/* Loading Animation */
.loading-spinner {
    display: none;
    width: 50px;
    height: 50px;
    border: 5px solid #f3f3f3;
    border-top: 5px solid #3B82F6;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* File Upload Progress */
.progress-bar {
    width: 100%;
    height: 6px;
    background-color: #e5e7eb;
    border-radius: 3px;
    overflow: hidden;
    display: none;
    margin: 1rem auto;
    max-width: 300px;
}

.progress-bar-fill {
    height: 100%;
    background-color: #3B82F6;
    width: 0%;
    transition: width 0.3s ease;
}

/* Tooltip */
.tooltip {
    position: relative;
    display: inline-block;
}

.tooltip .tooltip-text {
    visibility: hidden;
    background-color: #1f2937;
    color: white;
    text-align: center;
    padding: 8px 12px;
    border-radius: 6px;
    position: absolute;
    z-index: 1;
    bottom: 125%;
    left: 50%;
    transform: translateX(-50%);
    opacity: 0;
    transition: opacity 0.3s;
    font-size: 0.875rem;
    white-space: nowrap;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.tooltip:hover .tooltip-text {
    visibility: visible;
    opacity: 1;
}

/* File Type Icons */
.file-type-icon {
    font-size: 1.5rem;
    margin-right: 0.5rem;
    color: #3B82F6;
}

/* Success Animation */
@keyframes checkmark {
    0% { transform: scale(0); opacity: 0; }
    50% { transform: scale(1.2); opacity: 0.8; }
    100% { transform: scale(1); opacity: 1; }
}

.success-checkmark {
    display: none;
    color: #10B981;
    animation: checkmark 0.5s ease-in-out forwards;
}

/* Sample Data Cards */
.sample-btn {
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.sample-btn::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(rgba(255,255,255,0.1), rgba(255,255,255,0));
    transform: translateY(-100%);
    transition: transform 0.3s ease;
}

.sample-btn:hover::after {
    transform: translateY(0);
}

.sample-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 15px rgba(0,0,0,0.1);
}

/* Drop Zone Enhancements */
.drop-zone {
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.drop-zone::before {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border-radius: 8px;
    border: 2px dashed #3B82F6;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.drop-zone:hover::before {
    opacity: 1;
}

/* File Info Card */
#fileInfo {
    background: linear-gradient(to right, #f8fafc, #f1f5f9);
    border: 1px solid #e2e8f0;
    transition: all 0.3s ease;
}

#fileInfo:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

/* Features Section */
.feature-card {
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 15px rgba(0,0,0,0.1);
}

.feature-icon {
    transition: all 0.3s ease;
}

.feature-card:hover .feature-icon {
    transform: scale(1.1);
    color: #2563eb;
}

@media only screen and (max-width: 600px) {
    .feature-card p {grid-column: 1/3;}
    .feature-card i, .feature-card h3 {text-align: center;}
    .feature-card {
        display: grid;
        grid-template-columns: 1fr 2fr;
        align-items: baseline;
    }
  }