.indent-li li {
    text-indent: 4ch;
}

h4 {
    padding-bottom: 10px;
}

.main-title {
    font-size: 2.8rem;
    color: var(--primary-color);
    margin-bottom: 3rem;
    position: relative;
    display: inline-block;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.05);
}

.main-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 120px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.roadmap-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2.5rem;
    margin-top: 2rem;
}

.roadmap-section {
    background: white;
    border-radius: 20px;
    padding: 2rem;
    position: relative;
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    box-shadow: var(--card-shadow);
    overflow: hidden;
}

.roadmap-section:hover {
    transform: translateY(-8px);
    box-shadow: var(--hover-shadow);
}

.section-header {
    position: relative;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.section-icon {
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    font-size: 1.4rem;
    transition: transform 0.3s ease;
}

.roadmap-section:hover .section-icon {
    transform: rotate(10deg) scale(1.1);
}

.section-title {
    font-size: 1.2rem;
    color: #1e293b;
    margin: 0;
    position: relative;
    padding-left: 1rem;
}

.section-title::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 30px;
    background: linear-gradient(to bottom, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.topic-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.topic-item {
    position: relative;
    padding: 0.8rem 1rem 0.8rem 2.5rem;
    margin-bottom: 0.6rem;
    background: #f8fafc;
    border-radius: 12px;
    transition: all 0.2s ease;
    opacity: 0;
    transform: translateX(-20px);
    animation: fadeIn 0.5s forwards;
}

@keyframes fadeIn {
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.topic-item:hover {
    background: #eff6ff;
    padding-left: 3rem;
}

.topic-item::before {
    content: '\f058';
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--primary-color);
    font-size: 0.9rem;
}

/* 不同章节图标颜色 */
.section-1 .section-icon {
    background: linear-gradient(135deg, #2563eb, #1d4ed8);
}

.section-2 .section-icon {
    background: linear-gradient(135deg, #10b981, #059669);
}

.section-3 .section-icon {
    background: linear-gradient(135deg, #f59e0b, #d97706);
}

.section-4 .section-icon {
    background: linear-gradient(135deg, #ef4444, #b91c1c);
}

.section-5 .section-icon {
    background: linear-gradient(135deg, #8b5cf6, #7c3aed);
}

.section-6 .section-icon {
    background: linear-gradient(135deg, #ec4899, #be185d);
}

.section-7 .section-icon {
    background: linear-gradient(135deg, #3b82f6, #2563eb);
}

.section-8 .section-icon {
    background: linear-gradient(135deg, #fbbf24, #d4af37);
}

.section-9 .section-icon {
    background: linear-gradient(135deg, #14b8a6, #064e3b);
}

.section-10 .section-icon {
    background: linear-gradient(135deg, #84cc16, #65a30d);
}

.section-11 .section-icon {
    background: linear-gradient(135deg, #f97316, #d9480f);
}

.section-12 .section-icon {
    background: linear-gradient(135deg, #a855f7, #9333ea);
}

.section-13 .section-icon {
    background: linear-gradient(135deg, #22c55e, #16a34a);
}

.section-14 .section-icon {
    background: linear-gradient(135deg, #0ea5e9, #06b6d4);
}

.section-15 .section-icon {
    background: linear-gradient(135deg, #64748b, #475569);
}

/* 响应式调整 */
@media (max-width: 768px) {
    .roadmap-container {
        grid-template-columns: 1fr;
    }

    .main-title {
        font-size: 2rem;
    }

    .section-header {
        flex-direction: column;
        text-align: center;
    }

    .section-icon {
        margin: 0 auto 1rem;
    }

    .section-title::before {
        display: none;
    }
}