.stat-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin-bottom: 18px;
}
.stat-card {
    background: #fff;
    border-radius: 14px;
    border: 1px solid #e9ecef;
    padding: 16px 12px;
    text-align: center;
    transition: all 0.2s;
    box-shadow: 0 1px 3px rgba(0,0,0,0.03);
}
.stat-card:hover {
    box-shadow: 0 4px 12px rgba(37,99,235,0.08);
    transform: translateY(-1px);
}
.stat-card .stat-icon {
    font-size: 1.2rem;
    margin-bottom: 4px;
}
.stat-card .stat-number {
    font-size: 1.4rem;
    font-weight: 800;
    color: #1e293b;
    line-height: 1.2;
}
.stat-card .stat-label {
    font-size: 0.7rem;
    color: #94a3b8;
    margin-top: 2px;
    font-weight: 500;
}
.stat-card:nth-child(1) .stat-number { color: #2563eb; }
.stat-card:nth-child(2) .stat-number { color: #16a34a; }
.stat-card:nth-child(3) .stat-number { color: #0891b2; }

.stat-btn {
    padding: 6px 16px;
    border: 1.5px solid #e2e8f0;
    border-radius: 8px;
    background: #fff;
    color: #64748b;
    font-size: 0.8rem;
    cursor: pointer;
    transition: all 0.2s;
}

.stat-btn:hover {
    border-color: #dc2626;
    color: #dc2626;
}

.learned-card {
    background: #fff;
    border-radius: 14px;
    border: 1px solid #e9ecef;
    overflow: hidden;
    margin-bottom: 10px;
    position: relative;
    transition: all 0.25s;
}
.learned-card::after {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: #16a34a;
    border-radius: 0 2px 2px 0;
}
.learned-card:hover {
    box-shadow: 0 4px 16px rgba(22,163,74,0.1);
    border-color: #bbf7d0;
}

.learned-link {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 18px;
    text-decoration: none;
    color: #334155;
}

.learned-link:hover {
    background: #f8fafc;
}

.learned-icon {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: #dcfce7;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    flex-shrink: 0;
    color: #16a34a;
    transition: all 0.2s;
}
.learned-card:hover .learned-icon {
    transform: scale(1.05);
}

.learned-info {
    flex: 1;
    min-width: 0;
}

.learned-title {
    font-size: 0.9rem;
    font-weight: 500;
    color: #1e293b;
    margin-bottom: 2px;
}

.learned-meta {
    font-size: 0.78rem;
    color: #64748b;
}

.learned-arrow {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: #f0fdf4;
    color: #86efac;
    font-size: 0.85rem;
    flex-shrink: 0;
    transition: all 0.2s;
}
.learned-link:hover .learned-arrow {
    background: #16a34a;
    color: #fff;
}

.section-title-learned {
    font-size: 0.95rem;
    font-weight: 600;
    color: #1e293b;
    margin: 16px 0 12px 0;
    padding-bottom: 8px;
    border-bottom: 2px solid #eff6ff;
    position: relative;
}
.section-title-learned::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 40px;
    height: 2px;
    background: #2563eb;
    border-radius: 1px;
}

.empty-state-page {
    text-align: center;
    padding: 60px 0;
    color: #94a3b8;
}

.empty-state-page .empty-icon {
    font-size: 3rem;
    margin-bottom: 12px;
}

.empty-state-page h3 {
    margin: 0 0 6px 0;
    color: #1e293b;
}

/* 学习页 CTA 按钮 */
.learned-cta-btn {
    display: inline-block;
    margin-top: 16px;
    padding: 10px 24px;
    background: #2563eb;
    color: #fff;
    border-radius: 10px;
    text-decoration: none;
    font-size: 0.9rem;
}

/* 学习页空状态描述文字 */
.empty-state-page .empty-desc {
    font-size: 0.92rem;
    margin: 4px 0 0;
    color: #94a3b8;
}

/* 学习页工具栏 */
.learned-toolbar {
    margin-top: 8px;
    text-align: right;
}

@media (max-width: 640px) {
    .page-header-inner { padding: 24px 0 20px; }
    .page-header h1 { font-size: 1.4rem; }
}