/* ---------- BASE ---------- */
body {
    font-family: Arial, Helvetica, sans-serif;
    background: linear-gradient(135deg, #667eea, #764ba2);
    margin: 0;
    padding: 0;
    color: #333;
    transition: all 0.3s ease;
}

.container {
    max-width: 900px;
    margin: 50px auto;
    background: #ffffff;
    padding: 30px;
    border-radius: 14px;
    box-shadow: 0 15px 35px rgba(0,0,0,0.2);
}

/* ---------- TOP BAR ---------- */
.top-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.toggle-btn {
    border: none;
    background: #eee;
    padding: 8px 14px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 16px;
}

/* ---------- TEXT ---------- */
.subtitle {
    text-align: center;
    color: #555;
    margin-bottom: 25px;
}

/* ---------- FORM ---------- */
form {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

input[type="text"] {
    flex: 1;
    padding: 12px;
    border-radius: 8px;
    border: 1px solid #ccc;
    font-size: 15px;
}

button {
    padding: 12px 22px;
    border: none;
    border-radius: 8px;
    background: #667eea;
    color: #fff;
    font-size: 15px;
    cursor: pointer;
}

button:hover {
    background: #5a67d8;
}

/* ---------- LOADER ---------- */
.loader {
    display: none;
    text-align: center;
    margin: 30px 0;
    font-weight: bold;
    color: #667eea;
}

.spinner {
    width: 42px;
    height: 42px;
    border: 4px solid #ddd;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    margin: 10px auto;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    100% { transform: rotate(360deg); }
}

/* ---------- OUTPUT ---------- */
.output {
    margin-top: 30px;
}

pre {
    background: #f7f7f7;
    padding: 20px;
    border-radius: 10px;
    white-space: pre-wrap;
    line-height: 1.7;
}

/* ---------- ERROR ---------- */
.error {
    color: red;
    font-weight: bold;
    margin-top: 15px;
}

/* ================= DARK MODE ================= */

body.dark {
    background: linear-gradient(135deg, #111827, #1f2933);
    color: #e5e7eb;
}

body.dark .container {
    background: #1f2933;
}

body.dark .subtitle {
    color: #9ca3af;
}

body.dark input[type="text"] {
    background: #111827;
    color: #e5e7eb;
    border: 1px solid #374151;
}

body.dark button {
    background: #2563eb;
}

body.dark button:hover {
    background: #1d4ed8;
}

body.dark .toggle-btn {
    background: #374151;
    color: #e5e7eb;
}

body.dark pre {
    background: #111827;
    color: #e5e7eb;
}

body.dark .spinner {
    border: 4px solid #374151;
    border-top: 4px solid #2563eb;
}