/**
 * AI Pulse Newsletter - Stylesheet
 * Clean, minimal design for busy professionals
 */

/* CSS Variables */
:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-primary-light: #dbeafe;
    --color-success: #059669;
    --color-success-light: #d1fae5;
    --color-warning: #d97706;
    --color-warning-light: #fef3c7;
    --color-danger: #dc2626;
    --color-danger-light: #fee2e2;
    --color-info: #0891b2;
    --color-info-light: #cffafe;

    --color-text: #1f2937;
    --color-text-light: #6b7280;
    --color-text-muted: #9ca3af;

    --color-bg: #f9fafb;
    --color-bg-white: #ffffff;
    --color-border: #e5e7eb;
    --color-border-dark: #d1d5db;

    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);

    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'SF Mono', Monaco, 'Cascadia Code', monospace;

    --sidebar-width: 240px;
    --header-height: 60px;
}

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

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
}

body {
    font-family: var(--font-sans);
    font-size: 0.9375rem;
    line-height: 1.5;
    color: var(--color-text);
    background: var(--color-bg);
    min-height: 100vh;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.25;
    margin-bottom: 0.5rem;
}

h1 { font-size: 1.75rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.125rem; }

p { margin-bottom: 1rem; }

a {
    color: var(--color-primary);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* Layout */
.app-container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: var(--sidebar-width);
    background: var(--color-bg-white);
    border-right: 1px solid var(--color-border);
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    overflow-y: auto;
    z-index: 100;
}

.sidebar-header {
    padding: 1.25rem;
    border-bottom: 1px solid var(--color-border);
}

.sidebar-logo {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--color-text);
}

.sidebar-nav {
    padding: 1rem 0;
}

.nav-item {
    display: block;
    padding: 0.625rem 1.25rem;
    color: var(--color-text-light);
    font-weight: 500;
    transition: all 0.15s;
}

.nav-item:hover {
    background: var(--color-bg);
    color: var(--color-text);
    text-decoration: none;
}

.nav-item.active {
    background: var(--color-primary-light);
    color: var(--color-primary);
    border-right: 3px solid var(--color-primary);
}

.nav-section {
    padding: 0.75rem 1.25rem 0.5rem;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    min-height: 100vh;
}

.page-header {
    background: var(--color-bg-white);
    border-bottom: 1px solid var(--color-border);
    padding: 1.25rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.page-title {
    margin: 0;
    font-size: 1.5rem;
}

.page-content {
    padding: 2rem;
}

/* Cards */
.card {
    background: var(--color-bg-white);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    margin-bottom: 1.5rem;
}

.card-header {
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.card-title {
    font-size: 1rem;
    font-weight: 600;
    margin: 0;
}

.card-body {
    padding: 1.25rem;
}

.card-footer {
    padding: 1rem 1.25rem;
    border-top: 1px solid var(--color-border);
    background: var(--color-bg);
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--color-bg-white);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 1.25rem;
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-text);
    line-height: 1;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--color-text-light);
    margin-top: 0.25rem;
}

.stat-card.primary { border-left: 4px solid var(--color-primary); }
.stat-card.success { border-left: 4px solid var(--color-success); }
.stat-card.warning { border-left: 4px solid var(--color-warning); }
.stat-card.danger { border-left: 4px solid var(--color-danger); }

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    font-weight: 500;
    line-height: 1.5;
    border: 1px solid transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.15s;
    text-decoration: none;
}

.btn:hover {
    text-decoration: none;
}

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

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

.btn-secondary {
    background: var(--color-bg);
    border-color: var(--color-border-dark);
    color: var(--color-text);
}

.btn-secondary:hover {
    background: var(--color-border);
}

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

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

.btn-sm {
    padding: 0.25rem 0.625rem;
    font-size: 0.8125rem;
}

.btn-lg {
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
}

.btn-block {
    display: flex;
    width: 100%;
}

.btn-group {
    display: inline-flex;
    gap: 0.5rem;
}

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

.form-group label {
    display: block;
    font-weight: 500;
    margin-bottom: 0.375rem;
    color: var(--color-text);
}

.form-control {
    width: 100%;
    padding: 0.5rem 0.75rem;
    font-size: 0.9375rem;
    line-height: 1.5;
    color: var(--color-text);
    background: var(--color-bg-white);
    border: 1px solid var(--color-border-dark);
    border-radius: var(--radius-sm);
    transition: border-color 0.15s, box-shadow 0.15s;
}

.form-control:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

.form-control::placeholder {
    color: var(--color-text-muted);
}

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

select.form-control {
    cursor: pointer;
}

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

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

/* Tables */
.table-container {
    overflow-x: auto;
}

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

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

.table th {
    font-weight: 600;
    color: var(--color-text-light);
    font-size: 0.8125rem;
    text-transform: uppercase;
    letter-spacing: 0.025em;
    background: var(--color-bg);
}

.table tbody tr:hover {
    background: var(--color-bg);
}

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

/* Badges */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.125rem 0.5rem;
    font-size: 0.75rem;
    font-weight: 500;
    border-radius: 9999px;
    text-transform: capitalize;
}

.badge-primary {
    background: var(--color-primary-light);
    color: var(--color-primary);
}

.badge-success {
    background: var(--color-success-light);
    color: var(--color-success);
}

.badge-warning {
    background: var(--color-warning-light);
    color: var(--color-warning);
}

.badge-danger {
    background: var(--color-danger-light);
    color: var(--color-danger);
}

.badge-info {
    background: var(--color-info-light);
    color: var(--color-info);
}

.badge-secondary {
    background: var(--color-bg);
    color: var(--color-text-light);
}

/* Alerts */
.alert {
    padding: 1rem 1.25rem;
    border-radius: var(--radius-md);
    margin-bottom: 1rem;
}

.alert-success {
    background: var(--color-success-light);
    color: var(--color-success);
    border: 1px solid var(--color-success);
}

.alert-error {
    background: var(--color-danger-light);
    color: var(--color-danger);
    border: 1px solid var(--color-danger);
}

.alert-warning {
    background: var(--color-warning-light);
    color: var(--color-warning);
    border: 1px solid var(--color-warning);
}

.alert-info {
    background: var(--color-info-light);
    color: var(--color-info);
    border: 1px solid var(--color-info);
}

/* Login Page */
.login-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: linear-gradient(135deg, var(--color-primary-light) 0%, var(--color-bg) 100%);
}

.login-container {
    width: 100%;
    max-width: 400px;
    padding: 1rem;
}

.login-box {
    background: var(--color-bg-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 2rem;
    text-align: center;
}

.login-box h1 {
    color: var(--color-primary);
    margin-bottom: 0.25rem;
}

.login-subtitle {
    color: var(--color-text-light);
    margin-bottom: 1.5rem;
}

.login-form {
    text-align: left;
}

.login-form .form-group {
    margin-bottom: 1.5rem;
}

/* Article Cards */
.article-card {
    background: var(--color-bg-white);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 1.25rem;
    margin-bottom: 1rem;
    transition: box-shadow 0.15s;
}

.article-card:hover {
    box-shadow: var(--shadow-md);
}

.article-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 0.75rem;
}

.article-title {
    font-size: 1rem;
    font-weight: 600;
    margin: 0;
    line-height: 1.4;
}

.article-title a {
    color: var(--color-text);
}

.article-title a:hover {
    color: var(--color-primary);
}

.article-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    font-size: 0.8125rem;
    color: var(--color-text-light);
    margin-bottom: 0.75rem;
}

.article-summary {
    color: var(--color-text);
    margin-bottom: 1rem;
    line-height: 1.6;
}

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

.article-score {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2rem;
    height: 2rem;
    background: var(--color-primary-light);
    color: var(--color-primary);
    font-weight: 600;
    border-radius: 50%;
    font-size: 0.875rem;
}

.article-score.high { background: var(--color-success-light); color: var(--color-success); }
.article-score.medium { background: var(--color-warning-light); color: var(--color-warning); }
.article-score.low { background: var(--color-danger-light); color: var(--color-danger); }

/* Newsletter Builder */
.newsletter-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.category-section {
    background: var(--color-bg-white);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.category-header {
    padding: 1rem 1.25rem;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    font-weight: 600;
}

.category-articles {
    min-height: 100px;
    padding: 0.5rem;
}

.category-articles.drag-over {
    background: var(--color-primary-light);
}

.sortable-article {
    background: var(--color-bg-white);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    padding: 0.75rem;
    margin: 0.5rem;
    cursor: move;
}

.sortable-article:hover {
    border-color: var(--color-primary);
}

.sortable-article.dragging {
    opacity: 0.5;
}

/* Modal */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--color-bg-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 600px;
    max-height: 90vh;
    overflow: auto;
    transform: scale(0.95);
    transition: transform 0.2s;
}

.modal-overlay.active .modal {
    transform: scale(1);
}

.modal-header {
    padding: 1.25rem;
    border-bottom: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin: 0;
}

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

.modal-body {
    padding: 1.25rem;
}

.modal-footer {
    padding: 1rem 1.25rem;
    border-top: 1px solid var(--color-border);
    display: flex;
    justify-content: flex-end;
    gap: 0.5rem;
}

/* Utilities */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-muted { color: var(--color-text-muted); }
.text-success { color: var(--color-success); }
.text-danger { color: var(--color-danger); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }

.d-flex { display: flex; }
.align-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }

.hidden { display: none; }

/* Loading Spinner */
.spinner {
    display: inline-block;
    width: 1.25rem;
    height: 1.25rem;
    border: 2px solid var(--color-border);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem 2rem;
    color: var(--color-text-light);
}

.empty-state-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 0.5rem;
}

/* Filters */
.filters {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    padding: 1rem 1.25rem;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
}

.filter-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.filter-group label {
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--color-text-light);
}

.filter-group select,
.filter-group input {
    padding: 0.375rem 0.625rem;
    font-size: 0.875rem;
    border: 1px solid var(--color-border-dark);
    border-radius: var(--radius-sm);
}

/* Character Counter */
.char-counter {
    font-size: 0.75rem;
    color: var(--color-text-muted);
    text-align: right;
    margin-top: 0.25rem;
}

.char-counter.warning {
    color: var(--color-warning);
}

.char-counter.danger {
    color: var(--color-danger);
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.3s;
    }

    .sidebar.open {
        transform: translateX(0);
    }

    .main-content {
        margin-left: 0;
    }

    .page-header {
        padding: 1rem;
    }

    .page-content {
        padding: 1rem;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .form-row {
        grid-template-columns: 1fr;
    }
}