/* ═══════════════════════════════════════════════════════════════
   CellProof — Unicode Vibe Aesthetic
   A SaaS Terminal-inspired spreadsheet validator
   ═══════════════════════════════════════════════════════════════ */

:root {
    --bg-primary: #0a0a0a;
    --bg-secondary: #111111;
    --text-primary: #e0e0e0;
    --text-secondary: #888888;
    --text-muted: #555555;
    --accent: #00ff88;
    --accent-dim: #00aa5a;
    --error: #ff4444;
    --warning: #ffaa00;
    --success: #00ff88;
    --border: #333333;
    --shadow: #000000;
}

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

body {
    font-family: 'JetBrains Mono', monospace;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;

    /* Cell-Grid Background */
    background-image: radial-gradient(circle, var(--text-muted) 1px, transparent 1px);
    background-size: 20px 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

/* ─────────────────────────────────────────────────────────────────
   Header
   ───────────────────────────────────────────────────────────────── */

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    text-align: center;
    padding: 2rem;
    background: var(--bg-primary);
    z-index: 100;
}

.header-nav {
    position: absolute;
    top: 1.5rem;
    right: 2rem;
    display: flex;
    gap: 1.5rem;
}

.nav-link {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.8rem;
    letter-spacing: 0.05em;
    transition: color 0.15s ease;
}

.nav-link:hover {
    color: var(--accent);
}

.nav-link.active {
    color: var(--accent);
}

.logo {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    display: inline-block;
}

.logo-bracket {
    color: var(--accent);
}

.logo-text {
    color: var(--text-primary);
}

.tagline {
    color: var(--text-secondary);
    font-size: 0.875rem;
    letter-spacing: 0.1em;
}

/* ─────────────────────────────────────────────────────────────────
   Main Content
   ───────────────────────────────────────────────────────────────── */

.main {
    width: 100%;
    max-width: 600px;
    margin-top: 140px;
}

.section {
    margin-bottom: 2rem;
}

.hidden {
    display: none !important;
}

/* ─────────────────────────────────────────────────────────────────
   Dropzone
   ───────────────────────────────────────────────────────────────── */

.dropzone {
    position: relative;
    width: 100%;
}

.dropzone-border {
    border: 1px solid var(--text-secondary);
    padding: 2.5rem 2rem;
    transition: border-color 0.2s ease;
}

.dropzone:hover .dropzone-border,
.dropzone.drag-over .dropzone-border {
    border-color: var(--accent);
}

.dropzone-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 0.75rem;
}

.dropzone-icon {
    font-size: 2rem;
}

.dropzone-text {
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
}

.dropzone-formats {
    color: var(--text-muted);
    font-size: 0.8rem;
}

.dropzone-divider {
    color: var(--text-muted);
    font-size: 0.8rem;
    margin: 0.5rem 0;
}

.select-btn {
    font-family: inherit;
    font-size: 0.85rem;
    background: transparent;
    border: none;
    color: var(--accent);
    cursor: pointer;
    padding: 0.5rem 1rem;
    transition: all 0.15s ease;
}

.select-btn:hover {
    background: var(--accent);
    color: var(--bg-primary);
    box-shadow: 4px 4px 0px var(--shadow);
}

/* ─────────────────────────────────────────────────────────────────
   File Selected State
   ───────────────────────────────────────────────────────────────── */

.file-selected {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    padding: 1.5rem;
    margin-top: 1rem;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    padding: 0.75rem;
    background: var(--bg-primary);
    border: 1px solid var(--border);
}

.file-icon {
    font-size: 1.25rem;
}

.file-name {
    flex: 1;
    color: var(--accent);
    font-weight: 500;
}

.remove-btn {
    font-family: inherit;
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0.25rem 0.5rem;
    font-size: 1rem;
    transition: color 0.15s ease;
}

.remove-btn:hover {
    color: var(--error);
}

.options {
    margin-bottom: 1.5rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    cursor: pointer;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.checkbox-label input[type="checkbox"] {
    display: none;
}

.checkbox-custom {
    width: 18px;
    height: 18px;
    border: 2px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.15s ease;
}

.checkbox-label input[type="checkbox"]:checked + .checkbox-custom {
    border-color: var(--accent);
    background: var(--accent);
}

.checkbox-label input[type="checkbox"]:checked + .checkbox-custom::after {
    content: "✓";
    color: var(--bg-primary);
    font-size: 0.75rem;
    font-weight: 700;
}

.process-btn {
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    background: var(--accent);
    color: var(--bg-primary);
    border: none;
    padding: 1rem 2rem;
    cursor: pointer;
    width: 100%;
    transition: all 0.15s ease;
    box-shadow: 4px 4px 0px var(--shadow);
}

.process-btn:hover {
    transform: translate(-2px, -2px);
    box-shadow: 6px 6px 0px var(--shadow);
}

.process-btn:active {
    transform: translate(2px, 2px);
    box-shadow: 2px 2px 0px var(--shadow);
}

/* ─────────────────────────────────────────────────────────────────
   Progress Section
   ───────────────────────────────────────────────────────────────── */

.progress-box {
    font-size: 0.85rem;
    white-space: pre;
    color: var(--text-secondary);
    line-height: 1.6;
}

.status-label,
.task-label {
    color: var(--text-muted);
}

.status-text {
    color: var(--accent);
}

#progress-bar {
    color: var(--accent);
    letter-spacing: -0.05em;
}

#progress-pct {
    color: var(--text-primary);
}

#current-task {
    color: var(--text-secondary);
}

/* ─────────────────────────────────────────────────────────────────
   Results Section
   ───────────────────────────────────────────────────────────────── */

.results-header {
    text-align: center;
    margin-bottom: 1.5rem;
}

.results-title {
    color: var(--accent);
    font-size: 0.875rem;
    letter-spacing: 0.05em;
}

.results-summary {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    padding: 1rem;
    margin-bottom: 1.5rem;
    font-size: 0.85rem;
}

.summary-row {
    display: flex;
    justify-content: space-between;
    padding: 0.25rem 0;
    border-bottom: 1px solid var(--border);
}

.summary-row:last-child {
    border-bottom: none;
}

.summary-label {
    color: var(--text-muted);
}

.summary-value {
    color: var(--text-primary);
}

.summary-value.success {
    color: var(--success);
}

.summary-value.error {
    color: var(--error);
}

.results-errors {
    margin-bottom: 1.5rem;
}

/* ─────────────────────────────────────────────────────────────────
   Error Filters
   ───────────────────────────────────────────────────────────────── */

.error-filters {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.filter-btn {
    font-family: inherit;
    font-size: 0.75rem;
    background: var(--bg-secondary);
    color: var(--text-muted);
    border: 1px solid var(--border);
    padding: 0.4rem 0.75rem;
    cursor: pointer;
    transition: all 0.15s ease;
}

.filter-btn:hover {
    border-color: var(--text-secondary);
    color: var(--text-secondary);
}

.filter-btn.active {
    border-color: var(--accent);
    color: var(--accent);
}

.filter-btn.critical.active {
    border-color: var(--error);
    color: var(--error);
}

.filter-btn.warning.active {
    border-color: var(--warning);
    color: var(--warning);
}

.filter-btn.stylistic.active {
    border-color: #8888ff;
    color: #8888ff;
}

.no-errors-filtered {
    color: var(--text-muted);
    text-align: center;
    padding: 2rem;
    font-size: 0.85rem;
}

/* ─────────────────────────────────────────────────────────────────
   Error Cards
   ───────────────────────────────────────────────────────────────── */

.error-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-left: 3px solid var(--error);
    padding: 1rem;
    margin-bottom: 0.75rem;
    font-size: 0.8rem;
}

.error-card.critical {
    border-left-color: var(--error);
}

.error-card.warning {
    border-left-color: var(--warning);
}

.error-card.stylistic {
    border-left-color: #8888ff;
}

.error-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.error-type {
    background: var(--error);
    color: var(--bg-primary);
    padding: 0.125rem 0.5rem;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
}

.error-type.critical {
    background: var(--error);
}

.error-type.warning {
    background: var(--warning);
}

.error-type.stylistic {
    background: #8888ff;
}

.error-location {
    color: var(--text-secondary);
    font-size: 0.75rem;
    margin-left: 0.5rem;
    padding-left: 0.5rem;
    border-left: 1px solid var(--border);
}

.error-address {
    color: var(--text-primary);
    font-weight: 500;
}

.error-arrow {
    color: var(--text-muted);
}

.error-target {
    color: var(--text-secondary);
}

.error-count {
    color: var(--text-muted);
    font-size: 0.7rem;
    margin-left: auto;
}

.error-diagnosis {
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    font-size: 0.85rem;
    line-height: 1.5;
}

.expand-btn {
    font-family: inherit;
    font-size: 0.7rem;
    background: transparent;
    color: var(--text-muted);
    border: none;
    padding: 0;
    cursor: pointer;
    text-decoration: underline;
    margin-bottom: 0.5rem;
}

.expand-btn:hover {
    color: var(--accent);
}

.cell-details {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    padding: 0.75rem;
    margin-top: 0.5rem;
    font-size: 0.75rem;
    max-height: 150px;
    overflow-y: auto;
}

.cell-detail {
    margin-bottom: 0.5rem;
    word-break: break-all;
}

.cell-detail:last-child {
    margin-bottom: 0;
}

.cell-label {
    color: var(--text-muted);
    margin-right: 0.5rem;
}

.error-description {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    padding-left: 0.5rem;
    border-left: 2px solid var(--border);
}

.error-suggestion {
    color: var(--accent-dim);
    font-size: 0.75rem;
}

.error-suggestion::before {
    content: "→ ";
}

.no-errors {
    text-align: center;
    padding: 2rem;
    background: var(--bg-secondary);
    border: 1px solid var(--accent);
}

.no-errors-icon {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.no-errors-text {
    color: var(--accent);
    font-weight: 500;
}

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

.action-btn {
    font-family: inherit;
    font-size: 0.875rem;
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
    padding: 0.75rem 1.5rem;
    cursor: pointer;
    transition: all 0.15s ease;
}

.action-btn:hover {
    color: var(--accent);
    border-color: var(--accent);
    box-shadow: 4px 4px 0px var(--shadow);
}

/* ─────────────────────────────────────────────────────────────────
   Page Content (Changelog, Feedback)
   ───────────────────────────────────────────────────────────────── */

.page-title {
    color: var(--accent);
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    margin-bottom: 1.5rem;
    text-align: center;
}

.page-content {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    padding: 2rem;
    min-height: 200px;
    color: var(--text-secondary);
}

/* ─────────────────────────────────────────────────────────────────
   Changelog
   ───────────────────────────────────────────────────────────────── */

.changelog {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.changelog-entry {
    display: flex;
    gap: 2rem;
    padding: 1.5rem 0;
    border-bottom: 1px solid var(--border);
}

.changelog-entry:last-child {
    border-bottom: none;
}

.changelog-date {
    flex-shrink: 0;
    width: 80px;
    color: var(--accent);
    font-size: 0.85rem;
    font-weight: 500;
}

.changelog-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.changelog-item {
    color: var(--text-primary);
    font-size: 0.9rem;
    line-height: 1.4;
}

.changelog-item::before {
    content: "→ ";
    color: var(--accent);
}

/* ─────────────────────────────────────────────────────────────────
   Feedback / Voting
   ───────────────────────────────────────────────────────────────── */

.section-title {
    color: var(--text-primary);
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    text-align: center;
}

.section-subtitle {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-bottom: 2rem;
    text-align: center;
}

.feedback-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.feedback-item {
    display: flex;
    gap: 1rem;
    padding: 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    transition: border-color 0.15s ease;
}

.feedback-item:hover {
    border-color: var(--text-muted);
}

.loading {
    text-align: center;
    padding: 2rem;
    color: var(--text-muted);
}

.feedback-vote {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
    min-width: 40px;
}

.vote-btn {
    font-family: inherit;
    font-size: 1rem;
    background: transparent;
    color: var(--text-muted);
    border: 1px solid var(--border);
    width: 32px;
    height: 32px;
    cursor: pointer;
    transition: all 0.15s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.vote-btn:hover {
    color: var(--accent);
    border-color: var(--accent);
    background: rgba(0, 255, 136, 0.1);
}

.vote-count {
    color: var(--accent);
    font-size: 0.9rem;
    font-weight: 600;
}

.feedback-content {
    flex: 1;
}

.feedback-title {
    color: var(--text-primary);
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 0.25rem;
}

.feedback-desc {
    color: var(--text-secondary);
    font-size: 0.8rem;
    line-height: 1.4;
}

.user-badge {
    font-size: 0.65rem;
    background: var(--accent-dim);
    color: var(--bg-primary);
    padding: 0.1rem 0.4rem;
    border-radius: 2px;
    margin-left: 0.5rem;
    font-weight: 600;
    text-transform: uppercase;
}

.load-more-container {
    display: flex;
    justify-content: center;
    margin: 1.5rem 0;
}

.load-more-btn {
    font-family: inherit;
    font-size: 0.85rem;
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
    padding: 0.5rem 1.5rem;
    cursor: pointer;
    transition: all 0.15s ease;
}

.load-more-btn:hover {
    color: var(--accent);
    border-color: var(--accent);
}

/* ─────────────────────────────────────────────────────────────────
   Suggestion Form
   ───────────────────────────────────────────────────────────────── */

.suggestion-form {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
}

.suggestion-title {
    color: var(--text-primary);
    font-size: 0.95rem;
    font-weight: 500;
    margin-bottom: 0.75rem;
}

.suggestion-input {
    width: 100%;
    min-height: 100px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.85rem;
    padding: 0.75rem;
    resize: vertical;
    transition: border-color 0.15s ease;
}

.suggestion-input:focus {
    outline: none;
    border-color: var(--accent);
}

.suggestion-input::placeholder {
    color: var(--text-muted);
}

.suggestion-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 0.5rem;
}

.char-count {
    color: var(--text-muted);
    font-size: 0.75rem;
}

.submit-btn {
    font-family: inherit;
    font-size: 0.85rem;
    background: var(--accent);
    color: var(--bg-primary);
    border: none;
    padding: 0.5rem 1.25rem;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.15s ease;
}

.submit-btn:hover {
    background: var(--accent-dim);
}

/* ─────────────────────────────────────────────────────────────────
   Email Modal
   ───────────────────────────────────────────────────────────────── */

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    padding: 2rem;
    max-width: 400px;
    width: 90%;
}

.modal-header {
    color: var(--text-primary);
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.modal-text {
    color: var(--text-secondary);
    font-size: 0.85rem;
    margin-bottom: 1rem;
}

.email-input {
    width: 100%;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.85rem;
    padding: 0.75rem;
    margin-bottom: 1rem;
}

.email-input:focus {
    outline: none;
    border-color: var(--accent);
}

.email-input::placeholder {
    color: var(--text-muted);
}

.modal-buttons {
    display: flex;
    gap: 0.75rem;
    justify-content: flex-end;
}

.modal-btn {
    font-family: inherit;
    font-size: 0.85rem;
    padding: 0.5rem 1rem;
    cursor: pointer;
    border: 1px solid var(--border);
    transition: all 0.15s ease;
}

.modal-btn.secondary {
    background: transparent;
    color: var(--text-secondary);
}

.modal-btn.secondary:hover {
    color: var(--text-primary);
    border-color: var(--text-muted);
}

.modal-btn.primary {
    background: var(--accent);
    color: var(--bg-primary);
    border-color: var(--accent);
    font-weight: 600;
}

.modal-btn.primary:hover {
    background: var(--accent-dim);
    border-color: var(--accent-dim);
}

/* ─────────────────────────────────────────────────────────────────
   Celebration Overlay
   ───────────────────────────────────────────────────────────────── */

.celebration-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.85);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
}

.celebration-content {
    text-align: center;
    z-index: 2001;
}

.celebration-emoji {
    font-size: 4rem;
    margin-bottom: 1rem;
    animation: bounce 0.5s ease infinite alternate;
}

@keyframes bounce {
    from { transform: translateY(0); }
    to { transform: translateY(-10px); }
}

.celebration-title {
    color: var(--accent);
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.celebration-text {
    color: var(--text-primary);
    font-size: 1rem;
}

#confetti-canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

/* ─────────────────────────────────────────────────────────────────
   Responsive
   ───────────────────────────────────────────────────────────────── */

@media (max-width: 640px) {
    .container {
        padding: 1rem;
    }

    .progress-box {
        font-size: 0.65rem;
        overflow-x: auto;
    }

    .logo {
        font-size: 1.5rem;
    }

    .header {
        padding: 1rem;
    }

    .header-nav {
        position: static;
        justify-content: center;
        margin-bottom: 1rem;
    }
}