/* =====================================================================
   南大图谱 · 校园美食地图 — 南大紫色主题风格
   主色: #4B0082 (Indigo / 南大紫) 辅色: #7B2D8E
   ===================================================================== */

/* ========== CSS 变量 ========== */
:root {
    --njupurple: #4B0082;
    --njupurple-dark: #310059;
    --njupurple-light: #7B2D8E;
    --njupurple-bg: #F5F0FF;
    --njupurple-glow: rgba(75, 0, 130, 0.15);
    --side-width: 220px;
    --msg-width: 280px;
    --topbar-height: 56px;
    --gray-50: #fafafa;
    --gray-100: #f5f3f7;
    --gray-200: #e8e5ed;
    --gray-300: #d1cbd8;
    --gray-600: #6b6572;
    --gray-800: #2d2636;
    --card-shadow: 0 4px 20px rgba(75, 0, 130, 0.08);
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ========== 全局重置 ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
    width: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', Roboto, sans-serif;
    background: var(--njupurple-bg);
    color: var(--gray-800);
    min-height: 100vh;
    overflow-x: hidden;
}

/* =====================================================================
   三栏布局
   ===================================================================== */
.app-layout {
    display: flex;
    min-height: 100vh;
    width: 100%;
}

/* ========== 左侧栏 ========== */
.sidebar {
    width: var(--side-width);
    min-width: var(--side-width);
    background: linear-gradient(180deg, var(--njupurple-dark) 0%, var(--njupurple) 40%, var(--njupurple-light) 100%);
    color: white;
    display: flex;
    flex-direction: column;
    position: sticky;
    top: 0;
    height: 100vh;
    z-index: 200;
    box-shadow: 4px 0 24px rgba(75, 0, 130, 0.2);
    overflow-y: auto;
}

.sidebar-header {
    padding: 1.2rem 1.2rem 0.8rem;
    border-bottom: 1px solid rgba(255,255,255,0.12);
}

.site-logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-img {
    width: 36px;
    height: 36px;
    border-radius: 8px;
}

.logo-text {
    font-size: 1.3rem;
    font-weight: 700;
    letter-spacing: 1px;
    background: linear-gradient(135deg, #fff, #e0c8ff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.sidebar-nav {
    flex: 1;
    padding: 0.8rem 0.6rem;
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 0.7rem 1rem;
    color: rgba(255,255,255,0.7);
    text-decoration: none;
    border-radius: 10px;
    font-size: 0.95rem;
    font-weight: 500;
    transition: var(--transition);
}

.nav-item i {
    width: 20px;
    text-align: center;
    font-size: 1.1rem;
}

.nav-item:hover {
    background: rgba(255,255,255,0.12);
    color: white;
}

.nav-item.active {
    background: rgba(255,255,255,0.18);
    color: white;
    box-shadow: inset 3px 0 0 #ffb347;
}

.sidebar-footer {
    padding: 1rem;
    border-top: 1px solid rgba(255,255,255,0.1);
}

.sidebar-version {
    font-size: 0.75rem;
    opacity: 0.4;
    text-align: center;
}

/* ========== 主内容区 ========== */
.main-content {
    flex: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    background: var(--njupurple-bg);
}

/* ========== 顶栏 ========== */
.top-bar {
    height: var(--topbar-height);
    border-bottom: 1px solid var(--gray-200);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 1.5rem;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(12px);
    background: rgba(255,255,255,0.85);
}

.top-bar-left {
    display: flex;
    align-items: center;
    gap: 12px;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.2rem;
    color: var(--njupurple);
    cursor: pointer;
    padding: 4px;
}

.page-title {
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--njupurple-dark);
}

/* 未登录时顶栏标题 */
body:not(.logged-in) .top-bar .page-title {
    color: var(--njupurple);
}

.top-bar-right {
    display: flex;
    align-items: center;
    gap: 12px;
}

/* 圆形登录按钮 */
.login-round-btn {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--njupurple), var(--njupurple-light));
    color: white;
    border: none;
    font-size: 0.85rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 4px 12px rgba(75, 0, 130, 0.3);
    letter-spacing: 1px;
}

.login-round-btn:hover {
    transform: scale(1.06);
    box-shadow: 0 6px 20px rgba(75, 0, 130, 0.4);
}

.topbar-user {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--njupurple-bg);
    padding: 0.3rem 0.3rem 0.3rem 1rem;
    border-radius: 40px;
    border: 1px solid var(--gray-200);
}

.topbar-username {
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--njupurple);
}

.logout-btn {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    border: none;
    background: transparent;
    color: var(--gray-600);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.logout-btn:hover {
    background: #fee2e2;
    color: #dc2626;
}

/* ========== 内容区域 ========== */
.content-area {
    flex: 1;
    padding: 1.5rem;
    overflow-y: auto;
}

.page {
    display: none;
    animation: fadeSlideUp 0.3s ease;
}

.page.active-page {
    display: block;
}

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

/* ========== 未登录主页 — 简介区 ========== */
.hero-wrapper {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: calc(100vh - var(--topbar-height) - 80px);
    padding: 2rem 0;
}

.hero-content {
    text-align: center;
    max-width: 900px;
    width: 100%;
    padding: 0 1rem;
}

.hero-badge {
    display: inline-block;
    background: rgba(75, 0, 130, 0.08);
    color: var(--njupurple);
    padding: 0.4rem 1.4rem;
    border-radius: 40px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    border: 1px solid rgba(75, 0, 130, 0.12);
    letter-spacing: 0.5px;
}

.hero-title {
    font-size: 3.6rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--njupurple-dark), var(--njupurple-light), #9b59b6);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    margin-bottom: 0.8rem;
    line-height: 1.2;
    letter-spacing: -0.5px;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--gray-600);
    max-width: 550px;
    margin: 0 auto 2rem;
    line-height: 1.7;
}

.hero-actions {
    margin-bottom: 3rem;
}

.hero-btn {
    background: linear-gradient(135deg, var(--njupurple), var(--njupurple-light));
    color: white;
    border: none;
    padding: 0.9rem 2.5rem;
    border-radius: 60px;
    font-size: 1.1rem;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 6px 24px rgba(75, 0, 130, 0.3);
}

.hero-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 32px rgba(75, 0, 130, 0.4);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-top: 1rem;
}

.feature-card {
    background: white;
    border-radius: 20px;
    padding: 1.8rem 1.5rem;
    border: 1px solid var(--gray-200);
    transition: var(--transition);
    box-shadow: var(--card-shadow);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(75, 0, 130, 0.12);
    border-color: var(--njupurple-light);
}

.feature-card i {
    font-size: 2.2rem;
    color: var(--njupurple);
    margin-bottom: 0.8rem;
}

.feature-card h3 {
    font-size: 1.1rem;
    margin-bottom: 0.4rem;
    color: var(--njupurple-dark);
}

.feature-card p {
    font-size: 0.9rem;
    color: var(--gray-600);
}

/* ========== 页面通用 ========== */
.page-header-flex {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.page-header-flex h2 {
    font-size: 1.3rem;
    color: var(--njupurple-dark);
}

.page-placeholder {
    text-align: center;
    padding: 5rem 2rem;
    color: var(--gray-600);
}

.page-placeholder h2 {
    margin: 1rem 0 0.5rem;
    color: var(--njupurple);
}

/* ========== 餐厅卡片 ========== */
.resto-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 1rem;
}

.resto-card {
    background: white;
    border-radius: 20px;
    overflow: hidden;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--card-shadow);
    border: 1px solid var(--gray-200);
}

.resto-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(75, 0, 130, 0.15);
    border-color: var(--njupurple-light);
}

.resto-img {
    height: 160px;
    background-size: cover;
    background-position: center;
    background-color: var(--gray-200);
}

.resto-info {
    padding: 1rem 1.1rem;
}

.resto-name {
    font-weight: 700;
    font-size: 1.15rem;
    margin-bottom: 0.2rem;
    color: var(--gray-800);
}

/* ========== 地图 ========== */
#mapContainer {
    width: 100%;
    height: 520px;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--card-shadow);
    margin: 1rem 0;
    background: var(--gray-200);
    border: 1px solid var(--gray-200);
}

/* ========== AI 聊天 ========== */
.ai-hint {
    color: var(--gray-600);
    margin-bottom: 0.8rem;
    font-size: 0.9rem;
}

.chat-area {
    background: white;
    border-radius: 20px;
    padding: 1.2rem;
    height: 420px;
    overflow-y: auto;
    border: 1px solid var(--gray-200);
    box-shadow: var(--card-shadow);
}

.chat-message {
    margin: 0.7rem 0;
    padding: 0.7rem 1rem;
    border-radius: 18px;
    max-width: 85%;
    word-wrap: break-word;
    line-height: 1.5;
}

.chat-user {
    background: var(--njupurple-bg);
    margin-left: auto;
    text-align: right;
    border-bottom-right-radius: 4px;
    color: var(--njupurple-dark);
}

.chat-bot {
    background: #f8f5ff;
    border-bottom-left-radius: 4px;
    border: 1px solid rgba(75, 0, 130, 0.06);
}

.chat-input-area {
    display: flex;
    gap: 0.8rem;
    margin-top: 1rem;
}

.chat-input-area input {
    flex: 1;
    padding: 0.8rem 1.2rem;
    border-radius: 60px;
    border: 1px solid var(--gray-300);
    background: white;
    font-size: 0.95rem;
    transition: 0.2s;
}

.chat-input-area input:focus {
    outline: none;
    border-color: var(--njupurple);
    box-shadow: 0 0 0 3px rgba(75, 0, 130, 0.12);
}

/* ========== 右侧消息栏 ========== */
.message-panel {
    width: var(--msg-width);
    min-width: var(--msg-width);
    background: white;
    border-left: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    height: 100vh;
    position: sticky;
    top: 0;
}

.message-panel-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 1rem 1.2rem;
    font-weight: 700;
    font-size: 1rem;
    color: var(--njupurple-dark);
    border-bottom: 1px solid var(--gray-200);
}

.message-panel-body {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
}

.message-empty {
    text-align: center;
    padding: 3rem 0;
    color: var(--gray-300);
}

.message-empty i {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.message-empty p {
    font-size: 0.9rem;
}

.message-item {
    display: flex;
    gap: 10px;
    padding: 0.8rem;
    border-radius: 12px;
    transition: var(--transition);
    cursor: pointer;
}

.message-item:hover {
    background: var(--njupurple-bg);
}

.message-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--njupurple-light);
    margin-top: 6px;
    flex-shrink: 0;
}

.message-content {
    flex: 1;
    min-width: 0;
}

.message-title {
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--gray-800);
}

.message-time {
    font-size: 0.75rem;
    color: var(--gray-600);
    margin-top: 2px;
}

/* ========== 底栏 ========== */
.site-footer {
    border-top: 1px solid var(--gray-200);
    background: white;
    padding: 1rem 1.5rem;
    margin-top: auto;
}

.footer-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.8rem;
    max-width: 1200px;
    margin: 0 auto;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.footer-logo {
    font-weight: 700;
    color: var(--njupurple);
    font-size: 1rem;
}

.footer-desc {
    font-size: 0.8rem;
    color: var(--gray-600);
}

.footer-copyright {
    font-size: 0.8rem;
    color: var(--gray-600);
    text-align: right;
}

/* ========== 模态框 ========== */
.modal {
    display: none;
    position: fixed;
    top:0; left:0;
    width:100%; height:100%;
    background: rgba(49, 0, 89, 0.5);
    backdrop-filter: blur(12px);
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal-card {
    background: white;
    border-radius: 28px;
    width: 90%;
    max-width: 460px;
    padding: 2rem 1.8rem;
    box-shadow: 0 25px 50px rgba(75, 0, 130, 0.2);
    position: relative;
    animation: modalPop 0.25s ease;
}

@keyframes modalPop {
    from { opacity: 0; transform: scale(0.95) translateY(8px); }
    to   { opacity: 1; transform: scale(1) translateY(0); }
}

.modal-close-btn {
    position: absolute;
    top: 12px;
    right: 12px;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    border: none;
    background: var(--gray-100);
    color: var(--gray-600);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-close-btn:hover {
    background: var(--njupurple-bg);
    color: var(--njupurple);
}
.modal-card h2 {
    margin-bottom: 1.2rem;
    color: var(--njupurple-dark);
    font-size: 1.4rem;
}

.modal-card input, .modal-card textarea {
    width: 100%;
    margin-bottom: 0.9rem;
    padding: 0.8rem 1rem;
    border-radius: 16px;
    border: 1px solid var(--gray-300);
    background: var(--gray-50);
    transition: 0.2s;
    font-size: 0.95rem;
}

.modal-card input:focus {
    border-color: var(--njupurple);
    outline: none;
    box-shadow: 0 0 0 3px rgba(75, 0, 130, 0.1);
    background: white;
}

.modal-actions {
    display: flex;
    gap: 0.8rem;
    margin: 1rem 0;
}

.switch-mode {
    text-align: center;
    margin-top: 0.8rem;
    font-size: 0.9rem;
    color: var(--gray-600);
}

.switch-mode a {
    color: var(--njupurple-light);
    cursor: pointer;
    font-weight: 600;
    text-decoration: none;
}

.switch-mode a:hover {
    text-decoration: underline;
}

.flex-between {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.close-btn {
    background: var(--gray-100);
    border: none;
    font-size: 1.1rem;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    cursor: pointer;
    transition: 0.2s;
}

.close-btn:hover {
    background: var(--njupurple-bg);
    color: var(--njupurple);
}

/* ========== 按钮 ========== */
.primary-btn, .secondary-btn, .small-btn {
    border: none;
    padding: 0.65rem 1.5rem;
    border-radius: 60px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.primary-btn {
    background: linear-gradient(135deg, var(--njupurple), var(--njupurple-light));
    color: white;
    box-shadow: 0 4px 12px rgba(75, 0, 130, 0.2);
}

.primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(75, 0, 130, 0.3);
}

.secondary-btn {
    background: var(--gray-100);
    color: var(--njupurple-dark);
    border: 1px solid var(--gray-200);
}

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

.small-btn {
    background: var(--gray-100);
    color: var(--gray-800);
    padding: 0.25rem 1rem;
    font-size: 0.8rem;
    border: 1px solid var(--gray-200);
}

.small-btn:hover {
    background: var(--njupurple-bg);
    color: var(--njupurple);
}

/* ========== 个人中心 ========== */
.profile-card {
    background: white;
    border-radius: 20px;
    padding: 1.5rem;
    box-shadow: var(--card-shadow);
    margin-top: 1rem;
    border: 1px solid var(--gray-200);
}

.profile-card hr {
    margin: 1.5rem 0;
    border: none;
    height: 1px;
    background: var(--gray-200);
}

.profile-card h3 {
    margin: 1rem 0 0.5rem;
    color: var(--njupurple-dark);
}

/* ========== Toast 提示 ========== */
.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--njupurple-dark);
    backdrop-filter: blur(12px);
    color: white;
    padding: 10px 24px;
    border-radius: 60px;
    z-index: 2000;
    font-size: 0.9rem;
    font-weight: 500;
    letter-spacing: 0.3px;
    pointer-events: none;
    box-shadow: 0 6px 24px rgba(75, 0, 130, 0.3);
}

/* =====================================================================
   响应式 — 小屏幕
   ===================================================================== */
@media (max-width: 1100px) {
    .message-panel {
        display: none;
    }
}

@media (max-width: 768px) {
    .sidebar {
        position: fixed;
        left: -280px;
        transition: left 0.3s ease;
        z-index: 300;
        box-shadow: 4px 0 30px rgba(0,0,0,0.3);
    }

    .sidebar.open {
        left: 0;
    }

    .menu-toggle {
        display: block;
    }

    .sidebar-overlay {
        display: none;
        position: fixed;
        top: 0; left: 0; right: 0; bottom: 0;
        background: rgba(0,0,0,0.4);
        z-index: 299;
    }

    .sidebar-overlay.show {
        display: block;
    }

    .content-area {
        padding: 1rem;
    }

    .hero-title {
        font-size: 2.2rem;
    }

    .footer-inner {
        flex-direction: column;
        text-align: center;
    }

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

/* ========== 快捷提问按钮 ========== */
.quick-questions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
    margin: 0.8rem 0;
}

.quick-q-btn {
    background: white;
    border: 1px solid var(--gray-200);
    padding: 0.5rem 1.2rem;
    border-radius: 60px;
    font-size: 0.85rem;
    color: var(--njupurple);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
    white-space: nowrap;
    box-shadow: var(--card-shadow);
}

.quick-q-btn:hover {
    background: var(--njupurple-bg);
    border-color: var(--njupurple-light);
    transform: translateY(-1px);
}
.code-row {
    display: flex;
    gap: 8px;
    align-items: center;
}

.code-row input {
    flex: 1;
    min-width: 0;
}

.code-row button {
    white-space: nowrap;
}