/* ===================================
   CSS 變量定義 - 奶茶色系
   =================================== */
:root {
    /* 主色調 */
    --primary-bg: rgba(245, 240, 232, 0.95);
    --secondary-bg: rgba(250, 245, 237, 0.9);
    --accent-bg: rgba(238, 217, 196, 0.8);
    --hover-bg: rgba(252, 247, 239, 0.95);

    /* 邊框顏色 */
    --border-light: rgba(180, 150, 120, 0.3);
    --border-medium: rgba(180, 150, 120, 0.4);
    --border-focus: rgba(160, 82, 45, 0.6);

    /* 文字顏色 */
    --text-primary: #2d1810;
    --text-secondary: #4a3728;
    --text-label: #5d4037;
    --text-muted: #6d5a47;

    /* 按鈕顏色 */
    --btn-primary: linear-gradient(135deg, #8b4513 0%, #a0522d 100%);
    --btn-hover: linear-gradient(135deg, #5d4037 0%, #8b4513 100%);

    /* 陰影 */
    --shadow-light: 0 4px 20px rgba(139, 115, 85, 0.08);
    --shadow-medium: 0 8px 30px rgba(160, 82, 45, 0.12);
    --shadow-button: 0 2px 8px rgba(139, 69, 19, 0.3);

    /* 間距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-xxl: 2.5rem;

    /* 圓角 */
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
}

/* ===================================
   基礎佈局 - 響應式容器
   =================================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* 卡片容器 */
.cards-container {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
}

.cards-container .card {
    flex: 1;
    min-width: 300px;
}

/* ===================================
   卡片樣式 - 響應式版本
   =================================== */
.card {
    background: var(--primary-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-light);
    overflow: hidden;
    transition: all 0.3s ease;
    animation: fadeInUp 0.6s ease-out;
    flex: 1;
    min-width: 0;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
    border-color: var(--border-focus);
}

.card-body {
    padding: var(--spacing-xxl);
    height: 100%;
    display: flex;
    flex-direction: column;
}

.card-header {
    background: var(--secondary-bg);
    border-bottom: 1px solid var(--border-light);
    padding: var(--spacing-lg);
    font-weight: 600;
    color: var(--text-label);
    flex-shrink: 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* ===================================
   標題樣式
   =================================== */
h2 {
    color: var(--text-primary);
    font-weight: 700;
    margin-bottom: var(--spacing-xl);
    text-align: center;
    font-size: 1.75rem;
}

h5 {
    color: var(--text-label);
    font-weight: 600;
    margin: 0;
}

/* ===================================
   表單元素樣式
   =================================== */
.form-label {
    font-weight: 600;
    color: var(--text-label);
    margin-bottom: var(--spacing-sm);
    font-size: 0.95rem;
}

.form-select,
.form-control {
    border: 2px solid var(--border-light);
    border-radius: var(--radius-md);
    padding: 0.75rem var(--spacing-md);
    font-size: 1rem;
    background: var(--secondary-bg);
    transition: all 0.2s ease;
    color: var(--text-secondary);
    max-width: 100%;
    width: 100%;
    box-sizing: border-box;
}

.form-select:focus,
.form-control:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(160, 82, 45, 0.1);
    outline: none;
    background: var(--hover-bg);
}

.form-select:hover:not(:focus),
.form-control:hover:not(:focus) {
    border-color: var(--border-medium);
    background: var(--hover-bg);
}

#outputValue {
    background: var(--accent-bg);
    font-weight: 600;
    color: var(--text-secondary);
    cursor: default;
}

/* ===================================
   輸入群組和單位顯示
   =================================== */
.input-with-unit {
    display: flex;
    position: relative;
}

.input-with-unit .form-control {
    flex: 1;
    border-top-right-radius: 0;
    border-bottom-right-radius: 0;
    border-right: none;
    min-width: 0;
}

.unit-display {
    background: rgba(232, 221, 212, 0.8);
    border: 2px solid var(--border-light);
    border-left: none;
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.9rem;
    padding: 0.75rem var(--spacing-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    border-top-right-radius: var(--radius-md);
    border-bottom-right-radius: var(--radius-md);
    width: 80px;
    flex-shrink: 0;
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
    transition: all 0.2s ease;
}

.input-with-unit .form-control:focus+.unit-display {
    border-color: var(--border-focus);
    background: rgba(240, 229, 220, 0.9);
    color: var(--text-secondary);
}

.output-with-unit .unit-display {
    background: rgba(218, 165, 32, 0.15);
    color: #8b4513;
}

/* ===================================
   按鈕樣式
   =================================== */
.btn {
    border-radius: var(--radius-md);
    padding: 0.75rem var(--spacing-xl);
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.2s ease;
    border: none;
    min-width: 140px;
}

.btn-secondary {
    background: var(--btn-primary);
    color: white;
    box-shadow: var(--shadow-button);
}

.btn-secondary:hover {
    background: var(--btn-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(139, 69, 19, 0.4);
    color: white;
}

.btn-secondary:active {
    transform: translateY(0);
}

/* ===================================
   下拉選單功能樣式
   =================================== */
.dropdown-search {
    position: relative;
}

.dropdown-search .dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 1050;
    width: 100%;
    max-height: 300px;
    overflow-y: auto;

    background: #f8f6f3 !important;
    backdrop-filter: blur(10px);

    border: 2px solid #d4b896 !important;
    border-radius: var(--radius-md);
    box-shadow:
        0 8px 25px rgba(0, 0, 0, 0.15),
        0 4px 10px rgba(0, 0, 0, 0.1),
        0 0 0 1px rgba(212, 184, 150, 0.2) !important;

    margin-top: 2px;
    display: none;
}

.dropdown-search .btn.show {
    border-color: var(--border-focus) !important;
    box-shadow: 0 0 0 3px rgba(160, 82, 45, 0.1) !important;
    background: var(--hover-bg) !important;
}

.dropdown-search .unit-option {
    background: transparent !important;
    color: var(--text-secondary) !important;
}

.dropdown-search .unit-option:hover {
    background: var(--hover-bg) !important;
    color: var(--text-primary) !important;
}

.dropdown-search .category-header {
    background: var(--accent-bg) !important;
    color: var(--text-label) !important;
}

.dropdown-search .search-input {
    background: var(--secondary-bg) !important;
    border-bottom: 1px solid var(--border-light) !important;
    position: sticky !important;
    top: 0 !important;
    z-index: 1051 !important;
}

.dropdown-search .btn {
    background: var(--secondary-bg);
    border: 2px solid var(--border-light);
    color: var(--text-secondary);
    text-align: left;
    min-width: auto;
}

.dropdown-search .btn:hover {
    background: var(--hover-bg);
    border-color: var(--border-medium);
    transform: none;
    box-shadow: none;
}

.unit-option {
    cursor: pointer;
    padding: var(--spacing-md) var(--spacing-lg);
    border-bottom: 1px solid rgba(180, 150, 120, 0.1);
    color: var(--text-secondary);
    transition: all 0.2s ease;
}

.unit-option:hover {
    background: var(--hover-bg);
    color: var(--text-primary);
}

.unit-option.selected {
    background: var(--border-focus);
    color: white;
}

.category-header {
    background: var(--accent-bg);
    font-weight: bold;
    padding: var(--spacing-md) var(--spacing-lg);
    color: var(--text-label);
    font-size: 0.875rem;
    border-bottom: 1px solid var(--border-light);
}

/* ===================================
   搜索結果樣式
   =================================== */
.search-results {
    max-height: 300px;
    overflow-y: auto;
}

.search-results .unit-option {
    padding: var(--spacing-md);
    border-bottom: 1px solid rgba(180, 150, 120, 0.1);
}

.search-results .unit-option:last-child {
    border-bottom: none;
}

/* ===================================
   公式顯示樣式
   =================================== */
.formula-step {
    background: var(--secondary-bg);
    border-left: 4px solid var(--border-focus);
    padding: var(--spacing-lg);
    margin: var(--spacing-md) 0;
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
}

.formula-step code {
    background: var(--accent-bg);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: 'Courier New', monospace;
}

/* ===================================
   交換按鈕間距
   =================================== */
.mt-4 {
    margin-top: 2rem;
}

/* ===================================
   轉換列表樣式
   =================================== */
.conversion-list {
    max-height: 400px;
    overflow-y: auto;
    padding: var(--spacing-md) 0;
}

.conversion-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    margin: var(--spacing-xs) 0;
    background: var(--secondary-bg);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-light);
    transition: all 0.2s ease;
}

.conversion-item:hover {
    background: var(--hover-bg);
    border-color: var(--border-medium);
}

.conversion-item.selected {
    background: var(--accent-bg);
    border-color: var(--border-focus);
    font-weight: 600;
}

.unit-name {
    font-weight: 500;
    color: var(--text-secondary);
}

.unit-symbol {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-left: var(--spacing-sm);
}

.unit-value {
    font-family: 'Courier New', monospace;
    color: var(--text-primary);
    font-weight: 600;
}

/* ===================================
   動畫效果
   =================================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

[data-i18n],
[data-i18n-placeholder] {
    transition: opacity 0.2s ease;
}

.language-switching [data-i18n],
.language-switching [data-i18n-placeholder] {
    opacity: 0.7;
}

/* ===================================
   計算機樣式
   =================================== */
.calculator-btn {
    background: var(--secondary-bg);
    border: 1px solid var(--border-light);
    color: var(--text-secondary);
    font-size: 0.85rem;
    padding: 0.4rem 0.8rem;
    border-radius: var(--radius-sm);
    transition: all 0.2s ease;
}

.calculator-btn:hover {
    background: var(--hover-bg);
    border-color: var(--border-medium);
    color: var(--text-primary);
}

.calculator-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.calculator-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
}

.calculator-container {
    position: relative;
    background: var(--primary-bg);
    border: 1px solid var(--border-medium);
    border-radius: var(--radius-xl);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    width: 340px;
    max-width: 90vw;
    max-height: 90vh;
    overflow: hidden;
}

.calculator-header {
    background: var(--secondary-bg);
    border-bottom: 1px solid var(--border-light);
    padding: var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.calculator-header h5 {
    margin: 0;
    color: var(--text-label);
    font-weight: 600;
}

.calculator-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0.25rem;
    border-radius: var(--radius-sm);
    transition: all 0.2s ease;
}

.calculator-close:hover {
    background: var(--hover-bg);
    color: var(--text-primary);
}

.calculator-body {
    padding: 16px;
}

.calculator-display {
    margin-bottom: 16px;
    padding: 0 4px;
}

.calculator-display input {
    width: 100%;
    padding: 12px 16px;
    font-size: 1.4rem;
    text-align: right;
    background: var(--accent-bg);
    border: 2px solid var(--border-light);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-weight: 600;
    font-family: 'Courier New', monospace;
    box-sizing: border-box;
    max-width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
}

.calculator-buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
    margin-bottom: var(--spacing-lg);
    padding: 0 4px;
}

.calc-btn {
    background: var(--secondary-bg);
    border: 1px solid var(--border-light);
    color: var(--text-secondary);
    font-size: 1.1rem;
    font-weight: 600;
    padding: 12px 8px;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
    min-height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-sizing: border-box;
}

.calc-btn:hover {
    background: var(--hover-bg);
    border-color: var(--border-medium);
    color: var(--text-primary);
    transform: translateY(-1px);
}

.calc-btn:active {
    transform: translateY(0);
}

.calc-number {
    background: var(--primary-bg);
}

.calc-operator {
    background: var(--accent-bg);
    color: var(--text-primary);
    font-weight: 700;
}

.calc-clear {
    background: rgba(220, 38, 38, 0.1);
    color: #dc2626;
    border-color: rgba(220, 38, 38, 0.3);
}

.calc-clear:hover {
    background: rgba(220, 38, 38, 0.2);
    border-color: rgba(220, 38, 38, 0.5);
}

.calc-equals {
    background: var(--btn-primary);
    color: white;
    border-color: transparent;
}

.calc-equals:hover {
    background: var(--btn-hover);
    color: white;
}

.calc-zero {
    grid-column: span 2;
}

.calculator-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: space-between;
}

.calculator-actions .btn {
    flex: 1;
    min-width: 0;
}

/* 計算機開啟時的body樣式 */
body.calculator-open {
    overflow: hidden;
}

/* ===================================
   響應式設計 - 手機版
   =================================== */
@media (max-width: 768px) {
    .cards-container {
        flex-direction: column;
    }

    .cards-container .card {
        min-width: auto;
    }

    .card-header {
        flex-direction: column;
        gap: var(--spacing-md);
        align-items: stretch;
    }

    .card-header .form-select {
        width: 100% !important;
        min-width: auto !important;
    }

    .calculator-container {
        width: calc(100vw - 32px);
        max-width: 400px;
        margin: var(--spacing-md);
    }

    .calc-btn {
        padding: 12px 8px;
        min-height: 48px;
        font-size: 1.1rem;
    }

    .calculator-display input {
        font-size: 1.3rem;
        padding: 14px 16px;
    }
}