.ss-study-shell {
    display: grid;
    grid-template-columns: 210px minmax(0, 1fr);
    gap: 16px;
    min-height: calc(100vh - 78px);
    padding: 16px;
    background: radial-gradient(circle at top left, rgba(37, 99, 235, .07), transparent 32%), #f6f8fc;
}

.ss-study-side-nav {
    position: sticky;
    top: 90px;
    align-self: start;
    display: grid;
    align-content: start;
    gap: 7px;
    min-width: 0;
}

.ss-study-side-link {
    display: flex;
    align-items: center;
    gap: 10px;
    min-height: 42px;
    padding: 7px 10px;
    border: 1px solid transparent;
    border-radius: 13px;
    background: rgba(255, 255, 255, .76);
    color: #475467;
    text-decoration: none;
    font-weight: 760;
    letter-spacing: -.01em;
    transition: background-color .16s ease, border-color .16s ease, color .16s ease, transform .16s ease;
}

.ss-study-side-link strong {
    min-width: 0;
    overflow: hidden;
    color: inherit;
    font-size: 13px;
    line-height: 1.2;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.ss-study-side-icon {
    display: grid;
    place-items: center;
    width: 28px;
    height: 28px;
    flex: 0 0 28px;
    overflow: hidden;
    border-radius: 10px;
    background: #eef4ff;
    color: #2563eb;
}

.ss-study-side-icon img {
    width: 20px;
    height: 20px;
    object-fit: contain;
}

.ss-study-side-fallback {
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 10px;
    font-weight: 900;
}

.ss-study-side-link:hover,
.ss-study-side-link:focus-visible,
.ss-study-side-link.active,
.ss-study-side-link[aria-current="page"] {
    border-color: #d7e4ff;
    background: linear-gradient(135deg, rgba(37, 99, 235, .1), rgba(20, 184, 166, .06));
    color: #1d4ed8;
    outline: 0;
}

.ss-study-side-link:hover,
.ss-study-side-link:focus-visible { transform: translateX(2px); }
.ss-study-side-link:focus-visible { box-shadow: 0 0 0 4px rgba(37, 99, 235, .12); }
.ss-study-content { min-width: 0; }

.ss-study-side-art {
    position: relative;
    overflow: hidden;
    min-height: 260px;
    margin-top: 8px;
    border: 1px solid rgba(215, 228, 255, .75);
    border-radius: 18px;
    background: linear-gradient(180deg, #f8fbff, #eef6ff);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, .72);
}

.ss-study-side-art img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: left bottom;
    opacity: .96;
}

.ss-study-side-art::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, rgba(255, 255, 255, .18), rgba(255, 255, 255, .04));
    pointer-events: none;
}

.ss-study-side-art-fallback::before {
    content: "";
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 35% 30%, rgba(37, 99, 235, .14), transparent 38%), linear-gradient(180deg, #eef6ff, #fff);
}

@media (max-width: 991.98px) {
    .ss-study-shell { grid-template-columns: 1fr; padding: 10px; }
    .ss-study-side-nav { position: static; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 8px; }
    .ss-study-side-link { justify-content: center; min-height: 46px; padding: 8px; }
    .ss-study-side-link strong { display: none; }
    .ss-study-side-icon { width: 30px; height: 30px; flex-basis: 30px; }
    .ss-study-side-icon img { width: 21px; height: 21px; }
    .ss-study-side-art { display: none; }
}

@media (max-width: 575.98px) {
    .ss-study-side-nav { grid-template-columns: repeat(5, minmax(0, 1fr)); }
}