:root {
    --bg-dark: #111827;
    --bg-panel: #1F2937;
    --bg-input: #374151;

    --text-main: #F9FAFB;
    --text-muted: #9CA3AF;
    --border: #374151;
    --border-light: #4B5563;

    --color-breaking: #EF4444;
    /* Red */
    --color-added: #22C55E;
    /* Green */
    --color-modified: #F59E0B;
    /* Amber */
    --color-unchanged: #6B7280;
    /* Gray */

    --bg-breaking: rgba(239, 68, 68, 0.1);
    --bg-added: rgba(34, 197, 94, 0.1);
    --bg-modified: rgba(245, 158, 11, 0.1);

    --font-sans: 'Inter', system-ui, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;

    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
}

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

body {
    font-family: var(--font-sans);
    background-color: var(--bg-dark);
    color: var(--text-main);
    min-height: 100vh;
}

.app-layout {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Navbar */
.navbar {
    height: 60px;
    padding: 0 1.5rem;
    background: var(--bg-panel);
    border-bottom: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 100;
}

.brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 600;
    font-size: 1.1rem;
}

.nav-controls {
    display: flex;
    gap: 1rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    font-weight: 500;
    font-size: 0.875rem;
    border-radius: var(--radius-sm);
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: var(--font-sans);
}

.btn.primary {
    background: var(--text-main);
    color: var(--bg-dark);
}

.btn.primary:hover {
    background: #E5E7EB;
}

.btn.outline {
    background: transparent;
    color: var(--text-main);
    border: 1px solid var(--border-light);
}

.btn.outline:hover {
    background: var(--bg-input);
}

.btn.sm {
    padding: 0.35rem 0.75rem;
    font-size: 0.8rem;
}

.btn.lg {
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
}

.main-content {
    flex-grow: 1;
    padding: 2rem;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

.view-state {
    display: none;
    animation: fadeIn 0.3s ease;
}

.view-state.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(5px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Upload View */
.hero {
    text-align: center;
    margin-bottom: 2rem;
}

.hero h1 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    font-weight: 700;
}

.hero p {
    color: var(--text-muted);
    font-size: 1rem;
}

.upload-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.upload-card {
    background: var(--bg-panel);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.card-header {
    padding: 1rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(0, 0, 0, 0.2);
}

.badge {
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-weight: 600;
    font-size: 0.75rem;
    letter-spacing: 0.05em;
    background: var(--border-light);
    color: var(--text-main);
}

.card-body {
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    flex-grow: 1;
}

.drop-zone {
    border: 2px dashed var(--border-light);
    border-radius: var(--radius-sm);
    padding: 1.5rem 1rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
    background: rgba(0, 0, 0, 0.1);
}

.drop-zone:hover,
.drop-zone.dragover {
    border-color: var(--text-main);
    background: var(--bg-input);
}

.drop-zone p {
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 0.2rem;
}

.drop-zone span {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.raw-input {
    width: 100%;
    height: 250px;
    background: var(--bg-dark);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-main);
    padding: 1rem;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    line-height: 1.5;
    resize: none;
    transition: border 0.2s;
}

.raw-input:focus {
    outline: none;
    border-color: var(--text-muted);
}

.actions-wrapper {
    text-align: center;
}

/* Results View */
.results-toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.filters {
    display: flex;
    gap: 1rem;
    background: var(--bg-panel);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
}

.filter-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
}

.filter-label input {
    cursor: pointer;
}

.summary-banner {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin-bottom: 2rem;
}

.summary-item {
    padding: 1rem;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    border: 1px solid var(--border);
    background: var(--bg-panel);
}

.summary-item .val {
    font-size: 2rem;
    font-weight: 700;
    font-family: var(--font-mono);
}

.summary-item .label {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
}

.summary-item.breaking .val {
    color: var(--color-breaking);
}

.summary-item.added .val {
    color: var(--color-added);
}

.summary-item.modified .val {
    color: var(--color-modified);
}

/* Diff Tree Elements */
.diff-viewer {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.ep-diff {
    background: var(--bg-panel);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    font-family: var(--font-mono);
    font-size: 0.875rem;
    overflow: hidden;
}

.ep-header {
    padding: 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    border-bottom: 1px solid var(--border);
    background: rgba(0, 0, 0, 0.2);
}

.ep-method {
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-weight: 600;
    font-size: 0.75rem;
    background: var(--bg-input);
}

.ep-path {
    font-weight: 500;
    color: var(--text-main);
}

.ep-badge {
    margin-left: auto;
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-size: 0.7rem;
    font-weight: 600;
}

.ep-badge.breaking {
    background: var(--bg-breaking);
    color: var(--color-breaking);
    border: 1px solid var(--color-breaking);
}

.ep-badge.added {
    background: var(--bg-added);
    color: var(--color-added);
    border: 1px solid var(--color-added);
}

.ep-badge.modified {
    background: var(--bg-modified);
    color: var(--color-modified);
    border: 1px solid var(--color-modified);
}

.diff-body {
    padding: 1rem;
    background: var(--bg-dark);
}

.diff-tree {
    display: flex;
    flex-direction: column;
}

.diff-line {
    display: flex;
    padding: 0.25rem 0.5rem;
    align-items: flex-start;
    gap: 1rem;
    border-radius: 4px;
}

.diff-line:hover {
    background: rgba(255, 255, 255, 0.02);
}

.diff-line.t-add {
    background: var(--bg-added);
    color: var(--color-added);
}

.diff-line.t-rem {
    background: var(--bg-breaking);
    color: var(--color-breaking);
    text-decoration: line-through;
}

.diff-line.t-mod {
    background: var(--bg-modified);
    color: var(--color-modified);
}

.l-indent {
    display: inline-block;
    width: 1.5rem;
    text-align: center;
    opacity: 0.5;
}

.l-key {
    font-weight: 600;
}

.l-val {
    word-break: break-all;
    opacity: 0.9;
}

.l-arrow {
    opacity: 0.5;
    margin: 0 0.5rem;
}

.strikethrough {
    text-decoration: line-through;
    opacity: 0.7;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-dark);
}

::-webkit-scrollbar-thumb {
    background: var(--border-light);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}