/* ================================================================
   VARIABLES & RESET
   ================================================================ */

:root {
    --color-bg: #fafaf8;
    --color-bg-secondary: #ffffff;
    --color-text-primary: #1a1a18;
    --color-text-secondary: #75756f;
    --color-border: #e8e8e4;
    --color-accent-primary: #2563eb;
    --color-success: #16a34a;
    --color-danger: #dc2626;
    
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'Menlo', 'Monaco', monospace;
    
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    
    --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 20px 25px -5px rgba(0,0,0,0.1);
}

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

html {
    font-size: 16px;
}

body {
    font-family: var(--font-body);
    background-color: var(--color-bg);
    color: var(--color-text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* ================================================================
   LAYOUT
   ================================================================ */

.container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

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

.header-content {
    max-width: 1600px;
    margin: 0 auto;
    padding: var(--spacing-lg) var(--spacing-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.logo-section h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

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

.header-actions {
    display: flex;
    gap: var(--spacing-md);
}

.main-content {
    flex: 1;
    display: flex;
    max-width: 1600px;
    width: 100%;
    margin: 0 auto;
    gap: var(--spacing-xl);
    padding: var(--spacing-xl);
}

.sidebar {
    width: 220px;
    flex-shrink: 0;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.editor {
    flex: 1;
    min-height: 600px;
}

/* ================================================================
   BUTTONS
   ================================================================ */

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid transparent;
    border-radius: 0.5rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    font-family: var(--font-body);
    white-space: nowrap;
    user-select: none;
}

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

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

.btn-primary:hover:not(:disabled) {
    background-color: #1d4ed8;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

.btn-secondary:hover:not(:disabled) {
    background-color: var(--color-bg);
    border-color: var(--color-text-secondary);
}

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

.btn-success:hover:not(:disabled) {
    background-color: #15803d;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

.btn-danger:hover:not(:disabled) {
    background-color: #b91c1c;
}

.btn-large {
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 1.125rem;
}

.btn-small {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.875rem;
}

.icon {
    display: inline-flex;
    font-size: 1.2em;
}

/* ================================================================
   FORMS
   ================================================================ */

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    font-size: 0.875rem;
}

.input-with-emoji {
    display: flex;
    align-items: center;
    border: 1px solid var(--color-border);
    border-radius: 0.5rem;
    overflow: hidden;
}

.emoji-picker-trigger {
    padding: var(--spacing-md);
    font-size: 1.5rem;
    cursor: pointer;
    background-color: var(--color-bg);
    border-right: 1px solid var(--color-border);
    user-select: none;
}

input[type="text"],
input[type="url"],
textarea {
    flex: 1;
    border: 1px solid var(--color-border);
    border-radius: 0.5rem;
    padding: var(--spacing-md);
    font-size: 1rem;
    font-family: var(--font-body);
    color: var(--color-text-primary);
    transition: border-color var(--transition-fast);
}

.input-with-emoji input {
    border: none;
    padding: var(--spacing-md);
}

input:focus,
textarea:focus {
    outline: none;
    border-color: var(--color-accent-primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
    margin-top: var(--spacing-xl);
}

.emoji-picker {
    background-color: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 0.5rem;
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.emoji-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(2rem, 1fr));
    gap: var(--spacing-xs);
}

.emoji-item {
    padding: var(--spacing-sm);
    cursor: pointer;
    border-radius: 0.375rem;
    font-size: 1.5rem;
    text-align: center;
    transition: background-color var(--transition-fast);
    user-select: none;
}

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

/* ================================================================
   CATEGORIES
   ================================================================ */

.categories-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.category {
    background-color: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 0.75rem;
    overflow: hidden;
    transition: all var(--transition-base);
    animation: slideIn var(--transition-base);
}

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

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

.category-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    background-color: var(--color-bg-secondary);
    border-bottom: 1px solid var(--color-border);
    cursor: grab;
    user-select: none;
}

.category-title-section {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    flex: 1;
}

.category-emoji {
    font-size: 2rem;
}

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

.category-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.category-actions .btn {
    padding: var(--spacing-sm);
}

.category-content {
    padding: var(--spacing-lg);
}

.feeds-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.feed-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md);
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: 0.5rem;
    transition: all var(--transition-fast);
    cursor: grab;
    user-select: none;
}

.feed-item:hover {
    background-color: var(--color-bg-secondary);
    border-color: var(--color-accent-primary);
}

.feed-item.dragging {
    opacity: 0.6;
    box-shadow: var(--shadow-lg);
}

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

.feed-title {
    font-weight: 500;
    margin-bottom: var(--spacing-xs);
    word-break: break-word;
}

.feed-url {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    word-break: break-all;
    font-family: var(--font-mono);
}

.feed-status {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: 0.375rem;
    font-size: 0.875rem;
    margin-top: var(--spacing-xs);
}

.feed-status.valid {
    background-color: rgba(22, 163, 74, 0.1);
    color: var(--color-success);
}

.feed-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.feed-actions .btn {
    padding: var(--spacing-sm);
    font-size: 0.875rem;
}

.add-feed-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    width: 100%;
    padding: var(--spacing-md);
    border: 2px dashed var(--color-border);
    border-radius: 0.5rem;
    background-color: transparent;
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
    font-size: 0.875rem;
}

.add-feed-btn:hover {
    border-color: var(--color-accent-primary);
    color: var(--color-accent-primary);
    background-color: rgba(37, 99, 235, 0.05);
}

/* ================================================================
   EMPTY STATE
   ================================================================ */

.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-2xl);
    text-align: center;
    color: var(--color-text-secondary);
}

.empty-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-lg);
}

.empty-state h2 {
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-sm);
}

/* ================================================================
   MODALS
   ================================================================ */

.modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background-color: var(--color-bg-secondary);
    border-radius: 0.75rem;
    box-shadow: var(--shadow-lg);
    width: 90%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    animation: slideUp var(--transition-base);
}

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

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

.modal-header h2 {
    font-size: 1.125rem;
    margin: 0;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--color-text-secondary);
    padding: 0;
}

.modal-close:hover {
    color: var(--color-text-primary);
}

.form {
    padding: var(--spacing-lg);
}

.validation-status {
    padding: var(--spacing-md);
    border-radius: 0.5rem;
    margin-bottom: var(--spacing-md);
    font-size: 0.875rem;
}

.validation-status.hidden {
    display: none;
}

.validation-status.valid {
    background-color: rgba(22, 163, 74, 0.1);
    color: var(--color-success);
    border: 1px solid var(--color-success);
}

.validation-status.invalid {
    background-color: rgba(220, 38, 38, 0.1);
    color: var(--color-danger);
    border: 1px solid var(--color-danger);
}

.validation-status.checking {
    background-color: rgba(234, 88, 12, 0.1);
    color: #ea580c;
    border: 1px solid #ea580c;
}

/* ================================================================
   SEARCH & HISTORY
   ================================================================ */

.search-panel,
.history-panel {
    background-color: var(--color-bg-secondary);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-lg);
    max-width: 1600px;
    margin: 0 auto;
    width: 100%;
}

.search-panel.hidden,
.history-panel.hidden {
    display: none;
}

.search-input {
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    border: 2px solid var(--color-border);
    border-radius: 0.5rem;
    font-size: 1rem;
    margin-bottom: var(--spacing-md);
}

.search-results {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.search-result-item {
    padding: var(--spacing-md);
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.search-result-item:hover {
    background-color: var(--color-bg-secondary);
    border-color: var(--color-accent-primary);
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
}

.history-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.history-item {
    padding: var(--spacing-md);
    background-color: var(--color-bg);
    border: 1px solid var(--color-border);
    border-radius: 0.5rem;
    font-size: 0.875rem;
}

.history-time {
    color: var(--color-text-secondary);
    font-size: 0.75rem;
}

/* ================================================================
   ACTIONS GROUP
   ================================================================ */

.actions-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--color-border);
}

.actions-group:last-child {
    border-bottom: none;
}

.actions-group .btn {
    width: 100%;
    justify-content: center;
}

/* ================================================================
   TOAST NOTIFICATIONS
   ================================================================ */

.toast-container {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.toast {
    background-color: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 0.5rem;
    padding: var(--spacing-md) var(--spacing-lg);
    box-shadow: var(--shadow-lg);
    animation: slideInRight var(--transition-base);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    max-width: 400px;
}

@keyframes slideInRight {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.toast.success {
    border-left: 4px solid var(--color-success);
    color: var(--color-success);
}

.toast.error {
    border-left: 4px solid var(--color-danger);
    color: var(--color-danger);
}

/* ================================================================
   RESPONSIVE
   ================================================================ */

@media (max-width: 1024px) {
    .main-content {
        flex-direction: column;
        gap: var(--spacing-lg);
    }

    .sidebar {
        width: 100%;
        flex-direction: row;
        flex-wrap: wrap;
    }

    .actions-group {
        flex: 1;
        min-width: 200px;
    }
}

@media (max-width: 640px) {
    .header-content {
        flex-direction: column;
        gap: var(--spacing-lg);
        text-align: center;
    }

    .logo-section h1 {
        font-size: 1.5rem;
    }

    .main-content {
        padding: var(--spacing-md);
    }

    .sidebar {
        width: 100%;
    }

    .modal-content {
        width: 95%;
    }

    .toast {
        max-width: 90vw;
    }

    .toast-container {
        bottom: var(--spacing-md);
        right: var(--spacing-md);
    }
}

/* ================================================================
   UTILITY
   ================================================================ */

.hidden {
    display: none !important;
}