/**
 * Chat Welcome Screen Styles
 * 聊天歡迎畫面樣式 - 極簡版
 *
 * 設計理念：像 Google 首頁一樣簡潔
 * 響應式：支援桌面（>768px）、平板（481-768px）、手機（≤480px）
 *
 * Design Token Migration: 2026-02-16
 * 所有硬編碼色碼已遷移至 brand-system.css 定義的 Design Token
 * 舊 :root 區塊的 --brand-* / --bg-* / --text-* 變數已由 brand-system.css 統一管理
 */

/* ========== 容器 ========== */
.chat-welcome-container {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    padding: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    /* 移除 min-height，讓內容自適應 */
}

/* 當容器在 welcome-screen 內時的特殊樣式 */
.welcome-screen .chat-welcome-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
}

/* ========== 第一層：歡迎標題 ========== */
.welcome-header {
    width: 100%;
    text-align: center;
    margin-bottom: 48px;
    opacity: 0;  /* 初始隱藏，等待動畫 */
}

.welcome-title {
    color: var(--color-text-primary);
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 12px;
    line-height: 1.3;
    letter-spacing: -0.02em;
}

.welcome-subtitle {
    color: var(--color-text-tertiary);
    font-size: 16px;
    line-height: 1.6;
    font-weight: 400;
}

/* ========== 第二層：AI 能力展示 ========== */
.ai-capabilities {
    width: 100%;
    margin-bottom: 40px;
}

.ai-capabilities-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
}

.ai-capability-card {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border-strong);
    border-radius: var(--border-radius-lg, 16px);
    padding: 20px 16px;
    text-align: center;
    transition: all 0.2s ease;
    cursor: default;
    opacity: 0;  /* 初始隱藏，等待動畫 */
    box-shadow: var(--shadow-xs);
}

.ai-capability-card[data-capability="smart-filter"] {
    cursor: pointer;
}

.ai-capability-card:hover {
    background: var(--color-bg-hover);
    border-color: var(--color-border-strong);
}

.capability-icon {
    font-size: 40px;
    margin-bottom: 12px;
}

.capability-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: 8px;
}

.capability-desc {
    font-size: 13px;
    color: var(--color-text-secondary);
    line-height: 1.5;
}

/* ========== 第三層：智能推薦 ========== */
.recommendations {
    width: 100%;
    margin-bottom: 32px;
}

.recommendations-header {
    margin-bottom: 16px;
}

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

.recommendations-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.recommendation-card {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border-strong);
    border-radius: 14px;
    padding: 16px 20px;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    align-items: center;
    gap: 12px;
    opacity: 0;  /* 初始隱藏，等待動畫 */
    box-shadow: var(--shadow-xs);
}

.recommendation-card:hover {
    background: var(--color-bg-elevated);
    border-color: var(--color-accent);
    box-shadow: 0 4px 14px var(--color-accent-subtle);
    transform: translateY(-2px);
}

.recommendation-card:active {
    transform: translateY(0);
    box-shadow: var(--shadow-xs);
}

.card-icon {
    font-size: 24px;
    flex-shrink: 0;
}

.card-text {
    flex: 1;
    font-size: 15px;
    color: var(--color-text-primary);
    font-weight: 600;
}

.card-tag {
    font-size: 11px;
    color: var(--color-text-tertiary);
    background: rgba(0, 0, 0, 0.05);
    padding: 4px 12px;
    border-radius: 12px;
    flex-shrink: 0;
    font-weight: 500;
}

/* ========== 第四層：輸入提示 ========== */
.input-hint {
    width: 100%;
    text-align: center;
    color: var(--color-text-tertiary);
    font-size: 14px;
    position: relative;
    padding-bottom: 16px;
    opacity: 0.6;  /* 初始略暗，等待脈動動畫 */
}

.input-hint::after {
    display: none;
}

/* ========== 跳過動畫按鈕 ========== */
.skip-animation-btn {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border-strong);
    color: var(--color-text-secondary);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s ease;
    z-index: 1000;
}

.skip-animation-btn:hover {
    background: var(--color-bg-hover);
    border-color: var(--color-border-strong);
    color: var(--color-text-primary);
}

/* ========== 動畫關鍵幀定義 ========== */

/* 淡入向上動畫（標題使用） */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 浮入縮放動畫（AI 能力卡片使用） */
@keyframes floatIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* 向上浮現動畫（推薦卡片使用） */
@keyframes floatInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 脈動動畫（輸入提示使用） */
@keyframes pulse {
    0%, 100% {
        opacity: 0.5;
    }
    50% {
        opacity: 0.8;
    }
}

/* ========== 動畫速度類別 ========== */

/* 首次訪問：慢速動畫 */
.animation-first .welcome-header {
    animation: fadeInUp 800ms ease-out forwards;
}

.animation-first .ai-capability-card {
    animation: floatIn 600ms ease-out forwards;
}

.animation-first .recommendation-card {
    animation: floatInUp 500ms ease-out forwards;
}

.animation-first .input-hint {
    animation: pulse 2s ease-in-out infinite;
}

/* 標準訪問：中速動畫 */
.animation-normal .welcome-header {
    animation: fadeInUp 400ms ease-out forwards;
}

.animation-normal .ai-capability-card {
    animation: floatIn 400ms ease-out forwards;
}

.animation-normal .recommendation-card {
    animation: floatInUp 400ms ease-out forwards;
}

.animation-normal .input-hint {
    animation: pulse 2s ease-in-out infinite;
}

/* 多次訪問：快速動畫 */
.animation-fast .welcome-header {
    animation: fadeInUp 200ms ease-out forwards;
}

.animation-fast .ai-capability-card {
    animation: floatIn 200ms ease-out forwards;
}

.animation-fast .recommendation-card {
    animation: floatInUp 200ms ease-out forwards;
}

.animation-fast .input-hint {
    animation: pulse 2s ease-in-out infinite;
}

/* ========== 通用動畫工具類別 ========== */

/* 隱藏元素（用於動畫前） */
[data-animate] {
    opacity: 0;
}

/* 跳過動畫後的最終狀態 */
[data-animate-skip] {
    animation: none !important;
    opacity: 1 !important;
    transform: none !important;
}

/* ========== 列印樣式 ========== */
@media print {
    .skip-animation-btn {
        display: none;
    }

    .chat-welcome-container {
        padding: 0;
    }

    .ai-capability-card,
    .recommendation-card {
        break-inside: avoid;
    }
}

/* ========== AI Chat 介面整合樣式 ========== */

/* 歡迎畫面包裝器 */
.chat-welcome-wrapper {
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 500px;
    padding: 40px 20px;
}

/* 在 AI Chat 介面中的特殊樣式 */
.ai-chat-app .chat-welcome-container {
    background: transparent;
}

/* 調整歡迎標題在 AI Chat 中的樣式 */
.ai-chat-app .welcome-title {
    font-size: 26px;
}

/* 調整 AI 能力卡片的網格 */
.ai-chat-app .ai-capabilities-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
}

.ai-chat-app .ai-capability-card {
    padding: 16px 14px;
}

.ai-chat-app .capability-icon {
    font-size: 32px;
    margin-bottom: 10px;
}

.ai-chat-app .capability-title {
    font-size: 14px;
}

.ai-chat-app .capability-desc {
    font-size: 12px;
}

/* 推薦卡片在 AI Chat 中的調整 */
.ai-chat-app .recommendation-card {
    padding: 14px 18px;
}

.ai-chat-app .card-text {
    font-size: 14px;
}

/* 輸入提示在 AI Chat 中的調整 */
.ai-chat-app .input-hint {
    font-size: 13px;
    padding-bottom: 12px;
}

/* ========== 極簡版歡迎畫面樣式 ========== */

/* 極簡主容器 - 垂直置中 */
.chat-welcome-minimalist {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    max-width: 680px;
    margin: 0 auto;
    padding: 80px 20px;
    min-height: 300px;
    animation: simpleFadeIn 0.5s ease-out;
}

/* 極簡標題 */
.welcome-title-minimalist {
    font-size: 26px;
    font-weight: 700;
    color: var(--color-text-primary);
    text-align: center;
    margin-bottom: 40px;
    line-height: 1.4;
    letter-spacing: -0.02em;
}

/* 搜尋框（含真實輸入框 - Claude.ai 風格） */
.welcome-search-box {
    display: flex;
    align-items: center;
    width: 100%;
    max-width: 600px;
    padding: 12px 16px;
    background: var(--color-bg-elevated);
    border: 1.5px solid var(--color-border-strong);
    border-radius: 28px;
    transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: var(--shadow-sm);
}

.welcome-search-box:hover {
    border-color: var(--color-border-strong);
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

.welcome-search-box:focus-within {
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px var(--color-accent-subtle), var(--shadow-md);
    transform: translateY(-1px);
}

.search-icon {
    font-size: 18px;
    margin-right: 12px;
    color: var(--color-text-tertiary);
    flex-shrink: 0;
}

/* 真實輸入框 */
.welcome-input {
    flex: 1;
    border: none;
    outline: none;
    resize: none;
    font-size: 15px;
    line-height: 1.5;
    max-height: 120px;
    background: transparent;
    color: var(--color-text-primary);
    font-family: inherit;
}

.welcome-input::placeholder {
    color: var(--color-text-tertiary);
}

/* 發送按鈕 */
.welcome-send-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--color-accent);
    color: var(--color-text-on-accent);
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    margin-left: 12px;
    transition: all 0.2s ease;
}

.welcome-send-btn:hover {
    background: var(--color-accent-hover);
    transform: scale(1.08);
    box-shadow: var(--shadow-accent);
}

.welcome-send-btn:active {
    transform: scale(0.92);
    box-shadow: var(--shadow-accent);
}

.welcome-send-btn svg {
    width: 18px;
    height: 18px;
}

/* 隱藏 placeholder span（保留相容性） */
.search-placeholder {
    display: none;
}

/* 情境標籤容器 */
.welcome-scenarios {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-top: 24px;
    flex-wrap: wrap;
}

/* 情境標籤間隔點 */
.scenario-separator {
    color: var(--color-text-tertiary);
    opacity: 0.5;
    font-size: 12px;
    user-select: none;
}

/* 可點擊情境標籤 */
.welcome-scenario-tag {
    display: inline-flex;
    align-items: center;
    padding: 8px 16px;
    font-size: 14px;
    color: var(--color-text-secondary);
    background: transparent;
    border: none;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.2s ease;
    min-height: 36px;
    font-weight: 500;
}

.welcome-scenario-tag:hover {
    color: var(--color-text-primary);
    background: rgba(0, 0, 0, 0.04);
}

.welcome-scenario-tag:active {
    transform: scale(0.96);
}

/* ========== 極簡提示 chips ========== */
.welcome-hint-chips {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    margin-top: 20px;
    flex-wrap: wrap;
}

.hint-chip {
    padding: 6px 14px;
    font-size: 13px;
    color: var(--color-text-secondary);
    background: transparent;
    border: 1px solid var(--color-border-strong);
    border-radius: 18px;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    white-space: nowrap;
    font-weight: 500;
}

.hint-chip:hover {
    color: var(--color-accent);
    border-color: var(--color-accent);
    background: var(--color-accent-muted);
    transform: translateY(-1px);
    box-shadow: 0 2px 8px var(--color-accent-subtle);
}

.hint-chip:active {
    transform: scale(0.95) translateY(0);
    box-shadow: none;
}

.hint-separator {
    color: var(--color-text-tertiary);
    opacity: 0.4;
    font-size: 12px;
    user-select: none;
}

/* Dark theme */
[data-theme="dark"] .hint-chip {
    background: var(--color-bg-tertiary);
    border-color: var(--color-bg-elevated);
    color: var(--color-text-secondary);
}

[data-theme="dark"] .hint-chip:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
    background: var(--color-accent-muted);
}

[data-theme="dark"] .hint-separator {
    color: var(--color-text-secondary);
}

[data-theme="dark"] .card-tag {
    background: rgba(255, 255, 255, 0.08);
    color: var(--color-text-secondary);
}

[data-theme="dark"] .welcome-scenario-tag:hover {
    background: rgba(255, 255, 255, 0.06);
}

[data-theme="dark"] .ai-capability-card {
    background: var(--color-bg-secondary);
    border-color: var(--color-border-default);
}

[data-theme="dark"] .ai-capability-card:hover {
    background: var(--color-bg-tertiary);
}

[data-theme="dark"] .recommendation-card {
    background: var(--color-bg-secondary);
    border-color: var(--color-border-default);
}

[data-theme="dark"] .recommendation-card:hover {
    background: var(--color-bg-secondary);
    border-color: var(--color-accent);
}

[data-theme="dark"] .welcome-search-box {
    background: var(--color-bg-secondary);
    border-color: var(--color-border-default);
}

[data-theme="dark"] .skip-animation-btn {
    background: var(--color-bg-secondary);
    border-color: var(--color-border-default);
}

/* 簡單淡入動畫 */
@keyframes simpleFadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ========== 極簡版響應式設計 ========== */

/* 平板 (481-768px) */
@media (max-width: 768px) {
    .chat-welcome-minimalist {
        padding: 40px 16px;
    }

    .welcome-title-minimalist {
        font-size: 22px;
        margin-bottom: 28px;
    }

    .welcome-search-box {
        max-width: 100%;
        padding: 10px 14px;
    }

    .welcome-input {
        font-size: 14px;
    }

    .welcome-send-btn {
        width: 36px;
        height: 36px;
        margin-left: 10px;
    }

    .welcome-send-btn svg {
        width: 16px;
        height: 16px;
    }
}

/* 手機 (≤480px) */
@media (max-width: 480px) {
    .chat-welcome-minimalist {
        padding: 32px 12px;
        min-height: 250px;
    }

    .welcome-title-minimalist {
        font-size: 20px;
        margin-bottom: 24px;
    }

    .welcome-search-box {
        padding: 10px 12px;
        border-radius: 24px;
    }

    .search-icon {
        font-size: 16px;
        margin-right: 10px;
    }

    .welcome-input {
        font-size: 13px;
    }

    .welcome-send-btn {
        width: 34px;
        height: 34px;
        margin-left: 8px;
    }

    .welcome-send-btn svg {
        width: 14px;
        height: 14px;
    }

    .welcome-hint-chips {
        gap: 4px;
    }

    .hint-chip {
        padding: 4px 10px;
        font-size: 12px;
    }

    .hint-separator {
        display: none;
    }
}