/* =========================================================
   TRIGONOMETRIC IDENTITIES GUIDE
   Mirrors Law of Cosines styling
   ========================================================= */

:root
{
    --ti-navy: #0f172a;
    --ti-slate: #475569;
    --ti-muted: #64748b;

    --ti-border: #d7e2ec;

    --ti-white: #ffffff;
    --ti-surface: #f8fafc;

    --ti-teal: #0f766e;
    --ti-teal-bright: #159e9c;
    --ti-teal-soft: #ecfdf5;

    --ti-blue: #2563eb;
    --ti-blue-soft: #eff6ff;

    --ti-gold: #d97706;
    --ti-gold-soft: #fff7ed;

    --ti-purple: #7c3aed;
    --ti-purple-soft: #f5f3ff;

    --ti-green: #15803d;
    --ti-green-soft: #f0fdf4;

    --ti-red: #b91c1c;
    --ti-red-soft: #fef2f2;

    --ti-shadow:
        0 1rem 2.5rem
        rgba(
            15,
            23,
            42,
            0.08
        );

    --ti-shadow-small:
        0 0.75rem 2rem
        rgba(
            15,
            23,
            42,
            0.06
        );
}


/* =========================================================
   BASE
   ========================================================= */

#trigonometric-identities-guide
{
    scroll-margin-top: 5rem;
}

.ti-intro,
.ti-section,
.ti-family-section,
.ti-derivation-card,
.ti-worked-example,
.ti-final-card,
.ti-related-section
{
    color: var(--ti-slate);

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

.ti-intro h2,
.ti-section-heading h2,
.ti-family-heading h3,
.ti-derivation-heading h4,
.ti-worked-heading h4,
.ti-final-card h2,
.ti-practice-cta h2,
.ti-related-section h2
{
    color: var(--ti-navy);

    font-weight: 800;

    letter-spacing: -0.03em;

    line-height: 1.15;
}

.ti-intro h2,
.ti-section-heading h2
{
    font-size:
        clamp(
            1.8rem,
            4vw,
            2.55rem
        );
}

.ti-intro .lead
{
    margin-bottom: 1rem;

    color: var(--ti-slate);

    font-size:
        clamp(
            1.05rem,
            1.8vw,
            1.2rem
        );

    line-height: 1.75;
}

.ti-intro > p:not(.lead):not(.ti-eyebrow)
{
    color: var(--ti-slate);

    line-height: 1.75;
}

.ti-section
{
    margin-top:
        clamp(
            3.5rem,
            7vw,
            5.5rem
        );
}

.ti-section-heading
{
    max-width: 50rem;

    margin-bottom: 1.5rem;
}

.ti-section-heading p
{
    margin-top: 0.7rem;
    margin-bottom: 0;

    color: var(--ti-slate);

    font-size: 1.02rem;

    line-height: 1.75;
}

.ti-eyebrow,
.ti-section-eyebrow,
.ti-family-eyebrow,
.ti-card-label
{
    margin:
        0
        0
        0.45rem;

    color: var(--ti-teal);

    font-size: 0.76rem;
    font-weight: 800;

    letter-spacing: 0.1em;

    line-height: 1.3;

    text-transform: uppercase;
}


/* =========================================================
   DEFINITION / INTRO CARDS
   ========================================================= */

.ti-definition-card
{
    display: flex;

    gap: 1rem;

    align-items: flex-start;

    margin-bottom: 1.5rem;

    padding:
        1.15rem
        1.25rem;

    background: var(--ti-teal-soft);

    border:
        1px solid
        rgba(
            13,
            148,
            136,
            0.24
        );

    border-radius: 1rem;
}

.ti-definition-icon,
.ti-why-icon,
.ti-tip-icon,
.ti-warning-icon,
.ti-verify-rule-icon,
.ti-mistake-icon,
.ti-related-icon
{
    display: grid;

    flex:
        0
        0
        2.7rem;

    width: 2.7rem;
    height: 2.7rem;

    place-items: center;

    border-radius: 0.8rem;
}

.ti-definition-icon,
.ti-tip-icon,
.ti-verify-rule-icon,
.ti-related-icon
{
    color: var(--ti-teal);

    background:
        rgba(
            20,
            184,
            166,
            0.13
        );
}

.ti-definition-text
{
    margin: 0;

    color: var(--ti-slate);

    line-height: 1.65;
}

.ti-comparison-grid
{
    display: grid;

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

    gap: 1rem;

    margin-bottom: 1.5rem;
}

.ti-comparison-card
{
    min-width: 0;

    padding: 1.25rem;

    background: var(--ti-white);

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

    border-radius: 1rem;

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

.ti-comparison-card p
{
    margin-bottom: 0;

    color: var(--ti-slate);

    line-height: 1.65;
}

.ti-comparison-math
{
    display: grid;

    min-height: 4.4rem;

    margin:
        0.8rem
        0;

    padding: 0.75rem;

    place-items: center;

    color: var(--ti-teal);

    background: var(--ti-surface);

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

    border-radius: 0.8rem;
}

.ti-why-card
{
    padding:
        clamp(
            1.4rem,
            4vw,
            2rem
        );

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

    border:
        1px solid
        rgba(
            13,
            148,
            136,
            0.22
        );

    border-radius: 1.2rem;
}

.ti-why-heading
{
    display: flex;

    gap: 0.85rem;

    align-items: flex-start;

    margin-bottom: 0.9rem;
}

.ti-why-icon
{
    color: var(--ti-gold);

    background:
        rgba(
            245,
            158,
            11,
            0.14
        );
}

.ti-why-heading h3
{
    margin:
        0
        0
        0.35rem;

    color: var(--ti-navy);

    font-size: 1.05rem;
    font-weight: 800;
}

.ti-why-card > p
{
    color: var(--ti-slate);

    line-height: 1.7;
}


/* =========================================================
   FAMILY SECTIONS
   ========================================================= */

.ti-family-section
{
    margin-top:
        clamp(
            3.5rem,
            7vw,
            5rem
        );
}

.ti-family-heading
{
    max-width: 50rem;

    margin-bottom: 1.5rem;
}

.ti-family-heading h3
{
    margin:
        0
        0
        0.55rem;

    font-size:
        clamp(
            1.45rem,
            3vw,
            2rem
        );
}

.ti-family-heading p
{
    margin-bottom: 0.65rem;

    color: var(--ti-slate);

    line-height: 1.7;
}


/* =========================================================
   IDENTITY GRIDS / CARDS
   ========================================================= */

.ti-identity-grid,
.ti-pythagorean-grid,
.ti-reference-grid
{
    display: grid;

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

    gap: 1rem;
}

.ti-quotient-grid,
.ti-rearrange-grid,
.ti-verify-comparison-grid
{
    display: grid;

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

    gap: 1rem;
}

.ti-identity-card,
.ti-pythagorean-card,
.ti-quotient-card,
.ti-rearrange-card,
.ti-reference-card
{
    min-width: 0;

    padding: 1.15rem;

    background: var(--ti-white);

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

    border-radius: 1rem;

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

.ti-identity-name
{
    margin-bottom: 0.8rem;

    color: var(--ti-navy);

    font-size: 0.92rem;
    font-weight: 800;

    text-align: center;
}

.ti-identity-math
{
    display: grid;

    min-width: 0;
    min-height: 5rem;

    padding: 0.7rem;

    place-items: center;

    color: var(--ti-teal);

    background: var(--ti-surface);

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

    border-radius: 0.8rem;
}

.ti-secondary-math
{
    margin-top: 0.75rem;
}

.ti-quotient-card
{
    text-align: center;
}

.ti-quotient-card p
{
    margin:
        0.8rem
        0
        0;

    color: var(--ti-slate);

    line-height: 1.65;
}


/* =========================================================
   TIP / WARNING
   ========================================================= */

.ti-tip-card,
.ti-warning-card
{
    display: flex;

    gap: 1rem;

    align-items: flex-start;

    padding:
        1.15rem
        1.25rem;

    border-radius: 1rem;
}

.ti-tip-card
{
    background: var(--ti-teal-soft);

    border:
        1px solid
        rgba(
            13,
            148,
            136,
            0.24
        );
}

.ti-warning-card
{
    background: var(--ti-gold-soft);

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

.ti-warning-icon
{
    color: var(--ti-gold);

    background:
        rgba(
            245,
            158,
            11,
            0.14
        );
}

.ti-tip-title,
.ti-warning-title
{
    margin:
        0
        0
        0.25rem;

    color: var(--ti-navy);

    font-weight: 800;
}

.ti-tip-card p,
.ti-warning-card p
{
    color: var(--ti-slate);

    line-height: 1.65;
}


/* =========================================================
   REWRITE CARDS
   ========================================================= */

.ti-rewrite-card
{
    padding:
        clamp(
            1.3rem,
            3.5vw,
            1.9rem
        );

    background: var(--ti-white);

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

    border-radius: 1.2rem;

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

.ti-rewrite-card h4
{
    margin:
        0
        0
        0.55rem;

    color: var(--ti-navy);

    font-size: 1.05rem;
    font-weight: 800;
}

.ti-rewrite-card > p
{
    color: var(--ti-slate);

    line-height: 1.7;
}

.ti-rewrite-example
{
    display: flex;

    gap: 1rem;

    align-items: center;
    justify-content: center;

    flex-wrap: wrap;

    margin-top: 1.25rem;
}

.ti-rewrite-example > div:not(.ti-rewrite-arrow)
{
    display: grid;

    min-width: 10rem;
    min-height: 5rem;

    padding: 0.75rem;

    place-items: center;

    text-align: center;

    background: var(--ti-surface);

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

    border-radius: 0.8rem;
}

.ti-rewrite-label
{
    display: block;

    margin-bottom: 0.4rem;

    color: var(--ti-muted);

    font-size: 0.72rem;
    font-weight: 800;

    letter-spacing: 0.08em;

    text-transform: uppercase;
}

.ti-rewrite-arrow
{
    color: var(--ti-teal);

    font-size: 1.2rem;
}


/* =========================================================
   DERIVATION CARDS
   ========================================================= */

.ti-derivation-card,
.ti-connection-card,
.ti-final-card
{
    padding:
        clamp(
            1.4rem,
            4vw,
            2rem
        );

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

    border:
        1px solid
        rgba(
            13,
            148,
            136,
            0.22
        );

    border-radius: 1.2rem;
}

.ti-derivation-heading
{
    margin-bottom: 1rem;
}

.ti-derivation-heading h4
{
    margin: 0;

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

.ti-derivation-card > p,
.ti-connection-card > p
{
    color: var(--ti-slate);

    line-height: 1.7;
}

.ti-derivation-math
{
    display: grid;

    min-height: 4.4rem;

    margin:
        0.8rem
        0;

    padding: 0.75rem;

    place-items: center;

    color: var(--ti-teal);

    background:
        rgba(
            255,
            255,
            255,
            0.82
        );

    border:
        1px solid
        rgba(
            148,
            163,
            184,
            0.25
        );

    border-radius: 0.8rem;
}

.ti-substitution-row
{
    display: grid;

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

    gap: 0.85rem;

    margin:
        1rem
        0;
}

.ti-substitution-row > div
{
    display: grid;

    min-height: 4rem;

    padding: 0.7rem;

    place-items: center;

    color: var(--ti-teal);

    background:
        rgba(
            255,
            255,
            255,
            0.82
        );

    border:
        1px solid
        rgba(
            148,
            163,
            184,
            0.25
        );

    border-radius: 0.8rem;
}

.ti-derivation-steps
{
    display: grid;

    gap: 0.6rem;

    margin-top: 1rem;
}

.ti-derivation-step
{
    display: flex;

    gap: 0.85rem;

    align-items: center;

    min-width: 0;

    padding: 1rem;

    background:
        rgba(
            255,
            255,
            255,
            0.82
        );

    border:
        1px solid
        rgba(
            148,
            163,
            184,
            0.25
        );

    border-radius: 0.9rem;
}

.ti-derivation-step > span,
.ti-step-number,
.ti-strategy-number
{
    display: grid;

    flex:
        0
        0
        2rem;

    width: 2rem;
    height: 2rem;

    place-items: center;

    color: var(--ti-white);

    font-size: 0.78rem;
    font-weight: 800;

    background: var(--ti-teal);

    border-radius: 50%;
}

.ti-derivation-step > div
{
    min-width: 0;

    color: var(--ti-teal);
}

.ti-derivation-arrow
{
    color: var(--ti-muted);

    text-align: center;
}

.ti-derivation-final
{
    background:
        rgba(
            255,
            255,
            255,
            0.92
        );
}

.ti-notation-note
{
    margin-top: 1rem;

    padding:
        1rem
        1.1rem;

    background: var(--ti-gold-soft);

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

    border-radius: 0.9rem;
}

.ti-notation-note p
{
    color: var(--ti-slate);

    line-height: 1.65;
}

.ti-identity-conversion-grid
{
    display: grid;

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

    gap: 0.85rem;

    margin-top: 1rem;
}

.ti-identity-conversion-grid > div
{
    display: grid;

    min-width: 0;
    min-height: 4.4rem;

    padding: 0.7rem;

    place-items: center;

    color: var(--ti-teal);

    background:
        rgba(
            255,
            255,
            255,
            0.82
        );

    border:
        1px solid
        rgba(
            148,
            163,
            184,
            0.25
        );

    border-radius: 0.8rem;
}

.ti-derivation-result
{
    display: flex;

    gap: 1rem;

    align-items: center;
    justify-content: space-between;

    margin-top: 1rem;

    padding:
        0.9rem
        1rem;

    color: var(--ti-teal);

    background:
        rgba(
            255,
            255,
            255,
            0.78
        );

    border:
        1px solid
        rgba(
            148,
            163,
            184,
            0.25
        );

    border-radius: 0.8rem;
}

.ti-derivation-result span
{
    flex: 0 0 auto;

    color: var(--ti-navy);

    font-size: 0.72rem;
    font-weight: 800;

    letter-spacing: 0.08em;

    text-transform: uppercase;
}


/* =========================================================
   CONNECTION SUMMARY
   ========================================================= */

.ti-connection-card h4
{
    margin:
        0
        0
        0.55rem;

    color: var(--ti-navy);

    font-size: 1.05rem;
    font-weight: 800;
}

.ti-connection-flow
{
    margin:
        1rem
        0;
}

.ti-connection-start
{
    display: grid;

    min-height: 5rem;

    padding: 0.75rem;

    place-items: center;

    color: var(--ti-teal);

    background:
        rgba(
            255,
            255,
            255,
            0.82
        );

    border:
        1px solid
        rgba(
            148,
            163,
            184,
            0.25
        );

    border-radius: 0.8rem;
}

.ti-connection-branches
{
    display: grid;

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

    gap: 1rem;

    margin-top: 1rem;
}

.ti-connection-branch
{
    padding: 1rem;

    text-align: center;

    background:
        rgba(
            255,
            255,
            255,
            0.82
        );

    border:
        1px solid
        rgba(
            148,
            163,
            184,
            0.25
        );

    border-radius: 0.9rem;
}

.ti-connection-branch span
{
    display: block;

    margin-bottom: 0.45rem;

    color: var(--ti-muted);

    font-size: 0.8rem;
    font-weight: 700;
}

.ti-connection-branch i
{
    margin-bottom: 0.45rem;

    color: var(--ti-teal);
}


/* =========================================================
   APPLICATION / REARRANGING
   ========================================================= */

.ti-application-section,
.ti-choice-section
{
    margin-top:
        clamp(
            3.5rem,
            7vw,
            5rem
        );
}

.ti-rearrange-card
{
    text-align: center;
}

.ti-rearrange-arrow
{
    margin:
        0.5rem
        0;

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


/* =========================================================
   WORKED EXAMPLES
   ========================================================= */

.ti-worked-example
{
    padding:
        clamp(
            1.3rem,
            3.5vw,
            1.9rem
        );

    background: var(--ti-white);

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

    border-radius: 1.2rem;

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

.ti-worked-heading
{
    margin-bottom: 1rem;
}

.ti-worked-heading h4
{
    margin: 0;

    font-size:
        clamp(
            1.25rem,
            3vw,
            1.6rem
        );
}

.ti-worked-problem
{
    display: grid;

    min-height: 5rem;

    margin-bottom: 1rem;

    padding: 0.8rem;

    place-items: center;

    color: var(--ti-teal);

    background: var(--ti-surface);

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

    border-radius: 0.8rem;
}

.ti-worked-steps
{
    min-width: 0;

    padding: 1.15rem;

    background: var(--ti-surface);

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

    border-radius: 1rem;
}

.ti-worked-step
{
    display: flex;

    gap: 0.85rem;

    align-items: flex-start;

    margin-bottom: 1rem;

    color: var(--ti-slate);
}

.ti-worked-step:last-child
{
    margin-bottom: 0;
}

.ti-worked-step > div
{
    flex: 1;

    min-width: 0;

    color: var(--ti-teal);
}

.ti-worked-step p
{
    margin:
        0
        0
        0.4rem;

    color: var(--ti-slate);

    line-height: 1.6;
}


/* =========================================================
   STRATEGY / PROCESS GRIDS
   ========================================================= */

.ti-strategy-grid,
.ti-verify-process-grid
{
    display: grid;

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

    gap: 0.85rem;
}

.ti-strategy-grid article,
.ti-verify-process-grid article
{
    min-width: 0;

    padding: 1rem;

    background: var(--ti-white);

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

    border-radius: 0.9rem;

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

.ti-strategy-number
{
    margin-bottom: 0.75rem;
}

.ti-strategy-grid h4,
.ti-verify-process-grid h4
{
    margin:
        0
        0
        0.45rem;

    color: var(--ti-navy);

    font-size: 0.95rem;
    font-weight: 800;
}

.ti-strategy-grid p,
.ti-verify-process-grid p
{
    margin: 0;

    color: var(--ti-slate);

    font-size: 0.86rem;

    line-height: 1.55;
}


/* =========================================================
   VERIFYING IDENTITIES
   ========================================================= */

.ti-verify-rule-card
{
    display: flex;

    gap: 1rem;

    align-items: flex-start;

    margin-bottom: 1.5rem;

    padding:
        1.15rem
        1.25rem;

    background: var(--ti-teal-soft);

    border:
        1px solid
        rgba(
            13,
            148,
            136,
            0.24
        );

    border-radius: 1rem;
}

.ti-verify-rule-card h3
{
    margin:
        0
        0
        0.35rem;

    color: var(--ti-navy);

    font-size: 1.05rem;
    font-weight: 800;
}

.ti-verify-rule-card p
{
    color: var(--ti-slate);

    line-height: 1.65;
}

.ti-verify-good-card,
.ti-verify-bad-card
{
    min-width: 0;

    padding: 1.15rem;

    background: var(--ti-white);

    border-radius: 1rem;

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

.ti-verify-good-card
{
    border:
        1px solid
        rgba(
            21,
            128,
            61,
            0.25
        );
}

.ti-verify-bad-card
{
    border:
        1px solid
        rgba(
            185,
            28,
            28,
            0.22
        );
}

.ti-verify-good-card h4,
.ti-verify-bad-card h4
{
    margin:
        0
        0
        0.55rem;

    color: var(--ti-navy);

    font-size: 1rem;
    font-weight: 800;
}

.ti-verify-bad-card > p
{
    color: var(--ti-slate);

    line-height: 1.65;
}

.ti-verify-example-math
{
    display: grid;

    min-height: 3.8rem;

    padding: 0.65rem;

    place-items: center;

    color: var(--ti-teal);

    background: var(--ti-surface);

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

    border-radius: 0.75rem;
}

.ti-verify-arrow
{
    margin:
        0.4rem
        0;

    color: var(--ti-muted);

    text-align: center;
}

.ti-warning-inline
{
    display: flex;

    gap: 0.7rem;

    align-items: flex-start;

    margin-top: 1rem;

    padding: 0.85rem;

    color: var(--ti-red);

    background: var(--ti-red-soft);

    border:
        1px solid
        rgba(
            185,
            28,
            28,
            0.16
        );

    border-radius: 0.8rem;
}

.ti-verified-box
{
    display: flex;

    gap: 0.7rem;

    align-items: center;

    margin-top: 1rem;

    padding:
        0.9rem
        1rem;

    color: var(--ti-green);

    background: var(--ti-green-soft);

    border:
        1px solid
        rgba(
            21,
            128,
            61,
            0.22
        );

    border-radius: 0.8rem;

    font-weight: 700;
}


/* =========================================================
   COMMON MISTAKES
   ========================================================= */

.ti-mistake-grid
{
    display: grid;

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

    gap: 1rem;
}

.ti-mistake-card
{
    min-width: 0;

    padding: 1.15rem;

    background: var(--ti-white);

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

    border-radius: 1rem;

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

.ti-mistake-icon
{
    margin-bottom: 0.8rem;

    color: var(--ti-gold);

    background: var(--ti-gold-soft);
}

.ti-mistake-card h3
{
    margin:
        0
        0
        0.45rem;

    color: var(--ti-navy);

    font-size: 1rem;
    font-weight: 800;
}

.ti-mistake-card p
{
    margin: 0;

    color: var(--ti-slate);

    font-size: 0.9rem;

    line-height: 1.65;
}

.ti-mistake-math
{
    display: grid;

    min-height: 4rem;

    margin-top: 0.8rem;

    padding: 0.65rem;

    place-items: center;

    color: var(--ti-teal);

    background: var(--ti-surface);

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

    border-radius: 0.75rem;
}


/* =========================================================
   MASTER REFERENCE
   ========================================================= */

.ti-reference-card > div
{
    color: var(--ti-teal);
}


/* =========================================================
   FINAL CHECKLIST
   ========================================================= */

.ti-final-card h2
{
    margin-bottom: 1.25rem;

    font-size:
        clamp(
            1.55rem,
            3vw,
            2rem
        );
}

.ti-final-list
{
    display: grid;

    gap: 0.65rem;

    margin: 0;

    padding-left: 1.35rem;
}

.ti-final-list li
{
    padding-left: 0.25rem;

    color: var(--ti-slate);

    line-height: 1.6;
}

.ti-final-list li::marker
{
    color: var(--ti-teal);

    font-weight: 800;
}


/* =========================================================
   PRACTICE CTA
   ========================================================= */

.ti-practice-cta
{
    display: grid;

    grid-template-columns:
        minmax(0, 1.2fr)
        auto;

    gap: 1.4rem;

    align-items: center;

    padding:
        clamp(
            1.5rem,
            4vw,
            2.2rem
        );

    background: var(--ti-navy);

    border-radius: 1.25rem;

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

.ti-practice-cta h2
{
    margin:
        0
        0
        0.65rem;

    color: var(--ti-white);

    font-size:
        clamp(
            1.5rem,
            3vw,
            2rem
        );
}

.ti-practice-cta p
{
    margin: 0;

    color: #cbd5e1;

    line-height: 1.7;
}

.ti-practice-cta .ti-card-label
{
    color: #5eead4;
}


/* =========================================================
   RELATED RESOURCES
   ========================================================= */

.ti-related-section
{
    margin-top:
        clamp(
            3.5rem,
            7vw,
            5.5rem
        );
}

.ti-related-section h2
{
    font-size:
        clamp(
            1.75rem,
            4vw,
            2.4rem
        );
}

.ti-related-grid
{
    display: grid;

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

    gap: 1rem;
}

.ti-related-card
{
    display: flex;

    flex-direction: column;

    min-width: 0;
    min-height: 100%;

    padding: 1.2rem;

    color: var(--ti-navy);

    text-decoration: none;

    background: var(--ti-white);

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

    border-radius: 1rem;

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

    transition:
        transform 180ms ease,
        border-color 180ms ease,
        box-shadow 180ms ease;
}

.ti-related-card:hover
{
    color: var(--ti-navy);

    text-decoration: none;

    border-color:
        rgba(
            13,
            148,
            136,
            0.5
        );

    box-shadow: var(--ti-shadow);

    transform:
        translateY(-3px);
}

.ti-related-icon
{
    margin-bottom: 0.85rem;
}

.ti-related-card h3
{
    margin:
        0
        0
        0.45rem;

    color: inherit;

    font-size: 1rem;
    font-weight: 800;

    line-height: 1.4;
}

.ti-related-card p
{
    margin: 0;

    color: var(--ti-slate);

    font-size: 0.89rem;

    line-height: 1.6;
}


/* =========================================================
   MATHJAX SAFETY
   ========================================================= */

.ti-comparison-math mjx-container,
.ti-identity-math mjx-container,
.ti-rewrite-example mjx-container,
.ti-derivation-math mjx-container,
.ti-substitution-row mjx-container,
.ti-derivation-step mjx-container,
.ti-identity-conversion-grid mjx-container,
.ti-derivation-result mjx-container,
.ti-connection-start mjx-container,
.ti-connection-branch mjx-container,
.ti-worked-problem mjx-container,
.ti-worked-step mjx-container,
.ti-verify-example-math mjx-container,
.ti-mistake-math mjx-container,
.ti-reference-card mjx-container
{
    max-width: 100%;

    margin: 0 !important;

    overflow-x: auto;
    overflow-y: hidden;
}


/* =========================================================
   GUIDE CONTACT CTA OVERRIDE
   ========================================================= */

#guideContactCtaTitle
{
    color: #ffffff !important;
}


/* =========================================================
   ACCESSIBILITY
   ========================================================= */

.ti-related-card:focus-visible,
.ti-practice-cta a:focus-visible
{
    outline:
        3px solid
        rgba(
            37,
            99,
            235,
            0.38
        );

    outline-offset: 4px;
}


/* =========================================================
   TABLET
   ========================================================= */

@media (max-width: 991.98px)
{
    .ti-identity-grid,
    .ti-pythagorean-grid,
    .ti-reference-grid
    {
        grid-template-columns: 1fr;
    }

    .ti-strategy-grid,
    .ti-verify-process-grid
    {
        grid-template-columns:
            repeat(
                2,
                minmax(0, 1fr)
            );
    }

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

    .ti-practice-cta
    {
        grid-template-columns: 1fr;
    }

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


/* =========================================================
   MOBILE
   ========================================================= */

@media (max-width: 767.98px)
{
    #trigonometric-identities-guide
    {
        overflow-x: hidden;
    }

    .ti-section,
    .ti-family-section,
    .ti-application-section,
    .ti-choice-section,
    .ti-related-section
    {
        margin-top: 3.5rem;
    }

    .ti-intro .lead,
    .ti-section-heading p
    {
        font-size: 1rem;

        line-height: 1.7;
    }


    /* -----------------------------------------
       Grids
       ----------------------------------------- */

    .ti-comparison-grid,
    .ti-quotient-grid,
    .ti-rearrange-grid,
    .ti-substitution-row,
    .ti-connection-branches,
    .ti-identity-conversion-grid,
    .ti-verify-comparison-grid,
    .ti-strategy-grid,
    .ti-verify-process-grid,
    .ti-mistake-grid,
    .ti-related-grid
    {
        grid-template-columns: 1fr;
    }


    /* -----------------------------------------
       Intro / info cards
       ----------------------------------------- */

    .ti-definition-card,
    .ti-tip-card,
    .ti-warning-card,
    .ti-verify-rule-card
    {
        padding: 1rem;
    }


    /* -----------------------------------------
       Gradient cards
       ----------------------------------------- */

    .ti-why-card,
    .ti-derivation-card,
    .ti-connection-card,
    .ti-final-card
    {
        padding: 1.15rem;

        border-radius: 1rem;
    }


    /* -----------------------------------------
       Derivations
       ----------------------------------------- */

    .ti-derivation-step
    {
        align-items: flex-start;

        flex-direction: column;
    }

    .ti-derivation-result
    {
        align-items: flex-start;

        flex-direction: column;
    }


    /* -----------------------------------------
       Rewrite flow
       ----------------------------------------- */

    .ti-rewrite-example
    {
        flex-direction: column;
    }

    .ti-rewrite-arrow
    {
        transform: rotate(90deg);
    }


    /* -----------------------------------------
       Worked examples
       ----------------------------------------- */

    .ti-worked-example
    {
        padding: 1.1rem;

        border-radius: 1rem;
    }

    .ti-worked-steps
    {
        padding: 1rem;
    }

    .ti-worked-step
    {
        flex-direction: column;
    }


    /* -----------------------------------------
       Practice CTA
       ----------------------------------------- */

    .ti-practice-cta
    {
        padding: 1.25rem;

        border-radius: 1rem;
    }

    .ti-practice-cta .btn
    {
        width: 100%;

        text-align: center;
    }


    /* -----------------------------------------
       Related
       ----------------------------------------- */

    .ti-related-card
    {
        padding: 1.05rem;
    }


    /* -----------------------------------------
       Math
       ----------------------------------------- */

    .ti-comparison-math mjx-container,
    .ti-identity-math mjx-container,
    .ti-rewrite-example mjx-container,
    .ti-derivation-math mjx-container,
    .ti-substitution-row mjx-container,
    .ti-derivation-step mjx-container,
    .ti-identity-conversion-grid mjx-container,
    .ti-derivation-result mjx-container,
    .ti-connection-start mjx-container,
    .ti-connection-branch mjx-container,
    .ti-worked-problem mjx-container,
    .ti-worked-step mjx-container,
    .ti-verify-example-math mjx-container,
    .ti-mistake-math mjx-container,
    .ti-reference-card mjx-container
    {
        width: 100%;
        max-width: 100%;

        overflow-x: auto;
        overflow-y: hidden;
    }
}


/* =========================================================
   SMALL MOBILE
   ========================================================= */

@media (max-width: 479.98px)
{
    .ti-why-card,
    .ti-derivation-card,
    .ti-connection-card,
    .ti-final-card,
    .ti-practice-cta,
    .ti-worked-example
    {
        padding: 1rem;
    }

    .ti-definition-card,
    .ti-tip-card,
    .ti-warning-card,
    .ti-verify-rule-card
    {
        flex-direction: column;
    }
}


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

@media (prefers-reduced-motion: reduce)
{
    .ti-related-card
    {
        transition: none;
    }

    .ti-related-card:hover
    {
        transform: none;
    }
}


/* =========================================================
   PRINT
   ========================================================= */

@media print
{
    .ti-practice-cta,
    .ti-related-section
    {
        display: none !important;
    }

    .ti-definition-card,
    .ti-comparison-card,
    .ti-identity-card,
    .ti-pythagorean-card,
    .ti-quotient-card,
    .ti-rearrange-card,
    .ti-derivation-card,
    .ti-connection-card,
    .ti-worked-example,
    .ti-verify-rule-card,
    .ti-verify-good-card,
    .ti-verify-bad-card,
    .ti-mistake-card,
    .ti-reference-card,
    .ti-final-card
    {
        break-inside: avoid;

        box-shadow: none;
    }
}

/* =========================================================
   SMALL MATH SPACING FIXES
   ========================================================= */


/* Quick reference cards */

.ti-reference-card mjx-container + mjx-container
{
    margin-top: 0.35rem !important;
}


/* Common mistake card with tangent / cotangent */

.ti-mistake-math mjx-container + mjx-container
{
    margin-top: 0.45rem !important;
}


/* Worked steps with stacked equations */

.ti-worked-step mjx-container + mjx-container
{
    margin-top: 0.45rem !important;
}

/* Long identity formulas need more horizontal room */

.ti-family-section .ti-identity-grid
{
    grid-template-columns:
        repeat(
            2,
            minmax(0, 1fr)
        );
}

.ti-identity-math
{
    width: 100%;
    min-width: 0;

    overflow-x: auto;
    overflow-y: hidden;
}

.ti-identity-math mjx-container
{
    width: 100%;
    max-width: 100%;

    overflow-x: auto;
    overflow-y: hidden;
}

@media (max-width: 767.98px)
{
    .ti-family-section .ti-identity-grid
    {
        grid-template-columns: 1fr;
    }
}