            repeat(2, minmax(0, 1fr));
    }
}


@media (max-width: 900px)
{
    .da-toolbar
    {
        flex-direction:
            column;

        align-items:
            stretch;
    }


    .da-controls,
    .da-control-group
    {
        width:
            100%;
    }


    .da-unit-goal-panel
    {
        grid-template-columns:
            1fr;
    }


    .da-unit-goal-arrow
    {
        transform:
            rotate(90deg);
    }


    .da-stats,
    .da-results-grid
    {
        grid-template-columns:
            repeat(2, minmax(0, 1fr));
    }


    .da-reference-footer
    {
        flex-direction:
            column;

        align-items:
            flex-start;
    }
}


@media (max-width: 767.98px)
{
    .da-section
    {
        padding:
            3.5rem 1rem;
    }


    .da-card
    {
        padding:
            1.25rem;
    }


    .da-card-top
    {
        flex-direction:
            column;
    }


    .da-card-badges
    {
        justify-content:
            flex-start;
    }


    .da-step-progress
    {
        gap:
            0.25rem;
    }


    .da-step-marker
    {
        min-width:
            58px;
    }


    .da-step-marker span
    {
        width:
            34px;

        height:
            34px;
    }


    .da-workbench-heading,
    .da-factor-tray-heading
    {
        flex-direction:
            column;

        align-items:
            flex-start;
    }


    .da-input-row
    {
        grid-template-columns:
            1fr;
    }


    .da-answer-unit
    {
        min-height:
            48px;
    }


    .da-submit-button
    {
        width:
            100%;
    }


    .da-problem-complete
    {
        grid-template-columns:
            auto minmax(0, 1fr);
    }


    .da-problem-complete .da-next-button
    {
        grid-column:
            1 / -1;

        width:
            100%;
    }
}


@media (max-width: 575.98px)
{
    .da-mode-heading
    {
        flex-direction:
            column;

        align-items:
            flex-start;
    }


    .da-mode-tabs
    {
        grid-template-columns:
            1fr;
    }


    .da-mode-button
    {
        justify-content:
            flex-start;

        padding-left:
            1rem;
    }


    .da-step-progress
    {
        grid-template-columns:
            auto
            minmax(10px, 1fr)
            auto
            minmax(10px, 1fr)
            auto;
    }


    .da-step-marker
    {
        min-width:
            46px;
    }


    .da-step-marker small
    {
        max-width:
            72px;

        font-size:
            0.6rem;
    }


    .da-factor-card-grid,
    .da-choice-grid,
    .da-stats,
    .da-results-grid,
    .da-info
    {
        grid-template-columns:
            1fr;
    }


    .da-action-row
    {
        display:
            grid;

        grid-template-columns:
            1fr;
    }


    .da-secondary-button
    {
        width:
            100%;
    }


    .da-reference-panel
    {
        padding:
            1rem;
    }


    .da-reference-panel-heading
    {
        flex-direction:
            column;

        align-items:
            stretch;
    }


    .da-close-button
    {
        align-self:
            flex-end;
    }
}


/* =========================================================
   REDUCED MOTION
   ========================================================= */

@media (prefers-reduced-motion: reduce)
{
    .da-mode-button,
    .da-select,
    .da-step-marker span,
    .da-progress-bar,
    .da-factor-card,
    .da-step-input,
    .da-choice-button,
    .da-submit-button,
    .da-next-button,
    .da-secondary-button
    {
        transition:
            none;
    }
}

/* =========================================================
   FIX: KEEP SELECTED CONVERSION CHAIN HORIZONTAL
   ========================================================= */

.da-selected-factor-container
{
    display: flex;
    align-items: center;
    gap: 0.75rem;

    width: max-content;
    min-width: max-content;
}


.da-selected-factor
{
    flex: 0 0 auto;
}


/*
 * Keep the starting quantity and every selected factor
 * on the same horizontal dimensional-analysis line.
 */
.da-conversion-chain
{
    display: flex;
    flex-direction: row;
    align-items: center;
    flex-wrap: nowrap;

    width: max-content;
    min-width: max-content;
}


/*
 * If the chain becomes wider than the workbench,
 * scroll horizontally rather than wrapping vertically.
 */
.da-chain-viewport
{
    overflow-x: auto;
    overflow-y: hidden;
}

/* =========================================================
   TWO-STEP WORKFLOW
   ========================================================= */

.da-step-progress.da-step-progress-two
{
    grid-template-columns:
        auto minmax(40px, 1fr) auto;
}


.da-step-progress.da-step-progress-two .da-step-marker
{
    min-width:
        120px;
}


@media (max-width: 575.98px)
{
    .da-step-progress.da-step-progress-two
    {
        grid-template-columns:
            auto minmax(20px, 1fr) auto;
    }


    .da-step-progress.da-step-progress-two .da-step-marker
    {
        min-width:
            80px;
    }
}