:root {
    --bg-color: #1e1e1e;
    --pane-bg: #252526;
    --text-color: #d4d4d4;
    --accent-color: #007acc;
    --border-color: #3e3e42;
    --hover-color: #2d2d30;
    --success-color: #4ec9b0;
    --error-color: #f44747;
    --font-mono: 'Consolas', 'Monaco', 'Courier New', monospace;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    height: 100vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

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

.app-header h1 {
    font-size: 1.2rem;
    font-weight: 500;
}

.global-controls {
    display: flex;
    gap: 10px;
}

/* Buttons & Inputs */
button, select {
    padding: 8px 16px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    cursor: pointer;
    background-color: var(--hover-color);
    color: var(--text-color);
    font-size: 0.9rem;
    transition: background 0.2s;
}

button:hover {
    background-color: #3e3e42;
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.primary-btn {
    background-color: var(--accent-color);
    border-color: var(--accent-color);
    color: white;
    font-weight: bold;
}

.primary-btn:hover {
    background-color: #0062a3;
}

/* Main Layout */
.editor-wrapper {
    flex: 1;
    display: flex;
    gap: 2px; /* Splitter look */
    background-color: var(--bg-color);
    padding: 10px;
}

.editor-pane {
    flex: 1;
    display: flex;
    flex-direction: column;
    background-color: var(--pane-bg);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    min-width: 0; /* Prevents flex overflow */
    position: relative;
    transition: all 0.3s ease;
}

/* Toolbar inside panes */
.toolbar {
    padding: 8px 12px;
    background-color: var(--hover-color);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.label {
    font-weight: bold;
    font-size: 0.85rem;
    text-transform: uppercase;
    color: #858585;
}

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

.icon-btn {
    padding: 4px 8px;
    font-size: 0.8rem;
    background: transparent;
    border: none;
}

.close-fs-btn {
    display: none; /* Hidden by default */
    color: var(--error-color);
}

#status-msg {
    font-size: 0.8rem;
    margin-right: 10px;
    opacity: 0;
    transition: opacity 0.3s;
}

#status-msg.error {
    color: var(--error-color);
    opacity: 1;
}

#status-msg.success {
    color: var(--success-color);
    opacity: 1;
}

/* Textareas */
textarea {
    flex: 1;
    width: 100%;
    background-color: var(--bg-color);
    color: var(--text-color);
    border: none;
    padding: 15px;
    font-family: var(--font-mono);
    font-size: 14px;
    line-height: 1.5;
    resize: none; /* Handled by flexbox */
    outline: none;
}

textarea:focus {
    background-color: #1a1a1a;
}

/* Full Screen Mode */
.editor-pane.fullscreen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 1000;
    border: none;
    border-radius: 0;
}

.editor-pane.fullscreen .close-fs-btn {
    display: inline-block;
}

.editor-pane.fullscreen .icon-btn[title="Full Screen"] {
    display: none;
}

/* Responsive */
@media (max-width: 768px) {
    .editor-wrapper {
        flex-direction: column;
    }
    
    .app-header h1 {
        display: none; /* Save space on mobile */
    }
    
    .global-controls {
        width: 100%;
        justify-content: space-between;
    }
}