body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: linear-gradient(135deg, #0f172a, #1e293b);
    color: white;
}

.container {
    max-width: 600px;
    margin: auto;
    padding: 20px;
}

h1 {
    text-align: center;
}

.login-card, .submit-card {
    background: #1e293b;
    padding: 25px;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
    text-align: center;
}

input {
    width: 100%;
    padding: 12px;
    margin: 10px 0;
    border-radius: 10px;
    border: none;
}

button {
    width: 100%;
    padding: 12px;
    border: none;
    border-radius: 10px;
    background: #22c55e;
    color: white;
    font-size: 16px;
}

.nav {
    display: flex;
    justify-content: space-between;
    margin: 15px 0;
}

.btn {
    padding: 10px 15px;
    background: #38bdf8;
    border-radius: 10px;
    text-decoration: none;
    color: black;
}

.logout {
    background: #ef4444;
    color: white;
}

.links {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.card {
    background: #1e293b;
    padding: 15px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.4);
}

.card a {
    display: block;
    word-break: break-all;
    color: #38bdf8;
    margin-bottom: 10px;
}

.delete {
    color: #ef4444;
    font-size: 14px;
}

.back {
    display: inline-block;
    margin-top: 10px;
    color: #94a3b8;
}

.error {
    color: #ef4444;
}

.empty {
    text-align: center;
    color: #94a3b8;
}

@media (max-width: 600px) {
    .nav {
        flex-direction: column;
        gap: 10px;
    }
}