/* ============================================
   初中生学习考试系统 - 主样式表
   PC + 手机H5自适应
   ============================================ */

/* ---------- Reset & Base ---------- */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    --primary: #4A6CF7;
    --primary-dark: #3B5DE7;
    --success: #10B981;
    --warning: #F59E0B;
    --danger: #EF4444;
    --info: #3B82F6;
    --bg: #F0F2F5;
    --card-bg: #FFFFFF;
    --text: #1F2937;
    --text-secondary: #6B7280;
    --border: #E5E7EB;
    --radius: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
}

html { -webkit-text-size-adjust: 100%; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    font-size: 15px;
    line-height: 1.6;
    color: var(--text);
    background: var(--bg);
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------- App Layout ---------- */
.app-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ---------- Header ---------- */
.app-header {
    background: var(--primary);
    color: #fff;
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    height: 56px;
    gap: 24px;
}

.logo {
    color: #fff;
    font-size: 18px;
    font-weight: 700;
    white-space: nowrap;
}
.logo:hover { text-decoration: none; opacity: 0.9; }

/* 汉堡菜单按钮 - PC端隐藏 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 36px;
    height: 36px;
    padding: 6px;
    background: rgba(255,255,255,0.15);
    border: none;
    border-radius: 6px;
    cursor: pointer;
}
.menu-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background: #fff;
    border-radius: 2px;
    transition: all 0.3s;
}
.menu-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.menu-toggle.active span:nth-child(2) { opacity: 0; }
.menu-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

.main-nav {
    display: flex;
    gap: 4px;
    flex: 1;
}
.main-nav a {
    color: rgba(255,255,255,0.85);
    padding: 6px 14px;
    border-radius: 6px;
    font-size: 14px;
    transition: all 0.2s;
}
.main-nav a:hover {
    background: rgba(255,255,255,0.15);
    color: #fff;
    text-decoration: none;
}

/* 手机端导航中的用户区域 - PC端隐藏 */
.nav-user-mobile {
    display: none;
}

.user-info {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    white-space: nowrap;
}
.user-name-link {
    color: #fff;
    font-weight: 600;
}
.user-name-link:hover { text-decoration: underline; opacity: 0.9; }
.user-role { opacity: 0.8; font-size: 12px; color: #fff; }

.btn-logout {
    color: rgba(255,255,255,0.7);
    font-size: 13px;
    margin-left: 8px;
    padding: 4px 10px;
    border: 1px solid rgba(255,255,255,0.3);
    border-radius: 4px;
    transition: all 0.2s;
}
.btn-logout:hover {
    background: rgba(255,255,255,0.15);
    color: #fff;
    text-decoration: none;
}

/* ---------- Main Content ---------- */
.app-main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 24px 20px;
    flex: 1;
    width: 100%;
}

.app-footer {
    text-align: center;
    padding: 16px 20px;
    color: var(--text-secondary);
    font-size: 13px;
    border-top: 1px solid var(--border);
}

/* ---------- Flash Messages ---------- */
.flash {
    padding: 12px 16px;
    border-radius: var(--radius);
    margin-bottom: 16px;
    font-size: 14px;
}
.flash-success { background: #D1FAE5; color: #065F46; border: 1px solid #A7F3D0; }
.flash-error   { background: #FEE2E2; color: #991B1B; border: 1px solid #FECACA; }
.flash-info    { background: #DBEAFE; color: #1E40AF; border: 1px solid #BFDBFE; }

/* ---------- Auth Pages ---------- */
.auth-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 80vh;
    padding: 20px;
}

.auth-card {
    background: var(--card-bg);
    padding: 40px;
    border-radius: 12px;
    box-shadow: var(--shadow-md);
    width: 100%;
    max-width: 420px;
}

.auth-title {
    text-align: center;
    font-size: 24px;
    margin-bottom: 4px;
    color: var(--primary);
}
.auth-subtitle {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 24px;
    font-size: 14px;
}

.auth-form .form-group { margin-bottom: 18px; }
.auth-form label { 
    display: block; 
    margin-bottom: 6px; 
    font-weight: 500; 
    font-size: 14px;
}
.auth-form .required { color: var(--danger); }

.auth-footer {
    text-align: center;
    margin-top: 20px;
    font-size: 14px;
    color: var(--text-secondary);
}

/* ---------- Dashboard ---------- */
.stat-cards {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 24px;
}

.stat-card {
    background: var(--card-bg);
    padding: 24px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center;
}
.stat-icon { font-size: 32px; margin-bottom: 8px; }
.stat-value { font-size: 28px; font-weight: 700; color: var(--primary); }
.stat-label { font-size: 13px; color: var(--text-secondary); margin-top: 4px; }

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

.quick-actions {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

/* ---------- Cards ---------- */
.card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 24px;
}
.card-title {
    font-size: 17px;
    font-weight: 600;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--primary);
}

/* ---------- Buttons ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 8px 20px;
    border-radius: 6px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    border: 1px solid transparent;
    transition: all 0.2s;
    text-decoration: none;
    gap: 6px;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}
.btn:hover { text-decoration: none; }
.btn:active { transform: scale(0.97); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }

.btn-success { background: var(--success); color: #fff; }
.btn-success:hover { background: #059669; }

.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { background: #DC2626; }

.btn-outline {
    background: #fff;
    border-color: var(--border);
    color: var(--text);
}
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }

.btn-sm { padding: 4px 12px; font-size: 13px; }
.btn-lg { padding: 12px 28px; font-size: 16px; }
.btn-block { display: flex; width: 100%; }

.btn-group {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

/* ---------- Forms ---------- */
.form-group { margin-bottom: 16px; }
.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
    font-size: 14px;
}

.form-input, .form-select, .form-textarea {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 16px; /* 16px防止iOS自动缩放 */
    font-family: inherit;
    transition: border-color 0.2s;
    background: #fff;
    -webkit-appearance: none;
    appearance: none;
}
.form-select {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%236B7280' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 32px;
}
.form-input:focus, .form-select:focus, .form-textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(74,108,247,0.1);
}
.form-textarea { min-height: 100px; resize: vertical; }

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
}

.alert {
    padding: 12px 16px;
    border-radius: 6px;
    margin-bottom: 16px;
    font-size: 14px;
}
.alert-error { background: #FEE2E2; color: #991B1B; }
.alert-success { background: #D1FAE5; color: #065F46; }
.alert-info { background: #DBEAFE; color: #1E40AF; }
.alert-warning { background: #FEF3C7; color: #92400E; }

/* ---------- Tables ---------- */
.table {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
}
.table th, .table td {
    padding: 10px 12px;
    text-align: left;
    border-bottom: 1px solid var(--border);
}
.table th {
    background: #F9FAFB;
    font-weight: 600;
    font-size: 13px;
    color: var(--text-secondary);
    white-space: nowrap;
}
.table tr:hover td { background: #F9FAFB; }

/* ---------- Scores ---------- */
.score { font-weight: 700; }
.score-pass { color: var(--success); }
.score-fail { color: var(--danger); }

/* ---------- Subject Bars ---------- */
.subject-bars { display: flex; flex-direction: column; gap: 14px; }
.subject-bar-label {
    display: flex;
    justify-content: space-between;
    font-size: 14px;
    margin-bottom: 4px;
}
.subject-bar-track {
    height: 10px;
    background: #E5E7EB;
    border-radius: 5px;
    overflow: hidden;
}
.subject-bar-fill {
    height: 100%;
    border-radius: 5px;
    transition: width 0.6s ease;
}
.bar-pass { background: var(--success); }
.bar-fail { background: var(--danger); }

/* ---------- Empty State ---------- */
.empty-text {
    color: var(--text-secondary);
    text-align: center;
    padding: 40px 20px;
    font-size: 15px;
}

/* ---------- Exam Page ---------- */
.exam-container {
    max-width: 900px;
    margin: 0 auto;
}

.exam-header {
    background: var(--card-bg);
    padding: 16px 20px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
}

.exam-timer {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
}
.exam-timer.warning { color: var(--warning); }
.exam-timer.danger { color: var(--danger); animation: blink 1s infinite; }

@keyframes blink { 50% { opacity: 0.5; } }

.exam-progress {
    font-size: 14px;
    color: var(--text-secondary);
}

.question-card {
    background: var(--card-bg);
    padding: 20px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 12px;
}

.question-number {
    display: inline-block;
    background: var(--primary);
    color: #fff;
    width: 28px;
    height: 28px;
    line-height: 28px;
    text-align: center;
    border-radius: 50%;
    font-size: 13px;
    font-weight: 600;
    margin-right: 8px;
}

.question-type-badge {
    display: inline-block;
    padding: 2px 10px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
    margin-left: 8px;
}
.badge-single_choice { background: #DBEAFE; color: #1E40AF; }
.badge-single { background: #DBEAFE; color: #1E40AF; }
.badge-multi_choice  { background: #FEF3C7; color: #92400E; }
.badge-multi  { background: #FEF3C7; color: #92400E; }
.badge-true_false { background: #D1FAE5; color: #065F46; }
.badge-fill_blank { background: #EDE9FE; color: #5B21B6; }
.badge-fill   { background: #EDE9FE; color: #5B21B6; }
.badge-essay  { background: #FCE7F3; color: #9D174D; }

.question-content {
    margin: 12px 0;
    font-size: 16px;
    line-height: 1.8;
    word-break: break-word;
}

.question-options { margin-top: 12px; }
.option-item {
    display: flex;
    align-items: flex-start;
    padding: 12px 14px;
    margin-bottom: 8px;
    border: 2px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 15px;
    -webkit-tap-highlight-color: transparent;
}
.option-item:hover { border-color: var(--primary); background: #F0F4FF; }
.option-item.selected { border-color: var(--primary); background: #EEF2FF; }
.option-item:active { transform: scale(0.99); }

.option-item input[type="radio"],
.option-item input[type="checkbox"] {
    margin-right: 10px;
    margin-top: 3px;
    width: 20px;
    height: 20px;
    min-width: 20px;
    cursor: pointer;
}

.option-label {
    font-weight: 600;
    margin-right: 8px;
    min-width: 24px;
}

/* ---------- Exam Result ---------- */
.result-container {
    max-width: 900px;
    margin: 0 auto;
}

.result-header {
    background: linear-gradient(135deg, var(--primary), #6366F1);
    color: #fff;
    padding: 32px;
    border-radius: var(--radius);
    text-align: center;
    margin-bottom: 24px;
}
.result-score {
    font-size: 56px;
    font-weight: 800;
    margin: 12px 0;
}
.result-meta {
    display: flex;
    justify-content: center;
    gap: 24px;
    font-size: 14px;
    opacity: 0.9;
    flex-wrap: wrap;
}

.result-question {
    background: var(--card-bg);
    padding: 16px 20px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 12px;
    border-left: 4px solid var(--border);
}
.result-question.correct { border-left-color: var(--success); }
.result-question.wrong { border-left-color: var(--danger); }

.result-answer-info {
    margin-top: 10px;
    padding: 12px;
    background: #F9FAFB;
    border-radius: 6px;
    font-size: 14px;
}
.result-answer-info .your-answer { color: var(--danger); }
.result-answer-info .correct-answer { color: var(--success); font-weight: 600; }

.analysis-box {
    margin-top: 10px;
    padding: 14px;
    background: #FFFBEB;
    border: 1px solid #FDE68A;
    border-radius: 6px;
    font-size: 14px;
}
.analysis-box strong { color: #92400E; }

/* ---------- Pagination ---------- */
.pagination {
    display: flex;
    justify-content: center;
    gap: 4px;
    margin-top: 20px;
    flex-wrap: wrap;
}
.pagination a, .pagination span {
    display: inline-block;
    padding: 8px 14px;
    border: 1px solid var(--border);
    border-radius: 4px;
    font-size: 14px;
    color: var(--text);
    text-decoration: none;
    min-width: 40px;
    text-align: center;
}
.pagination a:hover { background: var(--primary); color: #fff; border-color: var(--primary); text-decoration: none; }
.pagination .active { background: var(--primary); color: #fff; border-color: var(--primary); }

/* ---------- Filter Bar ---------- */
.filter-bar {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    flex-wrap: wrap;
    align-items: center;
}
.filter-bar .form-select,
.filter-bar .form-input {
    width: auto;
    min-width: 130px;
}

/* ---------- Modal ---------- */
.modal-overlay {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0,0,0,0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 200;
    padding: 16px;
}
.modal {
    background: #fff;
    border-radius: 12px;
    padding: 28px;
    max-width: 600px;
    width: 100%;
    max-height: 85vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0,0,0,0.2);
    -webkit-overflow-scrolling: touch;
}
.modal-title {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 20px;
}
.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    margin-top: 24px;
}

/* ---------- Error Book ---------- */
.error-book-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    margin-bottom: 24px;
}

.mastered-badge {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 12px;
    font-weight: 500;
}
.mastered-yes { background: #D1FAE5; color: #065F46; }
.mastered-no  { background: #FEE2E2; color: #991B1B; }

/* ============================================
   手机H5适配 - 平板(≤768px)
   ============================================ */
@media (max-width: 768px) {
    /* 汉堡菜单显示 */
    .menu-toggle {
        display: flex;
        margin-left: auto;
    }

    /* PC端用户信息隐藏 */
    .user-info {
        display: none;
    }

    /* 导航改为下拉全屏覆盖 */
    .main-nav {
        display: none;
        position: fixed;
        top: 56px;
        left: 0;
        right: 0;
        bottom: 0;
        background: var(--primary);
        flex-direction: column;
        padding: 16px;
        gap: 4px;
        overflow-y: auto;
        z-index: 99;
        animation: slideDown 0.3s ease;
    }
    .main-nav.show {
        display: flex;
    }
    .main-nav a {
        padding: 14px 16px;
        font-size: 16px;
        border-radius: 8px;
    }
    .main-nav a:hover,
    .main-nav a:active {
        background: rgba(255,255,255,0.15);
    }

    /* 手机端导航用户区域显示 */
    .nav-user-mobile {
        display: flex;
        flex-direction: column;
        gap: 4px;
        border-top: 1px solid rgba(255,255,255,0.2);
        margin-top: 12px;
        padding-top: 12px;
    }
    .nav-user-mobile a {
        padding: 14px 16px;
        font-size: 16px;
        border-radius: 8px;
        color: rgba(255,255,255,0.85);
    }

    @keyframes slideDown {
        from { opacity: 0; transform: translateY(-10px); }
        to { opacity: 1; transform: translateY(0); }
    }

    /* Logo缩小 */
    .logo { font-size: 16px; }

    /* 主内容区 */
    .app-main { padding: 16px 12px; }

    /* 统计卡片 2列 */
    .stat-cards { grid-template-columns: repeat(2, 1fr); gap: 10px; }
    .stat-card { padding: 16px 12px; }
    .stat-value { font-size: 24px; }
    .stat-icon { font-size: 24px; }

    /* 错题统计 2列 */
    .error-book-stats { grid-template-columns: repeat(2, 1fr); gap: 10px; }

    /* 表单行单列 */
    .form-row { grid-template-columns: 1fr; gap: 12px; }

    /* 卡片 */
    .card { padding: 16px; }
    .card-title { font-size: 16px; }

    /* 按钮 */
    .btn { padding: 10px 16px; }
    .btn-lg { padding: 14px 24px; font-size: 16px; }
    .btn-sm { padding: 6px 12px; }

    /* 考试界面 */
    .exam-header { flex-direction: column; text-align: center; padding: 12px 16px; }
    .exam-timer { font-size: 24px; }
    .question-card { padding: 16px; }
    .question-content { font-size: 15px; }
    .option-item { padding: 12px; font-size: 14px; }
    .option-item input[type="radio"],
    .option-item input[type="checkbox"] { width: 22px; height: 22px; min-width: 22px; }

    /* 结果页 */
    .result-header { padding: 20px 16px; }
    .result-score { font-size: 40px; }
    .result-meta { gap: 12px; font-size: 13px; }
    .result-question { padding: 14px 16px; }

    /* 表格滚动 */
    .table-responsive { overflow-x: auto; -webkit-overflow-scrolling: touch; }
    .table th, .table td { padding: 8px 10px; font-size: 13px; }

    /* 筛选栏 */
    .filter-bar { gap: 8px; }
    .filter-bar .form-select,
    .filter-bar .form-input { min-width: 100px; font-size: 14px; }

    /* 弹窗 */
    .modal { padding: 20px; }
    .modal-title { font-size: 18px; }

    /* 快捷操作 */
    .quick-actions { flex-direction: column; }
    .quick-actions .btn { width: 100%; }

    /* 分页 */
    .pagination a, .pagination span { padding: 8px 10px; min-width: 36px; font-size: 13px; }

    /* 登录页 */
    .auth-card { padding: 24px 20px; margin: 10px; }
    .auth-title { font-size: 20px; }
}

/* ============================================
   手机H5适配 - 小屏手机(≤480px)
   ============================================ */
@media (max-width: 480px) {
    .stat-cards { grid-template-columns: 1fr; gap: 8px; }
    .stat-card { padding: 14px; flex-direction: row; display: flex; align-items: center; gap: 12px; }
    .stat-card .stat-icon { font-size: 28px; margin-bottom: 0; }
    .stat-card .stat-value { font-size: 22px; }

    .error-book-stats { grid-template-columns: 1fr; }

    .exam-timer { font-size: 22px; }
    .result-score { font-size: 36px; }

    .app-main { padding: 12px 10px; }
    .card { padding: 14px; border-radius: 6px; }

    .auth-card { padding: 20px 16px; }
    .auth-container { min-height: 70vh; }

    /* 表格紧凑 */
    .table th, .table td { padding: 6px 8px; font-size: 12px; }
}

/* ============================================
   安全区域适配 (iPhone刘海屏等)
   ============================================ */
@supports (padding: env(safe-area-inset-bottom)) {
    .app-footer {
        padding-bottom: calc(16px + env(safe-area-inset-bottom));
    }
    .main-nav {
        padding-bottom: env(safe-area-inset-bottom);
    }
}