:root {
    --bg-main: #0f111a;
    --bg-surface: #1a1d27;
    --bg-surface-hover: #232736;
    --bg-header: #141722;
    --text-primary: #a9b1d6;
    --text-secondary: #787c99;
    --accent: #7aa2f7;
    --accent-hover: #5d8af3;
    --accent-transparent: rgba(122, 162, 247, 0.1);
    --success: #9ece6a;
    --error: #f7768e;
    --error-bg: rgba(247, 118, 142, 0.1);
    --border-color: #292e42;
    
    --font-ui: 'Inter', sans-serif;
    --font-mono: 'Fira Code', monospace;
    
    /* Tree Colors */
    --tree-key: #7dcfff;
    --tree-string: #9ece6a;
    --tree-number: #ff9e64;
    --tree-boolean: #bb9af7;
    --tree-null: #f7768e;
}

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

body {
    font-family: var(--font-ui);
    background-color: var(--bg-main);
    color: var(--text-primary);
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
}

/* Header */
header {
    background-color: var(--bg-header);
    border-bottom: 1px solid var(--border-color);
    padding: 0 20px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    z-index: 10;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--accent);
}

.logo h1 {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text-primary);
}

.logo h1 span {
    color: var(--accent);
}

.actions {
    display: flex;
    align-items: center;
    gap: 8px;
}

.divider {
    width: 1px;
    height: 24px;
    background-color: var(--border-color);
    margin: 0 8px;
}

.btn {
    display: flex;
    align-items: center;
    gap: 6px;
    background-color: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 6px 14px;
    border-radius: 6px;
    font-family: var(--font-ui);
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn:hover {
    background-color: var(--bg-surface-hover);
    border-color: #3b4261;
}

.btn.primary {
    background-color: var(--accent);
    color: #000;
    border-color: var(--accent);
}

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

.btn svg {
    width: 14px;
    height: 14px;
}

.btn.active {
    background-color: var(--accent-transparent);
    border-color: var(--accent);
    color: var(--accent);
}

/* Error Banner */
.error-banner {
    background-color: var(--error-bg);
    color: var(--error);
    padding: 10px 20px;
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.9rem;
    font-weight: 500;
    border-bottom: 1px solid rgba(247, 118, 142, 0.2);
    transform: translateY(-100%);
    opacity: 0;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    z-index: 5;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.error-banner.show {
    transform: translateY(0);
    opacity: 1;
}

/* Main Container */
.container {
    display: flex;
    flex: 1;
    overflow: hidden;
    position: relative;
    z-index: 1;
}

.pane {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0; /* Prevents flex items from overflowing */
}

.left-pane {
    border-right: 1px solid var(--border-color);
    position: relative;
}

.pane-header {
    height: 40px;
    background-color: var(--bg-surface);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 16px;
}

.pane-header h2 {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.badge {
    background-color: var(--bg-surface-hover);
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 0.7rem;
    color: var(--accent);
    text-transform: none;
    letter-spacing: normal;
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background-color: var(--text-secondary);
}

.status-indicator.valid .dot {
    background-color: var(--success);
    box-shadow: 0 0 8px rgba(158, 206, 106, 0.5);
}

.status-indicator.invalid .dot {
    background-color: var(--error);
    box-shadow: 0 0 8px rgba(247, 118, 142, 0.5);
}

.stats {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

/* Textareas & Editors */
textarea {
    flex: 1;
    width: 100%;
    resize: none;
    background-color: var(--bg-main);
    color: var(--text-primary);
    border: none;
    padding: 16px;
    font-family: var(--font-mono);
    font-size: 14px;
    line-height: 1.5;
    outline: none;
}

textarea::placeholder {
    color: #444b6a;
}

.clear-btn {
    position: absolute;
    bottom: 20px;
    right: 20px;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background-color: var(--bg-surface-hover);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    transition: all 0.2s ease;
}

.left-pane:hover .clear-btn {
    opacity: 1;
}

.clear-btn:hover {
    background-color: var(--error);
    color: #fff;
    border-color: var(--error);
}

.output-container {
    flex: 1;
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

/* CodeMirror Overrides */
.CodeMirror {
    height: 100% !important;
    font-family: var(--font-mono);
    font-size: 14px;
    line-height: 1.5;
    background-color: var(--bg-main) !important;
}

.CodeMirror-gutters {
    background-color: var(--bg-surface) !important;
    border-right: 1px solid var(--border-color) !important;
}

.cm-s-material-palenight.CodeMirror {
    background-color: var(--bg-main);
}

/* Utilities */
.hidden {
    display: none !important;
}

/* Tree View Styles */
.tree-container {
    flex: 1;
    overflow: auto;
    padding: 16px;
    font-family: var(--font-mono);
    font-size: 14px;
    line-height: 1.6;
    background-color: var(--bg-main);
}

.tree-line {
    white-space: pre;
    display: flex;
}

.tree-node {
    margin-left: 20px;
}

.tree-node.root {
    margin-left: 0;
}

.tree-key {
    color: var(--tree-key);
}

.tree-string {
    color: var(--tree-string);
}

.tree-number {
    color: var(--tree-number);
}

.tree-boolean {
    color: var(--tree-boolean);
}

.tree-null {
    color: var(--tree-null);
}

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

.tree-toggle {
    display: inline-block;
    width: 14px;
    height: 14px;
    text-align: center;
    line-height: 14px;
    cursor: pointer;
    color: var(--text-secondary);
    user-select: none;
    margin-right: 4px;
    font-size: 10px;
    background: var(--bg-surface-hover);
    border-radius: 3px;
    transition: all 0.2s;
}

.tree-toggle:hover {
    color: var(--text-primary);
    background: var(--accent-transparent);
}

.tree-toggle.collapsed {
    transform: rotate(-90deg);
}

.tree-collapsed-indicator {
    color: var(--text-secondary);
    cursor: pointer;
    background: rgba(255,255,255,0.05);
    border-radius: 3px;
    padding: 0 4px;
    font-size: 0.9em;
}

.tree-collapsed-indicator:hover {
    background: rgba(255,255,255,0.1);
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        flex-direction: column;
    }
    .left-pane {
        border-right: none;
        border-bottom: 1px solid var(--border-color);
    }
    .actions {
        display: none; /* In a real app, maybe wrap in a dropdown or scroll horizontally */
    }
}