/* ========================================
   学伴星 - 主样式表
   温馨、简洁、现代的设计风格
   ======================================== */

:root {
    /* 温馨的蓝色配色方案 */
    --primary-color: #5B9BD5;
    --primary-light: #8BBDE9;
    --primary-dark: #3A7BC8;

    --secondary-color: #6BC4D8;
    --secondary-light: #95DAEA;
    --secondary-dark: #48B0C7;

    --accent-green: #7ECC9D;
    --accent-pink: #F0A0B0;
    --accent-yellow: #FFE082;
    --accent-purple: #B8A0D8;

    /* 中性色 */
    --bg-primary: #F5F9FC;
    --bg-secondary: #FFFFFF;
    --bg-tertiary: #EEF4FA;
    --text-primary: #2C3E50;
    --text-secondary: #5A6B7D;
    --text-muted: #8E9AAF;
    --border-color: #D8E5F0;

    /* 状态色 */
    --success: #81C784;
    --warning: #FFB74D;
    --error: #E57373;
    --info: #64B5F6;

    /* 间距和圆角 */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-xxl: 48px;

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 50%;

    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(91, 155, 213, 0.08);
    --shadow-md: 0 4px 16px rgba(91, 155, 213, 0.12);
    --shadow-lg: 0 8px 32px rgba(91, 155, 213, 0.16);
    --shadow-hover: 0 12px 40px rgba(91, 155, 213, 0.2);

    /* 过渡动画 */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.25s ease;
    --transition-slow: 0.4s ease;

    /* 字体 */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
}

/* 重置和基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-family);
    background: linear-gradient(135deg, var(--bg-primary) 0%, #E0EEF8 100%);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* 应用容器 */
.app-container {
    display: flex;
    min-height: 100vh;
}

/* ========================================
   侧边导航栏
   ======================================== */
.sidebar {
    width: 240px;
    background: var(--bg-secondary);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    padding: var(--spacing-lg) 0;
    position: fixed;
    height: 100vh;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: 0 var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.logo-icon {
    font-size: 32px;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-5px); }
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary-color);
    letter-spacing: 0.5px;
}

.nav-menu {
    list-style: none;
    flex: 1;
    padding: 0 var(--spacing-md);
}

.nav-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
    margin-bottom: var(--spacing-xs);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-normal);
    color: var(--text-secondary);
    font-weight: 500;
}

.nav-item:hover {
    background: var(--bg-tertiary);
    color: var(--primary-color);
    transform: translateX(4px);
}

.nav-item.active {
    background: linear-gradient(135deg, var(--primary-light), var(--primary-color));
    color: white;
    box-shadow: var(--shadow-md);
}

.nav-icon {
    font-size: 20px;
}

.sidebar-footer {
    padding: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
}

.user-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.user-avatar-small {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    background: var(--accent-yellow);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
}

/* ========================================
   主内容区域
   ======================================== */
.main-content {
    flex: 1;
    margin-left: 240px;
    padding: var(--spacing-xl);
    min-height: 100vh;
}

.page {
    display: none;
    animation: fadeIn 0.4s ease;
}

.page.active {
    display: block;
}

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

/* 页面头部 */
.page-header {
    margin-bottom: var(--spacing-xl);
}

.page-header h2 {
    font-size: 28px;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
    font-weight: 700;
}

.page-header p {
    color: var(--text-secondary);
    font-size: 16px;
}

/* ========================================
   首页欢迎区
   ======================================== */
.welcome-section {
    text-align: center;
    padding: var(--spacing-xl) 0;
    margin-bottom: var(--spacing-lg);
}

.welcome-section h1 {
    font-size: 32px;
    color: var(--text-primary);
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.welcome-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
}

/* ========================================
   卡片网格布局
   ======================================== */
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.card {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    transition: all var(--transition-normal);
    cursor: default;
}

.card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
}

.card-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
}

.badge {
    background: linear-gradient(135deg, var(--primary-light), var(--primary-color));
    color: white;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
}

.date-today {
    color: var(--text-muted);
    font-size: 14px;
}

.view-all {
    color: var(--primary-color);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: color var(--transition-fast);
}

.view-all:hover {
    color: var(--primary-dark);
}

.status {
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
}

.status.good {
    background: rgba(129, 199, 132, 0.2);
    color: #4CAF50;
}

.status.warning {
    background: rgba(255, 183, 77, 0.2);
    color: #F57C00;
}

.status.bad {
    background: rgba(229, 115, 115, 0.2);
    color: #E53935;
}

/* ========================================
   AI预览卡片
   ======================================== */
.ai-preview-card {
    cursor: pointer;
}

.ai-preview-container {
    text-align: center;
}

.mini-avatar {
    width: 120px;
    height: 120px;
    margin: 0 auto var(--spacing-md);
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, #BBDEFB, #90CAF9);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 60px;
    animation: gentle-bounce 2s ease-in-out infinite;
}

@keyframes gentle-bounce {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

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

/* ========================================
   进度卡片
   ======================================== */
.progress-content {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.progress-ring-container {
    position: relative;
    width: 120px;
    height: 120px;
    flex-shrink: 0;
}

.progress-ring {
    width: 100%;
    height: 100%;
    transform: rotate(-90deg);
}

.progress-bar {
    transition: stroke-dashoffset 0.6s ease;
}

.progress-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
}

.progress-stats {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    flex: 1;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 22px;
    font-weight: 700;
    color: var(--primary-color);
}

.stat-label {
    font-size: 13px;
    color: var(--text-muted);
}

/* ========================================
   课程迷你卡片
   ======================================== */
.recent-courses {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.course-mini {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-sm);
    border-radius: var(--radius-md);
    transition: background var(--transition-fast);
}

.course-mini:hover {
    background: var(--bg-tertiary);
}

.course-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
}

.course-icon.math { background: var(--accent-blue-light, #E3F2FD); }
.course-icon.english { background: var(--accent-green-light, #E8F5E9); }
.course-icon.code { background: var(--accent-purple-light, #F3E5F5); }

.course-info {
    flex: 1;
}

.course-info h4 {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 4px;
    color: var(--text-primary);
}

.course-progress-mini {
    height: 6px;
    background: var(--border-color);
    border-radius: 3px;
    overflow: hidden;
    display: inline-block;
    width: 100px;
    vertical-align: middle;
    margin-right: 8px;
}

.course-progress-mini .bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--primary-light));
    border-radius: 3px;
    transition: width var(--transition-normal);
}

.progress-percent {
    font-size: 12px;
    color: var(--primary-color);
    font-weight: 600;
}

/* ========================================
   应用使用概览
   ======================================== */
.apps-usage-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.usage-item {
    display: grid;
    grid-template-columns: 100px 1fr 80px;
    align-items: center;
    gap: var(--spacing-md);
}

.app-name {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
}

.usage-bar {
    height: 8px;
    background: var(--border-color);
    border-radius: 4px;
    overflow: hidden;
}

.usage-bar .fill {
    height: 100%;
    border-radius: 4px;
    transition: width var(--transition-slow);
}

.fill.study { background: var(--success); }
.fill.social { background: var(--warning); }
.fill.other { background: var(--secondary-color); }

.usage-time {
    font-size: 13px;
    color: var(--text-muted);
    text-align: right;
}

/* ========================================
   每日激励卡片
   ======================================== */
.motivation-card {
    background: linear-gradient(135deg, #E3F2FD, #BBDEFB);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg) var(--spacing-xl);
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    animation: fadeInUp 0.6s ease;
    border: 1px solid rgba(91, 155, 213, 0.2);
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.motivation-icon {
    font-size: 48px;
    animation: pulse-gentle 2s ease-in-out infinite;
}

@keyframes pulse-gentle {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

.motivation-text {
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-primary);
    font-weight: 500;
    font-style: italic;
}

/* ========================================
   按钮样式
   ======================================== */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    font-family: inherit;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    box-shadow: 0 4px 12px rgba(91, 155, 213, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(91, 155, 213, 0.4);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--border-color);
}

.btn-fun {
    background: linear-gradient(135deg, var(--accent-purple), #A080D0);
    color: white;
    box-shadow: 0 4px 12px rgba(184, 160, 216, 0.3);
}
.btn-fun:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(184, 160, 216, 0.4);
}

.btn-success {
    background: linear-gradient(135deg, var(--accent-green), #6BBF8E);
    color: white;
    box-shadow: 0 4px 12px rgba(149, 213, 178, 0.3);
}
.btn-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(149, 213, 178, 0.4);
}

/* ========================================
   浮动AI助手
   ======================================== */
.floating-ai-btn {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 60px;
    height: 60px;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    transition: all var(--transition-normal);
}

.floating-ai-btn:hover {
    transform: scale(1.1);
    box-shadow: var(--shadow-hover);
}

.floating-ai-btn .ai-face {
    font-size: 28px;
    animation: wave 1s ease-in-out infinite;
}

/* SVG形象容器（聊天框用） */
.ai-face-container {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    overflow: hidden;
    background: linear-gradient(135deg, #FFF8F0, #FFEDE5);
}

.ai-face-container svg {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

@keyframes wave {
    0%, 100% { transform: rotate(0deg); }
    25% { transform: rotate(15deg); }
    75% { transform: rotate(-15deg); }
}

.ai-pulse {
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: var(--radius-full);
    background: var(--primary-color);
    opacity: 0;
    animation: ripple 2s ease-out infinite;
}

@keyframes ripple {
    0% {
        transform: scale(1);
        opacity: 0.4;
    }
    100% {
        transform: scale(1.8);
        opacity: 0;
    }
}

/* AI对话弹窗 */
.ai-chat-popup {
    position: fixed;
    bottom: 100px;
    right: 30px;
    width: 380px;
    max-height: 520px;
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    z-index: 1001;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    animation: slideUp 0.3s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.ai-chat-popup.hidden {
    display: none;
}

.chat-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) var(--spacing-lg);
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
}

.chat-header h4 {
    font-size: 16px;
    font-weight: 600;
}

.close-chat {
    background: none;
    border: none;
    color: white;
    font-size: 28px;
    cursor: pointer;
    line-height: 1;
    opacity: 0.8;
    transition: opacity var(--transition-fast);
}

.close-chat:hover {
    opacity: 1;
}

.chat-messages {
    flex: 1;
    padding: var(--spacing-lg);
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    min-height: 300px;
}

.message {
    display: flex;
    gap: var(--spacing-sm);
    animation: messageIn 0.3s ease;
}

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

.msg-avatar {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, #FFF8F0, #FFEDE5);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    flex-shrink: 0;
    overflow: hidden;
}

/* SVG形象在消息中的显示 */
.msg-avatar svg {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

/* 聊天窗口头部头像 */
.chat-avatar-small {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, #FFF8F0, #FFEDE5);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    flex-shrink: 0;
    overflow: hidden;
}

.chat-avatar-small svg {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.msg-content {
    background: var(--bg-tertiary);
    padding: var(--spacing-md);
    border-radius: var(--radius-lg);
    border-top-left-radius: var(--radius-sm);
    max-width: 280px;
}

.user-message .msg-content {
    background: linear-gradient(135deg, var(--primary-light), var(--primary-color));
    color: white;
    border-radius: var(--radius-lg);
    border-top-right-radius: var(--radius-sm);
}

.msg-content p {
    font-size: 14px;
    line-height: 1.5;
}

.chat-input-area {
    display: flex;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    border-top: 1px solid var(--border-color);
}

.chat-input-area input {
    flex: 1;
    padding: 10px 16px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    font-family: inherit;
    font-size: 14px;
    outline: none;
    transition: border-color var(--transition-fast);
}

.chat-input-area input:focus {
    border-color: var(--primary-color);
}

.send-btn {
    padding: 10px 20px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    border: none;
    border-radius: var(--radius-xl);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.send-btn:hover {
    transform: scale(1.05);
}

/* ========================================
   响应式设计
   ======================================== */
@media (max-width: 1024px) {
    .sidebar {
        width: 200px;
    }

    .main-content {
        margin-left: 200px;
    }

    .dashboard-grid {
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    }
}

@media (max-width: 768px) {
    .sidebar {
        width: 60px;
        padding: var(--spacing-md) 0;
    }

    .logo-text,
    .nav-item span:not(.nav-icon),
    .user-info span {
        display: none;
    }

    .nav-item {
        justify-content: center;
        padding: var(--spacing-md);
    }

    .main-content {
        margin-left: 60px;
        padding: var(--spacing-md);
    }

    .welcome-section h1 {
        font-size: 24px;
    }

    .dashboard-grid {
        grid-template-columns: 1fr;
    }

    .progress-content {
        flex-direction: column;
        text-align: center;
    }

    .ai-chat-popup {
        width: calc(100vw - 80px);
        right: 20px;
        bottom: 90px;
    }
}

/* ========================================
   工具类
   ======================================== */
.hidden {
    display: none !important;
}

.text-center {
    text-align: center;
}

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

.text-success {
    color: var(--success);
}

.text-warning {
    color: var(--warning);
}

.positive {
    color: var(--success);
}

.negative {
    color: var(--error);
}