* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, sans-serif;
}

body {
    background: linear-gradient(145deg, #f6f9fc 0%, #eef2f5 100%);
    padding: 2rem 1.5rem;
    min-height: 100vh;
}

.main-container {
    max-width: 1400px;
    margin: 0 auto;
}

/* 头部 */
.header {
    text-align: center;
    margin-bottom: 2.5rem;
    position: relative;
}

.back-home-btn {
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    background: white;
    color: #2c7da0;
    padding: 10px 20px;
    border-radius: 40px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9rem;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.back-home-btn:hover {
    background: #2c7da0;
    color: white;
    transform: translateY(-50%) scale(1.05);
    box-shadow: 0 6px 16px rgba(44,125,160,0.3);
}

.header h1 {
    font-size: 2.2rem;
    font-weight: 700;
    background: linear-gradient(135deg, #1A2A3F, #2C4C6E);
    background-clip: text;
    -webkit-background-clip: text;
    color: transparent;
    letter-spacing: -0.3px;
}

.header p {
    color: #5a6e7c;
    margin-top: 8px;
    font-weight: 500;
}

/* 卡片网格 */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(380px, 1fr));
    gap: 2rem;
}

.card {
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(0px);
    border-radius: 32px;
    box-shadow: 0 20px 35px -12px rgba(0, 0, 0, 0.1), 0 1px 2px rgba(0,0,0,0.02);
    transition: transform 0.2s ease, box-shadow 0.2s;
    overflow: hidden;
    border: 1px solid rgba(255,255,255,0.5);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 28px 40px -14px rgba(0, 0, 0, 0.18);
}

.card-header {
    background: #ffffffcc;
    padding: 1.2rem 1.8rem;
    border-bottom: 2px solid #e9edf2;
}

.card-header h2 {
    font-size: 1.5rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 10px;
    color: #1e2f3e;
}

.card-header h2 i {
    font-size: 1.6rem;
    font-weight: 400;
}

.card-body {
    padding: 1.5rem;
}

/* 上传区域 */
.upload-zone {
    border: 2px dashed #bdd3e8;
    border-radius: 24px;
    padding: 1.5rem 1rem;
    text-align: center;
    background: #fafdff;
    transition: all 0.2s;
    cursor: pointer;
    margin-bottom: 1.5rem;
}

.upload-zone.drag-over {
    border-color: #2c7da0;
    background: #eef5fc;
    transform: scale(0.98);
}

.upload-icon {
    font-size: 2.2rem;
    margin-bottom: 8px;
}

.upload-zone p {
    color: #4b6f86;
    font-weight: 500;
}

.upload-sub {
    font-size: 0.75rem;
    color: #8da0ad;
    margin-top: 6px;
}

/* 文件列表 */
.file-list {
    background: #f8fafc;
    border-radius: 20px;
    padding: 0.8rem;
    margin-top: 1rem;
    max-height: 260px;
    overflow-y: auto;
    border: 1px solid #e2edf2;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: white;
    margin-bottom: 8px;
    padding: 8px 12px;
    border-radius: 18px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.05);
    transition: all 0.1s;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 1;
    overflow: hidden;
}

.thumbnail {
    width: 36px;
    height: 36px;
    background: #eef2f5;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
}

.file-name {
    font-weight: 500;
    font-size: 0.85rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 160px;
}

.file-meta {
    font-size: 0.7rem;
    color: #6f8e9f;
}

.file-actions {
    display: flex;
    gap: 6px;
}

.btn-icon {
    background: #f0f4f8;
    border: none;
    border-radius: 30px;
    width: 28px;
    height: 28px;
    font-size: 0.9rem;
    cursor: pointer;
    transition: 0.1s;
    font-weight: bold;
}

.btn-icon:hover {
    background: #e0e8f0;
    transform: scale(1.02);
}

.btn-danger {
    color: #c23d3d;
}

.btn-primary {
    background: #2c7da0;
    border: none;
    color: white;
    padding: 10px 22px;
    border-radius: 40px;
    font-weight: 600;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s;
    width: 100%;
    margin-top: 1rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.btn-primary:hover {
    background: #1f5e7a;
    transform: scale(0.98);
}

.btn-secondary {
    background: #eef2f5;
    color: #2c5a6e;
    border: 1px solid #cbdde6;
    padding: 8px 16px;
    border-radius: 40px;
    font-weight: 500;
    cursor: pointer;
    transition: 0.1s;
}

.split-options {
    background: #f1f6f9;
    border-radius: 20px;
    padding: 1rem;
    margin: 1rem 0;
}

.split-option-item {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
    flex-wrap: wrap;
}

.split-option-item label {
    font-weight: 600;
    color: #1f5068;
}

input, select {
    padding: 8px 12px;
    border-radius: 40px;
    border: 1px solid #cbdde6;
    background: white;
    font-size: 0.85rem;
}

.range-input {
    flex: 2;
    min-width: 180px;
}

.info-badge {
    background: #e2eaf1;
    padding: 6px 12px;
    border-radius: 30px;
    font-size: 0.75rem;
    font-weight: 500;
    color: #1f5a78;
}

.loading-toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%);
    background: #1e2f3e;
    color: white;
    padding: 10px 24px;
    border-radius: 60px;
    font-weight: 500;
    font-size: 0.85rem;
    z-index: 1000;
    box-shadow: 0 10px 20px rgba(0,0,0,0.2);
    opacity: 0;
    transition: 0.2s;
    pointer-events: none;
}
.loading-toast.show {
    opacity: 1;
}
hr {
    margin: 12px 0;
    border-color: #e2edf2;
}
.flex-between {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.empty-list {
    text-align: center;
    color: #94abb9;
    padding: 20px;
    font-size: 0.8rem;
}
button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}
/* 响应式设计 */
@media (max-width: 768px) {
    .header {
        padding-top: 50px;
    }
    
    .back-home-btn {
        position: static;
        transform: none;
        margin-bottom: 1rem;
    }
    
    .back-home-btn:hover {
        transform: scale(1.05);
    }
}

::-webkit-scrollbar {
    width: 5px;
}