* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background: radial-gradient(circle at 60% 20%, #e0e7ff 0%, #f8fafc 55%, #dbeafe 100%);
    font-family: var(--font-sans);
    color: var(--text-main);
}

.page-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 48px 20px 64px;
}

.demo-card {
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    padding: 48px;
    border-radius: 20px;
    box-shadow: 0 20px 48px -12px rgba(15, 23, 42, 0.12);
    border: 1px solid rgba(255, 255, 255, 0.7);
    width: 100%;
    max-width: 760px;
}

.demo-header {
    margin-bottom: 36px;
}

h1 {
    font-size: 28px;
    font-weight: 800;
    margin: 0 0 8px 0;
    letter-spacing: -0.5px;
    color: var(--text-main);
}

.subtitle {
    color: var(--text-muted);
    font-size: 15px;
    margin: 0;
    font-weight: 500;
    line-height: 1.5;
}

.form-group {
    margin-bottom: 22px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

@media (max-width: 560px) {
    .form-row {
        grid-template-columns: 1fr;
    }
    .demo-card {
        padding: 32px 24px;
    }
}

label {
    display: block;
    font-size: 12px;
    font-weight: 700;
    margin-bottom: 7px;
    color: #475569;
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.required {
    color: #ef4444;
}

.optional {
    color: #94a3b8;
    font-weight: 500;
    text-transform: none;
    letter-spacing: 0;
    font-size: 11px;
}

input[type="text"],
textarea,
select {
    width: 100%;
    padding: 12px 14px;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    font-size: 15px;
    background: #ffffff;
    transition: border-color 0.2s, box-shadow 0.2s;
    font-family: var(--font-sans);
    color: var(--text-main);
}

textarea {
    resize: vertical;
}

input[type="text"]:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: var(--primary-blue);
    box-shadow: 0 0 0 3px rgba(48, 92, 222, 0.1);
}

select {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath fill='%23475569' d='M1 1l5 5 5-5'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 36px;
}

textarea {
    line-height: 1.55;
}

/* Radio buttons */
.radio-group {
    display: flex;
    gap: 12px;
}

.radio-option {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 3px;
    padding: 14px 16px;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    cursor: pointer;
    transition: border-color 0.2s, background 0.2s;
    text-transform: none;
    letter-spacing: 0;
    font-size: 14px;
    font-weight: 400;
    color: var(--text-main);
}

.radio-option:has(input:checked) {
    border-color: var(--primary-blue);
    background: #eff6ff;
}

.radio-option input[type="radio"] {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.radio-label {
    font-size: 14px;
    font-weight: 700;
    color: var(--text-main);
}

.radio-desc {
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 400;
}

/* Submit button */
.btn-create {
    width: 100%;
    padding: 15px;
    background: linear-gradient(135deg, var(--primary-blue) 0%, #1e3a8a 100%);
    color: #ffffff;
    border: none;
    border-radius: 10px;
    font-size: 15px;
    font-weight: 700;
    cursor: pointer;
    margin-top: 8px;
    transition: all 0.25s ease;
    box-shadow: 0 4px 14px rgba(48, 92, 222, 0.3);
    font-family: var(--font-sans);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.btn-create:hover:not(:disabled) {
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(48, 92, 222, 0.4);
    filter: brightness(1.07);
}

.btn-create:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

.spinner {
    width: 16px;
    height: 16px;
    border: 2px solid rgba(255, 255, 255, 0.4);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
    display: inline-block;
}

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

.hidden {
    display: none !important;
}

/* Result box */
.result-box {
    margin-top: 24px;
    padding: 20px 24px;
    border-radius: 12px;
    font-size: 14px;
    line-height: 1.6;
}

.result-success {
    background: #f0fdf4;
    border: 1px solid #bbf7d0;
    color: #14532d;
}

.result-error {
    background: #fef2f2;
    border: 1px solid #fca5a5;
    color: #7f1d1d;
}

.result-title {
    font-size: 15px;
    font-weight: 700;
    margin-bottom: 14px;
    color: #15803d;
}

.result-row {
    display: flex;
    align-items: baseline;
    gap: 10px;
    margin-bottom: 8px;
}

.result-label {
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: #16a34a;
    min-width: 96px;
}

.result-value {
    font-size: 14px;
    font-weight: 600;
    color: #14532d;
    word-break: break-all;
}

.result-id {
    font-family: 'Courier New', monospace;
    font-size: 13px;
}

.result-note {
    margin: 14px 0 0;
    font-size: 13px;
    color: #166534;
    opacity: 0.85;
}