:root {
    --sample-navy: #08175c;
    --sample-blue: #1769aa;
    --sample-red: #d84b32;
    --sample-gold: #f0aa2c;
    --sample-ink: #172033;
    --sample-muted: #667085;
    --sample-surface: #f5f7fb;
}

.sample-problems-page,
.sample-problems-page * {
    box-sizing: border-box;
}

.sample-problems-page {
    width: min(1200px, calc(100% - 40px));
    margin: 0 auto;
    padding: 48px 0 72px;
    color: var(--sample-ink);
    font-family: Arial, Helvetica, sans-serif;
    text-align: left;
}

.sample-problems-hero {
    display: flex;
    align-items: flex-end;
    justify-content: space-between;
    gap: 32px;
    padding: 44px;
    border-radius: 18px;
    background: linear-gradient(125deg, var(--sample-navy), #16398a);
    color: #fff;
    box-shadow: 0 18px 42px rgba(8, 23, 92, .16);
}

.sample-kicker {
    display: block;
    margin-bottom: 8px;
    color: var(--sample-red);
    font-size: .76rem;
    font-weight: 800;
    letter-spacing: .12em;
    line-height: 1.4;
    text-transform: uppercase;
}

.sample-problems-hero .sample-kicker,
.problem-week-card .sample-kicker {
    color: #ffd37a;
}

.sample-problems-hero h1 {
    margin: 0 0 14px;
    color: #fff;
    font-size: clamp(2.25rem, 5vw, 4.2rem);
    line-height: 1.04;
    letter-spacing: -.04em;
}

.sample-problems-hero p {
    max-width: 720px;
    margin: 0;
    color: #dce5ff;
    font-size: 1.08rem;
    line-height: 1.65;
}

.sample-hero-highlight {
    flex: 0 0 auto;
    min-width: 154px;
    padding: 18px 21px;
    border: 1px solid rgba(255,255,255,.2);
    border-radius: 12px;
    background: rgba(255,255,255,.09);
}

.sample-hero-highlight strong,
.sample-hero-highlight span {
    display: block;
}

.sample-hero-highlight strong {
    color: #fff;
    font-size: 2.1rem;
}

.sample-hero-highlight span {
    margin-top: 3px;
    color: #dce5ff;
    font-size: .84rem;
}

.problem-week-card {
    display: grid;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    gap: 24px;
    margin: 28px 0 72px;
    padding: 28px 32px;
    border-radius: 16px;
    background: linear-gradient(115deg, #b53c28, var(--sample-red));
    color: #fff;
    box-shadow: 0 12px 30px rgba(181, 60, 40, .2);
}

.problem-week-icon {
    width: 62px;
    height: 62px;
    display: grid;
    place-items: center;
    border: 2px solid rgba(255,255,255,.65);
    border-radius: 50%;
    background: rgba(255,255,255,.1);
    color: #fff;
    font-size: 2rem;
    font-weight: 800;
}

.problem-week-card h2 {
    margin: 0 0 6px;
    color: #fff;
    font-size: 1.75rem;
}

.problem-week-card p {
    margin: 0;
    color: #fff3ef;
    line-height: 1.55;
}

.sample-button {
    min-height: 48px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 20px;
    border: 2px solid transparent;
    border-radius: 8px;
    font-size: .94rem;
    font-weight: 800;
    line-height: 1.2;
    text-decoration: none;
    white-space: nowrap;
    transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}

.sample-button:hover,
.sample-button:focus-visible {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(8,23,92,.16);
}

.sample-button-light { background: #fff; color: var(--sample-navy); }
.sample-button-primary { background: var(--sample-red); color: #fff; }
.sample-button-primary:hover { background: #ba3923; color: #fff; }
.sample-button-secondary { border-color: var(--sample-navy); background: #fff; color: var(--sample-navy); }
.sample-button-secondary:hover { background: var(--sample-navy); color: #fff; }

.sample-categories-section {
    padding: 0 0 78px;
}

.sample-section-heading {
    max-width: 700px;
    margin: 0 auto 36px;
    text-align: center;
}

.sample-section-heading h2,
.sample-enrollment-cta h2 {
    margin: 0 0 12px;
    color: var(--sample-navy);
    font-size: clamp(2rem, 4vw, 3rem);
    line-height: 1.12;
    letter-spacing: -.025em;
}

.sample-section-heading p,
.sample-enrollment-cta p {
    margin: 0;
    color: var(--sample-muted);
    font-size: 1.03rem;
    line-height: 1.6;
}

.sample-problems-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
}

.sample-problem-card {
    overflow: hidden;
    border: 1px solid #dfe4ed;
    border-radius: 14px;
    background: #fff;
    box-shadow: 0 8px 24px rgba(28, 43, 75, .07);
    transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}

.sample-problem-card:hover {
    border-color: #b8c7df;
    transform: translateY(-4px);
    box-shadow: 0 16px 34px rgba(28,43,75,.14);
}

.sample-card-image {
    position: relative;
    height: 220px;
    display: block;
    overflow: hidden;
    border-bottom: 1px solid #e7ebf1;
    background: var(--sample-surface);
}

.sample-card-image img {
    width: 100%;
    height: 100%;
    display: block;
    padding: 10px;
    object-fit: cover;
    object-position: top center;
    transition: transform .25s ease;
}

.sample-problem-card:hover .sample-card-image img {
    transform: scale(1.025);
}

.sample-card-content {
    padding: 22px;
}

.sample-level {
    color: var(--sample-red);
    font-size: .72rem;
    font-weight: 800;
    letter-spacing: .08em;
    text-transform: uppercase;
}

.sample-card-content h3 {
    margin: 8px 0 10px;
    color: var(--sample-navy);
    font-size: 1.35rem;
}

.sample-card-content p {
    min-height: 5em;
    margin: 0 0 20px;
    color: var(--sample-muted);
    line-height: 1.6;
}

.sample-card-link {
    color: var(--sample-blue);
    font-weight: 800;
    text-decoration: none;
}

.sample-card-link:hover { text-decoration: underline; }

.sample-enrollment-cta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 36px;
    padding: 42px;
    border: 1px solid #dce3ef;
    border-radius: 18px;
    background: var(--sample-surface);
}

.sample-enrollment-cta > div:first-child { max-width: 700px; }
.sample-cta-actions { display: flex; flex: 0 0 auto; gap: 10px; }

@media (max-width: 900px) {
    .sample-problems-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .problem-week-card { grid-template-columns: auto 1fr; }
    .problem-week-card .sample-button { grid-column: 1 / -1; }
    .sample-enrollment-cta { align-items: flex-start; flex-direction: column; }
}

@media (max-width: 620px) {
    .sample-problems-page { width: min(100% - 28px, 1200px); padding-top: 28px; }
    .sample-problems-hero { align-items: flex-start; flex-direction: column; padding: 28px 22px; }
    .sample-hero-highlight { width: 100%; }
    .problem-week-card { grid-template-columns: 1fr; margin-bottom: 56px; padding: 26px 22px; }
    .problem-week-icon { width: 52px; height: 52px; }
    .sample-problems-grid { grid-template-columns: 1fr; }
    .sample-card-content p { min-height: 0; }
    .sample-enrollment-cta { padding: 30px 22px; }
    .sample-cta-actions { width: 100%; flex-direction: column; }
    .sample-cta-actions .sample-button { width: 100%; }
}