/* --- 全域設定與變數 --- */
:root {
    --primary-color-dark: #6366f1;
    --background-color-dark: #1a202c;
    --card-background-dark: #2d3748;
    --text-color-dark: #e2e8f0;
    --heading-color-dark: #ffffff;
    
    --primary-color-light: #4f46e5;
    --background-color-light: #f7fafc;
    --card-background-light: #ffffff;
    --text-color-light: #4a5568;
    --heading-color-light: #1a202c;

    --font-primary: 'Roboto', 'Noto Sans TC', sans-serif;
    --font-secondary: 'Noto Sans TC', sans-serif;
}

/* --- 漸進載入動畫 --- */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* --- 基礎樣式 (預設為深色模式) --- */
body {
    background-color: var(--background-color-dark);
    color: var(--text-color-dark);
    font-family: var(--font-primary);
    line-height: 1.6;
    margin: 0;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 2rem;
    animation: fadeIn 0.8s ease-out forwards;
}

section {
    padding: 4rem 0;
}

h1, h2, h3 {
    font-family: var(--font-secondary);
    color: var(--heading-color-dark);
    margin-top: 0;
}

a {
    color: var(--primary-color-dark);
    text-decoration: none;
    transition: color 0.3s;
}

a:hover {
    color: #a5b4fc;
}

/* --- 導覽列 --- */
header {
    background-color: var(--card-background-dark);
    padding: 1rem 2rem;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 10px rgba(0,0,0,0.5);
    transition: background-color 0.3s;
}

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

nav .logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--heading-color-dark);
}

nav ul {
    list-style: none;
    display: flex;
    gap: 2rem;
    margin: 0;
    padding: 0;
}

#theme-toggle {
    background-color: var(--primary-color-dark);
    color: #fff;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s;
}

#theme-toggle:hover {
    background-color: #4338ca;
    transform: scale(1.05);
}

/* --- 英雄區塊 --- */
.hero {
    text-align: center;
    padding: 6rem 1rem;
    animation: fadeIn 0.8s ease-out forwards;
}

.cta-button {
    display: inline-block;
    background-color: var(--primary-color-dark);
    color: #fff;
    padding: 0.8rem 1.5rem;
    border-radius: 5px;
    margin-top: 1rem;
    transition: background-color 0.3s, transform 0.2s;
}

.cta-button:hover {
    background-color: #4338ca;
    transform: translateY(-2px);
    color: #fff; /* 確保懸停時文字顏色不變 */
}

/* --- 專案區塊 --- */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.project-card {
    background-color: var(--card-background-dark);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.3);
    padding: 1.5rem;
    transition: transform 0.3s, box-shadow 0.3s, background-color 0.3s;
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 20px rgba(0,0,0,0.4);
}

.project-card img {
    width: 100%;
    height: auto;
    display: block;
    margin-bottom: 1rem;
    border-radius: 4px;
}

/* --- 聯絡與頁尾 --- */
.contact-links, .social-links {
    display: flex;
    gap: 1.5rem;
    margin-top: 1rem;
    flex-wrap: wrap;
}

.contact-links a, .social-links a {
    font-size: 1.2rem;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.social-links a {
    font-size: 1.5rem;
}

footer {
    text-align: center;
    padding: 2rem;
    background-color: var(--card-background-dark);
    margin-top: 4rem;
    transition: background-color 0.3s;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 960px;
    margin: 0 auto;
}

/* --- 淺色模式 --- */
body.light-mode {
    background-color: var(--background-color-light);
    color: var(--text-color-light);
}

body.light-mode h1,
body.light-mode h2,
body.light-mode h3 {
    color: var(--heading-color-light);
}

body.light-mode a {
    color: var(--primary-color-light);
}

body.light-mode a:hover {
    color: #6366f1;
}

body.light-mode header,
body.light-mode footer {
    background-color: #e2e8f0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

body.light-mode nav .logo {
    color: var(--heading-color-light);
}

body.light-mode #theme-toggle,
body.light-mode .cta-button {
    background-color: var(--primary-color-light);
    color: #fff; /* <-- 【修正】在這裡明確指定按鈕文字顏色為白色 */
}

body.light-mode #theme-toggle:hover,
body.light-mode .cta-button:hover {
    background-color: #3730a3;
    color: #fff; /* <-- 【修正】確保懸停時文字顏色依然為白色 */
}

body.light-mode .project-card {
    background-color: var(--card-background-light);
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

body.light-mode .project-card:hover {
    box-shadow: 0 12px 20px rgba(0,0,0,0.1);
}