/* 全域變數與基礎設定 */
:root {
    --primary-color: #4a90e2;
    --primary-hover: #357abd;
    --bg-color: #f4f7f6;
    --card-bg: #ffffff;
    --text-main: #333333;
    --text-muted: #666666;
    --border-color: #e0e0e0;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: "Helvetica Neue", Helvetica, Arial, "PingFang TC", "微軟正黑體", sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
}

/* 導覽列 */
.navbar {
    background-color: var(--primary-color);
    color: white;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 15px 20px;
}

.nav-container h1 {
    font-size: 1.5rem;
    margin: 0;
}

/* 主容器 */
.container {
    max-width: 800px;
    margin: 30px auto;
    padding: 0 20px;
}

/* 卡片共用樣式 */
.card {
    background-color: var(--card-bg);
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    padding: 25px;
    margin-bottom: 30px;
}

.section-title {
    font-size: 1.2rem;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--border-color);
    color: var(--primary-color);
}

/* 表單區塊 */
.form-group {
    margin-bottom: 15px;
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: 5px;
    font-weight: bold;
    color: var(--text-muted);
}

.form-group input[type="text"] {
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 1rem;
}

.form-group input[type="text"]:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group input[type="file"] {
    padding: 10px 0;
}

.submit-btn {
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 10px 20px;
    font-size: 1rem;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s;
    width: 100%;
    margin-top: 10px;
}

.submit-btn:hover {
    background-color: var(--primary-hover);
}

/* 留言呈現區 */
.feed-container {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.post-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 4px rgba(0,0,0,0.02);
}

.post-text {
    padding: 15px 20px;
    font-size: 1.1rem;
}

.post-image {
    width: 100%;
    max-height: 500px;
    object-fit: contain;
    background-color: #fafafa;
    border-top: 1px solid var(--border-color);
}

/* 刪除按鈕樣式 */
.post-card {
    position: relative; /* 為了讓 X 按鈕絕對定位 */
}
.delete-btn {
    position: absolute;
    top: 10px;
    right: 10px;
    background-color: rgba(255, 0, 0, 0.7);
    color: white;
    border: none;
    border-radius: 50%;
    width: 25px;
    height: 25px;
    font-size: 14px;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: background-color 0.2s;
}
.delete-btn:hover {
    background-color: rgba(255, 0, 0, 1);
}