@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --secondary: #ec4899;
    --success: #10b981;
    --warning: #f59e0b;
    --error: #ef4444;
    --dark: #0f172a;
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --glass-bg: rgba(255, 255, 255, 0.9);
    --glass-border: rgba(255, 255, 255, 0.2);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 50%, var(--primary-dark) 100%);
    min-height: 100vh;
    padding: 2rem;
    position: relative;
    overflow-x: hidden;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(circle at 20% 50%, rgba(120, 119, 198, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255, 119, 198, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 40% 80%, rgba(120, 219, 255, 0.3) 0%, transparent 50%);
    z-index: -1;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(1deg); }
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    background: var(--glass-bg);
    border-radius: 24px;
    box-shadow: 
        0 32px 64px rgba(0, 0, 0, 0.12),
        0 0 0 1px var(--glass-border);
    padding: 3rem;
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    animation: slideUp 0.8s ease-out;
    position: relative;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.header {
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
}

.logo {
    width: 80px;
    height: 80px;
    margin: 0 auto 1rem;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    color: white;
    animation: pulse 2s ease-in-out infinite;
    box-shadow: 0 8px 32px rgba(99, 102, 241, 0.3);
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

h1 {
    font-size: 3rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.subtitle {
    color: var(--gray-600);
    font-size: 1.2rem;
    font-weight: 400;
}

.upload-section {
    margin-bottom: 2rem;
}

.upload-area {
    border: 2px dashed var(--gray-300);
    border-radius: 20px;
    padding: 3rem;
    text-align: center;
    background: var(--gray-50);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.upload-area::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(99, 102, 241, 0.1), transparent);
    transition: left 0.6s;
}

.upload-area:hover {
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.05);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(99, 102, 241, 0.15);
}

.upload-area:hover::before {
    left: 100%;
}

.upload-area.dragover {
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.1);
    transform: scale(1.02);
    box-shadow: 0 16px 50px rgba(99, 102, 241, 0.25);
}

.upload-icon {
    font-size: 4rem;
    margin-bottom: 1.5rem;
    display: block;
    color: var(--primary);
    animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.upload-text {
    font-size: 1.3rem;
    color: var(--gray-700);
    margin-bottom: 1.5rem;
    font-weight: 500;
}

.upload-subtext {
    color: var(--gray-600);
    font-size: 0.95rem;
    margin-bottom: 2rem;
}

input[type="file"] {
    display: none;
}

.btn {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    padding: 1rem 2rem;
    border: none;
    border-radius: 12px;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: 600;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.3);
    position: relative;
    overflow: hidden;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.btn i {
    font-size: 1rem;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.4);
}

.btn:hover::before {
    left: 100%;
}

.btn:active {
    transform: translateY(0);
}

.btn-secondary {
    background: linear-gradient(135deg, var(--gray-600), var(--gray-700));
    box-shadow: 0 4px 20px rgba(71, 85, 105, 0.3);
}

.btn-secondary:hover {
    box-shadow: 0 8px 30px rgba(71, 85, 105, 0.4);
}

.btn-success {
    background: linear-gradient(135deg, var(--success), #059669);
    box-shadow: 0 4px 20px rgba(16, 185, 129, 0.3);
}

.btn-success:hover {
    box-shadow: 0 8px 30px rgba(16, 185, 129, 0.4);
}

.btn:disabled {
    background: var(--gray-300);
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
    opacity: 0.6;
}

.controls {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin: 2rem 0;
    flex-wrap: wrap;
}

.file-list {
    margin: 2rem 0;
    padding: 2rem;
    background: rgba(248, 250, 252, 0.8);
    border-radius: 16px;
    border: 1px solid var(--gray-200);
    display: none;
    animation: fadeIn 0.5s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.file-list h3 {
    color: var(--gray-700);
    margin-bottom: 1.5rem;
    font-size: 1.3rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    margin: 0.75rem 0;
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    transition: all 0.3s ease;
    border: 1px solid var(--gray-100);
}

.file-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
}

.file-name {
    font-weight: 500;
    color: var(--gray-700);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.file-name i {
    color: var(--primary);
}

.file-size {
    color: var(--gray-600);
    font-size: 0.9rem;
}

.progress {
    display: none;
    margin: 2rem 0;
    text-align: center;
    animation: fadeIn 0.5s ease-out;
}

.progress-text {
    color: var(--gray-700);
    font-size: 1.2rem;
    margin-bottom: 1rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.progress-bar {
    width: 100%;
    height: 12px;
    background: var(--gray-200);
    border-radius: 6px;
    overflow: hidden;
    margin: 1rem 0;
    position: relative;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    width: 0%;
    transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
}

.progress-fill::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

.progress-percent {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary);
    margin-top: 0.5rem;
}

.status {
    margin: 2rem 0;
    padding: 2rem;
    border-radius: 16px;
    display: none;
    animation: slideIn 0.5s ease-out;
}

@keyframes slideIn {
    from { opacity: 0; transform: translateX(-20px); }
    to { opacity: 1; transform: translateX(0); }
}

.status.success {
    background: rgba(16, 185, 129, 0.1);
    color: #065f46;
    border: 2px solid rgba(16, 185, 129, 0.2);
}

.status.error {
    background: rgba(239, 68, 68, 0.1);
    color: #991b1b;
    border: 2px solid rgba(239, 68, 68, 0.2);
}

.status h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.status p {
    margin: 0.5rem 0;
    font-size: 1.1rem;
}

.status small {
    font-size: 0.9rem;
    opacity: 0.8;
}

.download-btn {
    background: linear-gradient(135deg, var(--warning), #d97706);
    color: white;
    padding: 1rem 2rem;
    border: none;
    border-radius: 12px;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: 600;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 4px 20px rgba(245, 158, 11, 0.3);
    margin-top: 1.5rem;
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(245, 158, 11, 0.4);
    text-decoration: none;
    color: white;
}

.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin: 1rem 0;
}

.stat-card {
    background: rgba(255, 255, 255, 0.7);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--gray-200);
    text-align: center;
    backdrop-filter: blur(10px);
}

.stat-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.stat-label {
    color: var(--gray-600);
    font-size: 0.9rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

@media (max-width: 768px) {
    body {
        padding: 1rem;
    }
    
    .container {
        padding: 2rem;
    }
    
    h1 {
        font-size: 2.5rem;
    }
    
    .upload-area {
        padding: 2rem;
    }
    
    .controls {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 300px;
    }
}