/* ═══════════════════════════════════════════
   CANVAS — Panel lateral de documentos
   ═══════════════════════════════════════════ */

/* Panel */
.canvas-panel {
    position: fixed;
    top: 0;
    right: -50vw;
    width: 50vw;
    height: 100vh;
    background: var(--bg-primary);
    border-left: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    z-index: 100;
    transition: right 0.3s ease;
    box-shadow: -4px 0 20px rgba(0,0,0,0.15);
}
.canvas-panel.open {
    right: 0;
}

/* Cuando canvas esta abierto, el main se encoge */
#main.canvas-active {
    margin-right: 50vw;
    transition: margin-right 0.3s ease;
}

/* Header */
.canvas-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 16px;
    border-bottom: 1px solid var(--border);
    min-height: 52px;
    flex-shrink: 0;
}
.canvas-header-left {
    display: flex;
    align-items: center;
    gap: 10px;
    flex: 1;
    min-width: 0;
}
.canvas-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.canvas-toolbar {
    display: flex;
    gap: 4px;
    flex-shrink: 0;
}
.canvas-toolbar button {
    padding: 6px 10px;
    border: 1px solid var(--border);
    border-radius: 6px;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    font-size: 12px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 4px;
    transition: all 0.15s;
    white-space: nowrap;
}
.canvas-toolbar button:hover {
    background: var(--bg-hover);
    border-color: var(--accent);
    color: var(--text-primary);
}
.canvas-toolbar button.active {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
}
.canvas-close-btn {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: none !important;
    background: none !important;
    font-size: 18px;
    color: var(--text-muted);
    cursor: pointer;
    border-radius: 6px;
}
.canvas-close-btn:hover {
    background: var(--bg-hover) !important;
    color: var(--text-primary);
}

/* Body */
.canvas-body {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
}

/* Preview mode */
.canvas-preview {
    font-size: 15px;
    line-height: 1.7;
    color: var(--text-primary);
}
.canvas-preview h1 { font-size: 22px; margin: 24px 0 12px; font-weight: 600; }
.canvas-preview h2 { font-size: 18px; margin: 20px 0 10px; font-weight: 600; }
.canvas-preview h3 { font-size: 16px; margin: 16px 0 8px; font-weight: 600; }
.canvas-preview p { margin: 0 0 12px; }
.canvas-preview ul, .canvas-preview ol { margin: 0 0 12px; padding-left: 24px; }
.canvas-preview li { margin-bottom: 4px; }
.canvas-preview blockquote {
    border-left: 3px solid var(--accent);
    margin: 12px 0;
    padding: 8px 16px;
    color: var(--text-secondary);
    background: var(--bg-secondary);
    border-radius: 0 6px 6px 0;
}
.canvas-preview pre {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 12px 16px;
    overflow-x: auto;
    font-size: 13px;
    margin: 12px 0;
}
.canvas-preview code {
    font-family: 'JetBrains Mono', monospace;
    font-size: 13px;
}
.canvas-preview table {
    width: 100%;
    border-collapse: collapse;
    margin: 12px 0;
    font-size: 14px;
}
.canvas-preview th, .canvas-preview td {
    border: 1px solid var(--border);
    padding: 8px 12px;
    text-align: left;
}
.canvas-preview th {
    background: var(--bg-secondary);
    font-weight: 600;
}

/* Edit mode */
.canvas-editor {
    width: 100%;
    height: 100%;
    min-height: 400px;
    padding: 0;
    border: none;
    background: transparent;
    color: var(--text-primary);
    font-family: 'JetBrains Mono', monospace;
    font-size: 14px;
    line-height: 1.6;
    resize: none;
    outline: none;
}

/* AI bar */
.canvas-ai-bar {
    display: flex;
    gap: 8px;
    padding: 12px 16px;
    border-top: 1px solid var(--border);
    background: var(--bg-secondary);
    flex-shrink: 0;
}
.canvas-ai-input {
    flex: 1;
    padding: 10px 14px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 13px;
    outline: none;
}
.canvas-ai-input:focus {
    border-color: var(--accent);
}
.canvas-ai-input::placeholder {
    color: var(--text-muted);
}
.canvas-ai-send {
    padding: 10px 16px;
    border: none;
    border-radius: 8px;
    background: var(--accent);
    color: #fff;
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    white-space: nowrap;
    transition: opacity 0.15s;
}
.canvas-ai-send:hover { opacity: 0.85; }
.canvas-ai-send:disabled { opacity: 0.5; cursor: wait; }

/* Selection toolbar */
.canvas-sel-toolbar {
    position: absolute;
    display: flex;
    gap: 2px;
    padding: 4px;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 8px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.15);
    z-index: 200;
}
.canvas-sel-toolbar button {
    padding: 6px 10px;
    border: none;
    border-radius: 5px;
    background: none;
    color: var(--text-secondary);
    font-size: 12px;
    cursor: pointer;
    white-space: nowrap;
    transition: all 0.15s;
}
.canvas-sel-toolbar button:hover {
    background: var(--bg-hover);
    color: var(--accent);
}

/* Canvas open button on messages */
.msg-canvas-btn {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 3px 8px;
    border: 1px solid var(--border);
    border-radius: 6px;
    background: var(--bg-secondary);
    color: var(--text-muted);
    font-size: 11px;
    cursor: pointer;
    transition: all 0.15s;
}
.msg-canvas-btn:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(79,172,254,0.08);
}

/* Loading spinner in canvas */
.canvas-loading {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
    color: var(--text-muted);
    font-size: 14px;
    gap: 10px;
}
.canvas-spinner {
    width: 20px;
    height: 20px;
    border: 2px solid var(--border);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: canvas-spin 0.6s linear infinite;
}
@keyframes canvas-spin { to { transform: rotate(360deg); } }

/* ═══ RESPONSIVE ═══ */
@media (max-width: 1024px) {
    .canvas-panel {
        width: 100vw;
        right: -100vw;
    }
    #main.canvas-active {
        margin-right: 0;
    }
    .canvas-toolbar button span.btn-label {
        display: none;
    }
}
@media (max-width: 600px) {
    .canvas-body { padding: 16px; }
    .canvas-header { padding: 10px 12px; }
    .canvas-ai-bar { padding: 10px 12px; }
}