:root {
    --primary-green: #7fda55;
    --primary-green-dark: #5cb536;
    --text-dark: #1a1a1a;
    --text-gray: #666666;
    --text-light: #999999;
    --bg-white: #ffffff;
    --bg-light: #f8f9fa;
    --border-dark: #1a1a1a;
    --border-light: #e0e0e0;
    --accent-blue: #4a90d9;
    --accent-red: #e74c3c;
    --accent-orange: #f39c12;
    --shadow-card: 4px 4px 0 #1a1a1a;
    --shadow-card-hover: 6px 6px 0 #1a1a1a;
    --shadow-button: 3px 3px 0 #1a1a1a;
    --shadow-button-hover: 4px 4px 0 #1a1a1a;
}

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
    scroll-padding-top: 100px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-white);
    color: var(--text-dark);
    min-height: 100vh;
    line-height: 1.7;
    overflow-x: hidden;
    visibility: visible;
    position: relative;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body.menu-open { 
    overflow: hidden; 
}

body.modal-open {
    overflow: hidden;
}

#page-content { 
    position: relative; 
    z-index: 1; 
}

/* ==================== 导航栏样式 ==================== */
.site-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    padding: 1rem 3rem;
    background: var(--bg-white);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-left {
    display: flex;
    align-items: center;
    gap: 3rem;
}

.nav-logo {
    font-size: 1.3rem;
    font-weight: 700;
    letter-spacing: 1px;
    color: var(--text-dark);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.nav-logo i { 
    color: var(--primary-green);
}

.nav-logo-icon {
    height: 2.2em;
    width: auto;
    vertical-align: middle;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-links a {
    color: var(--text-dark, #1a1a1a);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: color 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.4rem;
    position: relative;
}

.nav-links a:hover { 
    color: var(--text-dark, #1a1a1a); 
}

.nav-links a:hover::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-green, #7fda55);
    border-radius: 1px;
}

.nav-links a.active { 
    color: var(--text-dark, #1a1a1a);
    font-weight: 600;
    position: relative;
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-green, #7fda55);
    border-radius: 1px;
}

.nav-links a i { 
    font-size: 0.9rem; 
    color: var(--text-dark, #1a1a1a);
    transition: color 0.3s ease;
}

.nav-links a:hover i { 
    color: var(--primary-green, #7fda55);
}

.nav-links a.active i { 
    color: var(--primary-green, #7fda55);
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

/* 登录按钮样式 */
.btn-login {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.2rem;
    background: var(--primary-green);
    color: var(--text-dark);
    border: 2px solid var(--border-dark);
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9rem;
    transition: all 0.3s ease;
    box-shadow: 2px 2px 0 var(--border-dark);
    white-space: nowrap;
}

.btn-login:hover {
    background: var(--primary-green-dark);
    transform: translate(-2px, -2px);
    box-shadow: 4px 4px 0 var(--border-dark);
}

.btn-login i {
    font-size: 0.9rem;
}

/* 管理员信息样式 */
.admin-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.admin-name {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1rem;
    background: var(--bg-light);
    border: 2px solid var(--border-dark);
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--text-dark);
    white-space: nowrap;
}

.admin-name i {
    color: var(--primary-green);
}

/* 登出按钮样式 */
.btn-logout {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.2rem;
    background: var(--accent-red);
    color: white;
    border: 2px solid var(--border-dark);
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9rem;
    transition: all 0.3s ease;
    box-shadow: 2px 2px 0 var(--border-dark);
    white-space: nowrap;
}

.btn-logout:hover {
    background: #c0392b;
    transform: translate(-2px, -2px);
    box-shadow: 4px 4px 0 var(--border-dark);
}

.btn-logout i {
    font-size: 0.9rem;
}

/* 时间日期显示样式 */
.time-date-display {
    display: flex;
    align-items: center;
    background: var(--bg-light);
    border: 2px solid var(--border-dark);
    border-radius: 8px;
    padding: 0.6rem 1.2rem;
    width: 280px;
    transition: all 0.3s ease;
    box-shadow: 2px 2px 0 var(--border-dark);
    position: relative;
    color: var(--text-dark);
    font-size: 0.95rem;
    font-weight: 600;
}

.time-date-display:hover {
    background: var(--bg-white);
    box-shadow: 3px 3px 0 var(--border-dark);
    transform: translate(-1px, -1px);
}

.time-date-display i {
    color: var(--primary-green);
    margin-right: 0.5rem;
    font-size: 1rem;
}

.time-date-display span {
    flex: 1;
    text-align: center;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--text-dark);
}

/* 汉堡菜单按钮 */
.nav-hamburger {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    z-index: 1101;
    position: relative;
}

.nav-hamburger span {
    display: block;
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    transition: all 0.3s ease;
    border-radius: 2px;
}

.nav-hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(7px, 7px);
}

.nav-hamburger.active span:nth-child(2) {
    opacity: 0;
}

.nav-hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* 移动端导航菜单 */
.nav-mobile-menu {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: var(--bg-white);
    z-index: 900;
    padding-top: 80px;
    overflow-y: auto;
    transform: translateX(-100%);
    transition: transform 0.3s ease;
    -webkit-overflow-scrolling: touch;
}

.nav-mobile-menu.active {
    display: block;
    transform: translateX(0);
}

.nav-mobile-menu ul {
    list-style: none;
    padding: 2rem;
}

.nav-mobile-menu ul li {
    margin-bottom: 1.5rem;
}

.nav-mobile-menu ul li a {
    color: var(--text-dark);
    text-decoration: none;
    font-size: 1.2rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    border: 2px solid var(--border-dark);
    border-radius: 8px;
    background: var(--bg-light);
    transition: all 0.3s ease;
    box-shadow: 2px 2px 0 var(--border-dark);
}

.nav-mobile-menu ul li a:hover {
    transform: translate(-2px, -2px);
    box-shadow: 4px 4px 0 var(--border-dark);
    background: var(--primary-green);
    color: var(--text-dark);
}

.nav-mobile-menu ul li a i {
    font-size: 1.1rem;
    color: var(--text-gray);
    transition: color 0.3s ease;
}

.nav-mobile-menu ul li a:hover i {
    color: var(--text-dark);
}

/* ==================== 首页 Hero 模块 ==================== */
.hero { 
    min-height: 100vh; 
    display: flex; 
    align-items: center; 
    justify-content: center; 
    padding: 60px 0 40px; 
    position: relative; 
    overflow: hidden; 
}

#particle-canvas { 
    position: fixed; 
    top: 0; 
    left: 0; 
    width: 100vw; 
    height: 100vh; 
    z-index: 0; 
    pointer-events: none; 
}

.hero-content { 
    position: relative; 
    z-index: 1; 
    text-align: center; 
    max-width: 800px; 
}

.hero-badge { 
    display: inline-flex; 
    align-items: center; 
    gap: 0.6rem; 
    background: var(--bg-light); 
    border: 2px solid var(--border-dark); 
    border-radius: 24px; 
    padding: 0.55rem 1.4rem; 
    font-size: 0.95rem; 
    font-weight: 600; 
    margin: -0.25rem 0 2.2rem; 
    box-shadow: var(--shadow-card); 
    color: var(--text-dark);
}

.hero-badge i { 
    color: var(--primary-green);
}

.hero-title { 
    font-size: 4rem; 
    font-weight: 800; 
    letter-spacing: -0.02em; 
    margin-bottom: 2.05rem; 
    color: var(--text-dark); 
}

.text-box-a { 
    background: var(--bg-white); 
    border: 2px solid var(--border-dark); 
    padding: 1.2rem 1.4rem; 
    box-shadow: var(--shadow-card); 
    margin: 0 auto 2.25rem; 
    max-width: 720px; 
    color: var(--text-dark);
}

.text-box-a p {
    color: var(--text-dark);
    font-size: 1.1rem;
    line-height: 1.6;
}

.btn-primary { 
    background: var(--primary-green); 
    color: var(--text-dark); 
    border: 2px solid var(--border-dark); 
    padding: 0.9rem 2rem; 
    border-radius: 10px; 
    box-shadow: var(--shadow-button); 
    cursor: pointer; 
    font-size: 1rem; 
    font-weight: 700; 
    transition: all 0.3s ease; 
    text-decoration: none; 
    display: inline-flex; 
    align-items: center; 
    gap: 0.5rem; 
}

.btn-primary:hover { 
    transform: translate(-2px, -2px); 
    box-shadow: var(--shadow-button-hover); 
    background: var(--primary-green-dark);
}

.btn-primary i {
    color: var(--text-dark);
}

.btn-secondary { 
    background: var(--bg-white); 
    color: var(--text-dark); 
    border: 2px solid var(--border-dark); 
    padding: 0.9rem 2rem; 
    border-radius: 10px; 
    box-shadow: var(--shadow-button); 
    cursor: pointer; 
    font-size: 1rem; 
    font-weight: 700; 
    transition: all 0.3s ease; 
    text-decoration: none; 
    display: inline-flex; 
    align-items: center; 
    gap: 0.5rem; 
}

.btn-secondary:hover { 
    transform: translate(-2px, -2px); 
    box-shadow: var(--shadow-button-hover); 
    background: var(--bg-light); 
}

.btn-secondary i {
    color: var(--text-dark);
}

.hero-buttons { 
    display: flex; 
    flex-wrap: wrap; 
    gap: 1.2rem; 
    justify-content: center; 
    margin-top: 0.9rem; 
}

/* ==================== 点名程序样式 ==================== */

/* 左侧点名程序容器 */
.sidebar-notice {
    position: fixed;
    left: 0;
    top: 50%;
    transform: translateY(-50%) translateX(-100%);
    width: 320px;
    background: var(--bg-white);
    border: 2px solid var(--border-dark);
    box-shadow: var(--shadow-card);
    z-index: 1500;
    transition: transform 0.4s ease;
}
.sidebar-notice.active { 
    transform: translateY(-50%) translateX(0); 
}

.sidebar-notice-toggle {
    position: absolute;
    right: -45px;
    top: 50%;
    transform: translateY(-50%);
    width: 45px;
    height: 80px;
    background: var(--primary-green);
    border: 2px solid var(--border-dark);
    border-left: none;
    border-radius: 0 12px 12px 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--text-dark);
    transition: all 0.3s ease;
    box-shadow: 2px 2px 0 var(--border-dark);
}
.sidebar-notice-toggle:hover { 
    background: var(--primary-green-dark); 
}

.sidebar-notice-header {
    padding: 1.2rem 1.5rem;
    border-bottom: 2px solid var(--border-dark);
    display: flex;
    align-items: center;
    gap: 0.8rem;
    background: var(--bg-light);
}
.sidebar-notice-header i { 
    color: var(--primary-green);
    font-size: 1.2rem; 
}
.sidebar-notice.active .sidebar-notice-toggle i { 
    transform: rotate(180deg); 
}
.sidebar-notice-header h4 { 
    font-size: 1.1rem; 
    font-weight: 700; 
    color: var(--text-dark);
}

.sidebar-notice-body { 
    padding: 1.5rem; 
    max-height: 400px; 
    overflow-y: auto; 
    -webkit-overflow-scrolling: touch;
}

/* 班级选择 */
.class-selection {
    margin-bottom: 1.5rem;
}

.class-selection h5 {
    margin-bottom: 0.8rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    text-align: center;
}

.grade-selector {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.form-group label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-dark);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.3rem;
    text-align: center;
}

.form-select {
    padding: 0.5rem 0.8rem;
    border: 2px solid var(--border-dark);
    border-radius: 6px;
    background: var(--bg-white);
    color: var(--text-dark);
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 1px 1px 0 var(--border-dark);
    text-align: center;
    width: 100%;
}

.form-select:focus {
    outline: none;
    box-shadow: 2px 2px 0 var(--border-dark);
    transform: translate(-1px, -1px);
}

.form-select:disabled {
    background: var(--bg-light);
    cursor: not-allowed;
    opacity: 0.7;
}

/* 点名控制按钮 */
.roll-call-controls {
    display: flex;
    gap: 0.8rem;
    margin-bottom: 1.5rem;
    justify-content: center;
}

.btn-roll-call, .btn-reset {
    flex: 1;
    padding: 0.7rem;
    border: 2px solid var(--border-dark);
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    max-width: 140px;
}

.btn-roll-call {
    background: var(--primary-green);
    color: var(--text-dark);
    box-shadow: 2px 2px 0 var(--border-dark);
}

.btn-roll-call:hover:not(:disabled) {
    transform: translate(-2px, -2px);
    box-shadow: 3px 3px 0 var(--border-dark);
    background: var(--primary-green-dark);
}

.btn-roll-call:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    box-shadow: 2px 2px 0 var(--border-dark);
}

.btn-reset {
    background: var(--bg-white);
    color: var(--text-dark);
    box-shadow: 2px 2px 0 var(--border-dark);
}

.btn-reset:hover {
    transform: translate(-2px, -2px);
    box-shadow: 3px 3px 0 var(--border-dark);
    background: var(--bg-light);
}

/* 点名结果 */
.roll-call-result {
    margin-bottom: 0.5rem;
}

.roll-call-result h5 {
    margin-bottom: 0.8rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    text-align: center;
}

.result-display {
    background: var(--bg-light);
    border: 2px solid var(--border-dark);
    border-radius: 12px;
    padding: 1.5rem;
    min-height: 220px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 2px 2px 0 var(--border-dark);
    text-align: center;
}

.no-result {
    text-align: center;
    color: var(--text-light);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.no-result i {
    font-size: 2.5rem;
    margin-bottom: 0.8rem;
    opacity: 0.7;
}

.no-result p {
    font-size: 1rem;
    max-width: 200px;
}

/* 点名动画 */
.rolling-animation {
    text-align: center;
    color: var(--text-dark);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
}

.rolling-animation i {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--primary-green);
}

.rolling-text {
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--text-dark);
    text-align: center;
    min-height: 3rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* 最终结果 */
.final-result {
    width: 100%;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
}

.selected-student {
    padding: 1rem;
    background: linear-gradient(45deg, var(--primary-green), var(--primary-green-dark));
    border-radius: 12px;
    border: 4px solid var(--border-dark);
    box-shadow: 4px 4px 0 var(--border-dark);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    max-width: 280px;
    min-height: 150px;
}

.student-name-large {
    font-size: 3.5rem;
    font-weight: 900;
    color: var(--text-dark);
    line-height: 1.2;
    text-align: center;
    letter-spacing: 1px;
    text-shadow: 2px 2px 0 rgba(0, 0, 0, 0.1);
}

/* ==================== 每日一问弹窗样式 ==================== */
.daily-question-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    padding: 20px;
}

.daily-question-modal.active {
    opacity: 1;
    visibility: visible;
}

.daily-question-modal-content {
    background: var(--bg-white);
    border: 3px solid var(--border-dark);
    border-radius: 16px;
    width: 100%;
    max-width: 700px;
    box-shadow: 8px 8px 0 rgba(0, 0, 0, 0.3);
    transform: translateY(20px);
    transition: transform 0.3s ease;
    overflow: hidden;
}

.daily-question-modal.active .daily-question-modal-content {
    transform: translateY(0);
}

.daily-question-modal-header {
    padding: 1.5rem 2rem;
    border-bottom: 2px solid var(--border-dark);
    background: var(--bg-light);
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: relative;
}

.daily-question-modal-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    display: flex;
    align-items: center;
    gap: 0.8rem;
}

.daily-question-modal-header h3 i {
    color: var(--primary-green);
    font-size: 1.3rem;
}

.daily-question-close {
    background: var(--bg-white);
    border: 2px solid var(--border-dark);
    border-radius: 8px;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.2rem;
    color: var(--text-dark);
    transition: all 0.3s ease;
    box-shadow: 2px 2px 0 var(--border-dark);
}

.daily-question-close:hover {
    background: var(--primary-green);
    transform: translate(-2px, -2px);
    box-shadow: 4px 4px 0 var(--border-dark);
}

.daily-question-modal-body {
    padding: 2.5rem 2rem;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.question-content {
    font-size: 1.3rem;
    line-height: 1.8;
    color: var(--text-dark);
    text-align: center;
    width: 100%;
}

/* 修复LaTeX公式显示问题 */
.question-content .katex {
    font-size: 1.3rem !important;
    font-family: 'KaTeX_Main', 'Times New Roman', serif;
}

.question-content .katex-display {
    margin: 1rem 0;
    overflow-x: auto;
    overflow-y: hidden;
    padding: 0.5rem 0;
}

.question-content .katex-display > .katex {
    font-size: 1.3rem !important;
    text-align: center;
    display: block;
}

.question-content .katex-html {
    white-space: normal;
}

/* 内联公式样式 */
.question-content .katex-inline {
    font-size: 1.3rem;
    vertical-align: middle;
}

/* 确保文本和公式正确对齐 */
.question-content p {
    margin-bottom: 1rem;
    line-height: 1.8;
}

.question-content br {
    margin-bottom: 0.5rem;
    display: block;
    content: "";
}

.daily-question-modal-footer {
    padding: 1.5rem 2rem;
    border-top: 2px solid var(--border-dark);
    background: var(--bg-light);
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.daily-question-modal-footer button {
    min-width: 200px;
    padding: 0.9rem 2rem;
    font-size: 1.1rem;
    font-weight: 700;
}

/* ==================== Footer信息弹窗样式 ==================== */
.footer-info-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 2001;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    padding: 20px;
}

.footer-info-modal.active {
    opacity: 1;
    visibility: visible;
}

.footer-info-modal-content {
    background: var(--bg-white);
    border: 3px solid var(--border-dark);
    border-radius: 16px;
    width: 100%;
    max-width: 500px;
    box-shadow: 8px 8px 0 rgba(0, 0, 0, 0.3);
    transform: translateY(20px);
    transition: transform 0.3s ease;
    overflow: hidden;
}

.footer-info-modal.active .footer-info-modal-content {
    transform: translateY(0);
}

.footer-info-modal-header {
    padding: 1.5rem 2rem;
    border-bottom: 2px solid var(--border-dark);
    background: var(--bg-light);
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: relative;
}

.footer-info-modal-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    display: flex;
    align-items: center;
    gap: 0.8rem;
}

.footer-info-modal-header h3 i {
    color: var(--primary-green);
    font-size: 1.3rem;
}

.footer-info-close {
    background: var(--bg-white);
    border: 2px solid var(--border-dark);
    border-radius: 8px;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.2rem;
    color: var(--text-dark);
    transition: all 0.3s ease;
    box-shadow: 2px 2px 0 var(--border-dark);
}

.footer-info-close:hover {
    background: var(--primary-green);
    transform: translate(-2px, -2px);
    box-shadow: 4px 4px 0 var(--border-dark);
}

.footer-info-modal-body {
    padding: 2rem;
    min-height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.info-content {
    font-size: 1.2rem;
    line-height: 1.6;
    color: var(--text-dark);
    text-align: center;
    width: 100%;
    white-space: pre-line; /* 添加这行，保留换行符 */
}

.footer-info-modal-footer {
    padding: 1.5rem 2rem;
    border-top: 2px solid var(--border-dark);
    background: var(--bg-light);
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.footer-info-modal-footer button {
    min-width: 150px;
    padding: 0.8rem 1.5rem;
    font-size: 1rem;
    font-weight: 700;
}

/* ==================== Footer样式 ==================== */
footer { 
    background: var(--text-dark); 
    color: white; 
    padding: 4rem 0 2rem; 
    border-top: 4px solid var(--primary-green); 
    width: 100vw; 
    margin-left: calc(50% - 50vw); 
    margin-right: calc(50% - 50vw); 
    position: relative;
    z-index: 1;
}

footer .container { 
    width: 100%; 
    max-width: 1280px; 
    margin: 0 auto; 
    padding: 0 40px; 
}

.footer-content { 
    display: grid; 
    grid-template-columns: repeat(4, minmax(0, 1fr)); 
    gap: 6rem; 
    margin-bottom: 1rem; 
    margin-top: -0.5rem; 
    align-items: start; 
}

.footer-section h4 { 
    color: #fff; 
    font-size: 1.2rem; 
    margin-bottom: 1rem; 
    display: flex; 
    align-items: center; 
    gap: 0.5rem; 
}

.footer-section h4 i { 
    color: var(--primary-green); 
}

.footer-links { 
    list-style: none; 
    padding: 0; 
}

.footer-links li { 
    margin-bottom: 0.6rem; 
}

.footer-links a { 
    color: #aaa; 
    text-decoration: none; 
    font-size: 0.95rem; 
    transition: color 0.3s ease; 
    display: flex; 
    align-items: center; 
    gap: 0.5rem; 
}

.footer-links a:hover { 
    color: var(--primary-green); 
}

.footer-links a i { 
    font-size: 0.85rem; 
    width: 16px; 
}

.footer-bottom { 
    text-align: center; 
    padding-top: 2rem; 
    border-top: 1px solid #444; 
    color: #888; 
    font-size: 0.9rem; 
}

.footer-bottom a,
.footer-bottom a:visited,
.footer-bottom a:hover,
.footer-bottom a:active {
    color: inherit;
    text-decoration: none;
}

/* ==================== 响应式设计 ==================== */

/* 平板端 (768px - 1024px) */
@media (max-width: 1024px) {
    .site-nav {
        padding: 1rem 2rem;
    }
    
    .nav-left {
        gap: 2rem;
    }
    
    .nav-links {
        gap: 1.5rem;
    }
    
    .time-date-display {
        width: 220px;
        font-size: 0.85rem;
        padding: 0.5rem 1rem;
    }
    
    .hero-title {
        font-size: 3rem;
    }
    
    .student-name-large {
        font-size: 2.8rem;
    }
    
    .daily-question-modal-content {
        max-width: 600px;
    }
    
    .question-content {
        font-size: 1.2rem;
    }
    
    .question-content .katex {
        font-size: 1.2rem !important;
    }
    
    .footer-content {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

/* 手机端 (< 768px) */
@media (max-width: 768px) {
    html {
        scroll-padding-top: 150px;
    }
    
    .site-nav {
        padding: 0.8rem 1rem;
        flex-wrap: wrap;
    }
    
    .nav-left {
        width: 100%;
        justify-content: space-between;
        gap: 0;
        margin-bottom: 0.8rem;
    }
    
    .nav-logo {
        font-size: 1.1rem;
    }
    
    /* .nav-links 在移动端通过纯CSS控制显示/隐藏，不需要display: none */
    
    .nav-hamburger {
        display: flex;
    }
    
    /* .nav-mobile-menu 不再使用，可以移除或保留 */
    
    .nav-right {
        width: 100%;
        justify-content: flex-end;
        gap: 0.5rem;
        align-items: center;
    }
    
    .time-date-display {
        width: auto;
        max-width: 250px;
        padding: 0.5rem 0.8rem;
        font-size: 0.8rem;
        justify-content: center;
    }
    
    .hero {
        padding: 130px 20px 50px;
        min-height: auto;
    }
    
    .hero-content {
        max-width: 100%;
        padding: 0 10px;
    }
    
    .hero-badge {
        font-size: 0.85rem;
        padding: 0.4rem 1rem;
        margin-top: 0;
        margin-bottom: 1.5rem;
    }
    
    .hero-title {
        font-size: 2rem;
        margin-bottom: 1.5rem;
        line-height: 1.2;
    }
    
    .text-box-a {
        padding: 1rem;
        font-size: 0.9rem;
        max-width: 100%;
        margin: 0 auto 1.9rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        gap: 0.8rem;
        width: 100%;
        margin-top: 0.65rem;
    }
    
    .btn-primary,
    .btn-secondary {
        width: 100%;
        justify-content: center;
        padding: 0.74rem 1.5rem;
        font-size: 0.95rem;
    }
    
    .main-page {
        padding-top: 150px;
    }
    
    .sidebar-notice {
        width: 280px;
        max-width: 85vw;
    }
    
    .sidebar-notice-toggle {
        width: 40px;
        height: 70px;
        font-size: 1rem;
    }
    
    .sidebar-notice-header {
        padding: 1rem;
    }
    
    .sidebar-notice-header h4 {
        font-size: 1rem;
    }
    
    .sidebar-notice-body {
        padding: 1rem;
        max-height: 50vh;
    }
    
    .student-name-large {
        font-size: 2.2rem;
    }
    
    .rolling-text {
        font-size: 1.8rem;
    }
    
    .result-display {
        min-height: 180px;
        padding: 1rem;
    }
    
    .selected-student {
        min-height: 120px;
        max-width: 220px;
    }
    
    .daily-question-modal-content {
        max-width: 90%;
    }
    
    .daily-question-modal-header {
        padding: 1rem 1.5rem;
    }
    
    .daily-question-modal-header h3 {
        font-size: 1.2rem;
    }
    
    .daily-question-modal-body {
        padding: 1.5rem;
        min-height: 150px;
    }
    
    .question-content {
        font-size: 1.1rem;
    }
    
    .question-content .katex {
        font-size: 1.1rem !important;
    }
    
    .daily-question-modal-footer {
        padding: 1rem 1.5rem;
    }
    
    .daily-question-modal-footer button {
        min-width: auto;
        width: 100%;
        padding: 0.8rem 1.5rem;
        font-size: 1rem;
    }
    
    /* Footer信息弹窗响应式 */
    .footer-info-modal-content {
        max-width: 90%;
    }
    
    .footer-info-modal-header {
        padding: 1rem 1.5rem;
    }
    
    .footer-info-modal-header h3 {
        font-size: 1.2rem;
    }
    
    .footer-info-modal-body {
        padding: 1.5rem;
        min-height: 100px;
    }
    
    .info-content {
        font-size: 1.1rem;
    }
    
    .footer-info-modal-footer {
        padding: 1rem 1.5rem;
    }
    
    .footer-info-modal-footer button {
        min-width: auto;
        width: 100%;
        padding: 0.8rem 1.5rem;
        font-size: 1rem;
    }
    
    /* Footer响应式 */
    footer .container {
        padding: 0 20px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    /* 移动端汉堡菜单复选框（隐藏） */
    .mobile-menu-toggle {
        display: none !important;
        position: absolute !important;
        opacity: 0 !important;
        width: 0 !important;
        height: 0 !important;
        margin: 0 !important;
        padding: 0 !important;
        border: 0 !important;
        clip: rect(0, 0, 0, 0) !important;
        overflow: hidden !important;
        appearance: none !important;
        -webkit-appearance: none !important;
        -moz-appearance: none !important;
    }
    
    /* 移动端下拉菜单 - 纯CSS实现 */
    @media (max-width: 768px) {
        .nav-links {
            position: absolute;
            top: 100%;
            left: 0;
            width: 100%;
            background: var(--bg-white);
            border-top: 2px solid var(--border-dark);
            border-bottom: 2px solid var(--border-dark);
            flex-direction: column;
            padding: 1rem;
            gap: 0.5rem;
            transform: translateY(-100%);
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s ease;
            z-index: 1000;
            max-height: calc(100vh - 70px);
            overflow-y: auto;
            -webkit-overflow-scrolling: touch;
            box-shadow: 0 5px 15px rgba(0,0,0,0.1);
        }
        
        /* 当复选框被选中时显示菜单 */
        #mobile-menu-toggle:checked ~ .nav-links {
            transform: translateY(0);
            opacity: 1;
            visibility: visible;
        }
        
        /* 汉堡菜单按钮激活状态 */
        #mobile-menu-toggle:checked + .nav-hamburger span:nth-child(1) {
            transform: rotate(45deg) translate(7px, 7px);
        }
        
        #mobile-menu-toggle:checked + .nav-hamburger span:nth-child(2) {
            opacity: 0;
        }
        
        #mobile-menu-toggle:checked + .nav-hamburger span:nth-child(3) {
            transform: rotate(-45deg) translate(6px, -6px);
        }
        
        .nav-links li {
            width: 100%;
        }
        
        .nav-links a {
            width: 100%;
            padding: 1rem;
            border: 2px solid var(--border-dark);
            border-radius: 8px;
            justify-content: flex-start;
            font-size: 1.1rem;
            min-height: 50px;
            display: flex;
            align-items: center;
            background: var(--bg-light);
            transition: all 0.3s ease;
        }
        
        .nav-links a:hover {
            background: var(--primary-green);
            transform: translateY(-2px);
        }
        
        /* 当菜单打开时，禁止页面滚动 */
        #mobile-menu-toggle:checked ~ .nav-links {
            position: fixed;
            top: 70px;
            left: 0;
            height: calc(100vh - 70px);
        }
        
        body:has(#mobile-menu-toggle:checked) {
            overflow: hidden;
        }
    }
    
    .nav-hamburger {
        display: flex;
        margin-left: auto; /* 靠右对齐 */
        margin-right: 10px; /* 右边距 */
    }
    
    /* 汉堡菜单按钮在移动端增大点击区域 */
    .nav-hamburger {
        min-width: 44px;
        min-height: 44px;
        justify-content: center;
        align-items: center;
    }
    
    .hero {
        padding-top: 120px;
        padding-bottom: 40px;
    }
}

/* 小屏幕手机端 (< 480px) */
@media (max-width: 480px) {
    .hero-title {
        font-size: 1.6rem;
    }
    
    .site-nav {
        padding: 0.6rem 0.8rem;
    }
    
    .nav-logo {
        font-size: 1rem;
    }
    
    /* 在移动端隐藏时间显示，避免与下拉菜单重叠 */
    .time-date-display {
        display: none !important;
    }
    
    /* 调整导航栏布局，为汉堡菜单腾出空间 */
    .nav-right {
        display: none; /* 隐藏整个右侧区域（包含时间显示） */
    }
    
    .nav-left {
        width: 100%;
        justify-content: space-between;
    }
    
    .nav-hamburger {
        margin-left: 0; /* 重置左边距 */
        order: 2; /* 汉堡菜单放在最右边 */
    }
    
    .nav-logo {
        order: 1; /* Logo放在左边 */
    }
    
    .student-name-large {
        font-size: 2.2rem;
    }
    
    .rolling-text {
        font-size: 1.5rem;
    }
    
    .result-display {
        min-height: 150px;
    }
    
    .selected-student {
        min-height: 100px;
        max-width: 180px;
    }
    
    .daily-question-modal-content {
        max-width: 95%;
    }
    
    .daily-question-modal-header {
        padding: 0.8rem 1rem;
    }
    
    .daily-question-modal-header h3 {
        font-size: 1.1rem;
    }
    
    .daily-question-modal-body {
        padding: 1rem;
        min-height: 120px;
    }
    
    .question-content {
        font-size: 1rem;
        line-height: 1.6;
    }
    
    .question-content .katex {
        font-size: 1rem !important;
    }
    
    .daily-question-close {
        width: 35px;
        height: 35px;
        font-size: 1rem;
    }
    
    .daily-question-modal-footer button {
        padding: 0.7rem 1.2rem;
        font-size: 0.95rem;
    }
    
    /* Footer信息弹窗 */
    .footer-info-modal-content {
        max-width: 95%;
    }
    
    .footer-info-modal-header {
        padding: 0.8rem 1rem;
    }
    
    .footer-info-modal-header h3 {
        font-size: 1.1rem;
    }
    
    .footer-info-modal-body {
        padding: 1rem;
        min-height: 80px;
    }
    
    .info-content {
        font-size: 1rem;
    }
    
    .footer-info-close {
        width: 35px;
        height: 35px;
        font-size: 1rem;
    }
    
    .footer-info-modal-footer button {
        padding: 0.7rem 1.2rem;
        font-size: 0.95rem;
    }
    
    /* Footer */
    footer {
        padding: 3rem 0 1.5rem;
    }
    
    footer .container {
        padding: 0 15px;
    }
    
    .footer-content {
        gap: 1.5rem;
        margin-bottom: 2rem;
    }
    
    .footer-section h4 {
        font-size: 1.1rem;
    }
    
    .footer-links a {
        font-size: 0.9rem;
    }
    
    .footer-bottom {
        font-size: 0.8rem;
        padding-top: 1.5rem;
    }
    
    /* 确保侧边栏在移动端显示正常 */
    .sidebar-notice {
        width: 280px;
    }
    
    .sidebar-notice-toggle {
        right: -40px;
        width: 40px;
    }
}

/* 超小屏幕手机端 (< 375px) */
@media (max-width: 375px) {
    .hero-title {
        font-size: 1.4rem;
    }
    
    .text-box-a {
        padding: 0.8rem;
    }
    
    .text-box-a p {
        font-size: 0.85rem;
    }
    
    .hero-badge {
        font-size: 0.8rem;
        padding: 0.3rem 0.8rem;
    }
    
    .nav-logo {
        font-size: 0.9rem;
    }
    
    .time-date-display {
        max-width: 140px;
        font-size: 0.65rem;
    }
    
    .footer-section h4 {
        font-size: 1rem;
    }
    
    .footer-links a {
        font-size: 0.85rem;
    }
}