diff --git a/src/graph/graph.cc b/src/graph/graph.cc
index 3259c44..64b09a3 100644
--- a/src/graph/graph.cc
+++ b/src/graph/graph.cc
@@ -8,6 +8,17 @@
 
 std::string Graph::svg_demo(Analyse::track_data_t track_data) {
 
+    auto s = SvgGraph(1000, 1200);
+
+    auto *sl = new SvgLine({100, 200}, {500, 800});
+    sl->color = std::string("blue");
+    sl->dasharray = "10,5";
+    sl->opacity = 0.5;
+    s.insert(sl);
+
+    std::cout << s.dump() << std::endl;
+    return "";
+
 //    for (uint32_t i = 0; i < track_data.size(); ++i) {
 //
 //        const auto &ly = track_data[i];
diff --git a/src/graph/svg/CMakeLists.txt b/src/graph/svg/CMakeLists.txt
index 1c8e024..6ca873c 100644
--- a/src/graph/svg/CMakeLists.txt
+++ b/src/graph/svg/CMakeLists.txt
@@ -1,3 +1 @@
-cmake_minimum_required(VERSION 3.0)
-
 add_library(svg svg.cc)
diff --git a/src/graph/svg/svg.cc b/src/graph/svg/svg.cc
index 22b11e5..db05a42 100644
--- a/src/graph/svg/svg.cc
+++ b/src/graph/svg/svg.cc
@@ -1,5 +1,11 @@
 #include "svg.h"
 
+inline std::string float_to_string(float data) {
+    auto str = std::to_string(data);
+    return str.substr(0, str.find('.') + 3); // format -> xxx.__
+}
+
+/// SvgGraph interface
 void SvgGraph::insert(SvgObject *obj) {
     objects.emplace_back(obj);
 }
@@ -10,27 +16,40 @@ SvgGraph::~SvgGraph() {
     }
 }
 
-std::string SvgLine::dump() const {
+std::string SvgGraph::dump() const {
+    std::string xml = R"(<svg xmlns="http://www.w3.org/2000/svg" version="1.1")";
+    xml += " width=\"" + std::to_string(width) + "\"";
+    xml += " height=\"" + std::to_string(height) + "\">\n";
+    for (const auto *object : objects) {
+        xml += "  " + object->dump() + "\n";
+    }
+    return xml + "</svg>\n";
+}
 
+/// SvgLine render as XML content
+std::string SvgLine::dump() const {
     /// basic attributes of svg-line
-
     std::string xml = "<line ";
     xml += "x1=\"" + std::to_string(start.x) + "\" ";
     xml += "y1=\"" + std::to_string(start.y) + "\" ";
     xml += "x2=\"" + std::to_string(end.x) + "\" ";
     xml += "y2=\"" + std::to_string(end.y) + "\" ";
+    if (!dasharray.empty()) {
+        xml += "stroke-dasharray=\"" + dasharray + "\" ";
+    }
 
-    std::string style = "stroke:#636379;stroke-width:1;";
-
-    //    <line x1="0" y1="0" x2="200" y2="200" style="stroke:rgb(255,0,0);stroke-width:2"/>
-
-
-    // TODO: svg-line css style
-
+    /// style attribute of svg-line
+    std::string style = "stroke-width:" + float_to_string(width) + ";";
+    if (!color.empty()) {
+        style += "stroke:" + color + ";";
+    }
+    if (opacity != 0) {
+        style += "stroke-opacity:" + float_to_string(opacity) + ";";
+    }
     return xml + "style=\"" + style + "\" />";
-
 }
 
+/// SvgRect render as XML content
 std::string SvgRect::dump() const {
     /// basic attributes of svg-rect
     std::string xml = "<rect ";
@@ -42,7 +61,7 @@ std::string SvgRect::dump() const {
         xml += "rx=\"" + std::to_string(radius) + "\" ";
     }
     /// style attribute of svg-rect
-    std::string style = "stroke-width:" + std::to_string(stroke).substr(0, 3) + ";";
+    std::string style = "stroke-width:" + float_to_string(stroke) + ";";
     if (!color.empty()) {
         style += "fill:" + color + ";";
     }
@@ -50,20 +69,10 @@ std::string SvgRect::dump() const {
         style += "stroke:" + line_color + ";";
     }
     if (opacity != 0) {
-        style += "fill-opacity:" + std::to_string(opacity).substr(0, 4) + ";";
+        style += "fill-opacity:" + float_to_string(opacity) + ";";
     }
     if (line_opacity != 0) {
-        style += "stroke-opacity:" + std::to_string(line_opacity).substr(0, 4) + ";";
+        style += "stroke-opacity:" + float_to_string(line_opacity) + ";";
     }
     return xml + "style=\"" + style + "\" />";
 }
-
-std::string SvgGraph::dump() const {
-    std::string xml = R"(<svg xmlns="http://www.w3.org/2000/svg" version="1.1")";
-    xml += " width=\"" + std::to_string(width) + "\"";
-    xml += " height=\"" + std::to_string(height) + "\">\n";
-    for (const auto *object : objects) {
-        xml += "  " + object->dump() + "\n";
-    }
-    return xml + "</svg>\n";
-}
diff --git a/src/graph/svg/svg.h b/src/graph/svg/svg.h
index 09ab76c..1540fe5 100644
--- a/src/graph/svg/svg.h
+++ b/src/graph/svg/svg.h
@@ -11,20 +11,23 @@ public:
     uint64_t y;
 };
 
-/// basic class of SVG element
+/// SVG basic element
 class SvgObject {
 public:
     virtual ~SvgObject() = default;
     virtual std::string dump() const = 0;
 };
 
+// TODO: SVG text element
+
 /// SVG line element
 class SvgLine : public SvgObject {
 public:
-    Point start;
-    Point end;
-
-    // TODO: more options for svg-line
+    Point start, end;
+    std::string color;
+    float width = 1.0;
+    float opacity = 0;
+    std::string dasharray;
 
     ~SvgLine() override = default;
     std::string dump() const override;