* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: #f5f5f5;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    background-color: #ffffff;
    width: 100%;
    max-width: 700px;
    padding: 40px;
    border: 8px solid;
    border-image: repeating-linear-gradient(-45deg,
            white 0,
            white 16px,
            white 16px,
            white 32px) 8;
}

h1 {
    font-size: 24px;
    font-weight: 600;
    color: #333;
    margin-bottom: 8px;
    text-align: center;
}

.subtitle {
    font-size: 14px;
    color: #666;
    text-align: center;
    margin-bottom: 30px;
}

.form-group {
    margin-bottom: 20px;
}

.intro {
    margin-bottom: 24px;
    padding: 16px 20px;
    background-color: #f8f8f8;
    border-left: 3px solid #333;
    font-size: 13px;
    line-height: 1.8;
    color: #555;
}

.intro p {
    margin-bottom: 8px;
}

.intro p:last-child {
    margin-bottom: 0;
}

.intro a {
    color: #333;
    text-decoration: underline;
    text-decoration-color: #ccc;
}

.intro a:hover {
    text-decoration-color: #333;
}

label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: #333;
    margin-bottom: 8px;
}

input[type="date"],
input[type="time"],
input[type="password"],
textarea {
    width: 100%;
    padding: 12px;
    font-size: 14px;
    border: 1px solid #ddd;
    background-color: #fff;
    color: #333;
}

input[type="date"]:focus,
input[type="time"]:focus,
textarea:focus {

    min-height: 80px;
    resize: vertical;
    font-family: inherit;
}

/* ===== 翻转卡片网格 ===== */
.type-selector {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 15px;
}

.type-option {
    position: relative;
    height: 140px;
    perspective: 1000px;
}

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

.card {
    position: relative;
    width: 100%;
    height: 100%;
    transform-style: preserve-3d;
    border: 2px solid transparent;
    transition: border-color 0.15s;
}

/* 选中时翻转 + 黑底 + 边框 */
.type-option input:checked~.card {
    transform: rotateY(180deg);
    border-color: #000;
}

.type-option input:checked~.card .card-front {
    background-color: #222;
    color: #fff;
}

.type-option input:checked~.card .card-front .card-front-number {
    background-color: #222;
    color: #fff;
    border-top-color: #444;
}

.type-option input:checked~.card .card-front .card-image {
    background-color: #222;
}

.card-front,
.card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border: 1px solid #ddd;
    display: flex;
    flex-direction: column;
}

.card-front {
    background-color: #fff;
    color: #333;
}

.card-image {
    flex: 1;
    background-color: #f8f8f8;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding: 15px;
    position: relative;
}

.card-image img {
    object-fit: cover;
    display: block;
}

.type-option input:checked~.card .card-image img {
    display: none;
}

.card-desc-overlay {
    display: none;
    font-size: 12px;
    line-height: 1.5;
    color: #ccc;
    text-align: center;
    padding: 10px;
}

.type-option input:checked~.card .card-image .card-desc-overlay {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    width: 100%;
}

.card-front-number {
    padding: 10px;
    text-align: center;
    font-size: 14px;
    font-weight: 600;
    background-color: #fff;
    border-top: 1px solid #eee;
}

/* ===== 卡片背面（翻转后显示） ===== */
.card-back {
    background-color: #333;
    color: #fff;
    transform: rotateY(180deg);
    padding: 15px;
    justify-content: center;
}

.card-back-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 8px;
}

.card-back-desc {
    font-size: 12px;
    line-height: 1.5;
    color: #ccc;
}

/* ===== 扩展字段样式 ===== */
.radio-group {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.radio-group label {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    font-weight: 500;
    padding: 7px 16px;
    border: 2px solid var(--c, #ddd);
    border-radius: 20px;
    background-color: #fff;
    cursor: pointer;
    transition: all 0.15s;
    margin: 0;
    color: #333;
}

.radio-group label:has(input:checked) {
    background-color: var(--c, #333);
    color: #fff;
    border-color: var(--c, #333);
}

.radio-group input[type="radio"] {
    -webkit-appearance: none;
    appearance: none;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    border: 2px solid var(--c, #ccc);
    background: #fff;
    cursor: pointer;
    flex-shrink: 0;
    transition: all 0.15s;
}

.radio-group input[type="radio"]:checked {
    background: var(--c, #333);
    border-color: var(--c, #333);
    box-shadow: inset 0 0 0 3px #fff;
}

.inline-options {
    display: flex;
    flex-wrap: wrap;
    gap: 6px 20px;
}

.inline-options label {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: 14px;
    font-weight: 400;
    cursor: pointer;
    margin: 0;
    color: #555;
}

.inline-options input[type="radio"] {
    accent-color: #333;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}

.feature-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 14px;
    background-color: #fafafa;
    border: 1px solid #eee;
    font-size: 13px;
    font-weight: 400;
    color: #333;
    cursor: pointer;
    margin: 0;
}

.feature-item .inline-radios {
    display: flex;
    gap: 10px;
    flex-shrink: 0;
}

.feature-item .inline-radios label {
    display: inline-flex;
    align-items: center;
    gap: 3px;
    font-size: 13px;
    font-weight: 400;
    cursor: pointer;
    margin: 0;
    color: #555;
}

.feature-item .inline-radios input[type="radio"] {
    accent-color: #333;
}

input[type="file"] {
    width: 100%;
    padding: 10px;
    font-size: 13px;
    border: 1px solid #ddd;
    background-color: #fafafa;
    color: #333;
    cursor: pointer;
}

input[type="file"]::file-selector-button {
    padding: 6px 16px;
    font-size: 13px;
    background-color: #333;
    color: #fff;
    border: none;
    cursor: pointer;
    margin-right: 10px;
}

/* 红色警告斑马线边框 */
body:has(input[name="color"][value="红色"]:checked) .container {
    border: 8px solid;
    border-image: repeating-linear-gradient(-45deg,
            #ff0000 0,
            #ff0000 16px,
            white 16px,
            white 32px) 8;
}

button {
    width: 100%;
    padding: 14px;
    font-size: 14px;
    font-weight: 500;
    background-color: #333;
    color: #fff;
    border: none;
    cursor: pointer;
}

button:hover {
    background-color: #000;
}

/* ===== 响应式 ===== */
@media (max-width: 540px) {
    body {
        padding: 10px;
    }

    .container {
        padding: 20px;
    }

    h1 {
        font-size: 20px;
    }

    .subtitle {
        font-size: 13px;
        margin-bottom: 20px;
    }

    .type-selector {
        grid-template-columns: repeat(3, 1fr);
        gap: 10px;
    }

    .type-option {
        height: 120px;
    }

    .card-front-number {
        font-size: 12px;
        padding: 8px;
    }

    .card-back {
        padding: 10px;
    }

    .card-back-title {
        font-size: 14px;
    }

    .card-back-desc {
        font-size: 11px;
    }

    .card-desc-overlay {
        font-size: 11px;
    }

    .datetime-row {
        gap: 8px;
    }

    input[type="date"],
    input[type="time"] {
        font-size: 13px;
        padding: 10px;
    }

    .record-item {
        padding: 12px;
        flex-wrap: wrap;
        gap: 8px;
    }

    .feature-item {
        padding: 8px 12px;
        font-size: 12px;
    }

    .feature-item .inline-radios {
        gap: 6px;
    }

    .features-grid {
        gap: 8px;
    }
}

@media (max-width: 400px) {
    .type-selector {
        grid-template-columns: repeat(2, 1fr);
        gap: 8px;
    }

    .type-option {
        height: 110px;
    }

    .container {
        padding: 14px;
    }

    h1 {
        font-size: 18px;
    }

    .datetime-row {
        flex-direction: column;
        gap: 8px;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .radio-group label {
        font-size: 12px;
        padding: 6px 13px;
    }
}