@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

:root {
    /* 主题色系 */
    --primary-color: #005CB9; /* 主题蓝 */
    --primary-light: #4D94FF;
    --primary-dark: #00428A;
    --secondary-color: #E6F2FF; /* 柔和浅青蓝 */
    --accent-color: #00B4D8; /* 医疗青 / 强调色 */
    --text-color: #2C3E50;
    --text-light: #5C6E82;
    --border-color: #E2E8F0;
    --error-color: #FF4D4F;
    --success-color: #10B981;
    --warning-color: #F59E0B;
    
    /* 现代化UI视觉效果 (Glassmorphism & Shadows) */
    --bg-gradient: linear-gradient(135deg, #F0F4F8 0%, #E0EAF5 100%);
    --card-bg: rgba(255, 255, 255, 0.85);
    --card-border: rgba(255, 255, 255, 0.5);
    --shadow-sm: 0 4px 6px rgba(0, 92, 185, 0.05);
    --shadow-md: 0 10px 25px rgba(0, 92, 185, 0.1);
    --shadow-lg: 0 20px 40px rgba(0, 92, 185, 0.15);
}

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

html {
    /* 防止部分手机浏览器自动放大正文字号导致元素过大 */
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: var(--bg-gradient);
    background-attachment: fixed;
    color: var(--text-color);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* 登录页样式 */
.entry-body {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: url('data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSIxMDAlIiBoZWlnaHQ9IjEwMCUiPjxkZWZzPjxsaW5lYXJHcmFkaWVudCBpZD0iZyIgeDE9IjAlIiB5MT0iMCUiIHgyPSIxMDAlIiB5Mj0iMTAwJSI+PHN0b3Agb2Zmc2V0PSIwJSIgc3RvcC1jb2xvcj0iI0UxRkRGQyIvPjxzdG9wIG9mZnNldD0iMTAwJSIgc3RvcC1jb2xvcj0iI0Y0RjdGQiIvPjwvbGluZWFyR3JhZGllbnQ+PC9kZWZzPjxyZWN0IHdpZHRoPSIxMDAlIiBoZWlnaHQ9IjEwMCUiIGZpbGw9InVybCgjZykiLz48L3N2Zz4='), var(--bg-gradient);
    background-size: cover;
    position: relative;
}

.login-container {
    background: var(--card-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    padding: 2.5rem 2rem;
    border-radius: 16px;
    border: 1px solid var(--card-border);
    box-shadow: var(--shadow-lg);
    width: 90%;
    max-width: 420px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.login-container:hover {
    transform: translateY(-2px);
    box-shadow: 0 25px 50px rgba(0, 92, 185, 0.2);
}

.logo-area { text-align: center; margin-bottom: 2.5rem; }
.logo-area h1 { 
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-size: 1.8rem; 
    font-weight: 700;
    margin-bottom: 0.5rem;
}
.logo-area p { color: var(--text-light); font-size: 0.95rem; font-weight: 500; }

.form-group { margin-bottom: 1.5rem; }
.form-group label { display: block; margin-bottom: 0.6rem; font-weight: 600; font-size: 0.9rem; color: var(--text-color); }
.form-group input, .form-group select {
    width: 100%;
    padding: 12px 14px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    background-color: rgba(255, 255, 255, 0.9);
    transition: all 0.2s ease;
    outline: none;
}
.form-group input:focus, .form-group select:focus {
    border-color: var(--primary-light);
    box-shadow: 0 0 0 3px rgba(0, 92, 185, 0.1);
    background-color: #fff;
}

.exam-info {
    background: var(--secondary-color);
    padding: 1.2rem;
    border-radius: 8px;
    border-left: 4px solid var(--primary-color);
    margin: 1.5rem 0 2rem 0;
    font-size: 0.85rem;
    color: var(--text-dark);
}

.btn-primary {
    width: 100%;
    padding: 14px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-light) 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.05rem;
    cursor: pointer;
    font-weight: 600;
    letter-spacing: 0.5px;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}
.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 12px 20px rgba(0, 92, 185, 0.25);
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-color) 100%);
}

/* 考试页样式 */
.exam-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 64px;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 1.5rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    z-index: 100;
}

.timer-box { font-weight: 600; color: var(--primary-color); display: flex; align-items: center; gap: 6px; font-size: 1.05rem;}
.timer-box.warning { color: var(--error-color); animation: pulse 1s infinite alternate; }

.progress-box { flex: 1; margin: 0 2rem; text-align: center; font-size: 0.85rem; font-weight: 500; color: var(--text-light); }
.progress-bar { height: 8px; background: #e2e8f0; border-radius: 4px; margin-top: 6px; overflow: hidden; }
.progress-fill { height: 100%; background: linear-gradient(90deg, var(--accent-color), var(--primary-color)); border-radius: 4px; transition: width 0.4s cubic-bezier(0.4, 0, 0.2, 1); }

.btn-submit {
    background: transparent;
    border: 2px solid var(--primary-color);
    color: var(--primary-color);
    padding: 6px 18px;
    border-radius: 6px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}
.btn-submit:hover {
    background: var(--primary-color);
    color: white;
    box-shadow: var(--shadow-md);
}

.exam-container {
    margin-top: 80px;
    padding: 1rem;
    max-width: 850px;
    margin-left: auto;
    margin-right: auto;
    padding-bottom: 80px;
}

.question-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    min-height: 300px;
    transition: all 0.3s ease;
}

/* 多选题卡片样式 */
.question-card.multiple-question {
    background: linear-gradient(to bottom, rgba(230, 247, 255, 0.85) 0%, rgba(255, 255, 255, 0.85) 80px);
    border: 2px solid #b3e0ff;
}

/* 多选题提示 */
.multiple-tip {
    background: rgba(255, 255, 255, 0.7);
    border-left: 4px solid var(--accent-color);
    padding: 12px 14px;
    margin-bottom: 1.5rem;
    border-radius: 4px;
    font-size: 0.9rem;
    color: var(--primary-dark);
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 500;
}

.multiple-tip .tip-icon {
    font-size: 1.2rem;
    flex-shrink: 0;
}

.tag-row { display: flex; justify-content: space-between; margin-bottom: 1.2rem; font-size: 0.85rem; align-items: center; }
.tag-type { background: var(--secondary-color); color: var(--primary-color); padding: 4px 10px; border-radius: 6px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.5px;}
.tag-type.multiple { background: #E6F7FF; color: var(--accent-color); border: 1px solid #91D5FF; }
.tag-score { color: var(--text-light); font-weight: 500; font-size: 0.9rem; }

.question-text { font-size: 1.2rem; margin-bottom: 2rem; font-weight: 600; color: var(--text-color); line-height: 1.5; }

.option-item {
    display: flex;
    align-items: flex-start;
    padding: 14px 16px;
    border: 1px solid var(--border-color);
    background: #fff;
    border-radius: 8px;
    margin-bottom: 12px;
    cursor: pointer;
    font-size: 1.05rem;
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 1px 2px rgba(0,0,0,0.02);
}

.option-item:hover { 
    background-color: var(--secondary-color); 
    border-color: #A3D3FF;
    transform: translateX(4px);
}
.option-item.selected {
    background-color: var(--secondary-color);
    border-color: var(--primary-color);
    box-shadow: 0 0 0 1px var(--primary-color);
}

/* 多选题选项特殊样式 */
.option-item.option-multiple {
    border-width: 1px;
}

.option-item.option-multiple:hover {
    background-color: #E6F7FF;
    border-color: #91D5FF;
}

.option-item.option-multiple.selected {
    background-color: #e6f7ff;
    border-color: var(--primary-color);
    border-width: 2px;
}

.opt-label {
    width: 24px;
    height: 24px;
    background: #eee;
    display: flex;
    justify-content: center;
    align-items: center;
    margin-right: 12px;
    font-size: 0.8rem;
    flex-shrink: 0;
    transition: all 0.2s;
}

/* 单选题 - 圆形选择器 */
.opt-label-radio {
    border-radius: 50%;
}

/* 多选题 - 方形复选框 */
.opt-label-checkbox {
    border-radius: 4px;
    border: 2px solid #d9d9d9;
}

.option-item.selected .opt-label {
    background: var(--primary-color);
    color: white;
}

/* 多选题选中状态的额外样式 */
.option-multiple.selected .opt-label-checkbox {
    border-color: var(--primary-color);
    background: var(--primary-color);
    position: relative;
}

/* 多选题选中时显示勾选标记 */
.option-multiple.selected .opt-label-checkbox::after {
    content: '✓';
    position: absolute;
    color: white;
    font-weight: bold;
    font-size: 14px;
}

.nav-buttons {
    display: flex;
    justify-content: space-between;
    margin-top: 1.5rem;
}

.btn-nav {
    padding: 10px 24px;
    border: none;
    border-radius: 6px;
    background: #eee;
    cursor: pointer;
    font-size: 1rem;
}
.btn-nav:not(:disabled) { background: var(--primary-color); color: white; }
.btn-nav:disabled { opacity: 0.5; cursor: not-allowed; }

/* 答题卡网格 */
.answer-sheet { margin-top: 2rem; border-top: 1px solid #eee; padding-top: 1rem; }
.sheet-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(35px, 1fr)); gap: 8px; margin-top: 10px; }
.sheet-circle {
    width: 35px; height: 35px;
    border-radius: 50%;
    border: 1px solid #ddd;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 0.8rem;
    cursor: pointer;
}
.sheet-circle.active { background: var(--secondary-color); border-color: var(--primary-color); color: var(--primary-color); }
.sheet-circle.filled { background: var(--primary-color); color: white; border-color: var(--primary-color); }

@keyframes pulse { 0% { opacity: 1; } 50% { opacity: 0.5; } 100% { opacity: 1; } }

/* ==========================================
   移动端适配（≤480px）
   ========================================== */
@media (max-width: 480px) {
    /* 登录页：内容从顶部开始、可正常滚动，避免居中导致顶部被裁/按钮出屏 */
    .entry-body {
        align-items: flex-start;
        padding: 16px 12px calc(16px + env(safe-area-inset-bottom));
        min-height: 100vh;
    }
    .login-container {
        width: 100%;
        max-width: none;
        padding: 1.5rem 1.25rem;
        border-radius: 14px;
    }
    .login-container:hover { transform: none; } /* 移动端去掉悬浮位移 */

    .logo-area { margin-bottom: 1.25rem; }
    .logo-area h1 { font-size: 1.5rem; }
    .logo-area p { font-size: 0.9rem; }

    .form-group { margin-bottom: 1rem; }
    .form-group label { font-size: 0.95rem; margin-bottom: 0.4rem; }
    /* 输入字号 16px 可避免 iOS 聚焦时自动放大 */
    .form-group input, .form-group select { padding: 11px 12px; font-size: 16px; }

    .subtitle { font-size: 0.95rem; margin: 0.5rem 0; }
    .exam-info { padding: 0.9rem 1rem; margin: 1rem 0 1.25rem; font-size: 0.85rem; }
    .exam-info ul { padding-left: 1.1rem; }
    .btn-primary { padding: 13px; font-size: 1rem; }

    /* 答题页头部更紧凑 */
    .exam-header { height: 56px; padding: 0 12px; }
    .timer-box { font-size: 0.95rem; }
    .progress-box { margin: 0 10px; font-size: 0.75rem; }
    .btn-submit { padding: 6px 12px; font-size: 0.9rem; }

    /* 答题页正文 */
    .exam-container { margin-top: 68px; padding: 0.75rem; padding-bottom: 80px; }
    .question-card { padding: 1.1rem; min-height: auto; }
    .question-text { font-size: 1.05rem; margin-bottom: 1.25rem; }
    .option-item { padding: 12px 12px; font-size: 1rem; margin-bottom: 10px; }
    .option-item:hover { transform: none; } /* 移动端去掉位移，避免误触横移 */
    .multiple-tip { font-size: 0.82rem; padding: 10px 12px; margin-bottom: 1rem; }
    .btn-nav { padding: 10px 18px; font-size: 0.95rem; }
    .sheet-grid { grid-template-columns: repeat(auto-fill, minmax(32px, 1fr)); gap: 6px; }
    .sheet-circle { width: 32px; height: 32px; }
}