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

:root {
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --danger: #ef4444;
    --danger-hover: #dc2626;
    --success: #22c55e;
    --warning: #f59e0b;
    --bg: #f8fafc;
    --card-bg: #ffffff;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.5;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.card {
    background: var(--card-bg);
    border-radius: 0.75rem;
    box-shadow: var(--shadow);
    padding: 1.5rem;
    margin-bottom: 1rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 0.5rem;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.15s ease;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
}

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

.btn-danger:hover {
    background: var(--danger-hover);
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text);
}

.btn-outline:hover {
    background: var(--bg);
}

.btn-sm {
    padding: 0.25rem 0.5rem;
    font-size: 0.75rem;
}

.input {
    width: 100%;
    padding: 0.625rem 0.875rem;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    font-size: 0.875rem;
    transition: border-color 0.15s ease;
}

.input:focus {
    outline: none;
    border-color: var(--primary);
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.375rem;
    font-size: 0.875rem;
    font-weight: 500;
}

.header {
    background: var(--card-bg);
    border-bottom: 1px solid var(--border);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
}

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

.nav-link {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    padding: 0.5rem;
    border-radius: 0.375rem;
    transition: color 0.15s ease;
}

.nav-link:hover, .nav-link.active {
    color: var(--primary);
}

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

.quota-bar {
    width: 120px;
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
}

.quota-fill {
    height: 100%;
    background: var(--primary);
    transition: width 0.3s ease;
}

.quota-fill.warning {
    background: var(--warning);
}

.quota-fill.danger {
    background: var(--danger);
}

.main {
    padding: 2rem 0;
}

.auth-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.auth-card {
    width: 100%;
    max-width: 400px;
}

.auth-title {
    font-size: 1.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1.5rem;
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1rem;
    font-size: 0.875rem;
}

.breadcrumb-item {
    color: var(--text-muted);
    cursor: pointer;
}

.breadcrumb-item:hover {
    color: var(--primary);
}

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

.file-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.file-item {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    transition: border-color 0.15s ease;
}

.file-item:hover {
    border-color: var(--primary);
}

.file-icon {
    width: 2.5rem;
    height: 2.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg);
    border-radius: 0.5rem;
    margin-right: 1rem;
    font-size: 1.25rem;
}

.file-icon.folder {
    color: var(--warning);
}

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

.file-info {
    flex: 1;
    min-width: 0;
}

.file-name {
    font-weight: 500;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.file-meta {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.file-actions {
    display: flex;
    gap: 0.5rem;
}

.toolbar {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.upload-zone {
    border: 2px dashed var(--border);
    border-radius: 0.75rem;
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.15s ease;
}

.upload-zone:hover, .upload-zone.dragover {
    border-color: var(--primary);
    background: rgba(59, 130, 246, 0.05);
}

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

.upload-zone-text strong {
    color: var(--primary);
}

.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 1rem;
}

.modal {
    background: var(--card-bg);
    border-radius: 0.75rem;
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
}

.modal-header {
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-title {
    font-size: 1.125rem;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-muted);
    line-height: 1;
}

.modal-body {
    padding: 1.5rem;
}

.modal-footer {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--border);
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
}

.table {
    width: 100%;
    border-collapse: collapse;
}

.table th, .table td {
    padding: 0.75rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

.table th {
    font-weight: 600;
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--text-muted);
}

.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.5rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 500;
}

.badge-success {
    background: rgba(34, 197, 94, 0.1);
    color: var(--success);
}

.badge-warning {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning);
}

.badge-danger {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
}

.alert {
    padding: 0.75rem 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    font-size: 0.875rem;
}

.alert-error {
    background: rgba(239, 68, 68, 0.1);
    color: var(--danger);
    border: 1px solid rgba(239, 68, 68, 0.2);
}

.alert-success {
    background: rgba(34, 197, 94, 0.1);
    color: var(--success);
    border: 1px solid rgba(34, 197, 94, 0.2);
}

.tabs {
    display: flex;
    border-bottom: 1px solid var(--border);
    margin-bottom: 1.5rem;
}

.tab {
    padding: 0.75rem 1rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-muted);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -1px;
    transition: all 0.15s ease;
}

.tab:hover {
    color: var(--text);
}

.tab.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-muted);
}

.empty-state-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.share-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem;
    background: var(--bg);
    border-radius: 0.375rem;
    font-family: monospace;
    font-size: 0.875rem;
    word-break: break-all;
}


/* User Dropdown */
.user-menu-container {
    position: relative;
    display: inline-block;
}

.user-menu-trigger {
    cursor: pointer;
    padding: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.user-dropdown {
    display: none;
    position: absolute;
    top: 100%;
    right: 0;
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    box-shadow: var(--shadow-lg);
    min-width: 150px;
    z-index: 1000;
    padding: 0.5rem 0;
}

.user-menu-container:hover .user-dropdown {
    display: block;
}

.dropdown-item {
    display: block;
    width: 100%;
    padding: 0.5rem 1rem;
    text-align: left;
    background: none;
    border: none;
    color: var(--text);
    cursor: pointer;
    font-size: 0.875rem;
    text-decoration: none;
}

.dropdown-item:hover {
    background: var(--bg);
    color: var(--primary);
}

/* Loading Spinner */
.spinner {
    width: 1em;
    height: 1em;
    border: 2px solid currentColor;
    border-right-color: transparent;
    border-radius: 50%;
    animation: spinner-rotate 0.75s linear infinite;
}

@keyframes spinner-rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* Shared Button Active State */
.btn-share-active {
    color: var(--primary);
    border-color: var(--primary);
    background: rgba(59, 130, 246, 0.05);
}

/* Mobile Adaptations */
@media (max-width: 768px) {
    .header-content {
        flex-direction: row;
        flex-wrap: wrap;
    }
    
    .logo {
        flex: 1;
    }

    .user-info {
        order: 2;
    }

    .nav {
        width: 100%;
        order: 3;
        overflow-x: auto;
        padding-top: 0.5rem;
    }

    .file-list {
        gap: 0.75rem;
    }

    .file-item {
        flex-direction: column;
        align-items: stretch;
        gap: 0.75rem;
    }

    .file-icon {
        width: 3rem;
        height: 3rem;
        font-size: 1.5rem;
        margin-right: 0;
        margin-bottom: 0.5rem;
        align-self: center;
    }
    
    .file-info {
        text-align: center;
    }

    .file-actions {
        display: flex;
        flex-wrap: wrap;
        gap: 0.5rem;
    }
    
    .file-actions .btn {
        flex: 1 0 30%; /* Auto-grow, min 30% width */
        justify-content: center;
        padding: 0.6rem 0.5rem; /* Slightly larger touch target */
    }

    .quota-bar {
        display: none; /* Hide quota bar on mobile to save space */
    }
}

/* Desktop Button Alignment */
@media (min-width: 769px) {
    .file-actions .btn {
        min-width: 80px; /* Ensure buttons have consistent width */
    }
}

.toast-container {
    position: fixed;
    top: 1rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    max-width: 500px;
    width: 90%;
}

.toast {
    padding: 1rem 1.5rem;
    border-radius: 0.5rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    font-size: 0.875rem;
    font-weight: 500;
    animation: slideDown 0.3s ease-out;
    word-wrap: break-word;
    text-align: center;
}

.toast-success {
    background: #d1fae5;
    color: #065f46;
    border: 1px solid #6ee7b7;
}

.toast-error {
    background: #fee2e2;
    color: #991b1b;
    border: 1px solid #fca5a5;
}

.toast-info {
    background: #dbeafe;
    color: #1e40af;
    border: 1px solid #93c5fd;
}

@keyframes slideDown {
    from {
        transform: translateY(-100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.progress-bar-indeterminate {
    width: 30%;
    height: 100%;
    background: linear-gradient(90deg, var(--primary) 0%, #60a5fa 50%, var(--primary) 100%);
    animation: indeterminateProgress 1.5s ease-in-out infinite;
    border-radius: 4px;
}

@keyframes indeterminateProgress {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(350%);
    }
}

.modal-large {
    max-width: 900px;
}

.preview-body {
    padding: 0;
    max-height: 80vh;
    overflow: auto;
    display: flex;
    flex-direction: column;
}

.preview-image-container {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    background: #f1f5f9;
    flex: 1;
    min-height: 0;
    overflow: hidden;
}

.preview-image {
    max-width: 100%;
    max-height: calc(80vh - 3rem);
    object-fit: contain;
    border-radius: 0.5rem;
    display: block;
}

.preview-text {
    padding: 1.5rem;
    margin: 0;
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    font-size: 0.875rem;
    line-height: 1.6;
    white-space: pre-wrap;
    word-wrap: break-word;
    background: #f8fafc;
    color: var(--text);
    overflow-x: auto;
}

.preview-loading {
    padding: 3rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 1rem;
}

.preview-error {
    padding: 3rem;
    text-align: center;
    color: var(--danger);
    font-size: 1rem;
}