/* survey.css */
.survey-container {
    width: 100%;
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #ffffff;
    background-image: url("../images/background.png");
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    position: relative;
}

.progress-bar {
    position: absolute;
    top: 0;
    left: 0;
    height: 4px;
    background-color: #3498db;
    width: 0%;
    transition: width 0.4s ease;
}

.question-card {
    width: 800px;
    padding: 60px;
    background-color: rgba(255, 255, 255, 0.92);
    border: 1px solid #e0e6ed;
    box-shadow: 0 16px 38px rgba(44, 62, 80, 0.08);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    display: none; /* 默认隐藏 */
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.4s ease;
}

.question-card.active {
    display: block;
    opacity: 1;
    transform: translateY(0);
}

.question-number {
    font-size: 14px;
    color: #95a5a6;
    margin-bottom: 20px;
    letter-spacing: 1px;
}

.question-title {
    font-size: 28px;
    font-weight: 400;
    color: #2c3e50;
    line-height: 1.5;
    margin-bottom: 40px;
}

.answer-area {
    width: 100%;
}

.answer-input {
    width: 100%;
    padding: 15px 20px;
    font-size: 16px;
    border: 1px solid #bdc3c7;
    outline: none;
    resize: none;
    height: 120px;
    font-family: inherit;
    transition: border-color 0.3s ease;
}

.answer-input:focus {
    border-color: #3498db;
}

.controls {
    margin-top: 40px;
    display: flex;
    justify-content: space-between;
}

.btn {
    padding: 12px 30px;
    border: 1px solid #2c3e50;
    background-color: transparent;
    color: #2c3e50;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn:hover {
    background-color: #2c3e50;
    color: #ffffff;
}

.btn.disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.btn.disabled:hover {
    background-color: transparent;
    color: #2c3e50;
}

.btn-primary {
    background-color: #2c3e50;
    color: #ffffff;
}

.btn-primary:hover {
    background-color: #1a252f;
}

.home-link {
    position: absolute;
    top: 40px;
    left: 40px;
    font-size: 14px;
    color: #7f8c8d;
    cursor: pointer;
    border-bottom: 1px solid transparent;
    padding-bottom: 2px;
}

.home-link:hover {
    color: #2c3e50;
    border-bottom-color: #2c3e50;
}

/* 平板适配 */
@media screen and (max-width: 1024px) {
    .question-card {
        width: 90%;
        padding: 40px;
    }

    .question-title {
        font-size: 24px;
    }
}

/* 手机适配 */
@media screen and (max-width: 768px) {
    .survey-container {
        height: auto;
        min-height: 100vh;
        padding: 80px 0 40px;
        justify-content: flex-start;
    }

    .question-card {
        width: 92%;
        padding: 30px 25px;
    }

    .question-number {
        font-size: 12px;
        margin-bottom: 15px;
    }

    .question-title {
        font-size: 20px;
        line-height: 1.6;
        margin-bottom: 25px;
    }

    .answer-input {
        height: 100px;
        padding: 12px 15px;
        font-size: 15px;
    }

    .controls {
        margin-top: 25px;
        gap: 15px;
    }

    .btn {
        flex: 1;
        padding: 14px 20px;
        font-size: 14px;
    }

    .home-link {
        top: 20px;
        left: 20px;
        font-size: 13px;
    }
}

/* 小屏手机 */
@media screen and (max-width: 480px) {
    .question-card {
        width: 94%;
        padding: 25px 20px;
    }

    .question-title {
        font-size: 18px;
        margin-bottom: 20px;
    }

    .answer-input {
        height: 90px;
        font-size: 14px;
    }

    .controls {
        margin-top: 20px;
        flex-direction: column-reverse;
        gap: 12px;
    }

    .btn {
        width: 100%;
        padding: 16px;
        font-size: 15px;
    }

    .home-link {
        font-size: 12px;
    }
}