:root {
    --primary: #6366f1;
    --primary-glow: rgba(99, 102, 241, 0.4);
    --success: #10b981;
    --error: #ef4444;
    --bg: #0f172a;
    --surface: rgba(30, 41, 59, 0.7);
    --border: rgba(148, 163, 184, 0.1);
    --text: #f8fafc;
    --text-muted: #94a3b8;
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.08);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg);
    color: var(--text);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.6;
}

h1, h2, h3 {
    font-family: 'Outfit', sans-serif;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 4rem 2rem;
    position: relative;
    z-index: 10;
}

/* Background Decorations */
.background-blobs {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    overflow: hidden;
    filter: blur(80px);
}

.blob {
    position: absolute;
    border-radius: 50%;
    opacity: 0.4;
    animation: move 20s infinite alternate;
}

.blob-1 {
    width: 500px;
    height: 500px;
    background: var(--primary);
    top: -100px;
    left: -100px;
}

.blob-2 {
    width: 400px;
    height: 400px;
    background: #a855f7;
    bottom: -50px;
    right: -50px;
    animation-delay: -5s;
}

.blob-3 {
    width: 300px;
    height: 300px;
    background: #ec4899;
    top: 40%;
    left: 40%;
    animation-delay: -10s;
}

@keyframes move {
    from { transform: translate(0, 0) scale(1); }
    to { transform: translate(100px, 100px) scale(1.1); }
}

/* Header */
.header {
    text-align: center;
    margin-bottom: 4rem;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1rem;
}

.logo-icon {
    width: 3rem;
    height: 3rem;
    color: var(--primary);
}

.gradient-text {
    font-size: 3.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, #fff 0%, var(--primary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.02em;
}

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

/* Upload Section */
.upload-section {
    margin-bottom: 3rem;
}

.drop-zone {
    background: var(--surface);
    border: 2px dashed var(--glass-border);
    border-radius: 2rem;
    padding: 5rem 2rem;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    position: relative;
    overflow: hidden;
}

.drop-zone:hover, .drop-zone.drag-over {
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.05);
    box-shadow: 0 0 40px var(--primary-glow);
}

.drop-zone-content {
    position: relative;
    z-index: 2;
}

.icon-stack {
    margin-bottom: 1.5rem;
}

.upload-icon {
    width: 4rem;
    height: 4rem;
    color: var(--primary);
}

.drop-zone h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.drop-zone p {
    color: var(--text-muted);
}

.formats-info {
    margin-top: 2rem;
    display: flex;
    justify-content: center;
    gap: 1rem;
    font-size: 0.85rem;
    color: var(--primary);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.separator {
    color: var(--text-muted);
    opacity: 0.5;
}

/* Process Section */
.process-section {
    background: var(--surface);
    border-radius: 2rem;
    padding: 2.5rem;
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    animation: slideUp 0.5s ease;
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.file-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
    max-height: 400px;
    overflow-y: auto;
    padding-right: 0.5rem;
}

.file-list::-webkit-scrollbar {
    width: 6px;
}

.file-list::-webkit-scrollbar-thumb {
    background: var(--glass-border);
    border-radius: 10px;
}

/* File Item */
.file-item {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 1rem;
    padding: 1rem 1.5rem;
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
    gap: 1rem;
    position: relative;
    overflow: hidden;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.file-icon {
    width: 2.5rem;
    height: 2.5rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
}

.file-details {
    display: flex;
    flex-direction: column;
}

.file-name {
    font-weight: 600;
    font-size: 0.95rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 300px;
}

.file-meta {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.file-status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.status-icon {
    width: 1.5rem;
    height: 1.5rem;
}

.status-icon.success { color: var(--success); }
.status-icon.error { color: var(--error); }

.progress-bar-container {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: rgba(255, 255, 255, 0.05);
}

.progress-bar {
    height: 100%;
    width: 0%;
    background: var(--primary);
    transition: width 0.3s ease;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: 0.75rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
    font-size: 0.95rem;
}

.btn-primary {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 15px var(--primary-glow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px var(--primary-glow);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
}

.btn-success {
    background: var(--success);
    color: white;
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

.result-actions {
    display: flex;
    justify-content: center;
    margin-top: 1rem;
    padding-top: 2rem;
    border-top: 1px solid var(--glass-border);
}

.hidden {
    display: none !important;
}

/* Spinner */
.spinner {
    width: 1.2rem;
    height: 1.2rem;
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.download-single-btn {
    background: none;
    border: none;
    color: var(--primary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 0.5rem;
}

.download-single-btn:hover {
    background: rgba(99, 102, 241, 0.1);
}

.footer {
    margin-top: 4rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

@media (max-width: 640px) {
    .gradient-text { font-size: 2.5rem; }
    .section-header { flex-direction: column; gap: 1rem; align-items: flex-start; }
    .actions { width: 100%; display: flex; gap: 0.5rem; }
    .btn { flex: 1; }
}