:root {
    --bg-color: #fafafa;
    --text-color: #111;
    --card-bg: #fff;
    --button-bg: #111;
    --button-text: #fff;
    --button-hover: #333;
}

body.dark-mode {
    --bg-color: #111;
    --text-color: #fafafa;
    --card-bg: #1a1a1a;
    --button-bg: #f5a623;
    --button-text: #111;
    --button-hover: #e6a500;
}

* {
    box-sizing: border-box;
}

body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 0;
}

header,
main,
footer {
    max-width: 720px;
    margin: auto;
    padding: 20px;
}

/* Polished Header */
header {
    background: linear-gradient(to right, #4a90e2, #50c878);
    color: #fff;
    text-align: center;
    padding: 40px 20px;
    border-radius: 0 0 12px 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
}

header .subtitle {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: #f0f0f0;
}

#darkModeToggle {
    margin-left: 10px;
    padding: 6px 10px;
    font-size: 14px;
    cursor: pointer;
    background: #fff;
    color: #4a90e2;
    border: 1px solid #aaa;
    border-radius: 4px;
    transition: all 0.2s ease;
}

#darkModeToggle:hover {
    background: #e0e0e0;
}

body.dark-mode #darkModeToggle {
    background: #f5a623;
    color: #111;
}

h1 {
    font-size: 36px;
    margin-bottom: 8px;
}

.subtitle {
    font-size: 18px;
    color: #555;
    margin-bottom: 12px;
}

.drop-zone {
    border: 2px dashed #aaa;
    border-radius: 10px;
    padding: 40px 20px;
    text-align: center;
    cursor: pointer;
    background: var(--card-bg);
    margin-bottom: 20px;
    font-size: 16px;
    transition: border-color 0.2s ease, background 0.2s ease;
}

.drop-zone.dragover {
    border-color: #111;
}

.page-size-selector {
    margin-bottom: 20px;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 10px;
}

#fileName {
    padding: 6px;
    border-radius: 4px;
    border: 1px solid #aaa;
}

#preview-strip {
    display: flex;
    overflow-x: auto;
    gap: 10px;
    margin-bottom: 10px;
    padding-bottom: 5px;
}

#preview-strip img {
    height: 60px;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: grab;
}

#preview-strip img:active {
    cursor: grabbing;
}

#preview-strip img+img {
    margin-left: 10px;
}

button {
    margin-top: 16px;
    padding: 14px 22px;
    font-size: 16px;
    background: var(--button-bg);
    color: var(--button-text);
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
}

button:hover {
    background: var(--button-hover);
}

h2 {
    font-size: 24px;
    margin-top: 40px;
    margin-bottom: 12px;
}

ol,
ul {
    margin-left: 20px;
    margin-bottom: 20px;
}

/* Polished Footer */
footer {
    text-align: center;
    color: #777;
    font-size: 14px;
    padding: 20px 0;
    background-color: #f2f2f2;
    border-top: 1px solid #ddd;
}

/* Mini blog / SEO sections */
.blog-seo {
    background-color: #f9f9f9;
    border-left: 4px solid #4a90e2;
    padding: 20px;
    margin: 30px 0;
    border-radius: 6px;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.blog-seo h2 {
    margin-top: 0;
    color: #333;
    font-size: 1.5rem;
}

.blog-seo p {
    margin-bottom: 0;
    color: #555;
    line-height: 1.6;
}