/**
 * PUMKIN.DEV Academic Design System - Layout Stylesheet
 * Layer: 2 - Layout (Navigation, App Shell, Views, Headers, Filters, Shell Grids, Exam Topbar)
 */

/* Top Navigation Bar */
.pumkin-nav-container {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--nav-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.03);
    margin: 0;
    padding: 0 20px;
    text-align: left;
}

.pumkin-nav {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    height: 64px;
    gap: 12px;
    padding: 0 16px;
}

.brand-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    font-weight: 800;
    font-size: 18px;
    color: var(--primary);
    letter-spacing: 0.5px;
    flex-shrink: 0;
    cursor: pointer;
}

.brand-badge {
    background: var(--color-accent-bg);
    color: var(--color-accent);
    border: 1px solid rgba(234, 88, 12, 0.25);
    font-size: 10.5px;
    font-weight: 700;
    padding: 2px 7px;
    border-radius: 6px;
    letter-spacing: 0.6px;
    text-transform: uppercase;
}

.nav-scroll-wrapper {
    display: flex;
    align-items: center;
    position: relative;
    flex: 1;
    min-width: 0;
    overflow: hidden;
}

.nav-scroll-arrow {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    border: 1px solid var(--border-color);
    background: var(--card-bg);
    color: var(--text-main);
    font-size: 18px;
    font-weight: 700;
    line-height: 1;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    z-index: 2;
    transition: all 0.2s ease;
    box-shadow: 0 2px 5px rgba(0,0,0,0.06);
}

.nav-scroll-arrow:hover {
    background: var(--primary);
    color: #ffffff;
    border-color: var(--primary);
}

.nav-scroll-prev { margin-right: 4px; }
.nav-scroll-next { margin-left: 4px; }

.nav-links {
    display: flex;
    gap: 6px;
    overflow-x: auto;
    overflow-y: hidden;
    scrollbar-width: thin;
    scrollbar-color: #cbd5e1 transparent;
    -webkit-overflow-scrolling: touch;
    scroll-behavior: smooth;
    padding: 4px 2px;
    flex: 1;
}

.nav-links::-webkit-scrollbar {
    height: 4px;
}

.nav-links::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 4px;
}

.nav-links::-webkit-scrollbar-track {
    background: transparent;
}

.nav-right-actions {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

.btn-theme-toggle {
    width: 44px;
    height: 44px;
    min-width: 44px;
    min-height: 44px;
    border-radius: 50%;
    border: 1px solid var(--border-color);
    background: var(--card-bg);
    color: var(--text-main);
    font-size: 17px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.btn-theme-toggle:hover {
    transform: scale(1.08);
    border-color: var(--primary-light);
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

.nav-tab {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    min-height: 44px;
    border-radius: 8px;
    font-size: 13.5px;
    font-weight: 600;
    color: var(--text-muted);
    background: transparent;
    border: none;
    cursor: pointer;
    white-space: nowrap;
    transition: all 0.2s ease;
}

.nav-tab:hover {
    color: var(--primary);
    background: var(--primary-bg);
}

.nav-tab.active {
    color: #ffffff !important;
    background: #0f172a !important;
    border-color: #0f172a;
    font-weight: 600;
    box-shadow: 0 1px 3px rgba(15, 23, 42, 0.2);
}
body.dark-mode .nav-tab.active {
    background: #232d3f !important;
    border-color: #334155;
    color: #f8fafc !important;
}

.nav-badge-count {
    background: #ef4444;
    color: white;
    font-size: 10px;
    padding: 1px 6px;
    border-radius: 10px;
    font-weight: 700;
}

/* Views Visibility Control */
.app-view {
    display: none;
}

.app-view.active {
    display: block;
    opacity: 1;
    animation: fadeIn 0.25s ease-in-out forwards;
}

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

/* Common Section Headers */
.view-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 25px;
    padding-bottom: 16px;
    border-bottom: 2px solid #e2e8f0;
}

.view-title-group h2 {
    margin: 0 0 6px 0;
    border-bottom: none;
    padding: 0;
    font-size: 22px;
}

.view-subtitle {
    font-size: 14px;
    color: var(--text-muted);
    margin: 0;
}

/* Filter & Search Bar */
.filter-panel {
    background: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 18px 20px;
    margin-bottom: 25px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.03);
}

.search-box-wrapper {
    position: relative;
    margin-bottom: 16px;
}

.search-input {
    width: 100%;
    padding: 12px 16px 12px 42px;
    border: 1.5px solid #cbd5e1;
    border-radius: 8px;
    font-size: 14.5px;
    transition: all 0.2s;
    font-family: inherit;
    background: #f8fafc;
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-light);
    background: #ffffff;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.search-icon {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 16px;
    color: #94a3b8;
}

.filter-row {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
}

.filter-group {
    display: flex;
    align-items: center;
    gap: 6px;
}

.filter-label {
    font-size: 13px;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.filter-select {
    padding: 7px 12px;
    border-radius: 6px;
    border: 1px solid #cbd5e1;
    background: white;
    font-size: 13.5px;
    font-family: inherit;
    color: var(--text-main);
    cursor: pointer;
    outline: none;
    transition: border-color 0.2s;
}

.filter-select:focus {
    border-color: var(--primary-light);
}

.filter-pills {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.filter-pill {
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 12.5px;
    font-weight: 600;
    cursor: pointer;
    background: #f1f5f9;
    color: var(--text-muted);
    border: 1px solid transparent;
    transition: all 0.2s;
}

.filter-pill:hover {
    background: #e2e8f0;
    color: var(--text-main);
}

.filter-pill.active {
    background: var(--primary);
    color: white;
    box-shadow: 0 2px 4px rgba(30, 58, 138, 0.2);
}

/* Exam Card Grid */
.exam-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 20px;
}

.exam-card {
    background: #ffffff;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 22px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transition: all 0.25s ease;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.03);
    position: relative;
    overflow: hidden;
}

.exam-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px -3px rgba(0, 0, 0, 0.08);
    border-color: #93c5fd;
}

.exam-card-badge-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.badge-tag {
    font-size: 11.5px;
    font-weight: 700;
    padding: 3px 9px;
    border-radius: 6px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.badge-tsa { background: #dbeafe; color: #1e40af; }
.badge-hsa { background: #fef3c7; color: #92400e; }
.badge-thpt { background: #e0e7ff; color: #3730a3; }
.badge-calc { background: #fae8ff; color: #86198f; }

.badge-difficulty {
    font-size: 11.5px;
    font-weight: 600;
    padding: 3px 8px;
    border-radius: 4px;
}

.diff-easy { background: var(--success-bg); color: var(--success); }
.diff-medium { background: var(--warning-bg); color: var(--warning); }
.diff-hard { background: var(--danger-bg); color: var(--danger); }
.diff-expert { background: #581c87; color: #f3e8ff; }

.exam-card-title {
    font-size: 17px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 8px;
    line-height: 1.35;
}

.exam-card-desc {
    font-size: 13.5px;
    color: var(--text-muted);
    margin-bottom: 16px;
    line-height: 1.5;
    flex-grow: 1;
}

.exam-card-meta {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
    background: #f8fafc;
    padding: 10px 14px;
    border-radius: 6px;
    margin-bottom: 18px;
    font-size: 12.5px;
    color: #475569;
}

.exam-meta-item {
    display: flex;
    align-items: center;
    gap: 6px;
}

.exam-card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 14px;
    border-top: 1px solid #f1f5f9;
}

.exam-source-tag {
    font-size: 11.5px;
    color: #64748b;
    font-style: italic;
    max-width: 60%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 9px 18px;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: all 0.2s;
    font-family: inherit;
    text-decoration: none;
}

.btn-primary {
    background: #0f172a;
    color: #ffffff;
    font-weight: 500;
    border: 1px solid #0f172a;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.08);
}

.btn-primary:hover {
    background: #1e293b;
    border-color: #1e293b;
    transform: translateY(-1px);
    box-shadow: 0 3px 8px rgba(0, 0, 0, 0.12);
}

body.dark-mode .btn-primary {
    background: #ea580c;
    border-color: #ea580c;
    color: #ffffff;
}

body.dark-mode .btn-primary:hover {
    background: #c2410c;
    border-color: #c2410c;
}

.btn-success {
    background: var(--success);
    color: white;
}

.btn-success:hover {
    background: #047857;
}

.btn-outline {
    background: transparent;
    border: 1.5px solid #cbd5e1;
    color: var(--text-main);
}

.btn-outline:hover {
    background: #f1f5f9;
    border-color: #94a3b8;
}

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

.btn-danger:hover {
    background: #b91c1c;
}

.btn-sm {
    padding: 5px 12px;
    font-size: 12.5px;
    border-radius: 6px;
}

.btn-lg {
    padding: 13px 26px;
    font-size: 15.5px;
}

/* ==========================================================================
   EXAM PLAYER (FOCUS MODE) - IMMERSIVE FULLSCREEN 80/20 LAYOUT
   ========================================================================== */
body.exam-mode-active .pumkin-nav-container,
body.exam-mode-active .pumkin-footer,
body.exam-mode-active footer {
    display: none !important;
}

body.exam-mode-active {
    overflow-x: hidden;
    background: #f1f5f9;
}

body.exam-mode-active .wrapper {
    margin: 0 !important;
    padding: 0 !important;
    max-width: 100vw !important;
    width: 100vw !important;
    box-sizing: border-box !important;
}

#view-exam-player {
    width: 100% !important;
    min-height: 100vh;
    padding: 0 !important;
    margin: 0 !important;
}

.exam-player-container {
    background: #f8fafc;
    border-radius: 0 !important;
    border: none !important;
    box-shadow: none !important;
    width: 100% !important;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.exam-player-topbar {
    background: #ffffff;
    padding: 12px 32px;
    border-bottom: 2px solid #e2e8f0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 999;
    border-radius: 0 !important;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.04);
    width: 100%;
    box-sizing: border-box;
}

.exam-info-group h3 {
    margin: 0;
    font-size: 18px;
    font-weight: 800;
    color: var(--primary, #1e3a8a);
    letter-spacing: -0.2px;
}

.exam-progress-text {
    font-size: 13px;
    color: var(--text-muted, #64748b);
    font-weight: 600;
}

.timer-box {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 20px;
    border-radius: 30px;
    font-size: 18px;
    font-weight: 800;
    font-family: 'Courier New', Courier, monospace;
    letter-spacing: 1.5px;
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

.timer-normal {
    background: #eff6ff;
    color: #1d4ed8;
    border: 1.5px solid #bfdbfe;
}

.timer-warning {
    background: #fffbeb;
    color: #b45309;
    border: 1.5px solid #fde68a;
    animation: pulseWarning 1.5s infinite;
}

.timer-critical {
    background: #fef2f2;
    color: #b91c1c;
    border: 1.5px solid #fca5a5;
    animation: pulseCritical 0.8s infinite;
}

@keyframes pulseWarning {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.02); }
}

@keyframes pulseCritical {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.04); background: #fee2e2; }
}