/**
 * Image Format Converter — custom theme on top of Bootstrap 5
 */

:root {
    --ic-bg: #f4f6fb;
    --ic-surface: #ffffff;
    --ic-surface-soft: #f0f3fa;
    --ic-text: #121722;
    --ic-muted: #5c6578;
    --ic-border: rgba(18, 23, 34, 0.08);
    --ic-accent: #3d5afe;
    --ic-accent-soft: rgba(61, 90, 254, 0.12);
    --ic-accent-hover: #2f4ae8;
    --ic-shadow: 0 18px 50px rgba(18, 23, 34, 0.08);
    --ic-shadow-sm: 0 8px 24px rgba(18, 23, 34, 0.06);
    --ic-radius: 1rem;
    --ic-font: "Plus Jakarta Sans", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

[data-theme="dark"] {
    --ic-bg: #0e1117;
    --ic-surface: #161b24;
    --ic-surface-soft: #1c2330;
    --ic-text: #eef1f7;
    --ic-muted: #9aa3b5;
    --ic-border: rgba(238, 241, 247, 0.08);
    --ic-accent: #7c9bff;
    --ic-accent-soft: rgba(124, 155, 255, 0.15);
    --ic-accent-hover: #9eb6ff;
    --ic-shadow: 0 18px 50px rgba(0, 0, 0, 0.45);
    --ic-shadow-sm: 0 8px 24px rgba(0, 0, 0, 0.35);
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--ic-font);
    background: var(--ic-bg);
    color: var(--ic-text);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background 0.25s ease, color 0.25s ease;
}

.skip-link {
    position: absolute;
    left: 1rem;
    top: -100px;
    z-index: 1080;
    padding: 0.5rem 1rem;
    background: var(--ic-accent);
    color: #fff;
    border-radius: 0.5rem;
}

.skip-link:focus {
    top: 1rem;
}

.text-accent {
    color: var(--ic-accent) !important;
}

.site-header {
    background: linear-gradient(135deg, var(--ic-surface) 0%, var(--ic-surface-soft) 50%, var(--ic-surface) 100%);
    border-bottom: 1px solid var(--ic-border);
}

.hero-title {
    letter-spacing: -0.02em;
}

.hero-sub {
    max-width: 38rem;
}

.letter-spacing {
    letter-spacing: 0.12em;
}

.btn-theme-toggle {
    width: 2.75rem;
    height: 2.75rem;
    border-radius: 50%;
    border: 1px solid var(--ic-border);
    background: var(--ic-surface);
    color: var(--ic-text);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn-theme-toggle:hover {
    transform: translateY(-1px);
    box-shadow: var(--ic-shadow-sm);
}

.card-soft {
    background: var(--ic-surface);
    border: 1px solid var(--ic-border);
    box-shadow: var(--ic-shadow-sm);
}

.section-icon {
    display: inline-flex;
    width: 2rem;
    height: 2rem;
    align-items: center;
    justify-content: center;
    border-radius: 0.5rem;
    background: var(--ic-accent-soft);
    color: var(--ic-accent);
    font-size: 1rem;
}

.info-banner {
    background: linear-gradient(120deg, var(--ic-accent-soft), transparent);
    border: 1px solid var(--ic-border);
}

.info-banner-icon {
    font-size: 1.5rem;
    color: var(--ic-accent);
}

.dropzone {
    border: 2px dashed rgba(61, 90, 254, 0.35);
    background: linear-gradient(180deg, var(--ic-surface-soft), var(--ic-surface));
    cursor: pointer;
    transition: border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.dropzone:hover,
.dropzone:focus {
    outline: none;
    border-color: var(--ic-accent);
    box-shadow: 0 0 0 4px var(--ic-accent-soft);
}

.dropzone.dragover {
    border-color: var(--ic-accent-hover);
    transform: scale(1.005);
}

.dropzone-icon {
    font-size: 2.5rem;
    color: var(--ic-accent);
}

.upload-progress {
    position: absolute;
    inset: 0;
    background: var(--ic-surface);
    border: 1px solid var(--ic-border);
}

.progress-thin {
    height: 0.35rem;
    border-radius: 50rem;
    background: var(--ic-surface-soft);
}

.progress-thin .progress-bar {
    background: linear-gradient(90deg, var(--ic-accent), #6a7cff);
    border-radius: 50rem;
}

.tiny {
    font-size: 0.75rem;
}

.empty-state {
    border: 1px dashed var(--ic-border);
    background: var(--ic-surface);
}

.empty-illustration {
    width: 120px;
    height: 100px;
    background: radial-gradient(circle at 30% 30%, var(--ic-accent-soft), transparent 55%),
        linear-gradient(145deg, var(--ic-surface-soft), var(--ic-surface));
    border-radius: 1.25rem;
    border: 1px solid var(--ic-border);
    opacity: 0.9;
}

.file-card {
    background: var(--ic-surface);
    border: 1px solid var(--ic-border);
    border-radius: var(--ic-radius);
    box-shadow: var(--ic-shadow-sm);
    overflow: hidden;
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.file-card:hover {
    box-shadow: var(--ic-shadow);
    transform: translateY(-2px);
}

.file-card .preview-wrap {
    aspect-ratio: 4 / 3;
    background: var(--ic-surface-soft);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    position: relative;
}

.file-card .preview-wrap img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.file-card .preview-label {
    position: absolute;
    bottom: 0.5rem;
    left: 0.5rem;
    font-size: 0.65rem;
    padding: 0.15rem 0.45rem;
    border-radius: 50rem;
    background: rgba(0, 0, 0, 0.55);
    color: #fff;
}

.file-card-body {
    padding: 1rem 1.1rem 1.15rem;
}

.badge-status {
    font-weight: 600;
    font-size: 0.7rem;
    padding: 0.35em 0.65em;
    border-radius: 50rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.status-uploaded {
    background: var(--ic-surface-soft);
    color: var(--ic-muted);
}

.status-ready {
    background: rgba(61, 90, 254, 0.12);
    color: var(--ic-accent);
}

.status-converting {
    background: rgba(255, 193, 7, 0.2);
    color: #b78103;
}

[data-theme="dark"] .status-converting {
    color: #ffd666;
}

.status-done {
    background: rgba(25, 135, 84, 0.15);
    color: #198754;
}

.status-failed {
    background: rgba(220, 53, 69, 0.15);
    color: #dc3545;
}

.btn-accent {
    background: var(--ic-accent);
    border-color: var(--ic-accent);
    color: #fff;
    font-weight: 600;
}

.btn-accent:hover {
    background: var(--ic-accent-hover);
    border-color: var(--ic-accent-hover);
    color: #fff;
}

.btn-accent:disabled {
    opacity: 0.55;
}

.form-control,
.form-select {
    background-color: var(--ic-surface);
    color: var(--ic-text);
    border-color: var(--ic-border);
}

.form-control:focus,
.form-select:focus {
    border-color: var(--ic-accent);
    box-shadow: 0 0 0 0.2rem var(--ic-accent-soft);
}

.site-footer {
    border-top: 1px solid var(--ic-border);
    background: var(--ic-surface);
    margin-top: auto;
}

.spinner-ring {
    width: 1.25rem;
    height: 1.25rem;
    border: 2px solid var(--ic-border);
    border-top-color: var(--ic-accent);
    border-radius: 50%;
    animation: ic-spin 0.7s linear infinite;
}

@keyframes ic-spin {
    to {
        transform: rotate(360deg);
    }
}

.preview-grid-mini {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
}

.preview-mini {
    border-radius: 0.5rem;
    border: 1px solid var(--ic-border);
    background: var(--ic-surface-soft);
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.preview-mini img {
    max-width: 100%;
    max-height: 72px;
    object-fit: contain;
}

.preview-mini small {
    font-size: 0.65rem;
    color: var(--ic-muted);
}

.dual-preview .preview-wrap {
    aspect-ratio: 16 / 10;
}

@media (max-width: 575.98px) {
    .file-card .preview-wrap {
        aspect-ratio: 1;
    }
}