/* 全域樣式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --milk-tea-lightest: #F7EFE6;
    --milk-tea-light: #E8DCCF;
    --milk-tea-medium: #D2B48C;
    --milk-tea-dark: #8B7355;
    --milk-tea-darkest: #4A3C2B;
    --text-primary: #4A3C2B;
    --text-secondary: #6B5E4D;
    --text-on-dark: #FFFFFF;
    --bg-primary: #FAF4EC;
    --bg-secondary: #F5E8DA;
    --bg-footer: #E8DCCF;

    /* spacing scale */
    --spacing-xs: 6px;
    --spacing-sm: 10px;
    --spacing-md: 20px;
    --spacing-lg: 30px;

    /* radius scale */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;

    /* shadow presets */
    --shadow-sm: 0 3px 10px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 5px 15px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.2);
}

body {
    font-family: 'Microsoft JhengHei', 'PingFang TC', 'Noto Sans TC', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
}

/* 導航列 */
.navbar {
    background: var(--bg-secondary);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 10px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand h2 { color: var(--text-primary); font-size: 1.4em; letter-spacing: 0.5px; }
.nav-brand .brand-link { display: flex; align-items: center; }
.nav-brand img { height: auto; max-height: 120px; width: auto; display: block; object-fit: contain; }
@media (max-width: 640px) { .nav-brand img { height: auto; max-height: 56px; } }

.nav-menu {
    display: flex;
    list-style: none;
    gap: 24px;
    align-items: center;
    flex-wrap: wrap;
    row-gap: 8px;
    justify-content: center;
    margin: 0 auto;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-primary); /* Darkest milk tea for general link text */
    font-weight: 500;
    padding: 8px 16px;
    border-radius: 5px;
    transition: all 0.3s;
    white-space: nowrap;
}

.nav-menu a:hover,
.nav-menu a.active {
    background: var(--milk-tea-medium);
    color: var(--text-on-dark);
}

.nav-menu a.disabled {
    color: var(--milk-tea-medium); /* Medium milk tea for disabled links */
    cursor: not-allowed;
}

.nav-menu a.disabled:hover {
    background: transparent;
    color: var(--milk-tea-medium); /* Medium milk tea for disabled links */
}

/* Dropdown Menu */
.nav-item-dropdown {
    position: relative;
}

.dropdown-toggle {
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 4px;
}

.dropdown-toggle::after {
    content: '▼';
    font-size: 0.7em;
    transition: transform 0.3s;
}

.nav-item-dropdown:hover .dropdown-toggle::after {
    transform: rotate(180deg);
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background: var(--bg-secondary);
    min-width: 180px;
    box-shadow: var(--shadow-md);
    border-radius: var(--radius-sm);
    padding: 8px 0;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all 0.3s;
    list-style: none;
    z-index: 1001;
}

.nav-item-dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu li a {
    display: block;
    padding: 8px 16px;
    white-space: nowrap;
    border-radius: 0;
}

.dropdown-menu li a:hover {
    background: var(--milk-tea-medium);
    color: var(--text-on-dark);
}

/* 容器 */
.nav-container {
    max-width: 1600px;
    margin: 0 auto;
    padding: 10px 20px;
    display: grid;
    grid-template-columns: auto auto 1fr auto;
    align-items: center;
    column-gap: 12px;
}

/* 手機漢堡選單 */
.nav-toggle {
    display: none;
    width: 40px;
    height: 40px;
    border: none;
    border-radius: var(--radius-md);
    background: transparent;
    color: var(--text-primary);
    font-size: 1.8em;
    line-height: 1;
    cursor: pointer;
}

.nav-menu#primary-menu {
    list-style: none;
}

/* 右側動作區（手機版顯示在 logo 右側） */
.nav-actions { display: flex; align-items: center; gap: 8px; }
.nav-actions .btn-secondary, .nav-actions .btn-primary { padding: 6px 10px; font-size: 14px; }
.nav-actions { flex-wrap: nowrap; }
.nav-actions .register-btn { white-space: nowrap; }
.device-select { padding: 6px 10px; border: 1px solid var(--milk-tea-medium); border-radius: var(--radius-md); background: var(--milk-tea-light); color: var(--text-primary); }

/* 區塊標題 */
.section-title {
    font-size: 2em;
    color: var(--text-primary);
    margin-bottom: 20px;
    text-align: center;
}

/* 通用頁首區塊 */
.page-header {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    padding: calc(var(--spacing-lg) + var(--spacing-sm));
    text-align: center;
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-lg);
}

.page-header h1 {
    font-size: 2.4em;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1.05em;
}

/* 頁尾 */
.footer {
    background: var(--bg-footer);
    color: var(--text-primary);
    padding: 30px 20px;
    margin-top: 50px;
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
    text-align: center;
}

.footer-content p {
    margin: 5px 0;
    opacity: 0.9;
}

.footer-content p a {
    color: var(--text-primary); /* Darkest milk tea for footer links */
    text-decoration: none;
}

.footer-content p a:hover {
    text-decoration: underline;
}

/* 通用按鈕樣式 */
.btn-primary { padding: 12px 28px; background: var(--milk-tea-medium); color: var(--text-on-dark); border: none; border-radius: var(--radius-md); font-size: 1em; font-weight: 700; cursor: pointer; transition: all 0.3s; }

.btn-primary:hover { background: var(--milk-tea-dark); box-shadow: var(--shadow-sm); transform: translateY(-2px); }

.btn-secondary { padding: 10px 16px; background: var(--milk-tea-light); color: var(--text-primary); border: 1px solid var(--milk-tea-medium); border-radius: var(--radius-md); font-size: 0.95em; font-weight: 600; cursor: pointer; transition: all 0.3s; }

.btn-secondary:hover { background: var(--milk-tea-medium); color: var(--text-on-dark); box-shadow: var(--shadow-sm); }

/* 版本切換按鈕 */
.device-toggle { display: flex; gap: 8px; align-items: center; }
.device-toggle .btn-secondary.active { background: var(--milk-tea-medium); color: var(--text-on-dark); }

/* 響應式設計 */
@media (max-width: 768px) {
    .nav-container { display: grid; grid-template-columns: auto 1fr auto; height: 64px; padding: 10px 16px; }
    .nav-actions { justify-self: start; }
    .nav-brand .brand-link { min-height: 56px; display: flex; align-items: center; }
    .nav-brand img { max-height: 56px; }

    .nav-toggle {
        display: block;
    }

    .nav-menu {
        display: none;
        position: absolute;
        left: 0;
        right: 0;
        top: 64px;
        background: var(--bg-secondary);
        padding: 12px 16px;
        flex-direction: column;
        gap: 8px;
        box-shadow: var(--shadow-md);
        margin: 0;
    }

    .navbar.open .nav-menu {
        display: flex;
    }
}

/* 無障礙：隱形但可聚焦元素 */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Support Modal (Global) */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,0.6);
    backdrop-filter: blur(2px);
}

.modal-content {
    background-color: #fff;
    margin: 5% auto;
    padding: 24px;
    border: 1px solid var(--milk-tea-medium);
    border-radius: var(--radius-md);
    width: 90%;
    max-width: 600px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    text-align: center;
    position: relative;
    animation: modalFadeIn 0.3s;
}

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

.close-btn {
    color: var(--text-secondary);
    float: right;
    font-size: 28px;
    font-weight: bold;
    position: absolute;
    right: 16px;
    top: 8px;
    cursor: pointer;
    transition: color 0.2s;
}

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

.video-container {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 aspect ratio */
    height: 0;
    margin: 20px 0;
    border-radius: var(--radius-sm);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.modal-content h3 {
    margin-top: 0;
    color: var(--text-primary);
    padding-right: 20px;
}

.modal-content p {
    color: var(--text-primary);
    margin-bottom: 0;
    line-height: 1.6;
}