Update src/streamlit_app.py

src/streamlit_app.py

@@ -1,441 +1,233 @@
 import streamlit as st
+import json
 
-# Streamlit app configuration
-st.set_page_config(page_title="M.Sc. (CS) Third Semester Syllabus", layout="wide")
-
-# Title and description
-st.title("M.Sc. (CS) Third Semester Syllabus")
-st.write("Explore the syllabus for the Third Semester of M.Sc. (Computer Science). Select a subject to view its units and detailed topics.")
-
-# Dictionary to store the syllabus data
-syllabus = {
-    "Programming in Java": {
+# --- DATA STRUCTURE ---
+# I have converted your text into a Python dictionary. 
+# This is the most crucial step for creating a dynamic app.
+# This separates the data from the presentation logic.
+syllabus_data = {
+    "Paper I: Programming in Java": {
         "UNIT-I": {
-            "Introduction": [
-                "History and features of Java",
-                "Difference between C, C++ & JAVA",
-                "JAVA and Internet, WWW, Web Browsers",
-                "Java support system, Java Environment",
-                "JDK, JVM, Byte code"
-            ],
-            "Java Programming Basics": [
-                "Structure of Java program",
-                "JAVA tokens and Statements",
-                "Constants & Variables",
-                "Data types",
-                "Operators",
-                "Command line arguments"
-            ],
-            "Java Statements & Arrays": [
-                "if and switch statement",
-                "while, do-while and for loops",
-                "Introduction to arrays, types of arrays, new operator",
-                "Strings, String class & its methods",
-                "Vectors"
-            ],
-            "Classes & Objects": [
-                "Specifying classes",
-                "Methods and fields",
-                "Creating objects",
-                "Passing objects to methods, returning objects",
-                "Static fields & methods",
-                "Constructors",
-                "Garbage collection",
-                "Overloading methods & constructors",
-                "this keyword"
-            ]
+            "Introduction": ["History and features of Java", "Difference between C, C++ & JAVA", "JAVA and Internet, WWW, Web Browsers", "Java support system, Java Environment", "JDK, JVM, Byte code"],
+            "Java Programming Basics": ["Structure of Java program", "JAVA tokens and Statements", "Constants & Variables", "Data types", "Operators", "Command line arguments"],
+            "Java Statements & Arrays": ["`if` and `switch` statement", "`while`, `do-while` and `for` loops", "Introduction to arrays, types of arrays, `new` operator", "Strings, `String` class & its methods", "Vectors"],
+            "Classes & Objects": ["Specifying classes", "Methods and fields", "Creating objects", "Passing objects to methods, returning objects", "Static fields & methods", "Constructors", "Garbage collection", "Overloading methods & constructors", "`this` keyword"]
         },
         "UNIT-II": {
-            "Inheritance": [
-                "Specifying sub class",
-                "Types of inheritance",
-                "Visibility control: public, private, protected, package",
-                "super keyword",
-                "Overriding methods",
-                "Dynamic method dispatch",
-                "Abstract methods and classes",
-                "final methods & classes"
-            ],
-            "Packages & Interfaces": [
-                "Introduction to packages, naming conventions",
-                "package statement, creating packages",
-                "import statement, accessing package",
-                "Use of CLASSPATH, adding class to package, hiding classes",
-                "Interface, implementing interfaces, multiple interfaces"
-            ],
-            "Multithreading": [
-                "Creation threads",
-                "Extending Thread class, implements Runnable interface",
-                "Stopping and blocking thread",
-                "Thread life cycle",
-                "Thread priorities & Thread synchronization",
-                "Using Thread methods"
-            ]
+            "Inheritance": ["Specifying sub class", "Types of inheritance", "Visibility control: `public`, `private`, `protected`, `package`", "`super` keyword", "Overriding methods", "Dynamic method dispatch", "Abstract methods and classes", "`final` methods & classes"],
+            "Packages & Interfaces": ["Introduction to packages, naming conventions", "`package` statement, creating packages", "`import` statement, accessing package", "Use of CLASSPATH, adding class to package, hiding classes", "Interface, implementing interfaces, multiple interfaces"],
+            "Multithreading": ["Creation threads", "Extending `Thread` class, implements `Runnable` interface", "Stopping and blocking thread", "Thread life cycle", "Thread priorities & Thread synchronization", "Using `Thread` methods"]
         },
         "UNIT-III": {
-            "Exception Handling": [
-                "Managing errors, types of errors, exceptions",
-                "Syntax of exception handling code: try, catch, throw, throws and finally statements",
-                "Multiple catch & nested try statements"
-            ],
-            "Java Input Output": [
-                "Java I/O package",
-                "Byte/Character Stream",
-                "Buffered reader / writer",
-                "File reader / writer",
-                "File Sequential / Random",
-                "Reading numeric, character & strings data from keyboard"
-            ],
-            "Applet Programming": [
-                "Applet Vs. Application",
-                "Creating applets, life cycle",
-                "Local & remote applets",
-                "<APPLET> tag & its attributes",
-                "Adding applet to HTML file, Running applet"
-            ]
+            "Exception Handling": ["Managing errors, types of errors, exceptions", "Syntax of exception handling code: `try`, `catch`, `throw`, `throws` and `finally` statements", "Multiple `catch` & nested `try` statements"],
+            "Java Input Output": ["Java I/O package", "Byte/Character Stream", "Buffered reader / writer", "File reader / writer", "File Sequential / Random", "Reading numeric, character & strings data from keyboard"],
+            "Applet Programming": ["Applet Vs. Application", "Creating applets, life cycle", "Local & remote applets", "`<APPLET>` tag & its attributes", "Adding applet to HTML file, Running applet"]
         },
         "UNIT-IV": {
-            "Abstract Windows Toolkit (AWT)": [
-                "Components and Graphics",
-                "Containers, Frames and Panels",
-                "Layout Managers: Border layout, Flow layout, Grid layout, Card layout",
-                "AWT components",
-                "Event delegation Model: Event source and handler, Event categories, Listeners, Interfaces",
-                "Controls: text box, radio buttons, checkboxes, lists, choice, command buttons, text area etc."
-            ],
-            "JDBC (Java Database Connectivity)": [
-                "Types of JDBC drivers",
-                "Writing JDBC applications",
-                "Types of statement objects: Statement, PreparedStatement and CallableStatement",
-                "Types of resultset",
-                "Inserting and updating records",
-                "JDBC and AWT"
-            ]
+            "Abstract Windows Toolkit (AWT)": ["Components and Graphics", "Containers, Frames and Panels", "Layout Managers: Border layout, Flow layout, Grid layout, Card layout", "AWT components", "Event delegation Model: Event source and handler, Event categories, Listeners, Interfaces", "Controls: text box, radio buttons, checkboxes, lists, choice, command buttons, text area etc."],
+            "JDBC (Java Database Connectivity)": ["Types of JDBC drivers", "Writing JDBC applications", "Types of statement objects: `Statement`, `PreparedStatement` and `CallableStatement`", "Types of resultset", "Inserting and updating records", "JDBC and AWT"]
         },
         "UNIT-V": {
-            "Networking with Java": [
-                "Networking basics, Sockets, port",
-                "Internet addressing",
-                "java.net – networking classes and interfaces",
-                "Implementing TCP/IP based Server and Client"
-            ],
-            "Servlets": [
-                "Introduction Servlet API Overview",
-                "Writing and running Simple Servlet, Servlet Life cycle",
-                "Generic Servlet, HTTPServlet",
-                "ServletConfig, ServletContest",
-                "Writing Servlet to handle Get and Post methods"
-            ]
+            "Networking with Java": ["Networking basics, Sockets, port", "Internet addressing", "`java.net` – networking classes and interfaces", "Implementing TCP/IP based Server and Client"],
+            "Servlets": ["Introduction Servlet API Overview", "Writing and running Simple Servlet, Servlet Life cycle", "Generic Servlet, `HTTPServlet`", "`ServletConfig`, `ServletContest`", "Writing Servlet to handle Get and Post methods"]
         }
     },
-    "Computer Graphics": {
+    "Paper II: Computer Graphics": {
         "UNIT-I": {
-            "Overview": [
-                "Introduction of computer Graphics and its applications",
-                "Overview of Graphics systems"
-            ],
-            "Video Display Devices": [
-                "Raster scan display, Raster scan systems, video controller, Raster scan display processor",
-                "Random scan display, random scan systems",
-                "Color CRT monitor",
-                "Flat panel display"
-            ],
-            "Interactive Input Devices": [
-                "Logical classification of input devices",
-                "Keyboard, mouse, Trackball and spaceball, Joysticks, Image scanner, Light pens"
-            ],
-            "Graphics Software and Coordinates": [
-                "Graphics software",
-                "Coordinates representations",
-                "Graphics functions"
-            ]
+            "Introduction": ["Introduction of computer Graphics and its applications", "Overview of Graphics systems", "Video display devices (Raster scan, Random scan, Color CRT, Flat panel)", "Interactive input devices (Keyboard, mouse, Joysticks, etc.)", "Graphics software", "Coordinates representations", "Graphics functions"]
         },
         "UNIT-II": {
-            "Algorithms": [
-                "Line drawing algorithms: DDA, Bresenham’s",
-                "Circle generating: Mid-point circle algorithm",
-                "Ellipse generating: Polynomials",
-                "Scan-line polygon fill",
-                "Boundary fill"
-            ]
+            "Algorithms": ["Line drawing algorithms: DDA, Bresenham’s", "Circle generating: Mid-point circle algorithm", "Ellipse generating: Polynomials", "Scan-line polygon fill", "Boundary fill"]
         },
         "UNIT-III": {
-            "Transformations and Clipping": [
-                "Basic transformations: Translation, Rotation, Scaling",
-                "Matrix representations & homogeneous co-ordinates",
-                "Composite transformations: Reflection",
-                "Two dimensional viewing",
-                "Two dimensional clipping: Line, Polygon, Curve, Text",
-                "3D-transformation, Projection, Viewing, Clipping"
-            ]
+            "Transformations & Viewing": ["Basic transformations: Translation, Rotation, Scaling", "Matrix representations & homogeneous co-ordinates", "Composite transformations: Reflection", "Two dimensional viewing", "Two dimensional clipping: Line, Polygon, Curve, Text", "3D-transformation, Projection, Viewing, Clipping"]
         },
         "UNIT-IV": {
-            "Splines and Hidden Surfaces": [
-                "Spline representation: Cubic spline, Bezier curve, Bezier surfaces, Beta spline, B-spline surfaces, B-spline curve",
-                "Hidden surfaces",
-                "Hidden lines",
-                "Z-buffer"
-            ]
+            "Curves & Surfaces": ["Spline representation (Cubic, Bezier, Beta, B-spline)", "Hidden surfaces", "Hidden lines", "Z-buffer"]
         },
         "UNIT-V": {
-            "Fractals and Shading": [
-                "Fractals geometry: Fractal generation procedure, Classification of Fractal, Fractal dimension, Fractal construction methods",
-                "Color models: XYZ, RGB, YIQ, CMY & HSV",
-                "Shading algorithms: Shading model, Illumination model, Gouraud shading, Phong shading"
-            ]
+            "Advanced Topics": ["Fractals geometry (Generation, Classification, Dimension, Construction)", "Color models: XYZ, RGB, YIQ, CMY & HSV", "Shading algorithms (Illumination models, Gouraud, Phong)"]
         }
     },
-    "LINUX": {
+    "Paper III: LINUX": {
         "UNIT-I": {
-            "Introduction": [
-                "Introduction to Multi-user System",
-                "Emergency and history of Unix",
-                "Feature and benefits, Versions of Unix"
-            ],
-            "System Structure": [
-                "Hardware requirements",
-                "Kernel and its function",
-                "Introduction to System calls and Shell"
-            ],
-            "File System": [
-                "Feature of Unix File System",
-                "Concept of i-node table, links",
-                "Commonly used commands (e.g., who, pwd, cd, mkdir, rm, ls, mv, lp, chmod, cp, grep, sed, awk, pr, lex, yacc, make)",
-                "Getting started (login / logout)",
-                "File system management, file operation, system calls, buffer cache"
-            ],
-            "Vi Editor": [
-                "Intro to text processing",
-                "Command and edit mode, invoking vi",
-                "Command structure, deleting and inserting line",
-                "Deleting and replacing character, searching strings, yanking",
-                "Running shell command, command macros",
-                "Set windows, set auto indent, set number, intro to exrc file"
-            ]
+            "Introduction & Basics": ["Introduction to Multi-user System, History of Unix", "System Structure: Kernel, System calls, Shell", "File System: i-node, links, commands (`who`, `pwd`, `cd`, etc.)", "Vi Editor: Command/edit mode, basic operations"]
         },
         "UNIT-II": {
-            "Shell Programming": [
-                "Introduction to shell feature, wild card characters",
-                "I/O redirections, standard error redirection",
-                "System and user created shell variables, profile files",
-                "Pipes/tee, background processing",
-                "Command line arguments, command substitution, read statement",
-                "Conditional execution of commands",
-                "Special shell variables ($ #, #?, $ * etc.)",
-                "Shift commands",
-                "Loops and decision making: for, while and until",
-                "Choice making using case...esac",
-                "Decision making if...fi",
-                "Using test, string comparison, numerical comparison, logical operation, using expr"
-            ]
+            "Shell Programming": ["Wild cards, I/O redirection, Pipes", "Shell variables, profile files", "Command line arguments, command substitution", "Conditional execution (`if...fi`)", "Loops (`for`, `while`, `until`)", "Choice making (`case...esac`)"]
         },
         "UNIT-III": {
-            "Advanced Shell": [
-                "Features, changing the login shell",
-                "cshrc, login, logout files",
-                "Setting environment variables",
-                "History and alias mechanism",
-                "Command line arguments",
-                "Redirection/appending safely, noclobber, noglob, ignore eof",
-                "Directory stacks (pushd, popd)",
-                "Feature of other shell (rsh, vsh)"
-            ],
-            "Process Control": [
-                "Process management, process states and transition",
-                "Regions and control of process",
-                "Sleep and waking",
-                "Process creation, process killing",
-                "Signals",
-                "System boot and init process",
-                "Traps",
-                "Setting process priorities"
-            ]
+            "Advanced Shell & Process Control": ["Advanced Shell features (`cshrc`, `login`, `logout`)", "History and alias mechanism", "Directory stacks (`pushd`, `popd`)", "Process management, states, and transition", "Process creation (`fork`) and killing (`kill`)", "Signals and traps"]
         },
         "UNIT-IV": {
-            "Inter-process Communication": [
-                "I/O Sub system, terminal drives, disk drives",
-                "Messages, shared memory, semaphores",
-                "Memory management, swapping, demand paging"
-            ],
-            "System Calls and Unix-C Interface": [
-                "File handling calls: access(), open(), create(), read(), write(), close(), fseek()",
-                "Process control system calls: kill(), exec(), fork(), wait(), signal(), exit()",
-                "Comparing stdio library and calls"
-            ]
+            "Inter-process Communication & System Calls": ["I/O Sub system", "IPC: Messages, shared memory, semaphores", "Memory management: swapping, demand paging", "File handling calls: `open()`, `read()`, `write()`, `close()`, `fseek()`", "Process control calls: `kill()`, `exec()`, `fork()`, `wait()`, `signal()`"]
         },
         "UNIT-V": {
-            "System Administration": [
-                "Process and Scheduling",
-                "Security",
-                "Basic System Administration: Adding a User, User Passwords, Delete of a User, Adding a Group, Deleting a Group, Super User, Startup and Shutdown",
-                "Advanced System Administration: Managing Disk Space, Backup and Restore, Managing System Services"
-            ],
-            "Xwindows": [
-                "Introduction to Xwindows concept"
-            ]
+            "System Administration & Xwindows": ["Process and Scheduling, Security", "Basic Admin: Adding/Deleting Users & Groups, Super User", "Advanced Admin: Managing Disk Space, Backup & Restore", "Introduction to Xwindows concept"]
         }
     },
-    "Image Processing": {
+    "Paper IV: Image Processing": {
         "UNIT-I": {
-            "Digital Image Fundamentals": [
-                "Introduction",
-                "An image model",
-                "Sampling & quantization",
-                "Basic relationships between Pixels",
-                "Imaging geometry"
-            ]
+            "Digital Image Fundamentals": ["Introduction, An image model", "Sampling & quantization", "Basic relationships between Pixels", "Imaging geometry"]
         },
         "UNIT-II": {
-            "Image Transforms": [
-                "Properties of 2 – D Fourier transform",
-                "FFT algorithm and other separable image transforms",
-                "Walsh transforms",
-                "Hadamard, Cosine, Haar, Slant transforms, KL transforms and their properties"
-            ]
+            "Image Transforms": ["Properties of 2-D Fourier transform", "FFT algorithm and other separable image transforms", "Walsh, Hadamard, Cosine, Haar, Slant, KL transforms"]
         },
         "UNIT-III": {
-            "Image Enhancement": [
-                "Background",
-                "Enhancement by point processing, histogram processing",
-                "Spatial filtering and enhancement in frequency domain",
-                "Color image processing"
-            ],
-            "Image Filtering and Restoration": [
-                "Degradation model",
-                "Diagnolisation of circulant and block circulate matrices",
-                "Algebraic approach to restoration",
-                "Inverse filtering, least mean squares and interactive restoration",
-                "Geometric transformations"
-            ]
+            "Image Enhancement & Restoration": ["Enhancement by point processing, histogram processing", "Spatial filtering and frequency domain enhancement", "Color image processing", "Degradation model, Inverse filtering, Restoration techniques"]
         },
         "UNIT-IV": {
-            "Image Compression": [
-                "Fundamentals",
-                "Image compression modes",
-                "Error free compression, lossy compression",
-                "Image compression standards"
-            ],
-            "Image Segmentation": [
-                "Detection of discontinuities, edge linking and boundary detection",
-                "Thresholding",
-                "Region – oriented segmentation",
-                "Use of motion in segmentation"
-            ]
+            "Image Compression & Segmentation": ["Fundamentals, Compression modes (Error free, Lossy)", "Image compression standards", "Detection of discontinuities, edge linking", "Thresholding, Region-oriented segmentation"]
         },
         "UNIT-V": {
-            "Representation and Description": [
-                "Various schemes for representation",
-                "Boundary descriptors",
-                "Regional descriptors"
-            ],
-            "Image Reconstruction": [
-                "Image reconstruction from Projections",
-                "Radon Transforms",
-                "Convolution/Filter back – Project Algorithms"
-            ]
+            "Representation & Description": ["Representation schemes, Boundary/Regional descriptors", "Image reconstruction from Projections", "Radon Transforms", "Convolution/Filter back-Project Algorithms"]
         }
     },
-    "Object Oriented Analysis And Design": {
+    "Paper V: Object Oriented Analysis And Design": {
         "UNIT-I": {
-            "Introduction": [
-                "Two views of software Developments: SSAD and OOAD",
-                "Why Object –Orientation?: Object and classes, Abstraction and encapsulation, Methods and Message, Interfaces, Inheritance and Polymorphism, Access Control",
-                "The Business case for OO Developments"
-            ],
-            "Object Oriented Methodologies": [
-                "Object Oriented Design – Booch",
-                "Object Modeling Techniques – Rumbaugh",
-                "Object – Oriented Analysis – Coad-Yourdan",
-                "Object – Oriented Software Engineering – Ivar Jacobson"
-            ]
+            "Introduction to OOAD": ["SSAD vs OOAD", "Why Object-Orientation? (Classes, Abstraction, Inheritance, Polymorphism)", "The Business case for OO Developments", "OO Methodologies (Booch, Rumbaugh, Coad-Yourdan, Jacobson)"]
         },
         "UNIT-II": {
-            "Unified Approach": [
-                "Diagramming and Notational Techniques using the UML",
-                "UML Notation",
-                "Analysis Diagramming Techniques (Introduction to all ten diagrams)",
-                "Design Diagramming Techniques",
-                "Generalization/Specialization, Aggregation and composition, Association, Cardinality, Navigability, Icons, relationships and adornments"
-            ],
-            "Object-Oriented Systems Development Process": [
-                "Rational Unified Process",
-                "Four Major phases: Inception, Elaboration, Construction, Transition"
-            ],
-            "Requirements Engineering": [
-                "Problem analysis, Understanding Stockholders need",
-                "Type of requirements",
-                "Use-case Model: Writing Requirements"
-            ]
+            "Unified Approach & Process": ["UML Notation and Diagramming Techniques", "Rational Unified Process (Inception, Elaboration, Construction, Transition)", "Requirements Engineering", "Use-case Model: Writing Requirements"]
         },
         "UNIT-III": {
-            "Analysis": [
-                "Behavioral Analysis",
-                "Domain Analysis or Business Object Analysis",
-                "Use-case Driven Object Oriented analysis: The UML approach",
-                "Develop use-case Model",
-                "Use-case Description",
-                "Documentation, Activity Diagram",
-                "Identify the classes",
-                "Introduction to different approaches for identifying classes: 'Noun Phrase' approach OR 'Conman Class Pattern' approach OR 'CRC' approach OR Use case Driven Approach",
-                "Containment and Composition, Aggregation, Inheritance",
-                "SubTypes and IS-A Hierarchies",
-                "Association and Link Relationships",
-                "Diagramming System Events"
-            ]
+            "Analysis": ["Behavioral Analysis, Domain Analysis", "Use-case Driven OO analysis", "Identifying classes (Noun Phrase, CRC, etc.)", "Relationships: Aggregation, Composition, Association, Inheritance"]
         },
         "UNIT-IV": {
-            "Design Phases": [
-                "Translating Analysis Concept into Design",
-                "Optimizing classes and Objects: The Multi-tiered Architecture View",
-                "Mapping System functions to objects",
-                "Object to Object Visibility",
-                "Collaboration Diagram",
-                "Sequential Diagram",
-                "Specification Class Diagram",
-                "Specifying Object Interfaces",
-                "Designing the Data Access layer",
-                "Design User Interface layer",
-                "Designing System Interfaces, Controls and Security"
-            ]
+            "Design Phases": ["Translating Analysis to Design", "Multi-tiered Architecture View", "Object Visibility, Collaboration & Sequential Diagrams", "Designing Data Access, User Interface, and System Interface layers"]
         },
         "UNIT-V": {
-            "Design Refinement": [
-                "Designing for Extensibility",
-                "Design for reusability",
-                "Portioning class space",
-                "Checking Completeness and correctness"
-            ],
-            "Persistent Object and Database Issues": [
-                "The Cood Data Management Domain",
-                "Object Persistence",
-                "Object-oriented Database Management System",
-                "Object-Oriented verses Relational Database",
-                "Mapping object to Relational Data structure"
-            ],
-            "Testing": [
-                "Introduction to Testing Strategies",
-                "Impact of Object Orientation on Testing",
-                "Testing Business Process",
-                "Design Matrix",
-                "Discovering reusable pattern"
-            ]
+            "Refinement & Testing": ["Design for Extensibility and Reusability", "Persistent Objects and Database Issues (OODBMS vs RDBMS)", "Testing Strategies, Impact of OO on Testing", "Testing Business Process, Design Matrix"]
         }
     }
 }
 
-# Sidebar for subject selection
-st.sidebar.header("Select Subject")
-subject = st.sidebar.selectbox("Choose a subject:", list(syllabus.keys()))
 
-# Display selected subject's units and topics
-st.header(subject)
-for unit, sections in syllabus[subject].items():
-    with st.expander(unit):
-        for section, topics in sections.items():
-            st.subheader(section)
-            for topic in topics:
-                st.write(f"- {topic}")
+# --- PAGE CONFIGURATION ---
+st.set_page_config(
+    page_title="M.Sc. CS Syllabus",
+    page_icon="🎓",
+    layout="centered",
+    initial_sidebar_state="auto"
+)
+
+
+# --- CUSTOM CSS FOR A BEAUTIFUL UI ---
+def local_css(file_name):
+    with open(file_name) as f:
+        st.markdown(f"<style>{f.read()}</style>", unsafe_allow_html=True)
+
+# You can create a style.css file or just embed it directly
+st.markdown("""
+<style>
+    /* Main app styling */
+    .stApp {
+        background-color: #f0f2f6; /* Light grey background */
+    }
+
+    /* Title styling */
+    h1 {
+        color: #0c356a; /* Dark blue */
+        text-align: center;
+        font-family: 'Verdana', sans-serif;
+    }
+
+    /* Sidebar styling */
+    .st-emotion-cache-16txtl3 {
+        background-color: #ffffff;
+        border-right: 2px solid #e0e0e0;
+    }
+    .st-emotion-cache-16txtl3 .st-emotion-cache-1y4p8pa {
+        padding-top: 2rem;
+    }
+    
+    /* Radio button styling in sidebar */
+    .st-emotion-cache-16txtl3 .st-emotion-cache-ltfnpr {
+        background-color: #e6f3ff;
+        border-radius: 0.5rem;
+        padding: 10px;
+        margin-bottom: 10px;
+    }
+
+    /* Expander styling */
+    .st-emotion-cache-sh2krr {
+        border: 1px solid #dcdcdc;
+        border-radius: 0.75rem;
+        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
+        margin-bottom: 1rem;
+        background-color: #ffffff;
+    }
+    .st-emotion-cache-sh2krr summary {
+        font-size: 1.1rem;
+        font-weight: 600;
+        color: #2c3e50; /* Darker text for header */
+    }
+
+    /* Tab styling */
+    .st-emotion-cache-1qg05j { /* Tab container */
+        border-bottom: 2px solid #0c356a;
+    }
+    button[data-baseweb="tab"][aria-selected="true"] {
+        background-color: #0c356a;
+        color: white;
+        border-radius: 0.5rem 0.5rem 0 0;
+    }
+
+</style>
+""", unsafe_allow_html=True)
+
 
-# Footer
+# --- APP LAYOUT ---
+
+# --- HEADER ---
+st.title("🎓 M.Sc. (CS) Syllabus Navigator")
+st.markdown("Welcome! Select a subject from the sidebar to explore the syllabus for the **Third Semester**.")
 st.markdown("---")
-st.markdown("Developed using Streamlit | M.Sc. (CS) Syllabus Viewer")
+
+
+# --- SIDEBAR NAVIGATION ---
+st.sidebar.title("📚 Subjects")
+st.sidebar.markdown("Choose a paper to view its syllabus:")
+
+# Get list of papers from the data
+papers = list(syllabus_data.keys())
+selected_paper = st.sidebar.radio(
+    label="M.Sc. (CS) Papers", 
+    options=papers, 
+    label_visibility="collapsed" # Hides the 'M.Sc. (CS) Papers' label above radio
+)
+
+st.sidebar.markdown("---")
+st.sidebar.info("This app provides a user-friendly view of the M.Sc. (CS) syllabus.")
+st.sidebar.markdown("Made with ❤️ by Streamlit")
+
+
+# --- MAIN CONTENT AREA ---
+
+if selected_paper:
+    # Get the details for the selected paper
+    paper_details = syllabus_data[selected_paper]
+
+    # Display the paper title in the main area
+    st.header(f"📜 {selected_paper}")
+
+    # Create tabs for each unit
+    unit_names = list(paper_details.keys())
+    tabs = st.tabs([f"**{name}**" for name in unit_names])
+
+    # Populate each tab with its content
+    for i, tab in enumerate(tabs):
+        with tab:
+            unit_name = unit_names[i]
+            unit_content = paper_details[unit_name]
+            
+            if not unit_content:
+                st.write("No topics listed for this unit.")
+                continue
+
+            # Use expanders for each topic within the unit
+            for topic, sub_topics in unit_content.items():
+                with st.expander(f"**{topic}**", expanded=(list(unit_content.keys()).index(topic) == 0)):
+                    # The first expander in each tab will be open by default
+                    for item in sub_topics:
+                        st.markdown(f"- {item}")