:root {
    --primary-color: #007AFF;
    --bg-gray: #f2f2f7;
}

body {
    font-family: -apple-system, system-ui, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: #ffffff;
    margin: 0;
    padding: 20px;
    display: flex;
    justify-content: center;
}

.container {
    width: 100%;
    max-width: 500px;
}

h2 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 5px;
}

.subtitle {
    color: #8e8e93;
    font-size: 14px;
    margin-bottom: 25px;
}

.input-group {
    margin-bottom: 20px;
}

label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    font-size: 14px;
    color: #333;
}

input[type="text"], 
input[type="file"], 
select {
    width: 100%;
    padding: 14px;
    border: 1px solid #e5e5ea;
    border-radius: 12px;
    box-sizing: border-box;
    font-size: 16px;
    background: var(--bg-gray);
    appearance: none;
}

/* 顏色選擇器 */
.color-row {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 10px;
}

input[type="color"] {
    border: none;
    width: 50px;
    height: 50px;
    cursor: pointer;
    background: none;
}

.slider-box {
    background: var(--bg-gray);
    padding: 15px;
    border-radius: 12px;
    margin-top: 10px;
}

.slider-row {
    display: flex;
    align-items: center;
    margin-bottom: 12px;
}

.slider-row label {
    margin-bottom: 0;
    width: 70px;
    flex-shrink: 0;
    font-size: 13px;
}

input[type="range"] {
    flex-grow: 1;
    margin-right: 10px;
    accent-color: var(--primary-color);
}

.val-display {
    width: 45px;
    font-size: 12px;
    color: #666;
    text-align: right;
    font-variant-numeric: tabular-nums;
}

button {
    background: var(--primary-color);
    color: white;
    border: none;
    width: 100%;
    padding: 16px;
    border-radius: 14px;
    font-size: 17px;
    font-weight: 600;
    margin-top: 20px;
    transition: background 0.2s;
    cursor: pointer;
}

button:disabled {
    background: #d1d1d6;
    cursor: not-allowed;
}

#statusDisplay {
    margin-top: 20px;
    font-size: 14px;
    color: #007AFF;
    text-align: center;
    font-weight: 500;
    min-height: 20px;
}

.preview-box {
    margin-top: 30px;
    border-top: 1px solid #eee;
    padding-top: 20px;
    display: none;
}

video {
    width: 100%;
    border-radius: 12px;
    background: #000;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.download-link {
    display: block;
    text-align: center;
    margin-top: 15px;
    color: #007AFF;
    text-decoration: none;
    font-weight: 600;
    padding: 10px;
}