/**
 * Language Switcher Component Styles
 *
 * 提供三種樣式：
 * - dropdown: 下拉選單
 * - buttons: 按鈕列表
 * - minimal: 極簡切換
 */

/* ===== 基礎變數 ===== */
.lang-switcher {
    --lang-primary: var(--primary-color, #FF6B35);
    --lang-primary-light: var(--primary-light, #FFF0EB);
    --lang-text: var(--text-color, #333);
    --lang-text-secondary: var(--text-secondary, #666);
    --lang-border: var(--border-color, #e0e0e0);
    --lang-bg: var(--bg-color, #fff);
    --lang-hover-bg: var(--hover-bg, #f5f5f5);
    --lang-shadow: var(--shadow-md);
    --lang-radius: var(--radius-lg);
    --lang-transition: var(--hover-transition);
}

/* ===== 大小變體 ===== */
.lang-switcher--small {
    --lang-font-size: 12px;
    --lang-padding: 4px 8px;
    --lang-flag-size: 14px;
    --lang-gap: 4px;
}

.lang-switcher--medium {
    --lang-font-size: 14px;
    --lang-padding: 8px 12px;
    --lang-flag-size: 18px;
    --lang-gap: 6px;
}

.lang-switcher--large {
    --lang-font-size: 16px;
    --lang-padding: 10px 16px;
    --lang-flag-size: 22px;
    --lang-gap: 8px;
}

/* ===== 下拉選單樣式 ===== */
.lang-dropdown {
    position: relative;
    display: inline-block;
}

.lang-dropdown__trigger {
    display: inline-flex;
    align-items: center;
    gap: var(--lang-gap);
    padding: var(--lang-padding);
    background: transparent;
    border: none;
    border-radius: var(--lang-radius);
    cursor: pointer;
    font-size: var(--lang-font-size);
    font-family: inherit;
    color: var(--lang-text);
    transition: var(--lang-transition);
    white-space: nowrap;
}

.lang-dropdown__trigger:hover {
    background: var(--lang-hover-bg);
}

.lang-dropdown__trigger:focus {
    outline: none;
    box-shadow: 0 0 0 2px var(--lang-primary-light);
}

.lang-flag {
    font-size: var(--lang-flag-size);
    line-height: 1;
}

.lang-name {
    font-weight: 500;
}

.lang-code {
    font-weight: 600;
    letter-spacing: 0.5px;
}

.lang-arrow {
    transition: transform var(--duration-normal) var(--ease-out);
    opacity: 0.6;
}

.lang-dropdown__trigger[aria-expanded="true"] .lang-arrow {
    transform: rotate(180deg);
}

/* 下拉選單 */
.lang-dropdown__menu {
    position: absolute;
    top: calc(100% + 4px);
    min-width: 160px;
    background: var(--lang-bg);
    border: 1px solid var(--lang-border);
    border-radius: var(--lang-radius);
    box-shadow: var(--lang-shadow);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: var(--lang-transition);
    list-style: none;
    margin: 0;
    padding: 4px;
    z-index: var(--z-dropdown);
}

.lang-dropdown__menu--open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.lang-menu--right {
    right: 0;
}

.lang-menu--left {
    left: 0;
}

.lang-dropdown__menu li {
    margin: 0;
    padding: 0;
}

.lang-option {
    display: flex;
    align-items: center;
    gap: var(--lang-gap);
    width: 100%;
    padding: 10px 12px;
    background: none;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: var(--lang-font-size);
    font-family: inherit;
    text-align: left;
    color: var(--lang-text);
    transition: background var(--duration-fast) var(--ease-out);
}

.lang-option:hover {
    background: var(--lang-hover-bg);
}

.lang-option:focus {
    outline: none;
    background: var(--lang-hover-bg);
}

.lang-option--active {
    background: transparent;
    color: var(--lang-primary);
    font-weight: 500;
}

.lang-option--active:hover {
    background: var(--lang-hover-bg);
}

.lang-check {
    margin-left: auto;
    color: var(--lang-primary);
    flex-shrink: 0;
}

/* ===== 按鈕樣式 ===== */
.lang-buttons {
    display: inline-flex;
    gap: 4px;
    padding: 2px;
    background: var(--lang-hover-bg);
    border-radius: var(--lang-radius);
}

.lang-btn {
    display: inline-flex;
    align-items: center;
    gap: var(--lang-gap);
    padding: var(--lang-padding);
    background: transparent;
    border: none;
    border-radius: calc(var(--lang-radius) - 2px);
    cursor: pointer;
    font-size: var(--lang-font-size);
    font-family: inherit;
    color: var(--lang-text-secondary);
    transition: var(--lang-transition);
    white-space: nowrap;
}

.lang-btn:hover {
    color: var(--lang-text);
    background: rgba(255, 255, 255, 0.5);
}

.lang-btn:focus {
    outline: none;
    box-shadow: 0 0 0 2px var(--lang-primary-light);
}

.lang-btn--active {
    background: var(--lang-bg);
    color: var(--lang-primary);
    box-shadow: var(--shadow-xs);
    font-weight: 500;
}

.lang-btn--active:hover {
    background: var(--lang-bg);
}

/* ===== 極簡樣式 ===== */
.lang-minimal {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 6px 10px;
    background: transparent;
    border: none;
    cursor: pointer;
    font-size: 13px;
    font-family: inherit;
    color: var(--lang-text-secondary);
    text-decoration: none;
    transition: color var(--duration-normal) var(--ease-out);
    border-radius: var(--radius-sm);
}

.lang-minimal:hover {
    color: var(--lang-primary);
    background: var(--lang-primary-light);
}

.lang-minimal:focus {
    outline: none;
    color: var(--lang-primary);
    box-shadow: 0 0 0 2px var(--lang-primary-light);
}

/* ===== 深色模式支援 ===== */
@media (prefers-color-scheme: dark) {
    .lang-switcher {
        --lang-text: #e0e0e0;
        --lang-text-secondary: #a0a0a0;
        --lang-border: #444;
        --lang-bg: #2a2a2a;
        --lang-hover-bg: #333;
        --lang-shadow: var(--shadow-md);
    }

    .lang-buttons {
        background: #333;
    }

    .lang-btn--active {
        background: #444;
        box-shadow: var(--shadow-xs);
    }
}

/* 如果有 data-theme 屬性 */
[data-theme="dark"] .lang-switcher {
    --lang-text: #e0e0e0;
    --lang-text-secondary: #a0a0a0;
    --lang-border: #444;
    --lang-bg: #2a2a2a;
    --lang-hover-bg: #333;
    --lang-shadow: var(--shadow-md);
}

/* ===== 響應式設計 ===== */
@media (max-width: 480px) {
    .lang-switcher--medium {
        --lang-font-size: 13px;
        --lang-padding: 6px 10px;
    }

    .lang-dropdown__menu {
        min-width: 140px;
    }

    .lang-option {
        padding: 8px 10px;
    }
}

/* ===== 動畫 ===== */
@keyframes lang-fade-in {
    from {
        opacity: 0;
        transform: translateY(-8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.lang-dropdown__menu--open {
    animation: lang-fade-in var(--duration-normal) var(--ease-out);
}

/* ===== Auth 頁面定位 ===== */
.auth-lang-switcher {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: var(--z-fixed);
}

.auth-lang-switcher .lang-minimal {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    padding: 8px 14px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    font-weight: 500;
}

.auth-lang-switcher .lang-minimal:hover {
    background: rgba(255, 255, 255, 1);
}

/* ===== Visitor 頁面定位 (樣式在 visitor-chat.css 中定義) ===== */

/* ===== Landing 頁面定位 ===== */
.landing-lang-switcher,
#landing-lang-switcher {
    display: flex;
    align-items: center;
    margin-right: 8px;
    position: relative;
    z-index: var(--z-fixed);
    /* 預留空間避免 JS 初始化時的 layout shift */
    min-width: 69px;
    min-height: 34px;
}

.landing-lang-switcher .lang-dropdown {
    position: relative;
    z-index: var(--z-fixed);
}

.landing-lang-switcher .lang-dropdown__trigger {
    background: rgba(255, 255, 255, 0.9);
    border: none;
    padding: 6px 10px;
    border-radius: var(--radius-md);
    font-size: 13px;
}

.landing-lang-switcher .lang-dropdown__trigger:hover {
    background: rgba(255, 255, 255, 1);
}

/* 導航列滾動後的樣式 */
.landing-nav.scrolled .landing-lang-switcher .lang-dropdown__trigger {
    background: var(--bg-primary);
    box-shadow: var(--shadow-xs);
}

/* 手機版語言切換器 */
.landing-mobile-lang-switcher {
    display: flex;
    justify-content: center;
    padding: 16px 24px;
    border-top: 1px solid rgba(0, 0, 0, 0.08);
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
    margin: 16px 0;
}

.landing-mobile-lang-switcher .lang-buttons {
    background: var(--neutral-100);
}

.landing-mobile-lang-switcher .lang-btn {
    padding: 10px 20px;
    font-size: 15px;
}

.landing-mobile-lang-switcher .lang-btn--active {
    background: var(--bg-primary);
    color: var(--lang-primary);
}

/* ===== SSR 版本語言切換器 (首頁專用) ===== */

/* SSR 桌面版語言切換連結 */
.ssr-lang-switcher {
    display: flex;
    align-items: center;
    margin-right: 8px;
}

.ssr-lang-switcher .lang-switch-link {
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.9);
    border: none;
    padding: 8px 12px;
    border-radius: var(--radius-lg);
    text-decoration: none;
    color: var(--text-primary, #333);
    font-size: var(--text-sm);
    transition: var(--hover-transition);
}

.ssr-lang-switcher .lang-switch-link:hover {
    background: rgba(255, 255, 255, 1);
    transform: var(--hover-lift);
    box-shadow: var(--shadow-sm);
}

.ssr-lang-switcher .lang-flag {
    font-size: var(--text-lg);
    line-height: 1;
}

/* 導航列滾動後的 SSR 樣式 */
.landing-nav.scrolled .ssr-lang-switcher .lang-switch-link {
    background: var(--bg-primary);
    box-shadow: var(--shadow-xs);
}

/* SSR 手機版語言切換按鈕 */
.landing-mobile-lang-switcher .mobile-lang-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 16px;
    border-radius: var(--radius-lg);
    text-decoration: none;
    color: var(--text-secondary, #666);
    background: transparent;
    font-size: var(--text-sm);
    font-weight: 500;
    transition: var(--hover-transition);
}

.landing-mobile-lang-switcher .mobile-lang-btn:hover {
    background: rgba(255, 107, 53, 0.05);
    color: var(--lang-primary, #FF6B35);
}

.landing-mobile-lang-switcher .mobile-lang-btn.active {
    background: var(--bg-primary);
    color: var(--lang-primary, #FF6B35);
    box-shadow: var(--shadow-xs);
}

.landing-mobile-lang-switcher .mobile-lang-btn .lang-flag {
    font-size: var(--text-base);
}