/* 텍스트 탐구 활동 공통 햄버거 내비게이션 */
.activity-menu {
    position: fixed;
    top: 16px;
    left: 16px;
    z-index: 9000;
    color: #0f172a;
    font-family: "Pretendard", "Noto Sans KR", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.activity-menu,
.activity-menu * {
    box-sizing: border-box;
}

.activity-menu summary {
    list-style: none;
}

.activity-menu summary::-webkit-details-marker {
    display: none;
}

.activity-menu-toggle {
    width: 48px;
    height: 48px;
    display: grid;
    place-items: center;
    border: 1px solid rgba(14, 116, 144, 0.28);
    border-radius: 15px;
    background: rgba(255, 255, 255, 0.96);
    box-shadow: 0 10px 28px rgba(8, 47, 73, 0.2);
    cursor: pointer;
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    transition: border-color 0.18s ease, background-color 0.18s ease, transform 0.18s ease;
}

.activity-menu-toggle:hover {
    border-color: rgba(8, 145, 178, 0.58);
    background: #ecfeff;
    transform: translateY(-1px);
}

.activity-menu-toggle:focus-visible {
    outline: 3px solid rgba(255, 255, 255, 0.96);
    outline-offset: 3px;
}

.activity-menu-lines {
    width: 21px;
    height: 16px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.activity-menu-lines i {
    width: 100%;
    height: 2px;
    display: block;
    border-radius: 999px;
    background: #0e7490;
    transform-origin: center;
    transition: transform 0.18s ease, opacity 0.18s ease;
}

.activity-menu[open] .activity-menu-toggle {
    border-color: rgba(8, 145, 178, 0.58);
    background: #ecfeff;
}

.activity-menu[open] .activity-menu-lines i:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.activity-menu[open] .activity-menu-lines i:nth-child(2) {
    opacity: 0;
}

.activity-menu[open] .activity-menu-lines i:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

.activity-menu-panel {
    position: absolute;
    top: 58px;
    left: 0;
    width: min(320px, calc(100vw - 32px));
    max-height: calc(100vh - 90px);
    overflow-y: auto;
    padding: 12px;
    border: 1px solid rgba(14, 116, 144, 0.22);
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.985);
    box-shadow: 0 24px 60px rgba(8, 47, 73, 0.28);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    animation: activity-menu-enter 0.18s ease-out;
}

@keyframes activity-menu-enter {
    from {
        opacity: 0;
        transform: translateY(-8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.activity-menu-heading {
    padding: 6px 8px 12px;
    border-bottom: 1px solid #dbeafe;
}

.activity-menu-heading strong,
.activity-menu-heading small {
    display: block;
}

.activity-menu-heading strong {
    color: #164e63;
    font-size: 1rem;
    font-weight: 800;
}

.activity-menu-heading small {
    margin-top: 3px;
    color: #64748b;
    font-size: 0.76rem;
}

.activity-menu-links {
    display: grid;
    gap: 4px;
    padding-top: 8px;
}

.activity-menu-links a {
    min-height: 42px;
    padding: 7px 9px;
    display: flex;
    align-items: center;
    gap: 10px;
    border: 1px solid transparent;
    border-radius: 12px;
    color: #1e293b;
    background: transparent;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 700;
    line-height: 1.35;
    transition: border-color 0.15s ease, background-color 0.15s ease, color 0.15s ease;
}

.activity-menu-links a:hover {
    border-color: #bae6fd;
    background: #f0fdfa;
    color: #0e7490;
}

.activity-menu-links a:focus-visible {
    outline: 2px solid #0891b2;
    outline-offset: -2px;
}

.activity-menu-links .is-current {
    border-color: #67e8f9;
    background: #cffafe;
    color: #155e75;
}

.activity-menu-links .activity-menu-home {
    color: #64748b;
    font-size: 0.84rem;
}

.activity-menu-index {
    width: 28px;
    height: 28px;
    flex: 0 0 28px;
    display: grid;
    place-items: center;
    border-radius: 9px;
    background: #e0f2fe;
    color: #0369a1;
    font-size: 0.78rem;
    font-weight: 850;
}

.activity-menu-links .is-current .activity-menu-index {
    background: #0891b2;
    color: #fff;
}

.activity-menu-sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

@media (prefers-reduced-motion: reduce) {
    .activity-menu-panel,
    .activity-menu-toggle,
    .activity-menu-lines i {
        animation: none;
        transition: none;
    }
}

@media (max-width: 640px) {
    .activity-menu {
        top: 12px;
        left: 12px;
    }

    .activity-menu-toggle {
        width: 44px;
        height: 44px;
        border-radius: 13px;
    }

    .activity-menu-panel {
        top: 54px;
        width: min(304px, calc(100vw - 24px));
        max-height: calc(100vh - 78px);
    }
}