:root {
    --primary: #ffffff;
    --primary-hover: #e2e8f0;
    --bg-color: #000000;
    --card-bg: rgba(18, 18, 18, 0.8);
    --text-primary: #ffffff;
    --text-secondary: #9ca3af;
    --accent: #6b7280;
    --success: #10b981;
    --error: #ef4444;
    --border: rgba(255, 255, 255, 0.08);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    overflow-x: hidden;
    line-height: 1.6;
}

/* Background Blobs */
.background-blobs {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    filter: blur(80px);
}

.blob {
    position: absolute;
    width: 40vw;
    height: 40vw;
    border-radius: 50%;
    opacity: 0.2;
    animation: move 20s infinite alternate;
}

.blob-1 {
    background: #1f2937;
    top: -10%;
    left: -10%;
}

.blob-2 {
    background: #374151;
    bottom: -10%;
    right: -10%;
    animation-delay: -5s;
}

.blob-3 {
    background: #111827;
    top: 40%;
    left: 30%;
    width: 20vw;
    height: 20vw;
    animation-delay: -10s;
}

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

.container {
    max-width: 600px;
    width: 90%;
    margin: 60px auto;
    flex-grow: 1;
}

header {
    text-align: center;
    margin-bottom: 40px;
}

.logo {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -1px;
    margin-bottom: 8px;
}

.logo span {
    color: var(--accent);
}

.tagline {
    color: var(--text-secondary);
    font-weight: 300;
}

/* Upload Card */
.upload-card {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 32px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    margin-bottom: 60px;
}

.drop-zone {
    border: 2px dashed var(--border);
    border-radius: 16px;
    padding: 60px 40px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 24px;
}

.drop-zone:hover, .drop-zone.dragover {
    border-color: var(--primary);
    background: rgba(79, 70, 229, 0.05);
}

.upload-icon {
    width: 48px;
    height: 48px;
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.drop-zone p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.drop-zone span {
    color: var(--accent);
    font-weight: 600;
    text-decoration: underline;
}

/* File List Preview */
.file-list-preview {
    margin-bottom: 24px;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: rgba(255, 255, 255, 0.05);
    padding: 12px 16px;
    border-radius: 12px;
    margin-bottom: 10px;
    animation: fadeIn 0.3s ease;
}

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

.file-name {
    font-weight: 500;
    font-size: 0.95rem;
    max-width: 250px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

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

.remove-file {
    background: none;
    border: none;
    color: var(--error);
    cursor: pointer;
    padding: 4px;
    border-radius: 50%;
    transition: background 0.2s;
}

.remove-file:hover {
    background: rgba(239, 68, 68, 0.1);
}

/* Buttons */
.btn-primary {
    width: 100%;
    padding: 16px;
    border-radius: 12px;
    border: 1px solid var(--border);
    background: #1f2937;
    color: white;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-primary:hover:not(:disabled) {
    background: #374151;
    transform: translateY(-2px);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.4);
}

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Progress Bar */
.progress-container {
    margin-top: 24px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 4px;
    overflow: hidden;
}

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

#progress-text {
    font-size: 0.85rem;
    color: var(--text-secondary);
    text-align: right;
}

/* Recent Files */
.files-history h2 {
    font-size: 1.25rem;
    margin-bottom: 24px;
    font-weight: 600;
}

.files-grid {
    display: grid;
    gap: 16px;
}

.history-item {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: transform 0.2s;
}

.history-item:hover {
    transform: scale(1.02);
    border-color: var(--accent);
}

.download-link {
    background: rgba(14, 165, 233, 0.1);
    color: var(--accent);
    text-decoration: none;
    padding: 8px 16px;
    border-radius: 8px;
    font-size: 0.9rem;
    font-weight: 600;
    transition: all 0.2s;
}

.download-link:hover {
    background: var(--accent);
    color: white;
}

.empty-state {
    text-align: center;
    color: var(--text-secondary);
    padding: 40px;
    border: 1px dashed var(--border);
    border-radius: 16px;
}

/* Status Message */
.status-message {
    margin-top: 16px;
    text-align: center;
    font-size: 0.9rem;
    padding: 12px;
    border-radius: 8px;
    display: none;
}

.status-success {
    display: block;
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
}

.status-error {
    display: block;
    background: rgba(239, 68, 68, 0.1);
    color: var(--error);
}

footer {
    padding: 40px;
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
    opacity: 0.7;
}

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