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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: linear-gradient(180deg, #d9f2e8 0%, #f3faf7 40%, #f7fbff 100%);
}

.app {
    max-width: 430px;
    min-height: 100vh;
    margin: 0 auto;
    background: #ffffff;
    display: flex;
    flex-direction: column;
    border-radius: 16px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    overflow: hidden;
}

.app-main {
    flex: 1;
    padding: 16px;
    overflow-y: auto;
    background: linear-gradient(180deg, #f9fffc 0%, #f7fbff 100%);
}

.category-bar {
    display: flex;
    gap: 8px;
    margin-bottom: 12px;
    flex-wrap: wrap;
}

.category-btn {
    padding: 6px 12px;
    border-radius: 16px;
    border: 1px solid #b2e0cc;
    background: rgba(255, 255, 255, 0.9);
    font-size: 13px;
    color: #339966;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.04);
}

.category-btn.active {
    background: #339966;
    color: #ffffff;
}

.content-list {
    font-size: 14px;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 10px;
}

.content-item {
    background: #ffffff;
    border-radius: 10px;
    border: 1px solid #e6f0f5;
    padding: 8px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.06);
}

.content-item-img {
    width: 100%;
    border-radius: 6px;
    margin-bottom: 6px;
    display: block;
}

.content-item-title {
    font-size: 13px;
    color: #333;
    line-height: 1.3;
    min-height: 32px;
}

.content-item-desc {
    margin-top: 4px;
    font-size: 12px;
    color: #f40;
}

.app-tabbar {
    height: 56px;
    border-top: 1px solid #b2e0cc;
    display: flex;
    background: #f0fff7;
}

.tab-item {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    color: #339966;
    text-decoration: none;
}

.tab-item.active,
.tab-item:active {
    color: #007bff;
}

@media (max-width: 600px) {
    body {
        background: #f5f7fa;
    }

    .app {
        max-width: 100%;
        border-radius: 0;
        box-shadow: none;
    }

    .app-main {
        padding: 12px;
    }

    .content-list {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 8px;
    }

    .app-tabbar {
        height: 50px;
        padding-bottom: env(safe-area-inset-bottom);
    }

    .tab-item {
        font-size: 13px;
    }
}

@media (min-width: 768px) {
    .app {
        max-width: 600px;
    }
}