/* ============================================================
   MY LIBRARY APP — International Typographic Style
   ------------------------------------------------------------
   System: white paper, ink, hairlines, one functional accent.
   Signature: the red index rule — a single vermilion rule that
   always means "you are here" (active shelf, current view,
   flashcard answer). Nothing decorative; structure is state.
   ============================================================ */

:root {
    --paper:    #ffffff;
    --ink:      #111111;
    --hairline: #e2e2e2;
    --meta:     #6e6e6e;
    --field:    #f6f6f6;
    --accent:   #e1251b;   /* vermilion — functional only */
    --ok:       #0b7a3e;   /* functional green (quiz correct) */

    --font: "Neue Haas Grotesk Text Pro", "Helvetica Neue", Helvetica, Arial, sans-serif;
    --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;

    --u: 8px;              /* base spatial unit */
    --rule: 4px;           /* the index rule thickness */
}

* { box-sizing: border-box; }

body {
    font-family: var(--font);
    font-size: 15px;
    line-height: 1.5;
    background: var(--paper);
    color: var(--ink);
    margin: 0;
    height: 100vh;
    display: flex;
}

.hidden { display: none !important; }

:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------- Utility type roles ---------- */
.nav-header, .card-path, .progress-text, .version-tag, .flip-hint {
    font-size: 11px;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--meta);
    font-weight: 500;
}

/* ---------- Start screen ---------- */
.screen-centered {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: calc(var(--u) * 3);
}
.screen-centered h1 {
    font-size: 32px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin: 0 0 calc(var(--u) * 4);
    border-top: var(--rule) solid var(--accent);
    padding-top: calc(var(--u) * 2);
}
.drop-zone {
    border: 1px solid var(--ink);
    padding: calc(var(--u) * 5);
    text-align: center;
    background: var(--paper);
    width: 100%;
    max-width: 480px;
    cursor: pointer;
    transition: background 120ms;
}
.drop-zone.dragover { background: var(--field); border-color: var(--accent); }
.drop-zone p { margin: calc(var(--u)) 0; }
.drop-zone b { font-weight: 700; }

/* ---------- Layout ---------- */
#library-interface { display: flex; width: 100%; height: 100%; }

.sidebar {
    width: 264px;
    background: var(--paper);
    padding: calc(var(--u) * 3);
    border-right: 1px solid var(--hairline);
    display: flex;
    flex-direction: column;
}
.sidebar h2 {
    font-size: 24px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin: 0 0 calc(var(--u) * 2);
}

#search-bar {
    width: 100%;
    padding: calc(var(--u)) 0;
    border: 0;
    border-bottom: 1px solid var(--ink);
    background: transparent;
    font: inherit;
    margin-bottom: calc(var(--u) * 3);
    border-radius: 0;
}
#search-bar:focus { outline: none; border-bottom: 2px solid var(--accent); margin-bottom: calc(var(--u) * 3 - 1px); }
#search-bar::placeholder { color: var(--meta); }

.nav-header { margin-bottom: calc(var(--u)); }

.shelf-list { list-style: none; padding: 0; margin: 0; }
.shelf-list li {
    padding: calc(var(--u)) calc(var(--u) * 1.5);
    border-left: var(--rule) solid transparent;
    cursor: pointer;
    margin-bottom: 2px;
    transition: background 120ms, border-color 120ms;
}
.shelf-list li:hover { background: var(--field); }
.shelf-list li.active {
    border-left-color: var(--accent);   /* the index rule */
    background: var(--field);
    font-weight: 700;
}

.version-tag { margin: calc(var(--u) * 2) 0 0; text-align: left; }

.main-content {
    flex-grow: 1;
    padding: calc(var(--u) * 4);
    overflow-y: auto;
}

.library-header { margin-bottom: calc(var(--u) * 3); }
#current-view-title {
    font-size: 24px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin: 0;
    border-top: var(--rule) solid var(--accent);   /* the index rule */
    padding-top: calc(var(--u) * 1.5);
    display: inline-block;
    min-width: 200px;
}

/* ---------- Card grid ---------- */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: calc(var(--u) * 3);
}
.card {
    background: var(--paper);
    border: 1px solid var(--hairline);
    overflow: hidden;
    cursor: pointer;
    transition: border-color 120ms;
}
.card:hover { border-color: var(--ink); }
.card-image { width: 100%; height: 140px; object-fit: cover; background: var(--field); display: block; }
.card-content { padding: calc(var(--u) * 2); }
.card-path { display: block; margin-bottom: calc(var(--u) * 0.5); }   /* eyebrow above title */
.card-title { margin: 0; font-size: 15px; font-weight: 700; line-height: 1.3; }

/* ---------- Modals ---------- */
.modal {
    position: fixed; inset: 0;
    background: rgba(17, 17, 17, 0.5);
    display: flex; align-items: center; justify-content: center;
    z-index: 1000;
}
.modal-content {
    background: var(--paper);
    width: 90%; max-width: 760px; max-height: 90vh;
    border: 1px solid var(--ink);
    position: relative;
    overflow-y: auto;
    padding: calc(var(--u) * 4);
    padding-top: calc(var(--u) * 5);
}
.modal-content h2 { font-size: 24px; font-weight: 700; letter-spacing: -0.02em; }
.close-btn {
    position: absolute; top: calc(var(--u) * 2); right: calc(var(--u) * 2);
    background: var(--paper); border: 1px solid var(--ink);
    width: 32px; height: 32px;
    font-size: 16px; line-height: 1; cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    color: var(--ink); transition: background 120ms; z-index: 10;
}
.close-btn:hover { background: var(--ink); color: var(--paper); }
.ref-cover-image { width: 100%; max-height: 300px; object-fit: cover; margin-bottom: calc(var(--u) * 2); display: block; }

/* ---------- Buttons ---------- */
.btn {
    padding: calc(var(--u) * 1.25) calc(var(--u) * 2);
    border: 1px solid var(--ink);
    font-family: var(--font);
    font-size: 12.5px;
    font-weight: 500;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    cursor: pointer;
    background: var(--paper);
    color: var(--ink);
    transition: background 120ms, color 120ms;
    border-radius: 0;
}
.btn.primary { background: var(--ink); color: var(--paper); }
.btn.primary:hover { background: var(--accent); border-color: var(--accent); }
.btn.secondary:hover { background: var(--field); }
.btn.large { width: 100%; margin-top: calc(var(--u) * 2); padding: calc(var(--u) * 2); font-size: 13px; }
.btn:disabled { opacity: 0.5; cursor: default; }

.btn-small {
    padding: 4px 10px;
    font-size: 11px;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    border: 1px solid var(--ink);
    background: var(--paper);
    color: var(--ink);
    cursor: pointer;
    transition: background 120ms, color 120ms;
}
.btn-small:hover, .btn-small.view:hover, .btn-small.edit:hover, .btn-small.dup:hover { background: var(--ink); color: var(--paper); }
.btn-small.view, .btn-small.edit, .btn-small.dup { background: var(--paper); color: var(--ink); }

/* ---------- Full-screen modes (Process / Testing) ---------- */
.fullscreen-mode {
    position: fixed; inset: 0;
    background: var(--paper);
    z-index: 3000;
    display: flex; flex-direction: column;
}
.process-header {
    display: flex; justify-content: space-between; align-items: center;
    padding: calc(var(--u) * 2) calc(var(--u) * 3);
    border-bottom: 1px solid var(--hairline);
}
.process-body {
    flex-grow: 1; display: flex; align-items: center; justify-content: center;
    padding: calc(var(--u) * 3); overflow-y: auto;
}
.step-content {
    background: var(--paper);
    padding: calc(var(--u) * 5);
    border: 1px solid var(--ink);
    width: 100%; max-width: 600px;
    text-align: left; font-size: 18px; line-height: 1.55;
}
.step-content h2 { letter-spacing: -0.02em; }
.step-input-group { margin-top: calc(var(--u) * 4); }
.step-input-group label { display: block; font-size: 13px; margin-bottom: calc(var(--u)); color: var(--meta); }
.step-input-group input, .step-input-group textarea {
    width: 100%; padding: calc(var(--u) * 1.5) 0;
    border: 0; border-bottom: 1px solid var(--ink);
    font: inherit; background: transparent; border-radius: 0;
}
.step-input-group input:focus, .step-input-group textarea:focus { outline: none; border-bottom: 2px solid var(--accent); }
.process-footer {
    display: flex; justify-content: space-between;
    padding: calc(var(--u) * 2) calc(var(--u) * 3);
    border-top: 1px solid var(--hairline); background: var(--paper);
}

/* ---------- Reports ---------- */
.report-table { width: 100%; border-collapse: collapse; margin-top: calc(var(--u) * 2); }
.report-table th, .report-table td { border: 1px solid var(--hairline); padding: calc(var(--u) * 1.5); text-align: left; }
.report-table th { background: var(--field); font-size: 12px; letter-spacing: 0.06em; text-transform: uppercase; }

.past-reports-list { list-style: none; padding: 0; margin: 0; }
.report-item {
    border: 1px solid var(--hairline);
    padding: calc(var(--u) * 2); margin-bottom: calc(var(--u));
    display: flex; justify-content: space-between; align-items: center;
}
.report-item-title { font-weight: 700; margin: 0; }
.report-item-date { font-size: 12px; color: var(--meta); margin: 4px 0 0; }
.report-item-actions { display: flex; gap: calc(var(--u) * 0.75); }

/* ---------- Testing: quiz ---------- */
.quiz-options { display: flex; flex-direction: column; gap: calc(var(--u)); margin-top: calc(var(--u) * 2); }
.btn-quiz {
    padding: calc(var(--u) * 2);
    border: 1px solid var(--ink);
    background: var(--paper); color: var(--ink);
    font: inherit; font-size: 15px; cursor: pointer;
    text-align: left; transition: background 120ms;
}
.btn-quiz:hover { background: var(--field); }
.btn-quiz.correct   { background: var(--ok); color: var(--paper); border-color: var(--ok); pointer-events: none; }
.btn-quiz.incorrect { background: var(--accent); color: var(--paper); border-color: var(--accent); pointer-events: none; }
.btn-quiz.disabled  { opacity: 0.5; pointer-events: none; }

/* ---------- Testing: flashcard ---------- */
.flip-card {
    background: transparent;
    width: 100%; max-width: 420px; height: 250px;
    perspective: 1000px;
    margin: 0 auto;
    cursor: pointer;
}
.flip-card-inner {
    position: relative; width: 100%; height: 100%;
    text-align: center;
    transition: transform 0.5s;
    transform-style: preserve-3d;
}
.flip-card.is-flipped .flip-card-inner { transform: rotateY(180deg); }
.flip-card-front, .flip-card-back {
    position: absolute; width: 100%; height: 100%;
    -webkit-backface-visibility: hidden; backface-visibility: hidden;
    display: flex; align-items: center; justify-content: center;
    padding: calc(var(--u) * 3);
    font-size: 22px; font-weight: 700; letter-spacing: -0.01em;
}
.flip-card-front { background: var(--paper); color: var(--ink); border: 1px solid var(--ink); }
.flip-card-back  { background: var(--accent); color: var(--paper); transform: rotateY(180deg); }   /* the index rule, fullbleed */
.flip-hint { text-align: center; margin-top: calc(var(--u) * 2); }
@media (prefers-reduced-motion: reduce) {
    .flip-card-inner { transition: none; }
}

/* ---------- Media & attachments ---------- */
.media-container { margin: calc(var(--u) * 2) 0; display: flex; flex-direction: column; gap: calc(var(--u)); }
audio { width: 100%; max-width: 420px; outline: none; }
video { width: 100%; max-height: 400px; background: var(--ink); margin-bottom: calc(var(--u)); outline: none; display: block; }
.iframe-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; margin-bottom: calc(var(--u)); }
.iframe-container iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
.attachment-link {
    display: inline-flex; align-items: center; gap: calc(var(--u));
    padding: calc(var(--u)) calc(var(--u) * 1.5);
    border: 1px solid var(--ink);
    color: var(--ink); text-decoration: none; font-size: 13px;
    transition: background 120ms, color 120ms;
}
.attachment-link:hover { background: var(--ink); color: var(--paper); }

/* ---------- Editor ---------- */
#json-editor {
    resize: vertical;
    font-family: var(--mono);
    font-size: 13px;
    border: 1px solid var(--ink) !important;
    border-radius: 0 !important;
    background: var(--field);
}

/* ---------- Help ---------- */
.help-content { max-width: 800px; width: 95%; }
.help-scroll-area { max-height: 60vh; overflow-y: auto; text-align: left; padding-right: calc(var(--u) * 2); margin-top: calc(var(--u) * 2); }
.help-scroll-area h3 {
    font-size: 15px; font-weight: 700;
    margin: calc(var(--u) * 4) 0 calc(var(--u) * 0.5);
    border-bottom: 1px solid var(--ink);
    padding-bottom: calc(var(--u) * 0.5);
}
.help-scroll-area p { margin-top: 0; color: var(--meta); font-size: 14px; }
.help-scroll-area pre {
    background: var(--ink); color: var(--field);
    padding: calc(var(--u) * 2);
    overflow-x: auto; font-family: var(--mono); font-size: 12.5px;
}

/* ---------- Checklists ---------- */
.checklist-container { border: 1px solid var(--hairline); padding: calc(var(--u) * 2); }
.checklist-item { display: flex; align-items: center; gap: calc(var(--u) * 1.5); margin-bottom: calc(var(--u) * 1.5); cursor: pointer; font-size: 15px; }
.checklist-item:last-child { margin-bottom: 0; }
.checklist-checkbox { width: 18px; height: 18px; cursor: pointer; accent-color: var(--ink); }
.checklist-text { transition: color 120ms; }
.checklist-text.completed { text-decoration: line-through; color: var(--meta); }

/* ---------- Media manager ---------- */
.media-list-container { max-height: 300px; overflow-y: auto; border: 1px solid var(--hairline); padding: calc(var(--u)); background: var(--paper); }
.media-item-row { display: flex; justify-content: space-between; align-items: center; padding: calc(var(--u)); border-bottom: 1px solid var(--hairline); }
.media-item-row:last-child { border-bottom: none; }
.media-filename { font-family: var(--mono); font-size: 12.5px; color: var(--ink); word-break: break-all; padding-right: calc(var(--u) * 2); }

/* ---------- Markdown & blocks ---------- */
.md-body h3, .md-body h4, .md-body h5 { margin: calc(var(--u) * 2.5) 0 calc(var(--u) * 0.75); letter-spacing: -0.01em; }
.md-body p { margin: calc(var(--u) * 1.25) 0; }
.md-body ul, .md-body ol { margin: calc(var(--u) * 1.25) 0; padding-left: calc(var(--u) * 3); line-height: 1.6; }
.md-body code, .md-code code { font-family: var(--mono); font-size: 0.9em; }
.md-body code { background: var(--field); padding: 1px 5px; }
.md-code {
    background: var(--ink); color: var(--field);
    padding: calc(var(--u) * 2);
    overflow-x: auto; margin: calc(var(--u) * 2) 0; position: relative;
    white-space: pre; text-align: left;
}
.md-code .code-lang {
    position: absolute; top: calc(var(--u)); right: calc(var(--u) * 1.5);
    font-size: 10px; color: var(--accent); text-transform: uppercase; letter-spacing: 0.08em;
}
.md-quote, .md-body blockquote {
    border-left: var(--rule) solid var(--ink);
    margin: calc(var(--u) * 2) 0; padding: calc(var(--u)) calc(var(--u) * 2);
    text-align: left;
}
.md-quote cite { display: block; margin-top: calc(var(--u)); font-style: normal; font-size: 13px; color: var(--meta); }
.md-callout { margin: calc(var(--u) * 2) 0; padding: calc(var(--u) * 1.5) calc(var(--u) * 2); border-left: var(--rule) solid var(--meta); background: var(--field); text-align: left; }
.md-callout.tip     { border-left-color: var(--ok); }
.md-callout.warning { border-left-color: var(--accent); }
.md-table { width: 100%; border-collapse: collapse; margin: calc(var(--u) * 2) 0; }
.md-table th, .md-table td { border: 1px solid var(--hairline); padding: calc(var(--u)) calc(var(--u) * 1.5); text-align: left; }
.md-table th { background: var(--field); font-size: 12px; letter-spacing: 0.06em; text-transform: uppercase; }

/* ---------- Mobile ---------- */
.mobile-menu-btn { display: none; }
.sidebar-overlay { display: none; }

@media (max-width: 768px) {
    .library-header { display: flex; align-items: center; margin-bottom: calc(var(--u) * 2); }
    .mobile-menu-btn {
        display: block; background: none; border: 0;
        font-size: 26px; cursor: pointer; margin-right: calc(var(--u) * 2);
        color: var(--ink); padding: 0;
    }
    .sidebar {
        position: fixed; top: 0; left: 0; height: 100%; width: 264px;
        z-index: 2000;
        transform: translateX(-100%);
        transition: transform 0.25s ease;
        border-right: 1px solid var(--ink);
        box-shadow: 8px 0 24px rgba(17,17,17,0.12);   /* depth is functional here */
    }
    .sidebar.open { transform: translateX(0); }
    .sidebar-overlay {
        display: block; position: fixed; inset: 0;
        background: rgba(17,17,17,0.4);
        z-index: 1500; opacity: 0; pointer-events: none;
        transition: opacity 0.25s ease;
    }
    .sidebar-overlay.open { opacity: 1; pointer-events: auto; }
    .main-content { padding: calc(var(--u) * 2); }
    .card-grid { grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: calc(var(--u) * 2); }
    .modal-content { width: 95%; padding: calc(var(--u) * 2.5); padding-top: calc(var(--u) * 5); margin-top: calc(var(--u) * 2); }
    @media (prefers-reduced-motion: reduce) {
        .sidebar, .sidebar-overlay { transition: none; }
    }
}

/* Report modal actions row (was inline-styled) */
.report-actions { margin-top: calc(var(--u) * 3); display: flex; gap: calc(var(--u)); border-top: 1px solid var(--hairline); padding-top: calc(var(--u) * 3); }