body {
    font-family: 'Segoe UI', Tahoma, sans-serif;
    background-color: #f5f7fa;
    margin: 0;
    padding: 0;
}

nav {
    padding: 1rem;
    display: flex;
    gap: 1rem;
}

nav a {
    color: white;
    text-decoration: none;
    font-weight: 500;
}

nav a:hover {
    text-decoration: underline;
}

.container {
    max-width: 600px;
    margin: 3rem auto;
    background-color: #fff;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 0 8px rgba(0,0,0,0.1);
}

h1, h2 {
    text-align: center;
    color: #2d3748;
}

form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

input[type="text"], input[type="email"], input[type="password"] {
    padding: 0.5rem;
    border: 1px solid #ccc;
    border-radius: 6px;
}

input[type="submit"], button, .btn {
    background-color: #3182ce;
    color: white;
    border: none;
    padding: 0.7rem;
    border-radius: 6px;
    cursor: pointer;
    font-weight: bold;
}

input[type="submit"]:hover {
    background-color: #2b6cb0;
}

.flash {
    padding: 10px;
    margin-bottom: 10px;
    border-radius: 4px;
    font-size: 0.9rem;
}

.flash.success { background-color: #c6f6d5; color: #22543d; }
.flash.info { background-color: #bee3f8; color: #2c5282; }
.flash.warning { background-color: #fefcbf; color: #744210; }
.flash.danger { background-color: #fed7d7; color: #742a2a; }