/* Premium Styles for Multi-Split PDF */
:root {
    --primary-color: #4f46e5;
    --primary-gradient: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
    --surface-color: #ffffff;
    --background-color: #f8fafc;
    --border-color: #e2e8f0;
}

body {
    background-color: var(--background-color);
}

.tool-header {
    background: white;
    padding: 40px 15px;
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.02);
    margin-bottom: 40px;
}

@media (max-width: 768px) {
    .tool-header h1 {
        font-size: 1.8rem !important;
    }
    .tool-header p {
        font-size: 1rem !important;
    }
}

/* Premium Upload Area */
.upload-area {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    border: 2px dashed #cbd5e1;
    border-radius: 24px;
    padding: 60px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05);
    position: relative;
    overflow: hidden;
}

@media (min-width: 768px) {
    .upload-area {
        padding: 80px 40px;
    }
}

.upload-area::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: var(--primary-gradient);
    opacity: 0;
    transition: opacity 0.4s ease;
    z-index: 0;
}

.upload-area:hover, .upload-area.dragover {
    border-color: transparent;
    transform: translateY(-5px);
    box-shadow: 0 20px 40px -5px rgba(79, 70, 229, 0.2);
}

.upload-area:hover::before, .upload-area.dragover::before {
    opacity: 0.03;
}

.upload-content {
    position: relative;
    z-index: 1;
}

.upload-icon-wrapper {
    width: 80px;
    height: 80px;
    background: #eef2ff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    box-shadow: 0 0 0 0 rgba(79, 70, 229, 0.5);
    animation: pulse 2s infinite;
}

@media (min-width: 768px) {
    .upload-icon-wrapper {
        width: 100px;
        height: 100px;
        margin: 0 auto 24px;
    }
}

@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(79, 70, 229, 0.4); }
    70% { box-shadow: 0 0 0 20px rgba(79, 70, 229, 0); }
    100% { box-shadow: 0 0 0 0 rgba(79, 70, 229, 0); }
}

.btn-premium {
    background: var(--primary-gradient);
    color: white;
    border: none;
    padding: 12px 32px;
    font-weight: 600;
    border-radius: 50px;
    box-shadow: 0 4px 15px rgba(79, 70, 229, 0.3);
    transition: all 0.3s ease;
}

.btn-premium:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(79, 70, 229, 0.4);
    color: white;
}

.btn-premium:disabled {
    background: #cbd5e1;
    box-shadow: none;
    cursor: not-allowed;
    transform: none;
}

.pages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    gap: 1.5rem;
}

.page-card {
    background: white;
    border-radius: 8px;
    padding: 8px;
    text-align: center;
    cursor: default;
    border: 2px solid transparent;
    transition: all 0.2s ease;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
    position: relative;
}

.page-card.highlighted {
    border-color: var(--primary-color);
    box-shadow: 0 4px 12px rgba(79, 70, 229, 0.2);
}

.page-card .page-canvas {
    max-width: 100%;
    height: auto;
    border: 1px solid #e2e8f0;
    border-radius: 4px;
}

.page-number {
    font-size: 12px;
    font-weight: bold;
    color: #64748b;
    margin-top: 8px;
}

/* Range Inputs */
.range-item {
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    padding: 12px;
    margin-bottom: 12px;
    position: relative;
}

.remove-range-btn {
    position: absolute;
    top: -8px;
    right: -8px;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: #ef4444;
    color: white;
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    cursor: pointer;
    box-shadow: 0 2px 4px rgba(239, 68, 68, 0.3);
}

.remove-range-btn:hover {
    background: #dc2626;
}