/* ===== Theme Variables ===== */
:root,
[data-theme="dark"] {
    --bg-body: #1e1e2e;
    --bg-toolbar: #181825;
    --bg-canvas: #1c1c30;
    --bg-oob: #0a0a10;
    --bg-input: #1e1e2e;
    --bg-context: #1e1e2e;
    --text-body: #cdd6f4;
    --text-muted: #6c7086;
    --text-icon: #a6adc8;
    --text-icon-hover: #cdd6f4;
    --border: #313244;
    --border-input: #45475a;
    --accent: #cba6f7;
    --accent-hover: #b4befe;
    --accent-bg: rgba(203, 166, 247, 0.3);
    --accent-bg-soft: rgba(203, 166, 247, 0.1);
    --grid: #2a2a3e;
    --btn-active-bg: #45475a;
    --btn-hover-bg: #313244;
    --shape-btn-color: #6c7086;
    --shape-btn-hover-color: #a6adc8;
    --shape-btn-hover-border: #45475a;
    --shadow: rgba(0, 0, 0, 0.4);
    --handle-border: #181825;
    --scrollbar-track: #181825;
    --scrollbar-thumb: #45475a;
    --scrollbar-thumb-hover: #585b70;
    --toolbar-divider: #313244;
}

[data-theme="light"] {
    --bg-body: #f8f9fa;
    --bg-toolbar: #ffffff;
    --bg-canvas: #ffffff;
    --bg-oob: #e5e5e5;
    --bg-input: #ffffff;
    --bg-context: #ffffff;
    --text-body: #333333;
    --text-muted: #888888;
    --text-icon: #666666;
    --text-icon-hover: #333333;
    --border: #e0e0e0;
    --border-input: #cccccc;
    --accent: #7c3aed;
    --accent-hover: #8b5cf6;
    --accent-bg: rgba(124, 58, 237, 0.25);
    --accent-bg-soft: rgba(124, 58, 237, 0.08);
    --grid: #dcdcdc;
    --btn-active-bg: #ede9fe;
    --btn-hover-bg: #f0f0f0;
    --shape-btn-color: #aaaaaa;
    --shape-btn-hover-color: #666666;
    --shape-btn-hover-border: #d0d0d0;
    --shadow: rgba(0, 0, 0, 0.12);
    --handle-border: #ffffff;
    --scrollbar-track: #f0f0f0;
    --scrollbar-thumb: #cccccc;
    --scrollbar-thumb-hover: #aaaaaa;
    --toolbar-divider: #e0e0e0;
}

/* ===== Reset & Base ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }

html, body {
    width: 100%; height: 100%;
    overflow: hidden;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, sans-serif;
    background: var(--bg-body);
    color: var(--text-body);
}

/* ===== Toolbar ===== */
#toolbar {
    position: fixed; top: 0; left: 0; right: 0;
    height: 52px;
    background: var(--bg-toolbar);
    border-bottom: 1px solid var(--border);
    display: flex; align-items: center;
    padding: 0 10px;
    z-index: 1000;
    gap: 3px;
}

.app-logo {
    font-size: 15px; font-weight: 700;
    color: var(--accent);
    margin-right: 8px;
    user-select: none;
    letter-spacing: -0.5px;
    white-space: nowrap;
    text-decoration: none;
    cursor: pointer;
}
.app-logo:hover {
    color: var(--accent-hover);
}

.toolbar-divider {
    width: 1px; height: 28px;
    background: var(--toolbar-divider);
    margin: 0 4px;
}

.tool-btn {
    width: 34px; height: 34px;
    border: none;
    background: transparent;
    color: var(--text-icon);
    border-radius: 6px;
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    transition: all 0.15s;
    flex-shrink: 0;
}

.tool-btn:hover { background: var(--btn-hover-bg); color: var(--text-icon-hover); }
.tool-btn.active { background: var(--btn-active-bg); color: var(--accent); box-shadow: inset 0 0 0 1.5px var(--accent); }
.tool-btn:active { transform: scale(0.95); }

/* Shape buttons in toolbar */
.shape-btn {
    width: 34px; height: 34px;
    border: 1px solid transparent;
    background: transparent;
    color: var(--shape-btn-color);
    border-radius: 6px;
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    transition: all 0.15s;
    flex-shrink: 0;
}

.shape-btn:hover { background: var(--btn-hover-bg); color: var(--shape-btn-hover-color); border-color: var(--shape-btn-hover-border); }
.shape-btn.active { background: var(--btn-active-bg); color: var(--accent); border-color: var(--accent); }

.shape-btn svg { width: 22px; height: 18px; }

/* Style controls in toolbar */
#toolbar input[type="color"] {
    width: 28px; height: 28px;
    border: 2px solid var(--border-input);
    border-radius: 4px;
    cursor: pointer;
    padding: 0;
    background: none;
    flex-shrink: 0;
}
#toolbar input[type="color"]::-webkit-color-swatch-wrapper { padding: 0; }
#toolbar input[type="color"]::-webkit-color-swatch { border: none; border-radius: 2px; }

#toolbar > input[type="number"] {
    width: 36px; height: 28px;
    background: var(--bg-input);
    border: 1px solid var(--border-input);
    border-radius: 4px;
    color: var(--text-body);
    font-size: 12px;
    text-align: center;
    padding: 2px;
    flex-shrink: 0;
}
#toolbar > input[type="number"]:focus { border-color: var(--accent); outline: none; }

#toolbar input[type="range"] {
    width: 56px; height: 4px;
    -webkit-appearance: none;
    background: var(--border-input);
    border-radius: 2px;
    outline: none;
    flex-shrink: 0;
    cursor: pointer;
}
#toolbar input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 14px; height: 14px;
    background: var(--accent);
    border-radius: 50%;
    cursor: pointer;
}

.zoom-display {
    font-size: 12px; color: var(--text-muted);
    padding: 0 6px;
    user-select: none;
    white-space: nowrap;
}

/* ===== Theme toggle ===== */
#theme-toggle {
    width: 34px; height: 34px;
    border: none;
    background: transparent;
    color: var(--text-icon);
    border-radius: 6px;
    cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    transition: all 0.15s;
    flex-shrink: 0;
    font-size: 18px;
}
#theme-toggle:hover { background: var(--btn-hover-bg); color: var(--text-icon-hover); }

/* ===== Canvas ===== */
#canvas-container {
    position: fixed; top: 52px; left: 0; right: 0; bottom: 0;
    overflow: hidden;
    background: var(--bg-oob);
}

#canvas {
    position: absolute; top: 0; left: 0;
    width: 100%; height: 100%;
    transform-origin: 0 0;
}

#grid-layer {
    position: absolute; top: 0; left: 0;
    width: 10000px; height: 10000px;
    pointer-events: none;
    z-index: 0;
    background: var(--bg-oob);
}

#shapes-layer {
    position: absolute; top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: 1;
}

#preview-layer {
    position: absolute; top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: 3;
    pointer-events: none;
}

/* ===== Shapes ===== */
.diagram-shape {
    position: absolute;
    cursor: move;
    user-select: none;
    min-width: 20px; min-height: 20px;
}

.diagram-shape:hover { filter: brightness(1.05); }
.diagram-shape.selected { box-shadow: 0 0 0 2px var(--accent), 0 0 12px var(--accent-bg); }
.diagram-shape.locked { cursor: not-allowed; opacity: 0.7; }

/* Resize handles */
.resize-handle {
    position: absolute;
    width: 10px; height: 10px;
    background: var(--accent);
    border: 2px solid var(--handle-border);
    border-radius: 2px;
    z-index: 10;
}

.resize-handle.nw { cursor: nw-resize; }
.resize-handle.ne { cursor: ne-resize; }
.resize-handle.sw { cursor: sw-resize; }
.resize-handle.se { cursor: se-resize; }
.resize-handle.n { cursor: n-resize; }
.resize-handle.s { cursor: s-resize; }
.resize-handle.w { cursor: w-resize; }
.resize-handle.e { cursor: e-resize; }
.resize-handle:hover { background: var(--accent-hover); transform: scale(1.3); }

/* Shape text */
.shape-text {
    position: absolute;
    pointer-events: none;
    font-weight: 500;
    white-space: pre-wrap; word-break: break-word;
    max-width: calc(100% - 16px); max-height: calc(100% - 16px);
    overflow: hidden;
    line-height: 1.3;
    padding: 4px;
}
.shape-text-center       { top: 50%; left: 50%; transform: translate(-50%, -50%); text-align: center; }
.shape-text-top-left      { top: 8px; left: 8px; text-align: left; }
.shape-text-top-center     { top: 8px; left: 50%; transform: translateX(-50%); text-align: center; }
.shape-text-top-right     { top: 8px; right: 8px; text-align: right; }
.shape-text-middle-left    { top: 50%; left: 8px; transform: translateY(-50%); text-align: left; }
.shape-text-middle-right   { top: 50%; right: 8px; transform: translateY(-50%); text-align: right; }
.shape-text-bottom-left    { bottom: 8px; left: 8px; text-align: left; }
.shape-text-bottom-center  { bottom: 8px; left: 50%; transform: translateX(-50%); text-align: center; }
.shape-text-bottom-right   { bottom: 8px; right: 8px; text-align: right; }

/* ===== Connections ===== */
.conn-sel { filter: brightness(1.15); }
.conn-arrow { pointer-events: none; }

/* ===== Properties Panel ===== */
#properties-panel {
    position: fixed; top: 52px; right: 0; bottom: 0;
    width: 220px;
    background: var(--bg-toolbar);
    border-left: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    z-index: 900;
    transition: width 0.2s;
}

#properties-panel.hidden { display: none; }

#properties-panel.collapsed {
    width: 36px;
    min-width: 36px;
}
#properties-panel.collapsed .panel-scroll,
#properties-panel.collapsed .panel-log,
#properties-panel.collapsed .panel-header span { display: none; }
#properties-panel.collapsed .panel-header {
    writing-mode: vertical-rl;
    padding: 8px 4px;
    border-bottom: none;
    cursor: pointer;
    flex: 1;
    justify-content: center;
    gap: 6px;
}
#properties-panel.collapsed .panel-header button {
    padding: 6px 5px;
    font-size: 14px;
    background: var(--bg-canvas);
    border: 1px solid var(--border);
    border-radius: 4px;
    color: var(--accent);
}
#properties-panel.collapsed .panel-header button:hover {
    color: var(--accent-hover);
    border-color: var(--accent);
}

.panel-scroll {
    flex: 1;
    overflow-y: auto;
}

.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px; font-weight: 600;
    color: var(--accent);
    padding: 12px;
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
}
.panel-header button {
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-canvas);
    border: 1px solid var(--border);
    color: var(--accent);
    cursor: pointer;
    padding: 4px 7px;
    border-radius: 4px;
    font-size: 14px;
    line-height: 1;
    font-weight: 700;
}
.panel-header button:hover { color: var(--accent-hover); border-color: var(--accent); background: var(--btn-hover-bg); }

.panel-section { padding: 12px; border-bottom: 1px solid var(--border); }

.panel-section label {
    display: block;
    font-size: 11px; color: var(--text-muted);
    margin-bottom: 4px; margin-top: 8px;
}
.panel-section label:first-child { margin-top: 0; }

.panel-section input[type="number"],
.panel-section input[type="color"],
.panel-section textarea {
    width: 100%;
    padding: 6px 8px;
    background: var(--bg-input);
    border: 1px solid var(--border-input);
    border-radius: 4px;
    color: var(--text-body);
    font-size: 12px;
    outline: none;
    font-family: inherit;
    resize: vertical;
}

.panel-section input[type="number"]:focus,
.panel-section input[type="color"]:focus,
.panel-section textarea:focus {
    border-color: var(--accent);
}

.panel-section input[type="color"] {
    height: 32px;
    cursor: pointer;
}

.panel-section input[type="color"]::-webkit-color-swatch-wrapper { padding: 0; }
.panel-section input[type="color"]::-webkit-color-swatch { border: none; border-radius: 2px; }

.panel-section input[type="range"] {
    width: 100%;
    height: 4px;
    -webkit-appearance: none;
    appearance: none;
    background: var(--border-input);
    border-radius: 2px;
    outline: none;
    cursor: pointer;
    margin-top: 4px;
}

.panel-section input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 14px; height: 14px;
    background: var(--accent);
    border-radius: 50%;
    cursor: pointer;
}

/* Checkbox label */
.checkbox-label {
    display: flex !important;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    color: var(--text-body) !important;
    font-size: 12px !important;
}
.checkbox-label input[type="checkbox"] {
    width: auto;
    accent-color: var(--accent);
}

/* Show/hide panel sections */
.panel-shape.hidden,
.panel-conn.hidden,
.panel-custom.hidden,
.panel-project.hidden { display: none; }

/* ===== Context Menu ===== */
#context-menu {
    position: fixed;
    background: var(--bg-context);
    border: 1px solid var(--border-input);
    border-radius: 8px;
    padding: 4px;
    min-width: 160px;
    z-index: 2000;
    box-shadow: 0 8px 24px var(--shadow);
}
#context-menu.hidden { display: none; }

.context-item {
    padding: 8px 12px;
    font-size: 13px; color: var(--text-body);
    cursor: pointer;
    border-radius: 4px;
    transition: background 0.1s;
}
.context-item:hover { background: var(--btn-hover-bg); }

.context-divider {
    height: 1px;
    background: var(--border-input);
    margin: 4px 8px;
}

/* ===== Text Editor ===== */
#text-editor { position: fixed; z-index: 1500; display: none; }
#text-editor.visible { display: block; }

#text-input {
    background: var(--bg-input);
    border: 2px solid var(--accent);
    border-radius: 4px;
    color: var(--text-body);
    font-size: 14px;
    padding: 8px;
    outline: none;
    resize: none;
    font-family: inherit;
    min-width: 100px; min-height: 40px;
}

/* ===== Selection Box ===== */
.selection-box {
    position: absolute;
    border: 1px dashed var(--accent);
    background: var(--accent-bg-soft);
    pointer-events: none;
}

/* Snap highlight during line drawing */
.snap-highlight {
    position: absolute;
    box-shadow: 0 0 0 2px var(--accent), 0 0 16px var(--accent-bg);
    pointer-events: none;
    z-index: 4;
    border-radius: 2px;
}

/* ===== Action Log (inside properties panel) ===== */
.panel-log {
    border-top: 1px solid var(--border);
    overflow: hidden;
    max-height: 24px;
    transition: max-height 0.2s;
    flex-shrink: 0;
}
.panel-log.open { max-height: 200px; }
.log-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 2px 12px;
    font-size: 11px;
    color: var(--text-muted);
    cursor: pointer;
    user-select: none;
    flex-shrink: 0;
}
.log-header button {
    background: none; border: none; color: var(--text-muted);
    cursor: pointer; font-size: 14px; padding: 0 4px;
}
.log-body {
    flex: 1;
    overflow-y: auto;
    padding: 2px 12px 6px;
    font-family: 'SF Mono', 'JetBrains Mono', monospace;
    font-size: 10px;
    color: var(--text-muted);
    line-height: 1.5;
}
.log-body .log-entry {
    padding: 1px 0;
    border-bottom: 1px solid var(--border);
}
.log-body .log-entry:last-child { border-bottom: none; }
.log-body .log-time { color: var(--accent); margin-right: 6px; }
.log-body .log-add { color: #4caf50; }
.log-body .log-del { color: #f44336; }
.log-body .log-edit { color: #ff9800; }
.log-body .log-move { color: #2196f3; }
.log-body .log-sys { color: var(--text-muted); font-style: italic; }


/* ===== Canvas size dropdown ===== */
/* ===== Export dropdown ===== */
.export-wrap { position: relative; }
.export-drop {
    position: absolute; top: 100%; right: 0; margin-top: 4px;
    background: var(--bg-toolbar); border: 1px solid var(--border);
    border-radius: 8px; padding: 4px; display: none; flex-direction: column;
    z-index: 200; min-width: 160px; box-shadow: 0 4px 16px rgba(0,0,0,0.3);
}
.export-drop.visible { display: flex; }
.export-item {
    padding: 8px 12px; font-size: 13px; color: var(--text-body);
    cursor: pointer; border-radius: 4px; user-select: none;
}
.export-item:hover { background: var(--bg-input); color: var(--accent); }

/* ===== Canvas size dropdown ===== */
.canvas-size-wrap {
    position: relative;
}
.canvas-size-drop {
    position: absolute;
    top: 100%; right: 0;
    margin-top: 4px;
    background: var(--bg-toolbar);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 10px 12px;
    display: none;
    flex-direction: column;
    gap: 6px;
    z-index: 200;
    min-width: 200px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.3);
}
.canvas-size-drop.visible {
    display: flex;
}
.canvas-size-drop label {
    font-size: 11px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.canvas-size-drop input[type="number"] {
    width: 100%;
    height: 28px;
    padding: 0 10px;
    border: 1px solid var(--border-input);
    border-radius: 6px;
    background: var(--bg-input);
    color: var(--text-body);
    font-size: 14px;
}
.canvas-size-drop input[type="number"]:focus {
    outline: none;
    border-color: var(--accent);
}

/** ===== Scrollbar ===== */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: var(--scrollbar-track); }
::-webkit-scrollbar-thumb { background: var(--scrollbar-thumb); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--scrollbar-thumb-hover); }