From b8edbcb40378c74c6e70abd111e1bc258d1c12f4 Mon Sep 17 00:00:00 2001
From: Atridad Lahiji <me@atri.dad>
Date: Thu, 23 Apr 2026 22:33:33 -0600
Subject: [PATCH] Basic structure

---
 .gitignore                 |  12 +
 go.mod                     |   9 +
 go.sum                     |   6 +
 lib/db.go                  | 121 +++++
 main.go                    | 166 +++++++
 static/styles/main.css     | 873 +++++++++++++++++++++++++++++++++++++
 templates/index.html       | 150 +++++++
 templates/login.html       |  80 ++++
 templates/ping_result.html |   9 +
 templates/register.html    |  93 ++++
 10 files changed, 1519 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 go.mod
 create mode 100644 go.sum
 create mode 100644 lib/db.go
 create mode 100644 main.go
 create mode 100644 static/styles/main.css
 create mode 100644 templates/index.html
 create mode 100644 templates/login.html
 create mode 100644 templates/ping_result.html
 create mode 100644 templates/register.html

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..507dc0c
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,12 @@
+# binary
+sprintpadawan
+
+# sqlite db
+app.db
+
+# env
+.env
+
+# os
+.DS_Store
+Thumbs.db
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..7dd4c55
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,9 @@
+module sprintpadawan
+
+go 1.26.1
+
+require (
+	github.com/google/uuid v1.6.0 // indirect
+	github.com/mattn/go-sqlite3 v1.14.42 // indirect
+	golang.org/x/crypto v0.50.0 // indirect
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..97e89ce
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,6 @@
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/mattn/go-sqlite3 v1.14.42 h1:MigqEP4ZmHw3aIdIT7T+9TLa90Z6smwcthx+Azv4Cgo=
+github.com/mattn/go-sqlite3 v1.14.42/go.mod h1:pjEuOr8IwzLJP2MfGeTb0A35jauH+C2kbHKBr7yXKVQ=
+golang.org/x/crypto v0.50.0 h1:zO47/JPrL6vsNkINmLoo/PH1gcxpls50DNogFvB5ZGI=
+golang.org/x/crypto v0.50.0/go.mod h1:3muZ7vA7PBCE6xgPX7nkzzjiUq87kRItoJQM1Yo8S+Q=
diff --git a/lib/db.go b/lib/db.go
new file mode 100644
index 0000000..288a515
--- /dev/null
+++ b/lib/db.go
@@ -0,0 +1,121 @@
+package lib
+
+import (
+	"database/sql"
+	"log"
+	"time"
+
+	"github.com/google/uuid"
+	_ "github.com/mattn/go-sqlite3"
+	"golang.org/x/crypto/bcrypt"
+)
+
+var DB *sql.DB
+
+type User struct {
+	ID           int
+	Username     string
+	PasswordHash string
+}
+
+// init sqlite db — always creates app.db at project root (run from root)
+func InitDB() {
+	var err error
+	DB, err = sql.Open("sqlite3", "./app.db")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// make users table
+	userTable := `
+	CREATE TABLE IF NOT EXISTS users (
+		id INTEGER PRIMARY KEY AUTOINCREMENT,
+		username TEXT UNIQUE NOT NULL,
+		password_hash TEXT NOT NULL
+	);`
+	_, err = DB.Exec(userTable)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// make sessions table
+	sessionTable := `
+	CREATE TABLE IF NOT EXISTS sessions (
+		id TEXT PRIMARY KEY,
+		user_id INTEGER NOT NULL,
+		expires_at DATETIME NOT NULL,
+		FOREIGN KEY(user_id) REFERENCES users(id)
+	);`
+	_, err = DB.Exec(sessionTable)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+// hash password
+func HashPassword(password string) (string, error) {
+	bytes, err := bcrypt.GenerateFromPassword([]byte(password), 14)
+	return string(bytes), err
+}
+
+// check password
+func CheckPasswordHash(password, hash string) bool {
+	err := bcrypt.CompareHashAndPassword([]byte(hash), []byte(password))
+	return err == nil
+}
+
+// create new user
+func CreateUser(username, password string) error {
+	hash, err := HashPassword(password)
+	if err != nil {
+		return err
+	}
+	_, err = DB.Exec("INSERT INTO users (username, password_hash) VALUES (?, ?)", username, hash)
+	return err
+}
+
+// get user by name
+func GetUserByUsername(username string) (*User, error) {
+	row := DB.QueryRow("SELECT id, username, password_hash FROM users WHERE username = ?", username)
+	u := &User{}
+	err := row.Scan(&u.ID, &u.Username, &u.PasswordHash)
+	if err != nil {
+		return nil, err
+	}
+	return u, nil
+}
+
+// create session token
+func CreateSession(userID int) (string, error) {
+	sessionID := uuid.New().String()
+	expiresAt := time.Now().Add(24 * time.Hour)
+
+	_, err := DB.Exec("INSERT INTO sessions (id, user_id, expires_at) VALUES (?, ?, ?)", sessionID, userID, expiresAt)
+	if err != nil {
+		return "", err
+	}
+	return sessionID, nil
+}
+
+// get user from session
+func GetUserFromSession(sessionID string) (*User, error) {
+	row := DB.QueryRow(`
+		SELECT u.id, u.username, u.password_hash
+		FROM users u
+		JOIN sessions s ON u.id = s.user_id
+		WHERE s.id = ? AND s.expires_at > ?
+	`, sessionID, time.Now())
+
+	u := &User{}
+	err := row.Scan(&u.ID, &u.Username, &u.PasswordHash)
+	if err != nil {
+		return nil, err
+	}
+	return u, nil
+}
+
+// delete session
+func DeleteSession(sessionID string) error {
+	_, err := DB.Exec("DELETE FROM sessions WHERE id = ?", sessionID)
+	return err
+}
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..7bc059f
--- /dev/null
+++ b/main.go
@@ -0,0 +1,166 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"html/template"
+	"log"
+	"net/http"
+	"path/filepath"
+	"time"
+
+	"sprintpadawan/lib"
+)
+
+type PingResponse struct {
+	Status  string `json:"status"`
+	Message string `json:"message"`
+}
+
+var templates *template.Template
+
+type contextKey string
+
+const userKey contextKey = "user"
+
+func main() {
+	lib.InitDB()
+
+	var err error
+	templates, err = template.ParseGlob(filepath.Join("templates", "*.html"))
+	if err != nil {
+		log.Fatalf("failed to parse templates: %v", err)
+	}
+
+	mux := http.NewServeMux()
+
+	// serve static assets
+	mux.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.Dir("static"))))
+
+	// public routes
+	mux.HandleFunc("/login", handleLogin)
+	mux.HandleFunc("/register", handleRegister)
+	mux.HandleFunc("/logout", handleLogout)
+
+	// private routes
+	mux.HandleFunc("/", requireAuth(handleIndex))
+	mux.HandleFunc("/api/ping", requireAuth(handlePing))
+	mux.HandleFunc("/api/ping-partial", requireAuth(handlePingPartial))
+
+	addr := ":8080"
+	log.Printf("Starting SprintPadawan server on http://localhost%s", addr)
+	if err := http.ListenAndServe(addr, mux); err != nil {
+		log.Fatalf("server error: %v", err)
+	}
+}
+
+func requireAuth(next http.HandlerFunc) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		cookie, err := r.Cookie("session_token")
+		if err != nil {
+			http.Redirect(w, r, "/login", http.StatusSeeOther)
+			return
+		}
+		user, err := lib.GetUserFromSession(cookie.Value)
+		if err != nil || user == nil {
+			http.Redirect(w, r, "/login", http.StatusSeeOther)
+			return
+		}
+		ctx := context.WithValue(r.Context(), userKey, user)
+		next.ServeHTTP(w, r.WithContext(ctx))
+	}
+}
+
+func handleLogin(w http.ResponseWriter, r *http.Request) {
+	if r.Method == http.MethodGet {
+		templates.ExecuteTemplate(w, "login.html", nil)
+		return
+	}
+
+	username := r.FormValue("username")
+	password := r.FormValue("password")
+
+	user, err := lib.GetUserByUsername(username)
+	if err != nil || !lib.CheckPasswordHash(password, user.PasswordHash) {
+		templates.ExecuteTemplate(w, "login.html", map[string]string{"Error": "Invalid credentials"})
+		return
+	}
+
+	sessionID, _ := lib.CreateSession(user.ID)
+	http.SetCookie(w, &http.Cookie{
+		Name:     "session_token",
+		Value:    sessionID,
+		Expires:  time.Now().Add(24 * time.Hour),
+		HttpOnly: true,
+		Path:     "/",
+	})
+
+	http.Redirect(w, r, "/", http.StatusSeeOther)
+}
+
+func handleRegister(w http.ResponseWriter, r *http.Request) {
+	if r.Method == http.MethodGet {
+		templates.ExecuteTemplate(w, "register.html", nil)
+		return
+	}
+
+	username := r.FormValue("username")
+	password := r.FormValue("password")
+	confirm := r.FormValue("confirm_password")
+
+	if password != confirm {
+		templates.ExecuteTemplate(w, "register.html", map[string]string{"Error": "Passwords do not match"})
+		return
+	}
+
+	err := lib.CreateUser(username, password)
+	if err != nil {
+		templates.ExecuteTemplate(w, "register.html", map[string]string{"Error": "Username taken"})
+		return
+	}
+
+	http.Redirect(w, r, "/login", http.StatusSeeOther)
+}
+
+func handleLogout(w http.ResponseWriter, r *http.Request) {
+	cookie, err := r.Cookie("session_token")
+	if err == nil {
+		lib.DeleteSession(cookie.Value)
+	}
+	http.SetCookie(w, &http.Cookie{
+		Name:    "session_token",
+		Value:   "",
+		Expires: time.Now().Add(-1 * time.Hour),
+		Path:    "/",
+	})
+	http.Redirect(w, r, "/login", http.StatusSeeOther)
+}
+
+func handleIndex(w http.ResponseWriter, r *http.Request) {
+	if r.URL.Path != "/" {
+		http.NotFound(w, r)
+		return
+	}
+	user := r.Context().Value(userKey).(*lib.User)
+	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	if err := templates.ExecuteTemplate(w, "index.html", user); err != nil {
+		log.Printf("template error: %v", err)
+		http.Error(w, "internal server error", http.StatusInternalServerError)
+	}
+}
+
+func handlePing(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+	resp := PingResponse{Status: "ok", Message: "pong"}
+	if err := json.NewEncoder(w).Encode(resp); err != nil {
+		log.Printf("json encode error: %v", err)
+	}
+}
+
+func handlePingPartial(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	if err := templates.ExecuteTemplate(w, "ping_result.html", PingResponse{Status: "ok", Message: "pong"}); err != nil {
+		log.Printf("template error: %v", err)
+		http.Error(w, "internal server error", http.StatusInternalServerError)
+	}
+}
diff --git a/static/styles/main.css b/static/styles/main.css
new file mode 100644
index 0000000..468d465
--- /dev/null
+++ b/static/styles/main.css
@@ -0,0 +1,873 @@
+/* reset */
+*,
+*::before,
+*::after {
+    box-sizing: border-box;
+    margin: 0;
+    padding: 0;
+}
+
+/* tokens */
+:root {
+    --bg: #0a0a0f;
+    --bg-surface: rgba(255, 255, 255, 0.04);
+    --bg-surface-hover: rgba(255, 255, 255, 0.07);
+    --border: rgba(255, 255, 255, 0.08);
+    --border-accent: rgba(139, 92, 246, 0.4);
+
+    --text-primary: #f1f5f9;
+    --text-secondary: #94a3b8;
+    --text-muted: #475569;
+
+    --accent: #8b5cf6;
+    --accent-hover: #7c3aed;
+    --accent-glow: rgba(139, 92, 246, 0.25);
+
+    --success-bg: rgba(16, 185, 129, 0.08);
+    --success-border: rgba(16, 185, 129, 0.25);
+    --success-text: #34d399;
+    --success-label: #6ee7b7;
+
+    --radius-sm: 6px;
+    --radius-md: 12px;
+    --radius-lg: 20px;
+
+    --shadow-card: 0 0 0 1px var(--border), 0 24px 48px rgba(0, 0, 0, 0.4);
+    --shadow-btn: 0 0 20px var(--accent-glow);
+
+    --font:
+        "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
+        sans-serif;
+    --font-mono:
+        "JetBrains Mono", "Fira Code", "Cascadia Code", ui-monospace, monospace;
+}
+
+/* base */
+html {
+    color-scheme: dark;
+}
+
+body {
+    font-family: var(--font);
+    background-color: var(--bg);
+    color: var(--text-primary);
+    min-height: 100vh;
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    padding: 2rem;
+    line-height: 1.6;
+
+    /* subtle grid bg */
+    background-image:
+        radial-gradient(
+            ellipse 80% 60% at 50% -10%,
+            rgba(139, 92, 246, 0.12),
+            transparent
+        ),
+        linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
+        linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
+    background-size:
+        auto,
+        40px 40px,
+        40px 40px;
+}
+
+/* card */
+.card {
+    background: var(--bg-surface);
+    border: 1px solid var(--border);
+    border-radius: var(--radius-lg);
+    box-shadow: var(--shadow-card);
+    padding: 3rem 2.75rem;
+    max-width: 480px;
+    width: 100%;
+    text-align: center;
+    backdrop-filter: blur(12px);
+    -webkit-backdrop-filter: blur(12px);
+    position: relative;
+    overflow: hidden;
+}
+
+/* app shell body — reset centering, fill viewport */
+body.app-body {
+    display: block;
+    padding: 0;
+    min-height: 100vh;
+    height: 100vh;
+    overflow: hidden;
+}
+
+/* top glow line */
+.card::before {
+    content: "";
+    position: absolute;
+    top: 0;
+    left: 10%;
+    right: 10%;
+    height: 1px;
+    background: linear-gradient(90deg, transparent, var(--accent), transparent);
+    opacity: 0.6;
+}
+
+/* logo / wordmark */
+.logo {
+    display: inline-flex;
+    align-items: center;
+    gap: 0.5rem;
+    margin-bottom: 1.25rem;
+}
+
+.logo-icon {
+    width: 36px;
+    height: 36px;
+    border-radius: var(--radius-sm);
+    background: linear-gradient(135deg, var(--accent), #6366f1);
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 1.1rem;
+    box-shadow: 0 0 16px var(--accent-glow);
+}
+
+/* heading */
+h1 {
+    font-size: 1.875rem;
+    font-weight: 700;
+    letter-spacing: -0.03em;
+    color: var(--text-primary);
+    line-height: 1.2;
+}
+
+h1 span {
+    background: linear-gradient(135deg, #c4b5fd, var(--accent));
+    -webkit-background-clip: text;
+    -webkit-text-fill-color: transparent;
+    background-clip: text;
+}
+
+.subtitle {
+    font-size: 0.9rem;
+    color: var(--text-secondary);
+    margin-top: 0.4rem;
+    margin-bottom: 2.25rem;
+}
+
+/* divider */
+.divider {
+    height: 1px;
+    background: var(--border);
+    margin: 2rem 0;
+}
+
+/* button */
+.ping-btn {
+    display: inline-flex;
+    align-items: center;
+    gap: 0.5rem;
+    background: linear-gradient(135deg, var(--accent), #6366f1);
+    color: #fff;
+    font-family: var(--font);
+    font-size: 0.9rem;
+    font-weight: 600;
+    padding: 0.65rem 1.6rem;
+    border: none;
+    border-radius: var(--radius-md);
+    cursor: pointer;
+    letter-spacing: 0.01em;
+    transition:
+        opacity 0.2s ease,
+        transform 0.15s ease,
+        box-shadow 0.2s ease;
+    box-shadow: var(--shadow-btn);
+    position: relative;
+    overflow: hidden;
+}
+
+.ping-btn::after {
+    content: "";
+    position: absolute;
+    inset: 0;
+    background: linear-gradient(rgba(255, 255, 255, 0.12), transparent);
+    pointer-events: none;
+}
+
+.ping-btn:hover {
+    opacity: 0.9;
+    box-shadow: 0 0 32px var(--accent-glow);
+    transform: translateY(-1px);
+}
+
+.ping-btn:active {
+    transform: scale(0.97) translateY(0);
+}
+
+.ping-btn.htmx-request {
+    opacity: 0.6;
+    cursor: wait;
+    transform: none;
+    box-shadow: none;
+}
+
+/* ping result area */
+#ping-result {
+    margin-top: 1.75rem;
+    min-height: 3rem;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+}
+
+/* result box */
+.result-box {
+    background: var(--success-bg);
+    border: 1px solid var(--success-border);
+    border-radius: var(--radius-md);
+    padding: 0.85rem 1.5rem;
+    width: 100%;
+    text-align: left;
+    display: flex;
+    align-items: center;
+    gap: 1rem;
+    animation: fadeSlideIn 0.25s ease forwards;
+}
+
+.result-dot {
+    width: 8px;
+    height: 8px;
+    border-radius: 50%;
+    background: var(--success-text);
+    box-shadow: 0 0 8px var(--success-text);
+    flex-shrink: 0;
+    animation: pulse 2s ease infinite;
+}
+
+.result-content {
+    display: flex;
+    flex-direction: column;
+    gap: 0.1rem;
+}
+
+.result-label {
+    font-size: 0.7rem;
+    font-weight: 700;
+    text-transform: uppercase;
+    letter-spacing: 0.08em;
+    color: var(--success-label);
+}
+
+.result-message {
+    font-family: var(--font-mono);
+    font-size: 0.9rem;
+    color: var(--success-text);
+}
+
+/* stats row */
+.stats {
+    display: flex;
+    gap: 1rem;
+    margin-top: 2rem;
+}
+
+.stat {
+    flex: 1;
+    background: var(--bg-surface);
+    border: 1px solid var(--border);
+    border-radius: var(--radius-md);
+    padding: 0.85rem 1rem;
+    transition:
+        background 0.2s ease,
+        border-color 0.2s ease;
+}
+
+.stat:hover {
+    background: var(--bg-surface-hover);
+    border-color: var(--border-accent);
+}
+
+.stat-value {
+    font-size: 1.25rem;
+    font-weight: 700;
+    color: var(--text-primary);
+    font-family: var(--font-mono);
+}
+
+.stat-label {
+    font-size: 0.75rem;
+    color: var(--text-muted);
+    margin-top: 0.1rem;
+}
+
+/* footer */
+footer {
+    margin-top: 2.5rem;
+    font-size: 0.78rem;
+    color: var(--text-muted);
+    display: flex;
+    align-items: center;
+    gap: 0.4rem;
+}
+
+footer a {
+    color: var(--text-secondary);
+    text-decoration: none;
+    transition: color 0.2s;
+}
+
+footer a:hover {
+    color: var(--accent);
+}
+
+/* animations */
+@keyframes fadeSlideIn {
+    from {
+        opacity: 0;
+        transform: translateY(6px);
+    }
+    to {
+        opacity: 1;
+        transform: translateY(0);
+    }
+}
+
+@keyframes pulse {
+    0%,
+    100% {
+        opacity: 1;
+    }
+    50% {
+        opacity: 0.4;
+    }
+}
+
+/* scrollbar */
+::-webkit-scrollbar {
+    width: 6px;
+}
+::-webkit-scrollbar-track {
+    background: transparent;
+}
+::-webkit-scrollbar-thumb {
+    background: var(--border);
+    border-radius: 99px;
+}
+
+/* ============================================================
+   AUTH PAGES (login / register)
+   ============================================================ */
+
+/* body variant — keeps the grid bg from body, just re-centers */
+.auth-body {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    min-height: 100vh;
+    padding: 2rem;
+}
+
+/* narrower card */
+.auth-card {
+    background: var(--bg-surface);
+    border: 1px solid var(--border);
+    border-radius: var(--radius-lg);
+    box-shadow: var(--shadow-card);
+    padding: 2.5rem 2.25rem;
+    max-width: 420px;
+    width: 100%;
+    text-align: center;
+    backdrop-filter: blur(12px);
+    -webkit-backdrop-filter: blur(12px);
+    position: relative;
+    overflow: hidden;
+}
+
+.auth-card::before {
+    content: "";
+    position: absolute;
+    top: 0;
+    left: 10%;
+    right: 10%;
+    height: 1px;
+    background: linear-gradient(90deg, transparent, var(--accent), transparent);
+    opacity: 0.6;
+}
+
+/* logo row */
+.auth-logo {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    gap: 0.5rem;
+    margin-bottom: 1.25rem;
+}
+
+/* headings */
+.auth-title {
+    font-size: 1.6rem;
+    font-weight: 700;
+    letter-spacing: -0.03em;
+    color: var(--text-primary);
+    line-height: 1.2;
+    margin-bottom: 0.35rem;
+}
+
+.auth-subtitle {
+    font-size: 0.875rem;
+    color: var(--text-secondary);
+    margin-bottom: 2rem;
+}
+
+/* form layout */
+.auth-form {
+    display: flex;
+    flex-direction: column;
+    gap: 1.25rem;
+    text-align: left;
+}
+
+.form-group {
+    display: flex;
+    flex-direction: column;
+    gap: 0.4rem;
+}
+
+.form-label {
+    font-size: 0.8rem;
+    font-weight: 600;
+    color: var(--text-secondary);
+    text-transform: uppercase;
+    letter-spacing: 0.07em;
+}
+
+.form-input {
+    width: 100%;
+    background: rgba(255, 255, 255, 0.05);
+    border: 1px solid var(--border);
+    border-radius: var(--radius-md);
+    padding: 0.7rem 1rem;
+    color: var(--text-primary);
+    font-family: var(--font);
+    font-size: 0.95rem;
+    transition:
+        border-color 0.2s ease,
+        box-shadow 0.2s ease;
+}
+
+.form-input::placeholder {
+    color: var(--text-muted);
+}
+
+.form-input:focus {
+    outline: none;
+    border-color: var(--accent);
+    box-shadow: 0 0 0 3px var(--accent-glow);
+}
+
+/* error message box */
+.form-error {
+    background: rgba(239, 68, 68, 0.08);
+    border: 1px solid rgba(239, 68, 68, 0.25);
+    border-radius: var(--radius-md);
+    padding: 0.7rem 1rem;
+    font-size: 0.85rem;
+    color: #f87171;
+    display: flex;
+    gap: 0.5rem;
+    align-items: center;
+}
+
+/* full-width primary button */
+.btn-primary {
+    width: 100%;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    gap: 0.5rem;
+    background: linear-gradient(135deg, var(--accent), #6366f1);
+    color: #fff;
+    font-family: var(--font);
+    font-size: 0.95rem;
+    font-weight: 600;
+    padding: 0.75rem;
+    border: none;
+    border-radius: var(--radius-md);
+    cursor: pointer;
+    letter-spacing: 0.01em;
+    transition:
+        opacity 0.2s ease,
+        transform 0.15s ease,
+        box-shadow 0.2s ease;
+    box-shadow: var(--shadow-btn);
+    position: relative;
+    overflow: hidden;
+}
+
+.btn-primary::after {
+    content: "";
+    position: absolute;
+    inset: 0;
+    background: linear-gradient(rgba(255, 255, 255, 0.12), transparent);
+    pointer-events: none;
+}
+
+.btn-primary:hover {
+    opacity: 0.9;
+    box-shadow: 0 0 32px var(--accent-glow);
+    transform: translateY(-1px);
+}
+
+.btn-primary:active {
+    transform: scale(0.97) translateY(0);
+}
+
+/* footer link line below the card */
+.auth-footer {
+    margin-top: 1.5rem;
+    font-size: 0.85rem;
+    color: var(--text-muted);
+    text-align: center;
+}
+
+.auth-footer a {
+    color: var(--accent);
+    text-decoration: none;
+    transition: opacity 0.2s;
+}
+
+.auth-footer a:hover {
+    opacity: 0.8;
+}
+
+/* "or" divider */
+.auth-divider {
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    color: var(--text-muted);
+    font-size: 0.8rem;
+}
+
+.auth-divider::before,
+.auth-divider::after {
+    content: "";
+    flex: 1;
+    height: 1px;
+    background: var(--border);
+}
+
+/* ============================================================
+   HOME / DASHBOARD — app shell
+   ============================================================ */
+
+.app-shell {
+    display: grid;
+    grid-template-columns: 240px 1fr;
+    grid-template-rows: 1fr;
+    height: 100vh;
+    width: 100%;
+    overflow: hidden;
+}
+
+/* sidebar */
+.sidebar {
+    background: rgba(255, 255, 255, 0.02);
+    border-right: 1px solid var(--border);
+    display: flex;
+    flex-direction: column;
+    padding: 1.5rem 1rem;
+    overflow-y: auto;
+}
+
+.sidebar-logo {
+    display: flex;
+    align-items: center;
+    gap: 0.6rem;
+    padding: 0.5rem 0.75rem;
+    margin-bottom: 1.5rem;
+}
+
+.sidebar-logo .logo-icon {
+    width: 36px;
+    height: 36px;
+    border-radius: var(--radius-sm);
+    background: linear-gradient(135deg, var(--accent), #6366f1);
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 1.1rem;
+    box-shadow: 0 0 16px var(--accent-glow);
+    flex-shrink: 0;
+}
+
+.sidebar-logo .logo-text {
+    font-weight: 700;
+    font-size: 1rem;
+    background: linear-gradient(135deg, #c4b5fd, var(--accent));
+    -webkit-background-clip: text;
+    -webkit-text-fill-color: transparent;
+    background-clip: text;
+}
+
+/* nav links */
+.sidebar-nav {
+    display: flex;
+    flex-direction: column;
+    gap: 0.25rem;
+    flex: 1;
+}
+
+.nav-item {
+    display: flex;
+    align-items: center;
+    gap: 0.65rem;
+    padding: 0.6rem 0.75rem;
+    border-radius: var(--radius-md);
+    color: var(--text-secondary);
+    text-decoration: none;
+    font-size: 0.9rem;
+    font-weight: 500;
+    transition: all 0.15s;
+    border: 1px solid transparent;
+}
+
+.nav-item:hover {
+    background: var(--bg-surface-hover);
+    color: var(--text-primary);
+}
+
+.nav-item.active {
+    background: rgba(139, 92, 246, 0.12);
+    color: var(--accent);
+    border-color: rgba(139, 92, 246, 0.2);
+}
+
+.nav-item svg {
+    width: 16px;
+    height: 16px;
+    flex-shrink: 0;
+}
+
+/* sidebar bottom section */
+.sidebar-footer {
+    margin-top: auto;
+    padding-top: 1rem;
+    border-top: 1px solid var(--border);
+}
+
+.user-row {
+    display: flex;
+    align-items: center;
+    gap: 0.65rem;
+    padding: 0.6rem 0.75rem;
+    border-radius: var(--radius-md);
+}
+
+.user-avatar {
+    width: 32px;
+    height: 32px;
+    border-radius: 50%;
+    background: linear-gradient(135deg, var(--accent), #6366f1);
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 0.8rem;
+    font-weight: 700;
+    color: #fff;
+    flex-shrink: 0;
+}
+
+.user-info {
+    display: flex;
+    flex-direction: column;
+    gap: 0.1rem;
+    overflow: hidden;
+    flex: 1;
+}
+
+.user-name {
+    font-size: 0.85rem;
+    font-weight: 600;
+    color: var(--text-primary);
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+}
+
+.user-role {
+    font-size: 0.72rem;
+    color: var(--text-muted);
+}
+
+.sign-out-btn {
+    width: 100%;
+    margin-top: 0.5rem;
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+    padding: 0.55rem 0.75rem;
+    border-radius: var(--radius-md);
+    background: transparent;
+    border: 1px solid var(--border);
+    color: var(--text-secondary);
+    font-size: 0.85rem;
+    font-family: var(--font);
+    cursor: pointer;
+    transition: all 0.15s;
+}
+
+.sign-out-btn:hover {
+    border-color: rgba(239, 68, 68, 0.4);
+    color: #f87171;
+    background: rgba(239, 68, 68, 0.06);
+}
+
+/* main content area */
+.main-content {
+    display: flex;
+    flex-direction: column;
+    overflow-y: auto;
+    background: var(--bg);
+}
+
+.topbar {
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    padding: 1.25rem 2rem;
+    border-bottom: 1px solid var(--border);
+    flex-shrink: 0;
+}
+
+.topbar-title {
+    font-size: 1rem;
+    font-weight: 600;
+    color: var(--text-primary);
+}
+
+.page-content {
+    padding: 2rem;
+    flex: 1;
+    max-width: 900px;
+    width: 100%;
+}
+
+/* welcome hero */
+.welcome-hero {
+    padding: 2rem;
+    background: var(--bg-surface);
+    border: 1px solid var(--border);
+    border-radius: var(--radius-lg);
+    margin-bottom: 2rem;
+    position: relative;
+    overflow: hidden;
+}
+
+.welcome-hero::before {
+    content: "";
+    position: absolute;
+    top: 0;
+    left: 10%;
+    right: 10%;
+    height: 1px;
+    background: linear-gradient(90deg, transparent, var(--accent), transparent);
+    opacity: 0.6;
+}
+
+.welcome-greeting {
+    font-size: 1.6rem;
+    font-weight: 700;
+    letter-spacing: -0.02em;
+    margin-bottom: 0.35rem;
+}
+
+.welcome-greeting span {
+    background: linear-gradient(135deg, #c4b5fd, var(--accent));
+    -webkit-background-clip: text;
+    -webkit-text-fill-color: transparent;
+    background-clip: text;
+}
+
+.welcome-sub {
+    color: var(--text-secondary);
+    font-size: 0.9rem;
+}
+
+/* dashboard stat cards grid */
+.dashboard-grid {
+    display: grid;
+    grid-template-columns: repeat(3, 1fr);
+    gap: 1rem;
+    margin-bottom: 2rem;
+}
+
+.dash-card {
+    background: var(--bg-surface);
+    border: 1px solid var(--border);
+    border-radius: var(--radius-lg);
+    box-shadow: var(--shadow-card);
+    backdrop-filter: blur(12px);
+    -webkit-backdrop-filter: blur(12px);
+    padding: 1.25rem 1.5rem;
+    text-align: left;
+    position: relative;
+    overflow: hidden;
+    transition:
+        background 0.2s ease,
+        border-color 0.2s ease;
+}
+
+.dash-card:hover {
+    background: var(--bg-surface-hover);
+    border-color: var(--border-accent);
+}
+
+.dash-card-label {
+    font-size: 0.72rem;
+    text-transform: uppercase;
+    letter-spacing: 0.08em;
+    color: var(--text-muted);
+    margin-bottom: 0.5rem;
+}
+
+.dash-card-value {
+    font-size: 1.5rem;
+    font-weight: 700;
+    font-family: var(--font-mono);
+    color: var(--text-primary);
+}
+
+/* ============================================================
+   RESPONSIVE
+   ============================================================ */
+
+@media (max-width: 768px) {
+    .app-shell {
+        grid-template-columns: 1fr;
+        grid-template-rows: auto 1fr;
+        height: auto;
+        min-height: 100vh;
+        overflow-y: auto;
+    }
+
+    .sidebar {
+        border-right: none;
+        border-bottom: 1px solid var(--border);
+        padding: 1rem;
+    }
+
+    .sidebar-nav {
+        flex-direction: row;
+        flex-wrap: wrap;
+        gap: 0.25rem;
+    }
+
+    .main-content {
+        overflow-y: unset;
+    }
+
+    .dashboard-grid {
+        grid-template-columns: 1fr;
+    }
+}
diff --git a/templates/index.html b/templates/index.html
new file mode 100644
index 0000000..e74bb2b
--- /dev/null
+++ b/templates/index.html
@@ -0,0 +1,150 @@
+<!doctype html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+        <title>Dashboard &mdash; SprintPadawan</title>
+        <link rel="preconnect" href="https://fonts.googleapis.com" />
+        <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
+        <link
+            href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap"
+            rel="stylesheet"
+        />
+        <link rel="stylesheet" href="/static/styles/main.css" />
+        <script src="https://unpkg.com/htmx.org@2.0.4" defer></script>
+    </head>
+    <body class="app-body">
+        <div class="app-shell">
+            <!-- sidebar -->
+            <aside class="sidebar">
+                <div class="sidebar-logo">
+                    <div class="logo-icon">⚡</div>
+                    <span class="logo-text"><span>Sprint</span>Padawan</span>
+                </div>
+
+                <nav class="sidebar-nav">
+                    <a href="/" class="nav-item active">
+                        <svg
+                            xmlns="http://www.w3.org/2000/svg"
+                            width="16"
+                            height="16"
+                            viewBox="0 0 24 24"
+                            fill="none"
+                            stroke="currentColor"
+                            stroke-width="2"
+                            stroke-linecap="round"
+                            stroke-linejoin="round"
+                        >
+                            <rect x="3" y="3" width="7" height="7" />
+                            <rect x="14" y="3" width="7" height="7" />
+                            <rect x="3" y="14" width="7" height="7" />
+                            <rect x="14" y="14" width="7" height="7" />
+                        </svg>
+                        Dashboard
+                    </a>
+                </nav>
+
+                <div class="sidebar-footer">
+                    <div class="user-row">
+                        <div class="user-avatar">{{slice .Username 0 1}}</div>
+                        <div class="user-info">
+                            <span class="user-name">{{.Username}}</span>
+                            <span class="user-role">Member</span>
+                        </div>
+                    </div>
+                    <form method="POST" action="/logout">
+                        <button class="sign-out-btn" type="submit">
+                            <svg
+                                xmlns="http://www.w3.org/2000/svg"
+                                width="14"
+                                height="14"
+                                viewBox="0 0 24 24"
+                                fill="none"
+                                stroke="currentColor"
+                                stroke-width="2.5"
+                                stroke-linecap="round"
+                                stroke-linejoin="round"
+                            >
+                                <path
+                                    d="M9 21H5a2 2 0 0 1-2-2V5a2 2 0 0 1 2-2h4"
+                                />
+                                <polyline points="16 17 21 12 16 7" />
+                                <line x1="21" y1="12" x2="9" y2="12" />
+                            </svg>
+                            Sign Out
+                        </button>
+                    </form>
+                </div>
+            </aside>
+
+            <!-- main -->
+            <div class="main-content">
+                <header class="topbar">
+                    <span class="topbar-title">Dashboard</span>
+                </header>
+
+                <main class="page-content">
+                    <!-- greeting -->
+                    <div class="welcome-hero">
+                        <p class="welcome-greeting">
+                            Welcome back, <span>{{.Username}}</span>
+                        </p>
+                        <p class="welcome-sub">
+                            Here's what's happening with your server.
+                        </p>
+                    </div>
+
+                    <!-- stat cards -->
+                    <div class="dashboard-grid">
+                        <div class="dash-card">
+                            <div class="dash-card-label">Runtime</div>
+                            <div class="dash-card-value">Go</div>
+                        </div>
+                        <div class="dash-card">
+                            <div class="dash-card-label">Reactivity</div>
+                            <div class="dash-card-value">HTMX</div>
+                        </div>
+                        <div class="dash-card">
+                            <div class="dash-card-label">Port</div>
+                            <div class="dash-card-value">:8080</div>
+                        </div>
+                    </div>
+
+                    <!-- ping section -->
+                    <div class="welcome-hero">
+                        <p class="welcome-greeting" style="font-size: 1.1rem">
+                            Server Health
+                        </p>
+                        <p class="welcome-sub" style="margin-bottom: 1.25rem">
+                            Ping the server to check it's alive.
+                        </p>
+
+                        <button
+                            class="ping-btn"
+                            hx-get="/api/ping-partial"
+                            hx-target="#ping-result"
+                            hx-swap="innerHTML"
+                        >
+                            <svg
+                                xmlns="http://www.w3.org/2000/svg"
+                                width="15"
+                                height="15"
+                                viewBox="0 0 24 24"
+                                fill="none"
+                                stroke="currentColor"
+                                stroke-width="2.5"
+                                stroke-linecap="round"
+                                stroke-linejoin="round"
+                            >
+                                <path d="M22 12h-4l-3 9L9 3l-3 9H2" />
+                            </svg>
+                            Ping Server
+                        </button>
+
+                        <div id="ping-result" style="margin-top: 1.25rem"></div>
+                    </div>
+                </main>
+            </div>
+        </div>
+    </body>
+</html>
diff --git a/templates/login.html b/templates/login.html
new file mode 100644
index 0000000..4391ffa
--- /dev/null
+++ b/templates/login.html
@@ -0,0 +1,80 @@
+<!doctype html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+        <title>Sign In &mdash; SprintPadawan</title>
+        <link rel="preconnect" href="https://fonts.googleapis.com" />
+        <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
+        <link
+            href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap"
+            rel="stylesheet"
+        />
+        <link rel="stylesheet" href="/static/styles/main.css" />
+    </head>
+    <body>
+        <div class="auth-card">
+            <div class="auth-logo">
+                <div class="logo-icon">⚡</div>
+            </div>
+
+            <h1 class="auth-title"><span>Sprint</span>Padawan</h1>
+            <p class="auth-subtitle">Sign in to your account</p>
+
+            {{if .Error}}
+            <div class="form-error">
+                <svg
+                    xmlns="http://www.w3.org/2000/svg"
+                    width="15"
+                    height="15"
+                    viewBox="0 0 24 24"
+                    fill="none"
+                    stroke="currentColor"
+                    stroke-width="2.5"
+                    stroke-linecap="round"
+                    stroke-linejoin="round"
+                >
+                    <circle cx="12" cy="12" r="10" />
+                    <line x1="12" y1="8" x2="12" y2="12" />
+                    <line x1="12" y1="16" x2="12.01" y2="16" />
+                </svg>
+                {{.Error}}
+            </div>
+            {{end}}
+
+            <form class="auth-form" method="POST" action="/login">
+                <div class="form-group">
+                    <label class="form-label" for="username">Username</label>
+                    <input
+                        class="form-input"
+                        type="text"
+                        id="username"
+                        name="username"
+                        placeholder="your username"
+                        autocomplete="username"
+                        required
+                    />
+                </div>
+
+                <div class="form-group">
+                    <label class="form-label" for="password">Password</label>
+                    <input
+                        class="form-input"
+                        type="password"
+                        id="password"
+                        name="password"
+                        placeholder="••••••••"
+                        autocomplete="current-password"
+                        required
+                    />
+                </div>
+
+                <button class="btn-primary" type="submit">Sign In</button>
+            </form>
+
+            <p class="auth-footer">
+                No account? <a href="/register">Create one</a>
+            </p>
+        </div>
+    </body>
+</html>
diff --git a/templates/ping_result.html b/templates/ping_result.html
new file mode 100644
index 0000000..f06b417
--- /dev/null
+++ b/templates/ping_result.html
@@ -0,0 +1,9 @@
+{{define "ping_result.html"}}
+<div class="result-box">
+    <div class="result-dot"></div>
+    <div class="result-content">
+        <span class="result-label">{{.Status}}</span>
+        <span class="result-message">{{.Message}}</span>
+    </div>
+</div>
+{{end}}
diff --git a/templates/register.html b/templates/register.html
new file mode 100644
index 0000000..e8ec340
--- /dev/null
+++ b/templates/register.html
@@ -0,0 +1,93 @@
+<!doctype html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+        <title>Register &mdash; SprintPadawan</title>
+        <link rel="preconnect" href="https://fonts.googleapis.com" />
+        <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
+        <link
+            href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap"
+            rel="stylesheet"
+        />
+        <link rel="stylesheet" href="/static/styles/main.css" />
+    </head>
+    <body>
+        <div class="auth-card">
+            <div class="auth-logo">
+                <div class="logo-icon">⚡</div>
+            </div>
+
+            <h1 class="auth-title"><span>Sprint</span>Padawan</h1>
+            <p class="auth-subtitle">Create your account</p>
+
+            {{if .Error}}
+            <div class="form-error">
+                <svg
+                    xmlns="http://www.w3.org/2000/svg"
+                    width="15"
+                    height="15"
+                    viewBox="0 0 24 24"
+                    fill="none"
+                    stroke="currentColor"
+                    stroke-width="2.5"
+                    stroke-linecap="round"
+                    stroke-linejoin="round"
+                >
+                    <circle cx="12" cy="12" r="10" />
+                    <line x1="12" y1="8" x2="12" y2="12" />
+                    <line x1="12" y1="16" x2="12.01" y2="16" />
+                </svg>
+                {{.Error}}
+            </div>
+            {{end}}
+
+            <form class="auth-form" method="POST" action="/register">
+                <div class="form-group">
+                    <label class="form-label" for="username">Username</label>
+                    <input
+                        class="form-input"
+                        type="text"
+                        id="username"
+                        name="username"
+                        placeholder="choose a username"
+                        autocomplete="username"
+                        required
+                    />
+                </div>
+
+                <div class="form-group">
+                    <label class="form-label" for="password">Password</label>
+                    <input
+                        class="form-input"
+                        type="password"
+                        id="password"
+                        name="password"
+                        placeholder="••••••••"
+                        autocomplete="new-password"
+                        required
+                    />
+                </div>
+
+                <div class="form-group">
+                    <label class="form-label" for="confirm_password">Confirm Password</label>
+                    <input
+                        class="form-input"
+                        type="password"
+                        id="confirm_password"
+                        name="confirm_password"
+                        placeholder="••••••••"
+                        autocomplete="new-password"
+                        required
+                    />
+                </div>
+
+                <button class="btn-primary" type="submit">Create Account</button>
+            </form>
+
+            <p class="auth-footer">
+                Already have an account? <a href="/login">Sign in</a>
+            </p>
+        </div>
+    </body>
+</html>