:root {
    --c-primary: #0f4c81;
    --c-primary-dark: #0b3a64;
    --c-accent: #a4d65e;
    --c-text: #1f2937;
    --c-muted: #6b7280;
    --c-bg: #f8fafc;
    --c-surface: #ffffff;
    --c-border: #e5e7eb;
    --c-error: #b91c1c;
    --c-error-bg: #fef2f2;
    --radius: 10px;
    --shadow: 0 1px 2px rgba(15, 23, 42, .04), 0 4px 16px rgba(15, 23, 42, .06);
    --maxw: 960px;
}

* { box-sizing: border-box; }

html, body {
    margin: 0;
    padding: 0;
    background: var(--c-bg);
    color: var(--c-text);
    font: 16px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

a { color: var(--c-primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.site-header {
    background: var(--c-surface);
    border-bottom: 1px solid var(--c-border);
    position: sticky;
    top: 0;
    z-index: 10;
}

.header-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 12px 20px;
}

.brand img {
    height: 40px;
    width: auto;
    display: block;
}

.site-nav {
    display: flex;
    gap: 6px;
}

.site-nav a {
    padding: 8px 14px;
    border-radius: var(--radius);
    color: var(--c-text);
    font-weight: 600;
    font-size: 0.95rem;
}

.site-nav a:hover {
    background: var(--c-bg);
    text-decoration: none;
}

.site-nav a.is-active {
    background: var(--c-primary);
    color: #fff;
}

/* Hero / form */
main.container {
    padding-top: 32px;
    padding-bottom: 48px;
}

.hero {
    text-align: center;
    margin-bottom: 28px;
}

.hero h1 {
    font-size: clamp(1.8rem, 3vw, 2.4rem);
    margin: 0 0 6px;
    color: var(--c-primary-dark);
    line-height: 1.15;
}

.hero-subtitle {
    font-size: clamp(1.05rem, 1.6vw, 1.3rem);
    color: var(--c-text);
    font-weight: 500;
    margin: 0 0 12px;
    line-height: 1.3;
}

.hero-desc {
    color: var(--c-muted);
    margin: 0;
    font-size: 1.02rem;
}

.upload-card {
    background: var(--c-surface);
    border: 1px solid var(--c-border);
    border-radius: var(--radius);
    padding: 28px;
    box-shadow: var(--shadow);
    margin-bottom: 28px;
}

.dropzone {
    display: block;
    position: relative;
    border: 2px dashed #c7d2da;
    border-radius: var(--radius);
    padding: 40px 20px;
    text-align: center;
    cursor: pointer;
    transition: border-color .15s ease, background .15s ease;
}

.dropzone:hover,
.dropzone.is-dragover {
    border-color: var(--c-primary);
    background: #f1f6fb;
}

.dropzone input[type="file"] {
    position: absolute;
    inset: 0;
    opacity: 0;
    cursor: pointer;
}

.dropzone-icon {
    width: 48px;
    height: 48px;
    margin: 0 auto 10px;
    color: var(--c-primary);
}

.dropzone strong {
    display: block;
    font-size: 1.1rem;
    margin-bottom: 4px;
}

.dropzone small {
    color: var(--c-muted);
}

.file-name {
    margin-top: 12px;
    font-weight: 600;
    color: var(--c-primary-dark);
    word-break: break-all;
}

.btn {
    display: inline-block;
    background: var(--c-primary);
    color: #fff;
    border: 0;
    padding: 12px 22px;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background .15s ease;
    margin-top: 18px;
}

.form-actions {
    display: flex;
    justify-content: center;
    margin-top: 4px;
}

.btn:hover { background: var(--c-primary-dark); }
.btn:disabled { background: #9ca3af; cursor: not-allowed; }

.privacy-note {
    text-align: center;
    color: var(--c-muted);
    font-size: 0.9rem;
    margin: 14px 0 0;
}

.alert {
    padding: 12px 16px;
    border-radius: var(--radius);
    margin-bottom: 20px;
    border: 1px solid transparent;
}

.alert-error {
    background: var(--c-error-bg);
    color: var(--c-error);
    border-color: #fecaca;
}

.is-hidden {
    display: none !important;
}

/* Content */
.content {
    background: var(--c-surface);
    border: 1px solid var(--c-border);
    border-radius: var(--radius);
    padding: 28px 32px;
    box-shadow: var(--shadow);
}

.content h2 {
    color: var(--c-primary-dark);
    margin-top: 1.6em;
    font-size: 1.25rem;
}

.content h2:first-child { margin-top: 0; }

.content p, .content li {
    color: #2b3440;
}

.content ul,
.content ol {
    padding-left: 1.2em;
}

.content details {
    border: 1px solid var(--c-border);
    border-radius: var(--radius);
    padding: 12px 16px;
    margin: 10px 0;
    background: #fcfdfe;
}

.content details[open] {
    border-color: #c8d6e3;
    background: #f7fbff;
}

.content details summary {
    cursor: pointer;
    font-weight: 600;
    color: var(--c-primary-dark);
    list-style: none;
    padding-right: 24px;
    position: relative;
}

.content details summary::-webkit-details-marker { display: none; }

.content details summary::after {
    content: "+";
    position: absolute;
    right: 4px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.2em;
    color: var(--c-muted);
    transition: transform .15s ease;
}

.content details[open] summary::after {
    content: "−";
}

.content details p {
    margin: 10px 0 0;
    color: #2b3440;
}

.content code {
    background: #eef2f7;
    padding: 1px 6px;
    border-radius: 4px;
    font-size: 0.92em;
}

/* Footer */
.site-footer {
    border-top: 1px solid var(--c-border);
    background: var(--c-surface);
    padding: 22px 0;
    text-align: center;
    color: var(--c-muted);
    font-size: 0.92rem;
}

.site-footer a { color: var(--c-primary); }

.site-footer .container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

.footer-credit {
    color: var(--c-muted);
}

.footer-brand {
    display: inline-block;
    line-height: 0;
    transition: opacity .15s ease;
}

.footer-brand:hover { opacity: 0.8; }

.footer-brand img {
    height: 28px;
    width: auto;
    display: block;
}

/* Responsive tweaks */
@media (max-width: 640px) {
    .header-row { padding: 10px 16px; }
    .brand img { height: 32px; }
    .site-nav a { padding: 6px 10px; font-size: 0.9rem; }
    .upload-card, .content { padding: 20px; }
    .dropzone { padding: 28px 14px; }
}