:root {
    --bg-color: #121212;
    --primary-color: #1e1e1e;
    --secondary-color: #2a2a2a;
    --font-color: #e0e0e0;
    --accent-color: #03dac6;
    --border-color: #333;
}
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--font-color);
    margin: 0;
    padding: 1rem;
}
.container { max-width: 900px; margin: 0 auto; }
h1 { text-align: center; margin-bottom: 2rem; }
.card { background-color: var(--primary-color); border: 1px solid var(--border-color); border-radius: 8px; padding: 1.5rem; margin-bottom: 1rem; }

.toolbar { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 1rem; }
.search-container { flex-grow: 1; }
#searchInput { width: 100%; max-width: 300px; background-color: var(--secondary-color); border: 1px solid var(--border-color); color: var(--font-color); padding: 0.5rem; border-radius: 4px; }
.actions button { background-color: var(--accent-color); color: #000; border: none; padding: 0.6rem 1rem; border-radius: 4px; font-weight: bold; cursor: pointer; transition: background-color 0.3s; }
.actions button:hover { background-color: #018786; }
.actions button:disabled { background-color: #555; cursor: not-allowed; }

#breadcrumbs { margin-bottom: 1rem; color: #aaa; word-break: break-all; }
#breadcrumbs a { color: var(--accent-color); text-decoration: none; }
#breadcrumbs a:hover { text-decoration: underline; }

#fileList { list-style: none; padding: 0; }
.file-item { display: flex; align-items: center; padding: 0.75rem; border-radius: 4px; transition: background-color 0.2s; }
.file-item:not(:last-child) { border-bottom: 1px solid var(--border-color); }
.file-item:hover { background-color: var(--secondary-color); }
.file-item input[type="checkbox"] { margin-right: 1rem; }
.file-item .icon { margin-right: 1rem; width: 24px; }
.file-item .name { flex-grow: 1; overflow-wrap: break-word; }
.file-item .size { margin-left: 1rem; color: #aaa; white-space: nowrap; }
.file-item .download-btn {
    margin-left: 1rem;
    padding: 0.3rem 0.8rem;
    background-color: var(--secondary-color);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    text-decoration: none;
    font-size: 0.9rem;
    color: var(--font-color);
    transition: background-color 0.2s, color 0.2s;
    white-space: nowrap;
}
.file-item .download-btn:hover { background-color: var(--accent-color); color: #000; }

.upload-progress { margin-bottom: 1rem; width: 100%; background-color: var(--secondary-color); border-radius: 4px; overflow: hidden; position: relative; height: 24px; }
.progress-bar { width: 0%; height: 100%; background-color: var(--accent-color); transition: width 0.1s linear; }
.progress-text { position: absolute; top: 0; left: 0; width: 100%; height: 100%; display: flex; align-items: center; justify-content: center; color: #000; font-weight: bold; font-size: 0.8rem; }

/* --- NEW: Responsive Styles --- */
@media (max-width: 768px) {
    body { padding: 0.5rem; }
    h1 { font-size: 1.5rem; }
    .card { padding: 1rem; }
    .toolbar { flex-direction: column; align-items: stretch; }
    .search-container { margin-bottom: 1rem; }
    #searchInput { max-width: none; }
    .actions { display: flex; justify-content: space-around; gap: 0.5rem; }
    .actions button { padding: 0.5rem; font-size: 0.8rem; flex-grow: 1; }

    .file-item { padding: 0.5rem; }
    .file-item .name { font-size: 0.9rem; }
    .file-item .size { font-size: 0.8rem; }
    .file-item .download-btn { padding: 0.2rem 0.5rem; font-size: 0.8rem; }
}