/* CSS Custom Properties */
:root {
    --bg-primary: #0f1117;
    --bg-secondary: #1a1d27;
    --bg-card: #232732;
    --accent: #6366f1;
    --accent-hover: #818cf8;
    --text-primary: #e2e8f0;
    --text-secondary: #94a3b8;
    --border: #2d3348;
    --success: #22c55e;
    --warning: #f59e0b;
    --error: #ef4444;
}

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

/* Base */
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Navigation */
.nav {
    position: sticky;
    top: 0;
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    z-index: 100;
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.nav-brand {
    display: flex;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: -0.02em;
}

.nav-links {
    display: flex;
    gap: 1rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    transition: all 0.2s;
}

.nav-link:hover {
    color: var(--text-primary);
    background-color: rgba(255, 255, 255, 0.05);
}

.nav-link.active {
    color: var(--accent);
    background-color: rgba(99, 102, 241, 0.1);
}

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

.user-name {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Main Content */
main {
    flex: 1;
    max-width: 1400px;
    width: 100%;
    margin: 0 auto;
    padding: 2rem;
}

/* Footer */
.footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 2rem;
    text-align: center;
}

.footer-container {
    max-width: 1400px;
    margin: 0 auto;
}

.footer p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Cards */
.card {
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

.card-header {
    margin-bottom: 1.5rem;
}

.card-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.card-description {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.project-card {
    cursor: pointer;
    transition: all 0.2s;
}

.project-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
    border-color: var(--accent);
}

/* Buttons */
.btn {
    padding: 0.625rem 1.25rem;
    border-radius: 8px;
    border: none;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
}

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

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

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

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

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

.btn-danger:hover {
    background-color: #dc2626;
}

.btn-sm {
    padding: 0.375rem 0.875rem;
    font-size: 0.8125rem;
}

.btn-lg {
    padding: 0.875rem 1.75rem;
    font-size: 1rem;
}

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

/* Forms */
.form-group {
    margin-bottom: 1.25rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 0.625rem 0.875rem;
    background-color: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 0.875rem;
    font-family: inherit;
    transition: all 0.2s;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.form-textarea {
    resize: vertical;
    min-height: 100px;
}

.form-error {
    color: var(--error);
    font-size: 0.8125rem;
    margin-top: 0.25rem;
}

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

.table th,
.table td {
    padding: 0.875rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

.table th {
    font-weight: 600;
    font-size: 0.8125rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
}

.table tbody tr {
    transition: background-color 0.2s;
}

.table tbody tr:hover {
    background-color: rgba(255, 255, 255, 0.02);
}

/* Badges */
.badge {
    display: inline-block;
    padding: 0.25rem 0.625rem;
    border-radius: 6px;
    font-size: 0.75rem;
    font-weight: 500;
}

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

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

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

.badge-info {
    background-color: rgba(99, 102, 241, 0.1);
    color: var(--accent);
}

/* Modal */
.modal-overlay {
    position: fixed;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    animation: fadeIn 0.2s;
}

.modal {
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 2rem;
    max-width: 500px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    animation: slideUp 0.3s;
}

.modal-header {
    margin-bottom: 1.5rem;
}

.modal-title {
    font-size: 1.25rem;
    font-weight: 600;
}

.modal-footer {
    margin-top: 1.5rem;
    display: flex;
    gap: 0.75rem;
    justify-content: flex-end;
}

/* Toast */
.toast-container {
    position: fixed;
    top: 1rem;
    right: 1rem;
    z-index: 2000;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.toast {
    min-width: 300px;
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
    animation: slideInRight 0.3s;
}

.toast-success {
    border-left: 3px solid var(--success);
}

.toast-error {
    border-left: 3px solid var(--error);
}

.toast-warning {
    border-left: 3px solid var(--warning);
}

.toast-info {
    border-left: 3px solid var(--accent);
}

/* File Upload */
.file-upload-zone {
    border: 2px dashed var(--border);
    border-radius: 8px;
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
}

.file-upload-zone:hover,
.file-upload-zone.dragover {
    border-color: var(--accent);
    background-color: rgba(99, 102, 241, 0.05);
}

.file-upload-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

/* Progress Bar */
.progress {
    height: 8px;
    background-color: var(--bg-primary);
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: var(--accent);
    transition: width 0.3s;
}

/* Loading Spinner */
.spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

.spinner-lg {
    width: 40px;
    height: 40px;
    border-width: 3px;
}

/* Markdown Preview */
.markdown-preview {
    background-color: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1rem;
    max-height: 400px;
    overflow-y: auto;
}

.markdown-preview h1,
.markdown-preview h2,
.markdown-preview h3 {
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
}

.markdown-preview p {
    margin-bottom: 1rem;
}

.markdown-preview code {
    background-color: var(--bg-card);
    padding: 0.125rem 0.375rem;
    border-radius: 4px;
    font-size: 0.875em;
}

.markdown-preview pre {
    background-color: var(--bg-card);
    padding: 1rem;
    border-radius: 8px;
    overflow-x: auto;
    margin-bottom: 1rem;
}

/* Utilities */
.text-center {
    text-align: center;
}

.text-secondary {
    color: var(--text-secondary);
}

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.flex {
    display: flex;
}

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

.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }
.gap-3 { gap: 1.5rem; }

.hidden {
    display: none;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

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

@keyframes slideInRight {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

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

/* Responsive */
@media (max-width: 768px) {
    .nav-container {
        padding: 0 1rem;
    }

    main {
        padding: 1rem;
    }

    .card-grid {
        grid-template-columns: 1fr;
    }

    .nav-links {
        display: none;
    }

    .modal {
        width: 95%;
        padding: 1.5rem;
    }

    .toast {
        min-width: 250px;
    }
}

/* Login/Auth Specific */
.auth-container {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: calc(100vh - 64px - 80px);
}

.auth-card {
    width: 100%;
    max-width: 420px;
}

.auth-tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 2rem;
}

.auth-tab {
    flex: 1;
    padding: 0.75rem;
    background-color: transparent;
    border: none;
    border-bottom: 2px solid var(--border);
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

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

.auth-form {
    margin-top: 2rem;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 4rem 2rem;
}

.empty-state-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

.empty-state-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.empty-state-description {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}