/* ==========================================================================
   COMPONENTS — Reusable UI Components
   Practice Hub · Academic Command Center
========================================================================== */

/* ── Styled Premium Select Dropdowns ── */
.styled-select-container {
    position: relative;
    width: 100%;
}
.styled-select {
    appearance: none;
    -webkit-appearance: none;
    width: 100%;
    background: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-primary);
    border-radius: var(--radius-md);
    padding: 1rem 1.25rem;
    font-family: var(--font-display);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    outline: none;
    transition: all 0.2s ease;
}
.styled-select:focus {
    border-color: var(--indigo-light);
    box-shadow: 0 0 0 3px var(--indigo-dim);
}
.styled-select option {
    background: var(--bg-surface);
    color: var(--text-primary);
}
.styled-select-container .select-icon {
    position: absolute;
    right: 1.25rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-tertiary);
    pointer-events: none;
    transition: 0.2s ease;
}
.styled-select:focus + .select-icon {
    color: var(--indigo-light);
    transform: translateY(-50%) rotate(180deg);
}

/* ── Horizontal Scrollable Pill Filters ── */
.filter-scroll-row {
    display: flex; gap: 0.5rem; overflow-x: auto; padding-bottom: 0.5rem;
    scroll-snap-type: x mandatory; -webkit-overflow-scrolling: touch; scrollbar-width: none; margin-bottom: 1rem;
}
.filter-scroll-row::-webkit-scrollbar { display: none; }
.filter-pill {
    white-space: nowrap; padding: 0 1.25rem; border-radius: 99px; background: var(--bg-card-2);
    border: 1px solid var(--border); color: var(--text-secondary); font-size: 0.85rem; font-weight: 600;
    display: inline-flex; align-items: center; justify-content: center; scroll-snap-align: start; flex-shrink: 0;
    height: 36px; min-height: 36px; transition: 0.2s;
}
.filter-pill:hover { border-color: rgba(255,255,255,0.2); color: var(--text-primary); }
.filter-pill.active { background: var(--text-primary); color: var(--bg-base); border-color: transparent; }

/* ── Buttons ── */
.btn-primary, .btn-secondary, .btn-danger {
    display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem;
    padding: 0 1.5rem; border-radius: var(--radius-md); font-weight: 700; font-size: 0.95rem; text-align: center;
    height: var(--tap-target); min-height: var(--tap-target);
}
.btn-primary { background: var(--text-primary); color: var(--bg-base); transition: 0.2s; }
.btn-primary:hover { background: var(--text-primary); filter: brightness(0.85); box-shadow: 0 4px 15px rgba(255,255,255,0.1); }
.btn-secondary { background: var(--bg-card-2); border: 1px solid var(--border); color: var(--text-primary); transition: 0.2s; }
.btn-secondary:hover { background: rgba(255,255,255,0.08); border-color: rgba(255,255,255,0.2); }
.btn-danger { background: var(--ruby-dim); color: var(--ruby); border: 1px solid rgba(239,68,68,0.3); }
.btn-danger:hover { background: rgba(239,68,68,0.25); }
.btn-primary:active, .btn-secondary:active, .btn-danger:active { transform: scale(0.97); }
.fab-btn {
    width: 100%; box-shadow: 0 10px 25px rgba(0,0,0,0.5); border: 1px solid var(--border-focus); background: var(--indigo-dim); color: var(--indigo-light);
}
.fab-btn:hover { background: rgba(99,102,241,0.25); box-shadow: 0 12px 30px rgba(99,102,241,0.2); }

/* ── Glass Cards ── */
.glass-card { 
    background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); 
    padding: 1.25rem; overflow: hidden; position: relative; backdrop-filter: blur(12px);
    transition: border-color 0.2s, box-shadow 0.2s, transform 0.2s;
}
.glass-card:hover { border-color: rgba(255,255,255,0.14); box-shadow: 0 8px 24px rgba(0,0,0,0.4); }

/* ── Subject Tags ── */
.subj-tag { font-size: 0.7rem; font-weight: 700; padding: 0.2rem 0.6rem; border-radius: 99px; text-transform: uppercase; letter-spacing: 0.05em; display: inline-block; white-space: nowrap;}
.subj-tag.stats { background: rgba(14,165,233,0.15); color: var(--subj-stats); border: 1px solid rgba(14,165,233,0.3); }
.subj-tag.acct { background: rgba(236,72,153,0.15); color: var(--subj-acct); border: 1px solid rgba(236,72,153,0.3); }
.subj-tag.mgmt { background: rgba(139,92,246,0.15); color: var(--subj-mgmt); border: 1px solid rgba(139,92,246,0.3); }
.subj-tag.econ { background: rgba(6,182,212,0.15); color: var(--subj-econ); border: 1px solid rgba(6,182,212,0.3); }
.subj-tag.gen { background: rgba(148,163,184,0.15); color: var(--subj-gen); border: 1px solid rgba(148,163,184,0.3); }

/* ── Clean Minimal Borders ── */
.border-stats { border: 1px solid var(--border) !important; }
.border-acct { border: 1px solid var(--border) !important; }
.border-mgmt { border: 1px solid var(--border) !important; }
.border-econ { border: 1px solid var(--border) !important; }
.border-gen { border: 1px solid var(--border) !important; }

/* ── Tags & Chips ── */
.chip { display: inline-flex; align-items: center; gap: 0.3rem; background: var(--bg-card-2); border: 1px solid var(--border); font-size: 0.75rem; padding: 0.15rem 0.5rem; border-radius: 4px; color: var(--text-secondary); }

/* ── Difficulty Stars (Large & Tappable) ── */
.diff-stars { display: inline-flex; gap: 0.4rem; align-items: center; }
.diff-star { font-size: 1.5rem; color: var(--text-tertiary); cursor: pointer; transition: 0.2s; padding: 0.25rem; display: flex; align-items: center; justify-content: center; min-height: var(--tap-target); min-width: var(--tap-target); }
.diff-stars[data-val="1"] .star-1 { color: var(--diff-1); text-shadow: 0 0 10px rgba(16,185,129,0.4); }
.diff-stars[data-val="2"] .star-1, .diff-stars[data-val="2"] .star-2 { color: var(--diff-2); text-shadow: 0 0 10px rgba(132,204,22,0.4); }
.diff-stars[data-val="3"] .star-1, .diff-stars[data-val="3"] .star-2, .diff-stars[data-val="3"] .star-3 { color: var(--diff-3); text-shadow: 0 0 10px rgba(245,158,11,0.4); }
.diff-stars[data-val="4"] .star-1, .diff-stars[data-val="4"] .star-2, .diff-stars[data-val="4"] .star-3, .diff-stars[data-val="4"] .star-4 { color: var(--diff-4); text-shadow: 0 0 10px rgba(249,115,22,0.4); }
.diff-stars[data-val="5"] .star-1, .diff-stars[data-val="5"] .star-2, .diff-stars[data-val="5"] .star-3, .diff-stars[data-val="5"] .star-4, .diff-stars[data-val="5"] .star-5 { color: var(--diff-5); text-shadow: 0 0 10px rgba(239,68,68,0.4); }
.diff-star-mini { font-size: 0.9rem; margin-right: 0.2rem; }

/* ── Color Label System ── */
.label-chip { font-size: 0.7rem; font-weight: 700; padding: 0.15rem 0.5rem; border-radius: 4px; display: inline-flex; align-items: center; gap: 0.3rem; border: 1px solid; white-space: nowrap;}
.label-chip.super-important { color: var(--label-red); background: rgba(239,68,68,0.1); border-color: rgba(239,68,68,0.3); }
.label-chip.review-needed { color: var(--label-orange); background: rgba(249,115,22,0.1); border-color: rgba(249,115,22,0.3); }
.label-chip.done { color: var(--label-green); background: rgba(16,185,129,0.1); border-color: rgba(16,185,129,0.3); }
.label-chip.skip { color: var(--label-gray); background: rgba(100,116,139,0.1); border-color: rgba(100,116,139,0.3); text-decoration: line-through; }
.label-chip.exam-fav { color: var(--label-gold); background: rgba(234,179,8,0.1); border-color: rgba(234,179,8,0.3); }
.label-chip.confusing { color: var(--label-purple); background: rgba(217,70,239,0.1); border-color: rgba(217,70,239,0.3); }

/* ── Bookmark Toggle ── */
.bookmark-btn { font-size: 1.25rem; color: var(--text-tertiary); display: flex; align-items: center; justify-content: center; width: 48px; height: 48px; }
.bookmark-btn.active { color: var(--label-gold); text-shadow: 0 0 10px rgba(234,179,8,0.4); }

/* ── Annotations (Sticky notes) ── */
.annotation-box { background: rgba(234, 179, 8, 0.15); border-left: 3px solid var(--label-gold); padding: 0.75rem; border-radius: 0 4px 4px 0; margin-top: 1rem; font-size: 0.85rem; font-style: italic; position: relative;}
.annotation-box .edit-ann { position: absolute; right: 0.5rem; top: 0.5rem; color: var(--label-gold); font-size: 0.9rem; padding: 0.2rem; min-height: unset;}

/* ── Bottom Sheet ── */
.bottom-sheet {
    transform: translateY(110%);
    transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}
.full-modal-overlay.active .bottom-sheet {
    transform: translateY(0);
}

/* ── Full Screen Modals / Overlays (Mobile First) ── */
.full-modal-overlay {
    position: fixed; inset: 0; background: var(--bg-overlay); backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
    z-index: 4000; display: flex; flex-direction: column; opacity: 0; pointer-events: none; transition: opacity 0.3s ease;
}
.full-modal-overlay.active { opacity: 1; pointer-events: all; }
.full-modal-content {
    background: var(--bg-modal); flex: 1; display: flex; flex-direction: column; overflow: hidden;
}
.fm-header { padding: 1rem 1.25rem; border-bottom: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; background: var(--bg-surface); flex-shrink: 0; }
.fm-header h3 { font-family: var(--font-display); font-size: 1.2rem; }
.fm-close { font-size: 1.5rem; color: var(--text-secondary); width: 48px; height: 48px; display: flex; align-items: center; justify-content: center; margin-right: -10px; border-radius: var(--radius-sm); transition: 0.2s;}
.fm-close:hover { background: rgba(255,255,255,0.06); color: var(--text-primary); }
.fm-body { flex: 1; overflow-y: auto; padding: 1.5rem 1.25rem; -webkit-overflow-scrolling: touch; }
.fm-footer { padding: 1rem 1.25rem; border-top: 1px solid var(--border); background: var(--bg-surface); padding-bottom: calc(1rem + env(safe-area-inset-bottom)); flex-shrink: 0; }

/* ── PDF Viewer ── */
.pdf-viewer-container { width: 100%; height: 100%; border: none; background: #fff; }

/* ── Toasts ── */
.toast-container { position: fixed; bottom: calc(var(--bottom-nav-ht) + 1rem); left: 50%; transform: translateX(-50%); z-index: 9999; display: flex; flex-direction: column; gap: 0.5rem; width: 90%; max-width: 400px; pointer-events: none; }
@media (min-width: 1024px) { .toast-container { bottom: 2rem; right: 2rem; left: auto; transform: none; } }
.toast { background: var(--bg-card-2); border: 1px solid var(--border); padding: 1rem 1.25rem; border-radius: var(--radius-md); display: flex; align-items: center; gap: 0.875rem; box-shadow: 0 8px 24px rgba(0,0,0,0.6); pointer-events: all; }
.toast-success i { color: var(--emerald); }
.toast-error i { color: var(--ruby); }
.toast-info i { color: var(--indigo-light); }
.toast span { font-weight: 600; font-size: 0.9rem; }

/* ── Stepper ── */
.stepper-row { display: flex; align-items: center; justify-content: space-between; background: var(--bg-card-2); border: 1px solid var(--border); border-radius: var(--radius-md); padding: 0.5rem 0.5rem 0.5rem 1rem; margin-bottom: 1rem;}
.stepper-btn { width: 44px; height: 44px; background: var(--bg-card); border-radius: var(--radius-sm); font-size: 1.1rem; display: flex; align-items: center; justify-content: center; transition: 0.2s; border: 1px solid transparent;}
.stepper-btn:hover { border-color: var(--border-focus); color: var(--indigo-light); }
.stepper-btn:active { transform: scale(0.9); }
.stepper-val { font-family: var(--font-mono); font-size: 1.25rem; font-weight: 700; width: 50px; text-align: center; }

/* ── Color Label Buttons ── */
.color-lbl-btn { min-height: auto !important; flex-shrink: 0; border: 2px solid transparent; transition: transform 0.15s, box-shadow 0.15s; }
.color-lbl-btn.active { transform: scale(1.25); box-shadow: 0 0 0 3px rgba(255,255,255,0.4); }

/* ── Type Selector Grid ── */
.type-selector-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 0.75rem; margin-bottom: 1.5rem; }
.type-btn { background: var(--bg-card-2); border: 1px solid var(--border); border-radius: var(--radius-md); padding: 1rem; display: flex; flex-direction: column; align-items: center; gap: 0.5rem; color: var(--text-secondary); font-weight: 600; font-size: 0.85rem; min-height: auto; transition: all 0.2s; }
.type-btn i { font-size: 1.5rem; }
.type-btn.active { background: var(--indigo-dim); border-color: var(--border-focus); color: var(--indigo-light); box-shadow: inset 0 0 10px rgba(99,102,241,0.2); }
.type-btn:hover:not(.active) { background: rgba(255,255,255,0.05); color: var(--text-primary); }

/* ── Desktop: Modal Adjustments (1024px+) ── */
@media (min-width: 1024px) {
    /* Desktop: Modals become centered dialogs, not full-screen */
    .full-modal-overlay {
        align-items: center;
        justify-content: center;
        padding: 2rem;
    }
    .full-modal-content {
        flex: 0 0 auto;
        width: 100%;
        max-width: 580px;
        max-height: 88vh;
        border-radius: var(--radius-lg);
        box-shadow: 0 32px 80px rgba(0,0,0,0.85), 0 0 0 1px var(--border);
    }
    /* Wider viewer modal */
    #modalViewer .full-modal-content { max-width: 960px; max-height: 90vh; }
    /* JSON upload modal - slightly narrower */
    #modalJsonUpload .full-modal-content { max-width: 520px; }
    
    /* Desktop: Bottom sheets become centered scale-in modals */
    #mobileMoreMenu, #modalAnnotation {
        justify-content: center;
        align-items: center;
    }
    .bottom-sheet {
        width: 100%;
        max-width: 420px;
        border-radius: var(--radius-lg) !important;
        transform: scale(0.96) translateY(0) !important;
        opacity: 0;
        transition: opacity 0.2s ease, transform 0.2s ease !important;
    }
    .full-modal-overlay.active .bottom-sheet {
        transform: scale(1) translateY(0) !important;
        opacity: 1;
    }
}

/* ── Tablet: Type Selector (768px+) ── */
@media (min-width: 768px) {
    .type-selector-grid { grid-template-columns: repeat(4, 1fr); }
}

/* ── AI Flashcard Flip Animation ── */
.flashcard-container {
    user-select: none;
    -webkit-tap-highlight-color: transparent;
}
.flashcard-container.flipped .flashcard-inner {
    transform: rotateY(180deg);
}
.flashcard-front, .flashcard-back {
    box-shadow: 0 8px 24px -8px rgba(0,0,0,0.2);
}
.flashcard-container:hover .flashcard-front {
    border-color: rgba(168, 85, 247, 0.8) !important;
}
.flashcard-container:hover .flashcard-back {
    border-color: rgba(16, 185, 129, 0.8) !important;
}