/* ========== 60句型英语学习平台 ========== */
:root {
    --primary: #4F46E5;
    --primary-light: #818CF8;
    --primary-dark: #3730A3;
    --success: #059669;
    --danger: #DC2626;
    --warning: #D97706;
    --bg: #F8FAFC;
    --surface: #FFFFFF;
    --text: #1E293B;
    --text-secondary: #64748B;
    --border: #E2E8F0;
    --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);
    --radius: 10px;
    --radius-sm: 6px;
    --transition: 0.2s ease;
}

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

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

/* ===== Layout ===== */
header {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 0 24px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

header .logo {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
}

header .logo span { color: var(--text-secondary); font-weight: 400; font-size: 14px; }

header nav { display: flex; gap: 4px; }

header nav a {
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    text-decoration: none;
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 500;
    transition: var(--transition);
}

header nav a:hover, header nav a.active {
    background: rgba(79,70,229,0.08);
    color: var(--primary);
}

header .user-info {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    color: var(--text-secondary);
}

header .user-info .role-badge {
    padding: 2px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.role-badge.teacher { background: #EDE9FE; color: var(--primary); }
.role-badge.student { background: #DCFCE7; color: var(--success); }

.container { max-width: 1200px; margin: 0 auto; padding: 24px; }

/* ===== Cards ===== */
.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
    margin-bottom: 16px;
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 16px;
}

.card-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--text);
}

.card-subtitle {
    font-size: 14px;
    color: var(--text-secondary);
    margin-top: 2px;
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 20px;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}

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

.btn-success { background: var(--success); color: #fff; }
.btn-success:hover { opacity: 0.9; }

.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { opacity: 0.9; }

.btn-outline {
    background: transparent;
    border: 1.5px solid var(--primary);
    color: var(--primary);
}
.btn-outline:hover { background: var(--primary); color: #fff; }

.btn-sm { padding: 6px 14px; font-size: 13px; }
.btn-lg { padding: 14px 28px; font-size: 16px; }

/* ===== Forms ===== */
.form-group { margin-bottom: 16px; }

.form-label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    color: var(--text);
    margin-bottom: 6px;
}

.form-input, .form-select, .form-textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    color: var(--text);
    background: var(--surface);
    transition: var(--transition);
    font-family: inherit;
}

.form-input:focus, .form-select:focus, .form-textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79,70,229,0.1);
}

.form-textarea { resize: vertical; min-height: 100px; }

/* ===== Tables ===== */
.table-wrap { overflow-x: auto; }

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
}

table th {
    background: #F1F5F9;
    padding: 12px 16px;
    text-align: left;
    font-weight: 600;
    color: var(--text-secondary);
    border-bottom: 2px solid var(--border);
}

table td {
    padding: 12px 16px;
    border-bottom: 1px solid var(--border);
}

table tr:hover { background: #F8FAFC; }

/* ===== Badges ===== */
.badge {
    display: inline-block;
    padding: 2px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.badge-blue { background: #DBEAFE; color: #1D4ED8; }
.badge-green { background: #DCFCE7; color: #059669; }
.badge-orange { background: #FED7AA; color: #C2410C; }
.badge-red { background: #FEE2E2; color: #991B1B; }
.badge-purple { background: #EDE9FE; color: #6D28D9; }

/* ===== Progress ===== */
.progress-bar {
    height: 8px;
    background: var(--border);
    border-radius: 4px;
    overflow: hidden;
    margin: 8px 0;
}

.progress-fill {
    height: 100%;
    border-radius: 4px;
    transition: width 0.5s ease;
}

.progress-fill.blue { background: var(--primary); }
.progress-fill.green { background: var(--success); }
.progress-fill.orange { background: var(--warning); }

/* ===== Stats Grid ===== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 24px;
}

.stat-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 20px;
    text-align: center;
    box-shadow: var(--shadow);
}

.stat-number {
    font-size: 36px;
    font-weight: 800;
    color: var(--primary);
    line-height: 1.2;
}

.stat-label {
    font-size: 14px;
    color: var(--text-secondary);
    margin-top: 4px;
}

/* ===== New Dashboard (modules / mainline) ===== */
.dash-header h1 { font-size: 22px; margin: 6px 0 2px; }
.dash-header p { color: var(--text-secondary); font-size: 14px; margin: 0 0 18px; }

.dash-modules {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 16px;
    margin-bottom: 8px;
}
.module-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 18px;
    box-shadow: var(--shadow);
    transition: transform .15s ease, box-shadow .15s ease;
    color: var(--text);
}
.module-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-lg); }
.module-icon { font-size: 30px; }
.module-title { font-weight: 700; font-size: 16px; margin: 6px 0 2px; }
.module-desc { font-size: 12px; color: var(--text-secondary); }

.dash-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 16px;
    margin: 8px 0 4px;
}
.stat-value { font-size: 32px; font-weight: 800; color: var(--primary); line-height: 1.2; }
.stat-suffix { font-size: 14px; font-weight: 600; color: var(--text-secondary); margin-left: 3px; }
.stat-label { font-size: 13px; color: var(--text-secondary); margin-top: 4px; }

.mainline {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
    gap: 16px;
}
.stage-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 16px;
    box-shadow: var(--shadow);
    text-decoration: none;
    color: var(--text);
    transition: transform .15s ease, box-shadow .15s ease;
}
.stage-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-lg); }
.stage-head { display: flex; align-items: center; justify-content: space-between; }
.stage-name { font-weight: 700; font-size: 15px; }
.stage-progress { display: flex; align-items: center; gap: 8px; margin-top: 10px; }
.stage-progress .progress-bar { flex: 1; margin: 0; }
.progress-text { font-size: 12px; color: var(--text-secondary); min-width: 34px; text-align: right; }
.stage-meta { margin-top: 6px; font-size: 13px; color: var(--text-secondary); }

/* 课程主线：与阶段路线对齐的三段式布局 */
.phase-block { margin: 18px 0; }
.phase-head { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
.phase-tag { font-size: 14px; font-weight: 800; padding: 3px 12px; border-radius: 999px; color: #fff; white-space: nowrap; }
.tag-main { background: #3b82f6; }
.tag-focus { background: #f59e0b; }
.tag-sprint { background: #ef4444; }
.tag-recite { background: #6366f1; }
.learn-btn { cursor: pointer; font-size: 12px; padding: 3px 10px; border-radius: 8px; border: 1px solid #8b5cf6; background: transparent; color: #8b5cf6; white-space: nowrap; }
.learn-btn.learned { background: #8b5cf6; color: #fff; border-color: #8b5cf6; }
.phase-desc { font-size: 13px; color: var(--text-secondary); }
.phase-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; }
.stage-card-recite { border-left: 4px solid #6366f1; background: linear-gradient(135deg, #eef2ff, #f8fafc); }

/* ===== Grid ===== */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }

@media (max-width: 768px) {
    .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
    .container { padding: 16px; }
}

/* ===== Lesson Content ===== */
.section-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--primary);
    margin: 24px 0 12px;
    padding-left: 12px;
    border-left: 4px solid var(--primary);
}

.pattern-display {
    background: linear-gradient(135deg, #EEF2FF, #E0E7FF);
    border: 1px solid #C7D2FE;
    border-radius: var(--radius);
    padding: 20px 24px;
    margin: 16px 0;
}

.pattern-formula {
    font-size: 22px;
    font-family: "Consolas", "Courier New", monospace;
    color: var(--primary-dark);
    font-weight: 700;
    margin-bottom: 12px;
}

.pattern-meaning {
    font-size: 15px;
    color: var(--text-secondary);
}

.example-sentence {
    padding: 10px 16px;
    background: #F0FDF4;
    border-left: 3px solid var(--success);
    margin: 8px 0;
    font-size: 15px;
}

.example-sentence .en { font-weight: 600; color: var(--text); }
.example-sentence .zh { color: var(--text-secondary); font-size: 13px; margin-top: 2px; }

/* ===== Exam Highlight ===== */
.exam-highlight {
    background: linear-gradient(135deg, #FFF7ED, #FFEDD5);
    border: 1px solid #FED7AA;
    border-radius: var(--radius);
    padding: 20px 24px;
    margin: 16px 0;
}

.exam-highlight .exam-meta {
    display: flex;
    gap: 12px;
    margin-bottom: 12px;
    flex-wrap: wrap;
}

.exam-highlight .exam-question {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 12px;
    padding: 12px;
    background: rgba(255,255,255,0.6);
    border-radius: var(--radius-sm);
}

.exam-highlight .analysis-box {
    background: white;
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    font-size: 14px;
    line-height: 1.8;
}

.exam-highlight .analysis-box .point {
    color: var(--primary);
    font-weight: 600;
}

/* ===== Question Block ===== */
.question-block {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 20px;
    margin: 12px 0;
    background: var(--surface);
}

.question-block .q-num {
    display: inline-block;
    width: 28px;
    height: 28px;
    background: var(--primary);
    color: white;
    text-align: center;
    line-height: 28px;
    border-radius: 50%;
    font-size: 13px;
    font-weight: 700;
    margin-bottom: 10px;
}

.question-block .q-stem {
    font-size: 15px;
    margin-bottom: 12px;
    line-height: 1.7;
}

.option-item {
    padding: 10px 16px;
    margin: 4px 0;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition);
    font-size: 14px;
}

.option-item:hover { border-color: var(--primary); background: #EEF2FF; }
.option-item.selected { border-color: var(--primary); background: #EEF2FF; font-weight: 600; }
.option-item.correct { border-color: var(--success); background: #DCFCE7; }
.option-item.wrong { border-color: var(--danger); background: #FEE2E2; }

/* ===== Cloze ===== */
.cloze-blank {
    display: inline-block;
    width: 100px;
    border-bottom: 2px solid var(--primary);
    margin: 0 8px;
    text-align: center;
    transition: var(--transition);
}

/* ===== Writing ===== */
.writing-area {
    width: 100%;
    min-height: 150px;
    padding: 16px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius);
    font-size: 15px;
    font-family: inherit;
    line-height: 1.8;
    resize: vertical;
}

.writing-area:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79,70,229,0.1);
}

/* ===== Review Panel ===== */
.review-panel .original {
    background: #F8FAFC;
    padding: 16px;
    border-radius: var(--radius-sm);
    white-space: pre-wrap;
    font-size: 14px;
    margin-bottom: 12px;
}

.review-panel textarea {
    width: 100%;
    padding: 12px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    resize: vertical;
}

.score-input {
    width: 80px;
    padding: 6px 10px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    text-align: center;
    font-size: 18px;
    font-weight: 700;
}

/* ===== Login ===== */
.login-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667EEA 0%, #764BA2 100%);
}

.login-card {
    background: white;
    border-radius: 16px;
    padding: 40px;
    width: 400px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.2);
}

.login-card h1 {
    text-align: center;
    margin-bottom: 8px;
    font-size: 24px;
    color: var(--text);
}

.login-card .subtitle {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 32px;
    font-size: 14px;
}

/* ===== Alerts ===== */
.alert {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    margin-bottom: 16px;
    font-size: 14px;
}

.alert-error { background: #FEE2E2; color: #991B1B; border: 1px solid #FECACA; }
.alert-success { background: #DCFCE7; color: #059669; border: 1px solid #BBF7D0; }
.alert-info { background: #DBEAFE; color: #1D4ED8; border: 1px solid #BFDBFE; }

/* ===== Tabs ===== */
.tabs { display: flex; gap: 4px; margin-bottom: 24px; border-bottom: 2px solid var(--border); }

.tab {
    padding: 10px 20px;
    border: none;
    background: none;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    transition: var(--transition);
}

.tab.active { color: var(--primary); border-bottom-color: var(--primary); }
.tab:hover { color: var(--primary); }

/* ===== Day Card in Dashboard ===== */
.day-card {
    display: block;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 16px;
    text-decoration: none;
    color: var(--text);
    transition: var(--transition);
}

.day-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
    transform: translateY(-1px);
}

.day-card .day-number {
    font-size: 28px;
    font-weight: 800;
    color: var(--primary);
}

.day-card .day-title { font-weight: 600; margin-top: 4px; }

.day-card .day-meta {
    font-size: 12px;
    color: var(--text-secondary);
    margin-top: 8px;
    display: flex;
    justify-content: space-between;
}

/* ===== Word list ===== */
.word-tag {
    display: inline-block;
    padding: 3px 10px;
    margin: 3px;
    border-radius: 20px;
    font-size: 13px;
    background: #EEF2FF;
    color: var(--primary-dark);
    cursor: pointer;
    transition: var(--transition);
}

.word-tag:hover { background: var(--primary); color: white; }

.word-tag.core { background: #FEE2E2; color: #991B1B; }
.word-tag.reading { background: #FED7AA; color: #C2410C; }
.word-tag.extended { background: #DCFCE7; color: #059669; }

/* ===== Submission status ===== */
.status-pending { color: var(--warning); }
.status-graded { color: var(--success); }

/* ===== Print optimization ===== */
@media print {
    header, nav, .btn { display: none; }
    .card { box-shadow: none; border: 1px solid #ddd; }
}

/* ===== Day Selector ===== */
.day-selector {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-bottom: 24px;
}

.day-selector a {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    text-decoration: none;
    font-weight: 600;
    font-size: 14px;
    border: 1.5px solid var(--border);
    color: var(--text-secondary);
    transition: var(--transition);
}

.day-selector a:hover, .day-selector a.active { background: var(--primary); border-color: var(--primary); color: white; }
.day-selector a.done { background: var(--success); border-color: var(--success); color: white; }

/* ===== 紧凑阶段天数布局 ===== */
.stage-days-compact {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 4px;
    row-gap: 6px;
}

.week-tag {
    display: inline-flex;
    align-items: center;
    height: 22px;
    padding: 0 8px;
    background: #e8f0fe;
    color: var(--primary);
    border-radius: 3px;
    font-size: 11px;
    font-weight: 600;
    margin-right: 2px;
    line-height: 1;
}

.day-chip {
    width: 34px;
    height: 34px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 500;
    text-decoration: none;
    background: var(--bg);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    transition: var(--transition);
    flex-shrink: 0;
}

.day-chip:hover { background: var(--primary); border-color: var(--primary); color: white; }
.day-chip.done { background: var(--success); border-color: var(--success); color: white; }

/* ===== Empty State ===== */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
}

.empty-state .icon { font-size: 48px; margin-bottom: 16px; }
.empty-state h3 { font-size: 18px; margin-bottom: 8px; color: var(--text); }