/* ==========================================================================
   StudyNotes Modern Application Stylesheet
   ========================================================================== */

:root {
    --bg-base: #f8fafc;
    --bg-surface: #ffffff;
    --bg-card: #ffffff;
    --bg-subtle: #f1f5f9;
    --border-main: #e2e8f0;
    --border-light: #f1f5f9;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --text-dim: #94a3b8;
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --primary-soft: rgba(37, 99, 235, 0.08);
    --badge-bg: #eff6ff;
    --badge-text: #1d4ed8;
    --danger: #ef4444;
    --danger-hover: #dc2626;
    --danger-soft: rgba(239, 68, 68, 0.08);
    --success: #10b981;
    --code-bg: #1e293b;
    --code-text: #f8fafc;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-full: 9999px;
    --font-sans: 'Plus Jakarta Sans', system-ui, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
}

html.dark {
    --bg-base: #090d16;
    --bg-surface: #101623;
    --bg-card: #141c2e;
    --bg-subtle: #172133;
    --border-main: #1e293b;
    --border-light: #161f30;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --text-dim: #64748b;
    --primary: #38bdf8;
    --primary-hover: #0ea5e9;
    --primary-soft: rgba(56, 189, 248, 0.12);
    --badge-bg: rgba(56, 189, 248, 0.15);
    --badge-text: #7dd3fc;
    --danger: #f87171;
    --danger-hover: #ef4444;
    --danger-soft: rgba(248, 113, 113, 0.15);
    --code-bg: #0b0f19;
    --code-text: #e2e8f0;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

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

body {
    font-family: var(--font-sans);
    background-color: var(--bg-base);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background-color 0.25s ease, color 0.25s ease;
}

/* ==========================================================================
   Navbar
   ========================================================================== */
.navbar {
    position: sticky;
    top: 0;
    background-color: rgba(255, 255, 255, 0.88);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-main);
    z-index: 100;
    transition: background-color 0.25s ease, border-color 0.25s ease;
}

html.dark .navbar {
    background-color: rgba(16, 22, 35, 0.88);
}

.nav-container {
    max-width: 1240px;
    margin: 0 auto;
    padding: 0.85rem 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    cursor: pointer;
    user-select: none;
}

.brand-icon {
    font-size: 1.7rem;
    line-height: 1;
}

.brand-name {
    font-size: 1.15rem;
    font-weight: 800;
    line-height: 1.2;
    display: block;
    color: var(--text-main);
}

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

.nav-search {
    flex: 1;
    max-width: 440px;
    position: relative;
    display: flex;
    align-items: center;
}

.nav-search svg {
    position: absolute;
    left: 0.85rem;
    color: var(--text-dim);
    pointer-events: none;
}

.nav-search input {
    width: 100%;
    padding: 0.55rem 1rem 0.55rem 2.4rem;
    background-color: var(--bg-surface);
    border: 1px solid var(--border-main);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-family: inherit;
    color: var(--text-main);
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.nav-search input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-soft);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.btn-theme-toggle {
    width: 38px;
    height: 38px;
    border-radius: var(--radius-sm);
    background: var(--bg-surface);
    border: 1px solid var(--border-main);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    transition: all 0.2s;
}

.btn-theme-toggle:hover {
    border-color: var(--primary);
    background-color: var(--primary-soft);
}

.sun-icon { display: block; }
.moon-icon { display: none; }
html.dark .sun-icon { display: none; }
html.dark .moon-icon { display: block; }

.btn-primary {
    background-color: var(--primary);
    color: #ffffff;
    border: none;
    padding: 0.55rem 1.15rem;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    font-family: inherit;
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    transition: all 0.2s;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

/* ==========================================================================
   Main App & Views
   ========================================================================== */
.app-main {
    flex: 1;
    max-width: 1240px;
    margin: 0 auto;
    width: 100%;
    padding: 2rem 1.5rem 4rem;
}

.view-section {
    display: none;
}

.view-section.active {
    display: block;
    animation: fadeIn 0.25s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(6px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ==========================================================================
   Hero Block
   ========================================================================== */
.hero-block {
    text-align: center;
    padding: 2.5rem 1.5rem 1.75rem;
    max-width: 780px;
    margin: 0 auto;
}

.hero-badge {
    display: inline-block;
    padding: 0.35rem 0.9rem;
    background-color: var(--badge-bg);
    color: var(--badge-text);
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: var(--radius-full);
    margin-bottom: 0.85rem;
}

.hero-title {
    font-size: 2.25rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 0.75rem;
    line-height: 1.25;
}

.hero-desc {
    color: var(--text-muted);
    font-size: 1.05rem;
    line-height: 1.6;
}

/* Categories Bar */
.filter-wrapper {
    margin: 1.5rem 0 2.5rem;
}

.categories-bar {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.5rem;
}

.cat-chip {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.45rem 1rem;
    background-color: var(--bg-surface);
    border: 1px solid var(--border-main);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-muted);
    cursor: pointer;
    font-family: inherit;
    transition: all 0.2s;
}

.cat-chip:hover, .cat-chip.active {
    color: var(--primary);
    border-color: var(--primary);
    background-color: var(--primary-soft);
}

.chip-count {
    font-size: 0.75rem;
    background-color: var(--bg-subtle);
    color: var(--text-dim);
    padding: 0.1rem 0.5rem;
    border-radius: var(--radius-full);
}

.cat-chip.active .chip-count {
    background-color: var(--primary);
    color: #ffffff;
}

/* ==========================================================================
   Notes Grid Layout
   ========================================================================== */
.notes-header-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1.5rem;
}

.notes-list-title {
    font-size: 1.25rem;
    font-weight: 700;
}

.total-notes-badge {
    font-size: 0.8rem;
    background-color: var(--bg-subtle);
    color: var(--text-muted);
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-full);
    font-weight: 600;
}

.notes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 1.5rem;
}

.note-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-main);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    cursor: pointer;
    transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
    position: relative;
}

.note-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.card-top-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    margin-bottom: 0.85rem;
}

.card-cat-badge {
    background-color: var(--badge-bg);
    color: var(--badge-text);
    font-size: 0.75rem;
    font-weight: 700;
    padding: 0.2rem 0.65rem;
    border-radius: var(--radius-sm);
}

.card-date {
    font-size: 0.775rem;
    color: var(--text-dim);
}

.card-title {
    font-size: 1.15rem;
    font-weight: 700;
    line-height: 1.4;
    margin-bottom: 0.75rem;
    color: var(--text-main);
}

.card-excerpt {
    font-size: 0.9rem;
    color: var(--text-muted);
    line-height: 1.6;
    margin-bottom: 1.25rem;
    flex-grow: 1;
}

.card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem;
    margin-bottom: 1rem;
}

.tag-item {
    font-size: 0.75rem;
    background-color: var(--bg-subtle);
    color: var(--text-muted);
    padding: 0.15rem 0.5rem;
    border-radius: var(--radius-sm);
}

.card-bottom-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 1rem;
    border-top: 1px solid var(--border-light);
    margin-top: auto;
}

.card-reading-time {
    font-size: 0.8rem;
    color: var(--text-dim);
}

.card-actions-quick {
    display: flex;
    gap: 0.4rem;
}

.btn-icon-action {
    background: none;
    border: none;
    padding: 0.3rem 0.45rem;
    border-radius: var(--radius-sm);
    color: var(--text-dim);
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.2s;
}

.btn-icon-action:hover {
    color: var(--text-main);
    background-color: var(--bg-subtle);
}

.btn-icon-action.delete:hover {
    color: var(--danger);
    background-color: var(--danger-soft);
}

/* ==========================================================================
   Reader View & Sticky Table of Contents (TOC)
   ========================================================================== */
.reader-container {
    max-width: 1160px;
    margin: 0 auto;
}

.reader-top-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-main);
}

.btn-back {
    background: none;
    border: 1px solid var(--border-main);
    padding: 0.45rem 0.95rem;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-muted);
    cursor: pointer;
    font-family: inherit;
    transition: all 0.2s;
}

.btn-back:hover {
    color: var(--primary);
    border-color: var(--primary);
    background-color: var(--primary-soft);
}

.reader-actions {
    display: flex;
    gap: 0.6rem;
}

.btn-outline {
    background: var(--bg-surface);
    border: 1px solid var(--border-main);
    padding: 0.45rem 0.95rem;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-main);
    cursor: pointer;
    font-family: inherit;
    transition: all 0.2s;
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.btn-danger-outline {
    background: var(--bg-surface);
    border: 1px solid var(--border-main);
    padding: 0.45rem 0.95rem;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--danger);
    cursor: pointer;
    font-family: inherit;
    transition: all 0.2s;
}

.btn-danger-outline:hover {
    background-color: var(--danger-soft);
    border-color: var(--danger);
}

.reader-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 280px;
    gap: 3.5rem;
    align-items: start;
}

.reader-header {
    margin-bottom: 2.5rem;
}

.reader-meta-pills {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 0.85rem;
    color: var(--text-dim);
    margin-bottom: 0.85rem;
}

.badge-cat {
    background-color: var(--badge-bg);
    color: var(--badge-text);
    font-weight: 700;
    padding: 0.2rem 0.65rem;
    border-radius: var(--radius-sm);
}

.reader-title {
    font-size: 2.25rem;
    font-weight: 800;
    line-height: 1.3;
    letter-spacing: -0.02em;
    margin-bottom: 1rem;
}

.reader-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
}

/* Markdown Body Styling */
.markdown-body {
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--text-main);
}

.markdown-body h1, .markdown-body h2, .markdown-body h3 {
    font-weight: 700;
    margin-top: 2rem;
    margin-bottom: 0.85rem;
    line-height: 1.35;
    scroll-margin-top: 85px;
}

.markdown-body h2 {
    font-size: 1.55rem;
    border-bottom: 1px solid var(--border-main);
    padding-bottom: 0.45rem;
}

.markdown-body h3 {
    font-size: 1.25rem;
}

.markdown-body p {
    margin-bottom: 1.25rem;
    color: var(--text-muted);
}

.markdown-body ul, .markdown-body ol {
    margin-bottom: 1.25rem;
    padding-left: 1.5rem;
    color: var(--text-muted);
}

.markdown-body li {
    margin-bottom: 0.4rem;
}

.markdown-body blockquote {
    margin: 1.5rem 0;
    padding: 1rem 1.25rem;
    background-color: var(--primary-soft);
    border-left: 4px solid var(--primary);
    border-radius: 0 var(--radius-md) var(--radius-md) 0;
    color: var(--text-main);
}

.markdown-body pre {
    background-color: var(--code-bg);
    color: var(--code-text);
    padding: 1.25rem;
    border-radius: var(--radius-md);
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: 0.875rem;
    line-height: 1.6;
    margin: 1.75rem 0;
}

.markdown-body code {
    font-family: var(--font-mono);
    font-size: 0.875em;
    background-color: var(--primary-soft);
    color: var(--primary);
    padding: 0.15rem 0.35rem;
    border-radius: 4px;
}

.markdown-body pre code {
    background: transparent;
    color: inherit;
    padding: 0;
}

.markdown-body table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.75rem 0;
    font-size: 0.95rem;
}

.markdown-body th, .markdown-body td {
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-main);
    text-align: left;
}

.markdown-body th {
    background-color: var(--bg-subtle);
    font-weight: 600;
}

/* Sticky Table of Contents (TOC) */
.reader-sidebar {
    position: sticky;
    top: 85px;
}

.sticky-toc-box {
    background-color: var(--bg-surface);
    border: 1px solid var(--border-main);
    border-radius: var(--radius-lg);
    padding: 1.25rem;
    box-shadow: var(--shadow-sm);
    max-height: calc(100vh - 120px);
    overflow-y: auto;
}

.toc-title-bar {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.85rem;
    padding-bottom: 0.65rem;
    border-bottom: 1px solid var(--border-light);
}

.toc-title-bar h3 {
    font-size: 0.9rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.toc-nav ul {
    list-style: none;
}

.toc-nav li {
    margin-bottom: 0.35rem;
}

.toc-nav li.toc-h3 {
    padding-left: 1rem;
    font-size: 0.825rem;
}

.toc-nav a {
    display: block;
    font-size: 0.85rem;
    color: var(--text-muted);
    text-decoration: none;
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    border-left: 2px solid transparent;
    transition: all 0.2s;
    line-height: 1.45;
}

.toc-nav a:hover {
    color: var(--primary);
    background-color: var(--primary-soft);
}

.toc-nav a.active {
    color: var(--primary);
    font-weight: 600;
    border-left-color: var(--primary);
    background-color: var(--primary-soft);
}

.toc-empty {
    font-size: 0.825rem;
    color: var(--text-dim);
}

.toc-footer {
    margin-top: 1.25rem;
    padding-top: 0.85rem;
    border-top: 1px solid var(--border-light);
}

.btn-copy-link {
    width: 100%;
    background: none;
    border: 1px dashed var(--border-main);
    color: var(--text-muted);
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    font-weight: 600;
    cursor: pointer;
    font-family: inherit;
    transition: all 0.2s;
}

.btn-copy-link:hover {
    border-color: var(--primary);
    color: var(--primary);
}

/* ==========================================================================
   Editor Modal
   ========================================================================== */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 1rem;
}

.modal-overlay.is-open {
    display: flex;
}

.modal-dialog {
    background-color: var(--bg-surface);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-main);
    width: 100%;
    max-width: 820px;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-lg);
    animation: modalPop 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes modalPop {
    from { opacity: 0; transform: scale(0.96); }
    to { opacity: 1; transform: scale(1); }
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--border-main);
}

.modal-title {
    font-size: 1.25rem;
    font-weight: 700;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    line-height: 1;
    color: var(--text-dim);
    cursor: pointer;
}

.modal-close:hover {
    color: var(--text-main);
}

.editor-form {
    display: flex;
    flex-direction: column;
    overflow-y: auto;
    padding: 1.5rem;
    gap: 1.25rem;
}

.form-row {
    display: flex;
    gap: 1rem;
}

.flex-1 { flex: 1; }
.flex-2 { flex: 2; }

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.form-group label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-main);
}

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

.form-group input, .form-group textarea {
    padding: 0.65rem 0.85rem;
    background-color: var(--bg-base);
    border: 1px solid var(--border-main);
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 0.925rem;
    color: var(--text-main);
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-group input:focus, .form-group textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-soft);
}

/* Editor Toolbar */
.editor-toolbar {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.35rem;
    padding: 0.4rem;
    background-color: var(--bg-base);
    border: 1px solid var(--border-main);
    border-bottom: none;
    border-radius: var(--radius-sm) var(--radius-sm) 0 0;
}

.tool-btn {
    background: var(--bg-surface);
    border: 1px solid var(--border-main);
    color: var(--text-muted);
    padding: 0.25rem 0.6rem;
    border-radius: 4px;
    font-size: 0.775rem;
    font-weight: 600;
    cursor: pointer;
    font-family: inherit;
    transition: all 0.15s;
}

.tool-btn:hover {
    color: var(--primary);
    border-color: var(--primary);
    background-color: var(--primary-soft);
}

.tool-sep {
    width: 1px;
    height: 16px;
    background-color: var(--border-main);
    margin: 0 0.25rem;
}

.editor-body-group {
    position: relative;
}

.editor-body-group textarea {
    min-height: 280px;
    border-radius: 0 0 var(--radius-sm) var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.9rem;
    line-height: 1.6;
    resize: vertical;
}

.editor-preview-box {
    display: none;
    min-height: 280px;
    max-height: 380px;
    overflow-y: auto;
    padding: 1rem;
    background-color: var(--bg-surface);
    border: 1px solid var(--border-main);
    border-radius: 0 0 var(--radius-sm) var(--radius-sm);
}

.editor-preview-box.is-visible {
    display: block;
}

.modal-footer {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 0.75rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-light);
}

.btn-cancel {
    background: none;
    border: 1px solid var(--border-main);
    padding: 0.55rem 1.15rem;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-muted);
    cursor: pointer;
    font-family: inherit;
}

.btn-cancel:hover {
    background-color: var(--bg-subtle);
}

/* ==========================================================================
   Confirm Delete Modal & Toast
   ========================================================================== */
.confirm-box {
    background-color: var(--bg-surface);
    border-radius: var(--radius-lg);
    padding: 2rem;
    max-width: 440px;
    width: 100%;
    text-align: center;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-main);
}

.confirm-icon {
    font-size: 2.5rem;
    margin-bottom: 0.75rem;
}

.confirm-box h3 {
    margin-bottom: 0.5rem;
}

.confirm-box p {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
}

.confirm-actions {
    display: flex;
    justify-content: center;
    gap: 0.75rem;
}

.btn-danger {
    background-color: var(--danger);
    color: #ffffff;
    border: none;
    padding: 0.55rem 1.15rem;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
}

.btn-danger:hover {
    background-color: var(--danger-hover);
}

/* Toast */
.toast {
    position: fixed;
    bottom: 24px;
    right: 24px;
    background-color: var(--bg-surface);
    border: 1px solid var(--border-main);
    color: var(--text-main);
    padding: 0.75rem 1.25rem;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    font-size: 0.875rem;
    font-weight: 600;
    z-index: 9999;
    opacity: 0;
    transform: translateY(12px);
    pointer-events: none;
    transition: all 0.25s ease;
}

.toast.is-show {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive */
@media (max-width: 992px) {
    .reader-layout {
        grid-template-columns: 1fr;
    }
    .reader-sidebar {
        display: none;
    }
}

@media (max-width: 768px) {
    .form-row {
        flex-direction: column;
    }
    .hero-title {
        font-size: 1.75rem;
    }
    .notes-grid {
        grid-template-columns: 1fr;
    }
}