/* ═══════════════════════════════════════════════
   DESIGN TOKENS
═══════════════════════════════════════════════ */
:root {
    --bg: #0f0f11;
    --surface: #1a1a1f;
    --surface2: #222228;
    --surface3: #2c2c34;
    --border: #2e2e38;
    --border-light: #3a3a46;

    --text-1: #f0f0f5;
    --text-2: #9898a8;
    --text-3: #5e5e72;

    --accent: #7c6ef0;
    --accent-dim: rgba(124, 110, 240, 0.18);
    --accent-hover: #9585f5;

    --success: #34d399;
    --success-dim: rgba(52, 211, 153, 0.15);
    --danger: #f87171;
    --danger-dim: rgba(248, 113, 113, 0.15);
    --warn: #fb923c;
    --warn-dim: rgba(251, 146, 60, 0.15);
    --yellow: #fbbf24;
    --yellow-dim: rgba(251, 191, 36, 0.12);

    --sheet-radius: 24px;
    --radius: 14px;
    --radius-sm: 8px;

    --shadow-fab: 0 8px 32px rgba(124, 110, 240, 0.45);
    --shadow-sheet: 0 -8px 40px rgba(0,0,0,0.6);

    --transition: 0.28s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ═══════════════════════════════════════════════
   RESET
═══════════════════════════════════════════════ */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-tap-highlight-color: transparent;
}

html, body {
    height: 100%;
    overscroll-behavior: none;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    color: var(--text-1);
    min-height: 100svh;
    line-height: 1.5;
    overflow-x: hidden;
}

.sr-only {
    position: absolute;
    width: 1px; height: 1px;
    padding: 0; margin: -1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    white-space: nowrap;
    border: 0;
}

/* ═══════════════════════════════════════════════
   APP SHELL
═══════════════════════════════════════════════ */
.app-shell {
    display: flex;
    flex-direction: column;
    min-height: 100svh;
    max-width: 480px;
    margin: 0 auto;
    padding-bottom: 100px; /* room for FAB */
}

/* ═══════════════════════════════════════════════
   TOP BAR
═══════════════════════════════════════════════ */
.topbar {
    position: sticky;
    top: 0;
    z-index: 50;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px 12px;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
}

.topbar-left {
    display: flex;
    align-items: center;
    gap: 10px;
}

.app-logo {
    font-size: 1.6rem;
    line-height: 1;
}

.app-title {
    font-size: 1.35rem;
    font-weight: 700;
    letter-spacing: -0.04em;
    color: var(--text-1);
    line-height: 1.1;
}

.app-sub {
    font-size: 0.72rem;
    color: var(--text-3);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-top: 1px;
}

.icon-pill {
    display: flex;
    align-items: center;
    gap: 6px;
    background: var(--surface2);
    border: 1px solid var(--border);
    color: var(--text-2);
    padding: 7px 14px;
    border-radius: 50px;
    font-size: 0.82rem;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition);
}
.icon-pill:hover, .icon-pill:active {
    background: var(--surface3);
    color: var(--text-1);
}

/* ═══════════════════════════════════════════════
   FILTER BAR
═══════════════════════════════════════════════ */
.filter-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 14px 20px;
    background: var(--bg);
}

.filter-tabs {
    display: flex;
    gap: 4px;
    background: var(--surface);
    border-radius: 50px;
    padding: 4px;
    border: 1px solid var(--border);
}

.filter-tab {
    background: transparent;
    border: none;
    color: var(--text-2);
    padding: 6px 16px;
    border-radius: 50px;
    font-size: 0.84rem;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition);
    white-space: nowrap;
}

.filter-tab.active {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 2px 12px rgba(124, 110, 240, 0.4);
}

.chip-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    background: var(--surface);
    border: 1px solid var(--border);
    color: var(--text-2);
    padding: 7px 12px;
    border-radius: 50px;
    font-size: 0.82rem;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition);
    white-space: nowrap;
    max-width: 140px;
    overflow: hidden;
    text-overflow: ellipsis;
}
.chip-btn:hover { background: var(--surface2); color: var(--text-1); }
.chip-btn span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* ═══════════════════════════════════════════════
   TASK FEED
═══════════════════════════════════════════════ */
.feed {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding: 8px 16px 20px;
}

.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 60px 20px;
    color: var(--text-3);
    text-align: center;
}
.empty-state .empty-icon { font-size: 3rem; }
.empty-state p { font-size: 0.9rem; }

/* ═══════════════════════════════════════════════
   HW ITEM CARD
═══════════════════════════════════════════════ */
.hw-item {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 14px 16px;
    display: flex;
    align-items: flex-start;
    gap: 12px;
    transition: transform 0.18s ease, box-shadow 0.18s ease;
    animation: slideUp 0.25s ease both;
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(14px); }
    to   { opacity: 1; transform: translateY(0); }
}

.hw-item:active { transform: scale(0.98); }

.hw-item.urgency-high {
    border-color: var(--danger);
    background: linear-gradient(135deg, var(--surface) 60%, var(--danger-dim));
}
.hw-item.urgency-med {
    border-color: var(--warn);
    background: linear-gradient(135deg, var(--surface) 60%, var(--warn-dim));
}
.hw-item.urgency-low {
    border-color: var(--yellow);
    background: linear-gradient(135deg, var(--surface) 60%, var(--yellow-dim));
}
.hw-item.completed {
    opacity: 0.5;
    background: var(--bg);
}

.hw-check {
    flex-shrink: 0;
    width: 26px; height: 26px;
    border-radius: 50%;
    border: 2px solid var(--border-light);
    background: transparent;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition);
    color: transparent;
    font-size: 0.85rem;
    margin-top: 1px;
}
.hw-item.completed .hw-check {
    background: var(--success);
    border-color: var(--success);
    color: #000;
}
.hw-check:hover { border-color: var(--success); }

.hw-info { flex: 1; min-width: 0; }

.hw-meta {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    margin-bottom: 6px;
}

.subject-badge {
    background: var(--accent-dim);
    color: var(--accent-hover);
    border: 1px solid rgba(124,110,240,0.3);
    padding: 2px 9px;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.02em;
}

.date-badge {
    font-size: 0.78rem;
    color: var(--text-3);
    font-weight: 500;
}
.date-badge.overdue { color: var(--danger); font-weight: 600; }

.hw-tasks {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 3px;
}
.hw-tasks li {
    font-size: 0.9rem;
    color: var(--text-2);
    padding-left: 12px;
    position: relative;
}
.hw-tasks li::before {
    content: '–';
    position: absolute;
    left: 0;
    color: var(--text-3);
}
.hw-item.completed .hw-tasks li {
    text-decoration: line-through;
    color: var(--text-3);
}

.hw-delete {
    flex-shrink: 0;
    background: transparent;
    border: none;
    color: var(--text-3);
    cursor: pointer;
    padding: 4px;
    border-radius: 6px;
    transition: all var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}
.hw-delete:hover { color: var(--danger); background: var(--danger-dim); }

/* ═══════════════════════════════════════════════
   FAB
═══════════════════════════════════════════════ */
.fab {
    position: fixed;
    bottom: 28px;
    right: 50%;
    transform: translateX(50%);
    width: 62px; height: 62px;
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-fab);
    transition: transform 0.2s ease, background 0.2s ease;
    z-index: 100;
}
.fab:hover { background: var(--accent-hover); transform: translateX(50%) scale(1.07); }
.fab:active { transform: translateX(50%) scale(0.94); }

/* ═══════════════════════════════════════════════
   SHEET OVERLAY + BOTTOM SHEET
═══════════════════════════════════════════════ */
.sheet-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.65);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    z-index: 200;
    display: flex;
    align-items: flex-end;
    transition: opacity var(--transition);
}
.sheet-overlay.hidden {
    opacity: 0;
    pointer-events: none;
}
.sheet-overlay.hidden .bottom-sheet {
    transform: translateY(100%);
}

.bottom-sheet {
    width: 100%;
    max-width: 480px;
    margin: 0 auto;
    background: var(--surface);
    border-radius: var(--sheet-radius) var(--sheet-radius) 0 0;
    box-shadow: var(--shadow-sheet);
    transition: transform var(--transition);
    max-height: 92svh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.picker-sheet { max-height: 70svh; }
.manage-sheet { max-height: 80svh; }

.sheet-handle {
    width: 40px; height: 4px;
    background: var(--border-light);
    border-radius: 99px;
    margin: 12px auto 4px;
    flex-shrink: 0;
}

.sheet-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 20px 14px;
    flex-shrink: 0;
    border-bottom: 1px solid var(--border);
}

.sheet-title {
    font-size: 1.05rem;
    font-weight: 650;
    letter-spacing: -0.02em;
    color: var(--text-1);
}

.close-btn {
    background: var(--surface2);
    border: none;
    color: var(--text-2);
    width: 32px; height: 32px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition);
}
.close-btn:hover { background: var(--surface3); color: var(--text-1); }

.sheet-body {
    overflow-y: auto;
    padding: 18px 20px 32px;
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* ═══════════════════════════════════════════════
   FORM ELEMENTS
═══════════════════════════════════════════════ */
#hw-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.field-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.field-label {
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--text-3);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.text-input {
    width: 100%;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-1);
    font-family: inherit;
    font-size: 0.95rem;
    padding: 12px 14px;
    outline: none;
    transition: border-color var(--transition), box-shadow var(--transition);
}
.text-input::placeholder { color: var(--text-3); }
.text-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-dim);
}

.date-input {
    width: 100%;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-1);
    font-family: inherit;
    font-size: 0.95rem;
    padding: 12px 14px;
    outline: none;
    cursor: pointer;
    transition: border-color var(--transition), box-shadow var(--transition);
}
.date-input::placeholder { color: var(--text-3); }
.date-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-dim);
}

.field-row { display: flex; gap: 8px; }

/* Custom Select Button */
.custom-select-wrap { display: flex; }
.custom-select-btn {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-1);
    font-family: inherit;
    font-size: 0.95rem;
    padding: 12px 14px;
    cursor: pointer;
    text-align: left;
    transition: border-color var(--transition), box-shadow var(--transition);
}
.custom-select-btn:hover { border-color: var(--border-light); }
.custom-select-btn:focus-visible {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-dim);
}
.custom-select-btn svg { flex-shrink: 0; color: var(--text-3); }
.custom-select-btn span {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}
.custom-select-btn span.placeholder { color: var(--text-3); }

/* Task builder row */
.task-builder-row {
    display: flex;
    gap: 8px;
    align-items: stretch;
}
.task-builder-row .flex-1 { flex: 1; }

.icon-add-btn {
    flex-shrink: 0;
    width: 46px;
    background: var(--accent);
    border: none;
    border-radius: var(--radius-sm);
    color: #fff;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background var(--transition), transform 0.15s ease;
}
.icon-add-btn:hover { background: var(--accent-hover); }
.icon-add-btn:active { transform: scale(0.92); }

.task-input-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.task-input-group.hidden { display: none; }

/* Staged tasks list */
.staged-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 6px;
}
.staged-list li {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 9px 12px;
    font-size: 0.88rem;
    color: var(--text-1);
    animation: slideUp 0.2s ease both;
}
.staged-list li span { flex: 1; }
.staged-list li button {
    background: transparent;
    border: none;
    color: var(--text-3);
    cursor: pointer;
    font-size: 1rem;
    line-height: 1;
    padding: 2px;
    transition: color var(--transition);
}
.staged-list li button:hover { color: var(--danger); }

/* Submit button */
.submit-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    width: 100%;
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 0.98rem;
    font-weight: 600;
    padding: 14px;
    cursor: pointer;
    transition: background var(--transition), transform 0.15s ease;
    margin-top: 4px;
}
.submit-btn:hover { background: var(--accent-hover); }
.submit-btn:active { transform: scale(0.98); }

/* ═══════════════════════════════════════════════
   PICKER LIST (Subject / Task Type)
═══════════════════════════════════════════════ */
.picker-list {
    overflow-y: auto;
    padding: 8px 16px 28px;
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.picker-option {
    width: 100%;
    text-align: left;
    background: transparent;
    border: 1px solid transparent;
    border-radius: var(--radius-sm);
    color: var(--text-1);
    font-family: inherit;
    font-size: 0.95rem;
    padding: 13px 16px;
    cursor: pointer;
    transition: all var(--transition);
    display: flex;
    align-items: center;
    gap: 10px;
}
.picker-option:hover { background: var(--surface2); border-color: var(--border); }
.picker-option.active {
    background: var(--accent-dim);
    border-color: rgba(124,110,240,0.35);
    color: var(--accent-hover);
    font-weight: 600;
}
.picker-option .check-icon {
    margin-left: auto;
    color: var(--accent);
    display: none;
}
.picker-option.active .check-icon { display: block; }

/* ═══════════════════════════════════════════════
   MANAGE SUBJECTS MODAL
═══════════════════════════════════════════════ */
.add-subject-form {
    display: flex;
    gap: 8px;
}

.small-add-btn {
    flex-shrink: 0;
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 0.9rem;
    font-weight: 600;
    padding: 0 18px;
    cursor: pointer;
    transition: background var(--transition);
}
.small-add-btn:hover { background: var(--accent-hover); }

.subjects-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
    margin-top: 4px;
    max-height: 300px;
    overflow-y: auto;
}

.subject-list-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 10px 14px;
    font-size: 0.92rem;
    color: var(--text-1);
}
.subject-list-item button {
    background: transparent;
    border: none;
    color: var(--text-3);
    cursor: pointer;
    font-size: 1rem;
    line-height: 1;
    padding: 3px 5px;
    border-radius: 4px;
    transition: all var(--transition);
}
.subject-list-item button:hover { color: var(--danger); background: var(--danger-dim); }

/* ═══════════════════════════════════════════════
   DATE DISPLAY ROW
═══════════════════════════════════════════════ */
.date-display-row {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--surface2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 10px 14px;
    color: var(--text-2);
    font-size: 0.9rem;
}
.date-display-row svg { flex-shrink: 0; color: var(--text-3); }
.date-display-row span { flex: 1; }
.date-display-placeholder { color: var(--text-3); }
.date-selected-label { color: var(--accent-hover); font-weight: 600; }

.clear-date-btn {
    background: transparent;
    border: none;
    color: var(--text-3);
    cursor: pointer;
    font-size: 0.85rem;
    padding: 2px 5px;
    border-radius: 4px;
    transition: color var(--transition);
}
.clear-date-btn:hover { color: var(--danger); }
.clear-date-btn.hidden { display: none; }

/* ═══════════════════════════════════════════════
   INLINE FLATPICKR CALENDAR (dark)
═══════════════════════════════════════════════ */
#inline-calendar {
    display: flex;
    justify-content: center;
}
#inline-calendar .flatpickr-calendar {
    width: 100% !important;
    max-width: 340px;
}
.flatpickr-calendar.inline {
    display: block !important;
    position: static !important;
    opacity: 1 !important;
    visibility: visible !important;
    background: var(--surface2) !important;
    border: 1px solid var(--border) !important;
    border-radius: var(--radius) !important;
    box-shadow: none !important;
    font-family: 'Inter', sans-serif !important;
    width: 100% !important;
    margin-top: 4px;
}
.flatpickr-months {
    background: transparent !important;
    padding: 6px 4px 4px !important;
}
.flatpickr-months .flatpickr-month {
    background: transparent !important;
    color: var(--text-1) !important;
    height: 36px !important;
}
.flatpickr-current-month {
    color: var(--text-1) !important;
    font-size: 1rem !important;
    font-weight: 600 !important;
    font-family: 'Inter', sans-serif !important;
    padding-top: 6px !important;
}
.flatpickr-current-month select,
.flatpickr-current-month input.numInput {
    color: var(--text-1) !important;
    background: transparent !important;
    font-family: 'Inter', sans-serif !important;
    font-weight: 600 !important;
}
.flatpickr-months .flatpickr-prev-month,
.flatpickr-months .flatpickr-next-month {
    color: var(--text-2) !important;
    fill: var(--text-2) !important;
    top: 8px !important;
}
.flatpickr-months .flatpickr-prev-month:hover,
.flatpickr-months .flatpickr-next-month:hover {
    color: var(--accent) !important;
    fill: var(--accent) !important;
    background: transparent !important;
}
.flatpickr-months .flatpickr-prev-month svg,
.flatpickr-months .flatpickr-next-month svg {
    fill: inherit !important;
}
.flatpickr-weekdays {
    background: transparent !important;
    padding: 0 4px !important;
}
.flatpickr-weekday {
    background: transparent !important;
    color: var(--text-3) !important;
    font-size: 0.75rem !important;
    font-weight: 600 !important;
    font-family: 'Inter', sans-serif !important;
}
.flatpickr-days { border: none !important; width: 100% !important; }
.dayContainer { width: 100% !important; min-width: 100% !important; max-width: 100% !important; }
.flatpickr-day {
    color: var(--text-1) !important;
    border-radius: 8px !important;
    font-family: 'Inter', sans-serif !important;
    font-size: 0.88rem !important;
    height: 36px !important;
    line-height: 36px !important;
    flex-basis: 14.2857% !important;
    max-width: 14.2857% !important;
    border: 1px solid transparent !important;
}
.flatpickr-day:hover {
    background: var(--surface3) !important;
    border-color: var(--border-light) !important;
    color: var(--text-1) !important;
}
.flatpickr-day.selected,
.flatpickr-day.selected:hover {
    background: var(--accent) !important;
    border-color: var(--accent) !important;
    color: #fff !important;
    box-shadow: 0 2px 8px rgba(124,110,240,0.45) !important;
}
.flatpickr-day.today {
    border-color: var(--accent) !important;
    color: var(--accent-hover) !important;
    font-weight: 600 !important;
}
.flatpickr-day.today.selected { color: #fff !important; }
.flatpickr-day.disabled,
.flatpickr-day.prevMonthDay,
.flatpickr-day.nextMonthDay {
    color: var(--text-3) !important;
    opacity: 0.5;
}
.flatpickr-day.flatpickr-disabled {
    color: var(--text-3) !important;
    cursor: not-allowed !important;
}
.numInputWrapper { background: transparent !important; }
.numInput { color: var(--text-1) !important; background: transparent !important; }
.numInputWrapper span { border-color: var(--border) !important; }
.numInputWrapper span:hover { background: var(--surface3) !important; }

/* ═══════════════════════════════════════════════
   SCROLLBAR
═══════════════════════════════════════════════ */
::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-light); border-radius: 4px; }