.materials-hero {
    padding: 60px 0 40px;
    background: linear-gradient(135deg, rgba(11, 42, 58, 0.85) 0%, rgba(13, 61, 79, 0.85) 100%);
    border-bottom: 1px solid rgba(0, 200, 210, 0.1);
    position: relative;
    z-index: 1;
    backdrop-filter: blur(5px);
}

.materials-hero-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 40px;
}

.materials-hero-text {
    flex: 1;
}

.materials-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(0, 200, 210, 0.15);
    color: #00c8d2;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 16px;
}

.materials-hero-text h1 {
    font-size: 42px;
    font-weight: 800;
    color: #fff;
    margin-bottom: 12px;
}

.materials-hero-text h1 span {
    color: #00c8d2;
}

.materials-hero-text p {
    font-size: 18px;
    color: rgba(255, 255, 255, 0.6);
    max-width: 500px;
}

.materials-hero-icon {
    font-size: 80px;
    color: rgba(0, 200, 210, 0.2);
}

.materials-hero-icon i {
    color: #00c8d2;
    opacity: 0.3;
}

.materials-hero-icon img {
    width: 100px;
    height: 100px;
    object-fit: contain;
    filter: brightness(0) saturate(100%) invert(62%) sepia(100%) saturate(400%) hue-rotate(150deg);
}

.materials-section {
    padding: 40px 0 60px;
    position: relative;
    z-index: 1;
}

.materials-filters {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
    margin-bottom: 32px;
    padding: 16px 20px;
    background: rgba(255, 255, 255, 0.06);
    backdrop-filter: blur(10px);
    border-radius: 12px;
    border: 1px solid rgba(0, 200, 210, 0.08);
}

.filters-left {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 8px 20px;
    border: 2px solid rgba(0, 200, 210, 0.15);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.04);
    color: rgba(255, 255, 255, 0.6);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
}

.filter-btn:hover {
    border-color: #00c8d2;
    color: #b0f0f5;
}

.filter-btn.active {
    background: #00c8d2;
    border-color: #00c8d2;
    color: #fff;
}

.materials-count {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.4);
    font-weight: 500;
}

.materials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 24px;
}

.material-card {
    background: rgba(255, 255, 255, 0.06);
    backdrop-filter: blur(10px);
    border-radius: 14px;
    padding: 24px;
    border: 1px solid rgba(0, 200, 210, 0.08);
    transition: all 0.3s;
    display: flex;
    flex-direction: column;
}

.material-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
    border-color: rgba(0, 200, 210, 0.3);
    background: rgba(255, 255, 255, 0.09);
}

.material-card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 12px;
}

.material-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: rgba(0, 200, 210, 0.08);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: #00c8d2;
}

.material-badge {
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.material-badge.theory {
    background: rgba(0, 200, 210, 0.12);
    color: #00c8d2;
}

.material-badge.practice {
    background: rgba(107, 203, 119, 0.12);
    color: #6bcb77;
}

.material-badge.homework {
    background: rgba(255, 107, 107, 0.12);
    color: #ff6b6b;
}

.material-card-body {
    flex: 1;
    margin-bottom: 16px;
}

.material-card-body h3 {
    font-size: 18px;
    font-weight: 700;
    color: #b0f0f5;
    margin-bottom: 6px;
}

.material-card-body p {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.5);
    line-height: 1.5;
    white-space: pre-line;
}

.material-card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 16px;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
}

.material-meta {
    display: flex;
    gap: 16px;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.3);
}

.material-meta i {
    margin-right: 4px;
}

.btn-download {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    background: #00c8d2;
    color: #fff;
    border-radius: 8px;
    text-decoration: none;
    font-size: 13px;
    font-weight: 600;
    transition: all 0.3s;
}

.btn-download:hover {
    background: #00b0b9;
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(0, 200, 210, 0.3);
}

.materials-empty {
    text-align: center;
    padding: 60px 20px;
    background: rgba(255, 255, 255, 0.04);
    backdrop-filter: blur(5px);
    border-radius: 14px;
    border: 2px dashed rgba(0, 200, 210, 0.15);
}

.materials-empty i {
    font-size: 48px;
    color: rgba(255, 255, 255, 0.2);
    margin-bottom: 16px;
}

.materials-empty h3 {
    font-size: 20px;
    color: #b0f0f5;
    margin-bottom: 8px;
}

.materials-empty p {
    color: rgba(255, 255, 255, 0.4);
}

.material-icon-wrapper {
    display: flex;
    align-items: center;
    gap: 10px;
}

.material-number {
    font-size: 16px;
    font-weight: 700;
    color: #00c8d2;
}

@media (max-width: 768px) {
    .materials-hero-content {
        flex-direction: column;
        text-align: center;
    }

    .materials-hero-text p {
        max-width: 100%;
    }

    .materials-hero-text h1 {
        font-size: 30px;
    }

    .materials-hero-icon {
        font-size: 50px;
    }

    .materials-filters {
        flex-direction: column;
        align-items: stretch;
    }

    .filters-left {
        justify-content: center;
    }

    .materials-grid {
        grid-template-columns: 1fr;
    }

    .material-card-footer {
        flex-direction: column;
        gap: 12px;
        align-items: stretch;
    }

    .btn-download {
        justify-content: center;
    }
}