/* ================================================================
   StudentOS — patches28.css
   1.  Attendance: hide patches27 additions (heat strip, streak badge,
       today button) so the calendar reverts to its patches26 state.
   2.  Worksheet: resize handles for every block.
   3.  Worksheet: unified Formula browser modal.
   4.  Worksheet: Checklist block.
   5.  Worksheet: Code block.
   6.  Worksheet: UX polish (empty state, picker additions).
   ================================================================ */

/* ================================================================
   1.  ATTENDANCE — UNDO PATCHES27
   ================================================================ */
.p27-heat-strip,
.p27-streak-badge,
.p27-today-btn {
    display: none !important;
}

/* ================================================================
   2.  WORKSHEET RESIZE HANDLES
   ================================================================ */
.p19-ws-block {
    position: relative;
}

.p28-resize-handle {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 8px;
    cursor: ns-resize;
    border-radius: 0 0 12px 12px;
    opacity: 0;
    transition: opacity .15s;
    background: linear-gradient(transparent, color-mix(in srgb, var(--accent) 22%, transparent));
    z-index: 5;
}
.p19-ws-block:hover .p28-resize-handle {
    opacity: 1;
}
.p28-resize-handle:hover,
.p28-resize-handle.dragging {
    opacity: 1;
    background: linear-gradient(transparent, color-mix(in srgb, var(--accent) 40%, transparent));
}
/* Grip dots on the handle */
.p28-resize-handle::after {
    content: '';
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    width: 28px;
    height: 3px;
    border-radius: 99px;
    background: var(--accent);
    opacity: 0.5;
}

/* ================================================================
   3.  FORMULA BROWSER MODAL
   ================================================================ */
#p28-formula-modal {
    position: fixed;
    inset: 0;
    z-index: 9900;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 0, 0, 0.55);
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    opacity: 0;
    pointer-events: none;
    transition: opacity .18s;
}
#p28-formula-modal.open {
    opacity: 1;
    pointer-events: all;
}

.p28-modal-box {
    display: flex;
    flex-direction: column;
    width: min(820px, 95vw);
    max-height: min(680px, 90vh);
    border-radius: 18px;
    background: var(--glass-panel);
    border: var(--glass-border);
    backdrop-filter: blur(40px);
    -webkit-backdrop-filter: blur(40px);
    box-shadow: 0 16px 64px rgba(0,0,0,.38);
    overflow: hidden;
}

.p28-modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 18px 20px 14px;
    border-bottom: 1px solid var(--glass-border);
    flex-shrink: 0;
}
.p28-modal-title {
    display: flex;
    align-items: center;
    gap: 9px;
    font-size: .95rem;
    font-weight: 700;
    color: var(--text-main);
}
.p28-modal-title i {
    color: var(--accent);
    font-size: 1rem;
}
.p28-modal-close-btn {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-muted);
    font-size: .9rem;
    padding: 4px 6px;
    border-radius: 7px;
    transition: background .12s, color .12s;
    line-height: 1;
}
.p28-modal-close-btn:hover {
    background: var(--glass-hover);
    color: var(--text-main);
}

.p28-modal-controls {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 20px;
    border-bottom: 1px solid var(--glass-border);
    flex-shrink: 0;
    flex-wrap: wrap;
}

.p28-modal-search-wrap {
    flex: 1;
    min-width: 160px;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 7px 12px;
    border-radius: 10px;
    border: 1px solid var(--glass-border);
    background: var(--glass-hover);
    transition: border-color .12s;
}
.p28-modal-search-wrap:focus-within {
    border-color: var(--accent);
}
.p28-modal-search-wrap i {
    color: var(--text-muted);
    font-size: .78rem;
    flex-shrink: 0;
}
.p28-modal-search-inp {
    flex: 1;
    background: none;
    border: none;
    outline: none;
    color: var(--text-main);
    font-size: .82rem;
    font-family: inherit;
}
.p28-modal-search-inp::placeholder {
    color: var(--text-muted);
    opacity: .7;
}

.p28-modal-subject-sel {
    padding: 7px 10px;
    border-radius: 10px;
    border: 1px solid var(--glass-border);
    background: var(--glass-hover);
    color: var(--text-main);
    font-size: .8rem;
    font-family: inherit;
    cursor: pointer;
    outline: none;
}
.p28-modal-subject-sel:focus {
    border-color: var(--accent);
}

/* Tabs: Built-in / My formulas */
.p28-modal-tabs {
    display: flex;
    gap: 2px;
    padding: 0 20px;
    border-bottom: 1px solid var(--glass-border);
    flex-shrink: 0;
}
.p28-modal-tab {
    padding: 8px 14px;
    font-size: .78rem;
    font-weight: 600;
    color: var(--text-muted);
    background: none;
    border: none;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -1px;
    transition: color .12s, border-color .12s;
    font-family: inherit;
}
.p28-modal-tab:hover {
    color: var(--text-main);
}
.p28-modal-tab.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

/* Formula grid */
.p28-formula-grid {
    flex: 1;
    overflow-y: auto;
    padding: 16px 20px 20px;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 10px;
    align-content: start;
}
.p28-formula-grid::-webkit-scrollbar { width: 5px; }
.p28-formula-grid::-webkit-scrollbar-track { background: transparent; }
.p28-formula-grid::-webkit-scrollbar-thumb { background: var(--glass-border); border-radius: 99px; }

.p28-fml-card {
    padding: 12px 14px;
    border-radius: 12px;
    border: 1px solid var(--glass-border);
    background: var(--glass-panel);
    cursor: pointer;
    transition: border-color .12s, background .12s, transform .1s;
    display: flex;
    flex-direction: column;
    gap: 5px;
}
.p28-fml-card:hover {
    border-color: var(--accent);
    background: color-mix(in srgb, var(--accent) 8%, var(--glass-panel));
    transform: translateY(-1px);
}
.p28-fml-card:active { transform: translateY(0); }

.p28-fml-card-badges {
    display: flex;
    align-items: center;
    gap: 5px;
    flex-wrap: wrap;
}
.p28-fml-subj-badge {
    font-size: .62rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .04em;
    padding: 2px 7px;
    border-radius: 99px;
    background: color-mix(in srgb, var(--accent) 14%, transparent);
    color: var(--accent);
    border: 1px solid color-mix(in srgb, var(--accent) 25%, transparent);
}
.p28-fml-mine-badge {
    font-size: .62rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .04em;
    padding: 2px 7px;
    border-radius: 99px;
    background: color-mix(in srgb, #22c55e 14%, transparent);
    color: #22c55e;
    border: 1px solid color-mix(in srgb, #22c55e 25%, transparent);
}
.p28-fml-card-title {
    font-size: .82rem;
    font-weight: 600;
    color: var(--text-main);
    line-height: 1.3;
}
.p28-fml-card-expr {
    font-size: .72rem;
    font-family: 'JetBrains Mono', monospace;
    color: var(--text-muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
.p28-fml-card-add-row {
    margin-top: 4px;
    display: flex;
    justify-content: flex-end;
}
.p28-fml-card-add-btn {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: .7rem;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: 7px;
    border: 1px solid var(--glass-border);
    background: var(--glass-hover);
    color: var(--text-muted);
    cursor: pointer;
    font-family: inherit;
    transition: border-color .12s, color .12s, background .12s;
}
.p28-fml-card:hover .p28-fml-card-add-btn {
    border-color: var(--accent);
    color: var(--accent);
    background: color-mix(in srgb, var(--accent) 12%, transparent);
}

.p28-formula-grid-empty {
    grid-column: 1 / -1;
    text-align: center;
    padding: 40px 20px;
    font-size: .82rem;
    color: var(--text-muted);
}

/* "Formulas" button in picker */
.p28-picker-formula-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    padding: 12px 8px 10px;
    border-radius: 10px;
    border: 1px solid var(--glass-border);
    background: color-mix(in srgb, var(--accent) 7%, var(--glass-hover));
    color: var(--text-main);
    font-size: .72rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: border-color .12s, background .12s;
    text-align: center;
}
.p28-picker-formula-btn:hover {
    border-color: var(--accent);
    background: color-mix(in srgb, var(--accent) 14%, transparent);
    color: var(--accent);
}
.p28-picker-formula-btn i {
    font-size: .9rem;
}

/* ================================================================
   4.  CHECKLIST BLOCK
   ================================================================ */
.p28-checklist-block {
    display: flex;
    flex-direction: column;
    gap: 8px;
    overflow: hidden;
}

.p28-checklist-title-inp {
    width: 100%;
    background: none;
    border: none;
    outline: none;
    border-bottom: 1px solid var(--glass-border);
    color: var(--text-main);
    font-family: inherit;
    font-size: .88rem;
    font-weight: 600;
    padding: 4px 2px 6px;
    margin-bottom: 4px;
    transition: border-color .12s;
}
.p28-checklist-title-inp:focus { border-bottom-color: var(--accent); }
.p28-checklist-title-inp::placeholder { color: var(--text-muted); opacity: .6; }

.p28-checklist-items {
    display: flex;
    flex-direction: column;
    gap: 4px;
}
.p28-checklist-item {
    display: flex;
    align-items: center;
    gap: 9px;
}
.p28-checklist-item-cb {
    flex-shrink: 0;
    width: 16px;
    height: 16px;
    border-radius: 4px;
    border: 2px solid var(--glass-border);
    appearance: none;
    -webkit-appearance: none;
    background: transparent;
    cursor: pointer;
    position: relative;
    transition: background .12s, border-color .12s;
}
.p28-checklist-item-cb:checked {
    background: var(--accent);
    border-color: var(--accent);
}
.p28-checklist-item-cb:checked::after {
    content: '\f00c';
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
    position: absolute;
    font-size: .6rem;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #fff;
}
.p28-checklist-item-text {
    flex: 1;
    background: none;
    border: none;
    outline: none;
    color: var(--text-main);
    font-family: inherit;
    font-size: .82rem;
    padding: 4px 0;
    border-bottom: 1px solid transparent;
    transition: border-color .12s;
}
.p28-checklist-item-text:focus { border-bottom-color: var(--glass-border); }
.p28-checklist-item-text.done {
    text-decoration: line-through;
    opacity: .55;
}
.p28-checklist-item-del {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-muted);
    font-size: .72rem;
    padding: 3px 5px;
    border-radius: 5px;
    opacity: 0;
    transition: opacity .12s, color .12s, background .12s;
    flex-shrink: 0;
}
.p28-checklist-item:hover .p28-checklist-item-del { opacity: 1; }
.p28-checklist-item-del:hover {
    color: #ef4444;
    background: color-mix(in srgb, #ef4444 14%, transparent);
}

.p28-checklist-add-btn {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 5px 11px;
    border-radius: 8px;
    border: 1px dashed var(--glass-border);
    background: none;
    color: var(--text-muted);
    font-size: .75rem;
    font-family: inherit;
    cursor: pointer;
    transition: border-color .12s, color .12s;
    align-self: flex-start;
    margin-top: 2px;
}
.p28-checklist-add-btn:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.p28-checklist-stats {
    font-size: .7rem;
    color: var(--text-muted);
    margin-top: 2px;
}

/* ================================================================
   5.  CODE BLOCK
   ================================================================ */
.p28-code-block {
    display: flex;
    flex-direction: column;
    gap: 0;
    overflow: hidden;
}

.p28-code-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 7px 12px;
    border-bottom: 1px solid var(--glass-border);
    background: color-mix(in srgb, var(--glass-border) 40%, transparent);
    border-radius: 8px 8px 0 0;
}
.p28-code-lang-sel {
    background: none;
    border: none;
    outline: none;
    color: var(--text-muted);
    font-size: .72rem;
    font-family: 'JetBrains Mono', monospace;
    cursor: pointer;
}
.p28-code-copy-btn {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: .7rem;
    font-family: inherit;
    padding: 3px 9px;
    border-radius: 6px;
    border: 1px solid var(--glass-border);
    background: var(--glass-hover);
    color: var(--text-muted);
    cursor: pointer;
    transition: border-color .12s, color .12s;
}
.p28-code-copy-btn:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.p28-code-textarea {
    width: 100%;
    min-height: 100px;
    padding: 14px 16px;
    background: color-mix(in srgb, var(--bg-color) 70%, transparent);
    border: none;
    outline: none;
    resize: none;
    color: var(--text-main);
    font-family: 'JetBrains Mono', monospace;
    font-size: .8rem;
    line-height: 1.6;
    tab-size: 2;
    border-radius: 0 0 8px 8px;
    box-sizing: border-box;
}
.p28-code-textarea::placeholder { color: var(--text-muted); opacity: .5; }

/* ================================================================
   6.  UX POLISH
   ================================================================ */
/* Keyboard shortcut hint below the add button */
#p28-ws-shortcut-hint {
    text-align: center;
    font-size: .68rem;
    color: var(--text-muted);
    opacity: .5;
    margin-top: -4px;
    pointer-events: none;
    user-select: none;
}
/* Empty state */
#p28-ws-empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    padding: 48px 24px;
    color: var(--text-muted);
    text-align: center;
    pointer-events: none;
    user-select: none;
}
#p28-ws-empty-state i {
    font-size: 2rem;
    opacity: .3;
}
#p28-ws-empty-state p {
    font-size: .82rem;
    opacity: .55;
    max-width: 260px;
    line-height: 1.5;
    margin: 0;
}