@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&display=swap');

:root {
    --bg-color: #000000;
    --container-bg: #0a0a0a;
    --card-bg: #111111;
    --text-color: #ededed;
    --text-muted: #a1a1aa;
    --border-color: #27272a;
    --border-hover: #3f3f46;
    --primary-color: #ededed;
    --primary-invert: #000000;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --success-color: #10b981;
    --success-bg: rgba(16, 185, 129, 0.1);
    --error-color: #ef4444;
    --error-bg: rgba(239, 68, 68, 0.1);
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

[data-theme="light"] {
    --bg-color: #f9fafb;
    --container-bg: #ffffff;
    --card-bg: #f3f4f6;
    --text-color: #111827;
    --text-muted: #6b7280;
    --border-color: #e5e7eb;
    --border-hover: #d1d5db;
    --primary-color: #111827;
    --primary-invert: #ffffff;
    --accent-color: #2563eb;
    --accent-hover: #1d4ed8;
    --success-bg: rgba(16, 185, 129, 0.15);
    --error-bg: rgba(239, 68, 68, 0.15);
}

.theme-toggle {
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    border-radius: 6px;
    padding: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle:hover {
    color: var(--text-color);
    background: var(--card-bg);
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.5;
    min-height: 100vh;
    padding: 3rem 1rem;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2.5rem;
    background-color: var(--container-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
}

header {
    margin-bottom: 3rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 2rem;
}

header h1 {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.025em;
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

header p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

.tabs {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.tab-btn {
    padding: 0.5rem 1rem;
    background: transparent;
    border: 1px solid transparent;
    border-radius: 6px;
    font-size: 0.9rem;
    font-family: inherit;
    font-weight: 500;
    cursor: pointer;
    color: var(--text-muted);
    transition: all 0.2s ease;
}

.tab-btn:hover {
    color: var(--text-color);
    background: var(--card-bg);
}

.tab-btn.active {
    background: var(--card-bg);
    color: var(--text-color);
    border-color: var(--border-color);
}

.tab-content {
    display: none;
    animation: fadeIn 0.2s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.tab-content.active {
    display: block;
}

.form-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    font-size: 0.875rem;
    color: var(--text-color);
}

.required {
    color: var(--error-color);
}

.input-toggle {
    display: flex;
    gap: 1.5rem;
    margin-bottom: 1rem;
}

.input-toggle label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-muted);
    cursor: pointer;
    font-weight: 400;
}

.input-toggle label:hover {
    color: var(--text-color);
}

textarea, input[type="number"], select {
    width: 100%;
    padding: 0.75rem;
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-family: 'Inter', monospace;
    font-size: 0.9rem;
    color: var(--text-color);
    transition: border-color 0.15s, box-shadow 0.15s;
}

textarea:focus, input[type="number"]:focus, select:focus {
    outline: none;
    border-color: var(--text-muted);
}

.drop-zone {
    border: 1px dashed var(--border-color);
    border-radius: 8px;
    padding: 2.5rem 1.5rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
    background-color: var(--card-bg);
    position: relative;
}

.drop-zone:hover, .drop-zone.drag-over {
    border-color: var(--text-muted);
    background-color: #18181b;
}

.drop-zone span {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.drop-zone input[type="file"] {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
}

.file-name {
    margin-top: 0.5rem;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.options-section {
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
}

.options-section h3 {
    margin-bottom: 1.25rem;
    font-size: 0.95rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
}

.options-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.25rem;
}

input[type="checkbox"] {
    appearance: none;
    -webkit-appearance: none;
    width: 1.125rem;
    height: 1.125rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: var(--bg-color);
    cursor: pointer;
    position: relative;
    transition: all 0.15s;
}

input[type="checkbox"]:checked {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

input[type="checkbox"]:checked::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 5px;
    width: 4px;
    height: 8px;
    border: solid var(--primary-invert);
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

.checkbox-group {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.checkbox-group label {
    margin: 0;
    cursor: pointer;
    color: var(--text-muted);
    font-weight: 400;
}

.checkbox-group:hover label {
    color: var(--text-color);
}

.actions {
    margin-top: 3rem;
    display: flex;
    justify-content: flex-end;
}

.primary-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    background-color: var(--primary-color);
    color: var(--primary-invert);
    border: 1px solid transparent;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    text-decoration: none;
    transition: opacity 0.2s, transform 0.1s;
}

.primary-btn:hover {
    opacity: 0.9;
}

.primary-btn:active {
    transform: scale(0.98);
}

.primary-btn:disabled, .primary-btn.btn-disabled {
    background-color: var(--border-color) !important;
    color: var(--text-muted) !important;
    cursor: not-allowed;
    pointer-events: none;
}

.btn-secondary {
    background-color: var(--card-bg);
    color: var(--text-color);
    border-color: var(--border-color);
}
.btn-secondary:hover {
    border-color: var(--text-muted);
    opacity: 1;
}

#progress {
    margin-top: 2rem;
    padding: 1.25rem;
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
}

#progress-text {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 0.75rem;
}

#progress-bar-outer {
    width: 100%;
    height: 4px;
    background-color: var(--border-color);
    border-radius: 2px;
    overflow: hidden;
}

#progress-bar-inner {
    height: 100%;
    width: 30%;
    background-color: var(--text-muted);
    border-radius: 2px;
    animation: progress-slide 1.5s ease-in-out infinite;
}

@keyframes progress-slide {
    0%   { margin-left: -30%; width: 30%; }
    50%  { width: 50%; }
    100% { margin-left: 100%; width: 30%; }
}

.hidden {
    display: none !important;
}

#results {
    margin-top: 3rem;
    padding: 2rem;
    background-color: var(--card-bg);
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

#results.success {
    border-color: var(--success-color);
}

#results-title {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    font-weight: 500;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 1rem;
    margin: 1.5rem 0;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

.stat .label {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.25rem;
}

.stat span:not(.label) {
    font-size: 1.1rem;
    font-weight: 500;
}

#preview-container {
    margin: 2rem 0;
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1.5rem;
    overflow: auto;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 200px;
}

.notice {
    margin: 1.5rem 0;
    padding: 1rem;
    background-color: rgba(234, 179, 8, 0.1);
    border-left: 3px solid #eab308;
    font-size: 0.85rem;
    color: #fde047;
}

.error {
    margin-top: 2rem;
    padding: 1rem;
    background-color: var(--error-bg);
    border: 1px solid rgba(239, 68, 68, 0.2);
    border-radius: 6px;
    color: #f87171;
    font-size: 0.9rem;
}

footer {
    margin-top: 3rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.75rem;
}

.download-buttons {
    display: flex;
    gap: 0.75rem;
    justify-content: flex-end;
    flex-wrap: wrap;
    margin-top: 1.5rem;
}

@media (max-width: 640px) {
    .container {
        padding: 1.5rem;
        border: none;
        border-radius: 0;
    }
    .options-grid {
        grid-template-columns: 1fr;
    }
    .actions {
        justify-content: stretch;
    }
    .primary-btn {
        width: 100%;
    }
    .download-buttons {
        flex-direction: column;
    }
}