```css
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    /* Sprinter Health-inspired brand palette */
    --text: #25284a;
    --text-dark: #202342;
    --muted: #686b83;

    --border: #dedee9;
    --border-light: #e9e9f1;

    --background: #f5f5fb;
    --surface: #ffffff;

    --primary: #302b70;
    --primary-dark: #27235e;
    --primary-light: #efeff9;

    --success: #3f8066;
    --danger: #b94a48;

    --focus: rgba(48, 43, 112, 0.14);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family:
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        Roboto,
        Helvetica,
        Arial,
        sans-serif;

    color: var(--text);
    background: var(--background);
    line-height: 1.6;
    min-height: 100vh;
}


/* ============================================================
   HEADER
   ============================================================ */

.site-header {
    height: 76px;
    background: var(--surface);
    border-bottom: 1px solid #e8ebef;
    display: flex;
    align-items: center;
}

.brand {
    width: min(1080px, calc(100% - 40px));
    margin: 0 auto;
    display: flex;
    align-items: center;
}


.brand-mark {
    width: 34px;
    height: 34px;
    border-radius: 8px;
    background: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 17px;
}

.brand-logo {
    display: block;
    width: 150px;
    height: auto;
}



/* ============================================================
   MAIN ASSESSMENT
   ============================================================ */

.assessment-wrapper {
    width: min(850px, calc(100% - 32px));
    margin: 0 auto;
    padding: 56px 0 90px;
}

.screen {
    display: none;
}

.screen.active {
    display: block;
}


/* ============================================================
   INTRO
   ============================================================ */

.intro-content {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: 16px;
    padding: 52px;
    box-shadow:
        0 10px 30px rgba(40, 38, 75, 0.055);
}

.eyebrow {
    color: var(--primary);
    font-size: 13px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1.2px;
    margin-bottom: 14px;
}

h1 {
    color: var(--text-dark);
    font-size: 38px;
    line-height: 1.18;
    letter-spacing: -1px;
    font-weight: 680;
    margin-bottom: 24px;
}

.intro-text {
    color: #555970;
    font-size: 16px;
    max-width: 700px;
    margin-bottom: 18px;
}

.assessment-details {
    display: flex;
    gap: 44px;
    margin: 32px 0 36px;
    padding-top: 26px;
    border-top: 1px solid var(--border-light);
}

.assessment-details div {
    display: flex;
    flex-direction: column;
    gap: 3px;
}

.assessment-details span {
    color: var(--muted);
    font-size: 13px;
}

.assessment-details strong {
    color: var(--text-dark);
    font-size: 15px;
    font-weight: 650;
}


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

.primary-button,
.secondary-button {
    border: none;
    border-radius: 8px;
    padding: 12px 21px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;

    transition:
        background 0.15s ease,
        transform 0.1s ease,
        box-shadow 0.15s ease,
        border-color 0.15s ease;
}

.primary-button {
    background: var(--primary);
    color: #ffffff;
}

.primary-button:hover {
    background: var(--primary-dark);
    box-shadow:
        0 5px 14px rgba(48, 43, 112, 0.20);
}

.primary-button:active,
.secondary-button:active {
    transform: translateY(1px);
}

.secondary-button {
    background: #ffffff;
    color: var(--text);
    border: 1px solid #d1d2df;
}

.secondary-button:hover {
    background: #f7f7fb;
    border-color: #c2c3d2;
}


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

.assessment-progress {
    display: none;
    margin-bottom: 30px;
}

.assessment-progress.visible {
    display: block;
}

.progress-top {
    display: flex;
    justify-content: space-between;
    margin-bottom: 8px;
    color: var(--muted);
    font-size: 13px;
}

.progress-bar {
    height: 4px;
    width: 100%;
    background: #e3e3ed;
    border-radius: 10px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    width: 20%;
    background: var(--primary);
    border-radius: 10px;
    transition: width 0.25s ease;
}


/* ============================================================
   SECTION HEADINGS
   ============================================================ */

.section-heading {
    display: flex;
    gap: 18px;
    align-items: flex-start;
    margin-bottom: 36px;
}

.section-number {
    color: var(--primary);
    font-size: 14px;
    font-weight: 700;
    letter-spacing: 0.5px;
    padding-top: 7px;
}

.section-heading h2 {
    color: var(--text-dark);
    font-size: 29px;
    line-height: 1.25;
    letter-spacing: -0.5px;
    margin-bottom: 5px;
}

.section-heading p {
    color: var(--muted);
    font-size: 15px;
}


/* ============================================================
   QUESTIONS
   ============================================================ */

.question,
.scenario {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: 12px;
    padding: 25px;
    margin-bottom: 18px;
}

.question label,
.scenario > label {
    display: block;
    color: var(--text-dark);
    font-size: 15px;
    font-weight: 620;
    margin-bottom: 12px;
}

.question label span,
.scenario label span {
    color: var(--danger);
    margin-left: 3px;
}


/* ============================================================
   TEXT INPUTS
   ============================================================ */

input[type="text"],
input[type="email"],
input[type="tel"],
textarea {
    width: 100%;
    border: 1px solid #d0d1dc;
    border-radius: 8px;
    background: #ffffff;
    padding: 12px 13px;
    color: var(--text-dark);
    font-family: inherit;
    font-size: 15px;
    outline: none;

    transition:
        border-color 0.15s ease,
        box-shadow 0.15s ease,
        background 0.15s ease;
}

textarea {
    resize: vertical;
    min-height: 105px;
}

input[type="text"]:focus,
input[type="email"]:focus,
input[type="tel"]:focus,
textarea:focus {
    border-color: var(--primary);
    box-shadow:
        0 0 0 3px var(--focus);
}


/* ============================================================
   OPTIONS
   ============================================================ */

.options {
    display: flex;
    flex-direction: column;
    gap: 9px;
}

.option {
    display: flex !important;
    align-items: flex-start;
    gap: 11px;
    padding: 11px 12px;

    border: 1px solid #e0e0e9;
    border-radius: 8px;

    cursor: pointer;
    font-weight: 400 !important;
    margin-bottom: 0 !important;

    transition:
        background 0.15s ease,
        border-color 0.15s ease;
}

.option:hover {
    background: #f8f8fc;
    border-color: #c9cad8;
}

.option input {
    margin-top: 4px;
    flex: 0 0 auto;
}

.option span {
    color: #41445a;
    font-size: 14px;
    font-weight: 400 !important;
    margin-left: 0 !important;
}


/* ============================================================
   RATING SCALE
   ============================================================ */

.scale {
    display: flex;
    gap: 9px;
}

.scale label {
    margin: 0 !important;
}

.scale input {
    display: none;
}

.scale span {
    width: 45px;
    height: 42px;

    border: 1px solid #d2d3de;
    border-radius: 8px;

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

    color: #4d5064;
    background: #ffffff;

    cursor: pointer;
    font-weight: 500;

    transition:
        all 0.15s ease;
}

.scale span:hover {
    border-color: #aaaac0;
    background: #f8f8fc;
}

.scale input:checked + span {
    background: var(--primary);
    border-color: var(--primary);
    color: #ffffff;
}

.scale-labels {
    display: flex;
    justify-content: space-between;
    max-width: 270px;
    color: var(--muted);
    font-size: 12px;
    margin-top: 7px;
}


/* ============================================================
   SCENARIOS
   ============================================================ */

.scenario-title {
    color: var(--primary);
    font-size: 14px;
    font-weight: 700;
    margin-bottom: 9px;
}

.scenario p {
    color: #55586b;
    font-size: 15px;
    margin-bottom: 21px;
}

.scenario > label {
    margin-top: 10px;
}


/* ============================================================
   FILE UPLOAD
   ============================================================ */

.upload-box {
    border: 1px dashed #b9bacb;
    border-radius: 10px;
    padding: 24px;
    background: #fafaff;
}

.upload-box input {
    width: 100%;
    margin-bottom: 12px;
}

.upload-box p {
    color: #505366;
    font-size: 14px;
    margin-bottom: 3px;
}

.upload-box small {
    color: var(--muted);
    font-size: 12px;
}


/* ============================================================
   DECLARATION
   ============================================================ */

.declaration {
    background: #f7f7fb;
    border: 1px solid #e2e2eb;
    border-radius: 10px;
    padding: 18px;
    margin-bottom: 22px;
}

.checkbox-declaration {
    display: flex;
    gap: 11px;
    align-items: flex-start;
    cursor: pointer;
    font-size: 14px;
    color: #4c4f62;
}

.checkbox-declaration input {
    margin-top: 4px;
    flex: 0 0 auto;
}


/* ============================================================
   NAVIGATION
   ============================================================ */

.navigation {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 28px;
}

.navigation .primary-button:only-child {
    margin-left: auto;
}


/* ============================================================
   SUCCESS
   ============================================================ */

.success-content {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: 16px;
    padding: 60px 52px;
    text-align: center;

    box-shadow:
        0 10px 30px rgba(40, 38, 75, 0.055);
}

.success-icon {
    width: 54px;
    height: 54px;
    border-radius: 50%;

    background: #edf6f1;
    color: var(--success);

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

    margin: 0 auto 25px;

    font-size: 27px;
    font-weight: 700;
}

.success-content h1 {
    margin-bottom: 15px;
}

.success-content p {
    color: #595c6f;
    max-width: 590px;
    margin: 0 auto 14px;
    font-size: 15px;
}


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

@media (max-width: 700px) {

    .site-header {
        height: 68px;
    }

    .brand {
        width: calc(100% - 28px);
    }

    .brand-logo {
        width: 135px;
    }

    .assessment-wrapper {
        width: calc(100% - 22px);
        padding: 30px 0 60px;
    }

    .intro-content,
    .success-content {
        padding: 34px 24px;
    }

    h1 {
        font-size: 30px;
    }

    .section-heading h2 {
        font-size: 25px;
    }

    .question,
    .scenario {
        padding: 20px;
    }

    .assessment-details {
        gap: 28px;
    }

    .navigation {
        gap: 10px;
    }

    .primary-button,
    .secondary-button {
        padding: 11px 16px;
    }
}


@media (max-width: 430px) {

    .assessment-details {
        flex-direction: column;
        gap: 14px;
    }

    .scale {
        gap: 6px;
    }

    .scale span {
        width: 41px;
    }
}
```