:root {
    --bg-color: #0f172a;
    --panel-bg: rgba(30, 41, 59, 0.7);
    --panel-border: rgba(255, 255, 255, 0.1);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --hover-bg: rgba(255, 255, 255, 0.05);
    
    --cal-highlight: rgba(59, 130, 246, 0.2);
    --cal-highlight-border: #3b82f6;
    
    --pill-outbound: #ffd8b1;
    --pill-inbound: #dcbeff;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    background-image: radial-gradient(circle at top right, #1e1b4b, transparent 40%),
                      radial-gradient(circle at bottom left, #0f172a, transparent 40%);
    background-attachment: fixed;
    color: var(--text-primary);
    min-height: 100vh;
    padding: 20px;
}

.app-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 20px;
    height: calc(100vh - 40px);
}

.glass-panel {
    background: var(--panel-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--panel-border);
    border-radius: 16px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.top-bar {
    padding: 15px 20px;
    display: flex;
    flex-direction: column;
    gap: 10px;
    position: relative;
}

.last-run-info {
    position: absolute;
    bottom: 15px;
    right: 20px;
    font-size: 0.75rem;
    color: var(--text-secondary);
}

h1 {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.02em;
    display: none; /* Hidden visually to save space but keep semantics if needed */
}

.filters {
    display: grid;
    grid-template-columns: auto auto;
    gap: 15px 40px;
    align-items: start;
    justify-content: start;
}
.filter-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.filter-group label {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.button-group {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.filter-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--panel-border);
    color: var(--text-primary);
    padding: 6px 12px;
    border-radius: 8px;
    cursor: pointer;
    font-family: inherit;
    font-size: 0.9rem;
    transition: all 0.2s ease;
}

.filter-btn:hover {
    background: rgba(255, 255, 255, 0.15);
}

.filter-btn.active {
    background: var(--accent-color);
    border-color: var(--accent-color);
    color: white;
}

.slider-group input[type="range"] {
    width: 200px;
    cursor: pointer;
    accent-color: var(--accent-color);
}

.price-input {
    background: transparent;
    border: 1px solid var(--panel-border);
    color: var(--text-primary);
    border-radius: 6px;
    padding: 6px 10px;
    width: 90px;
    font-family: inherit;
    font-size: 1rem;
    margin-left: 5px;
    text-align: left;
    transition: all 0.2s ease;
}

.price-input:hover {
    background: rgba(255, 255, 255, 0.05);
}

.price-input:focus {
    outline: none;
    border-color: var(--accent-color);
    background: rgba(255, 255, 255, 0.1);
}

.price-input::-webkit-inner-spin-button,
.price-input::-webkit-outer-spin-button {
    margin-left: 10px;
    height: 100%;
    cursor: pointer;
}

.content-area {
    display: flex;
    gap: 20px;
    flex: 1;
    min-height: 0;
}

.calendar-panel {
    flex: 2;
    display: flex;
    flex-direction: column;
    padding: 24px;
    overflow-y: auto;
}

.calendar-header {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 15px;
    margin-bottom: 20px;
    position: relative;
}

.calendar-header h2 {
    font-size: 1.25rem;
    font-weight: 600;
}

.icon-button {
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 1.5rem;
    cursor: pointer;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s;
}

.icon-button:hover {
    background: var(--hover-bg);
}

.calendar-grid-header {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    text-align: center;
    margin-bottom: 10px;
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.calendar-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    grid-auto-rows: minmax(80px, 1fr);
    gap: 8px;
    flex: 1;
    position: relative;
}

.cal-day {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--panel-border);
    border-radius: 12px;
    padding: 10px;
    display: flex;
    flex-direction: column;
    position: relative;
    transition: all 0.3s ease;
    min-height: 80px;
}

.cal-day.empty {
    background: transparent;
    border-color: transparent;
}

.cal-day.other-month {
    background: rgba(0, 0, 0, 0.2);
    color: var(--text-secondary);
}

.day-number {
    font-size: 1.1rem;
    font-weight: 500;
    z-index: 1;
}

.cal-day:not(.empty):hover {
    background-color: var(--cal-bg-hover);
    border-color: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.3);
}

.cal-day.selected {
    border: 2px solid white;
    z-index: 3;
}

.cal-day.highlight {
    background: var(--cal-highlight);
    border-color: var(--cal-highlight-border);
    transform: scale(1.02);
    box-shadow: 0 0 15px rgba(59, 130, 246, 0.3);
}

.pill {
    position: absolute;
    font-size: 0.7rem;
    font-weight: 700;
    padding: 3px 6px;
    border-radius: 12px;
    color: #1e293b;
    z-index: 2;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
    animation: popIn 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275) forwards;
}

@keyframes popIn {
    0% { transform: scale(0.5); opacity: 0; }
    100% { transform: scale(1); opacity: 1; }
}

.pill.outbound {
    background-color: var(--pill-outbound);
    top: 6px;
    right: 45px;
}

.pill.inbound {
    background-color: var(--pill-inbound);
    top: 6px;
    right: 6px;
}

.flights-panel {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding: 24px;
    overflow: hidden;
}

.flights-header {
    margin-bottom: 20px;
}

.flights-header h2 {
    font-size: 1.25rem;
    font-weight: 600;
}

.flights-list {
    flex: 1;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
    padding-right: 10px;
    padding-left: 8px; /* Compensate for hover shift */
}

.flights-list::-webkit-scrollbar {
    width: 6px;
}
.flights-list::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 4px;
}
.flights-list::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
}
.flights-list::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.3);
}

.flight-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--panel-border);
    border-radius: 12px;
    padding: 16px;
    cursor: pointer;
    transition: all 0.2s ease;
    position: relative;
    overflow: hidden;
    flex-shrink: 0;
}

.new-ribbon {
    position: absolute;
    top: -4px;
    right: -4px;
    width: 60px;
    height: 60px;
    overflow: hidden;
    z-index: 10;
}

.new-ribbon span {
    position: absolute;
    display: block;
    width: 85px;
    padding: 4px 0;
    background-color: #009688;
    box-shadow: 0 2px 4px rgba(0,0,0,0.3);
    color: #fff;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    text-align: center;
    transform: rotate(45deg);
    top: 12px;
    right: -20px;
    letter-spacing: 1px;
}

.flight-card:hover {
    background: var(--hover-bg);
    transform: translateX(-4px);
    border-color: var(--accent-color);
}

.flight-price {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-color);
    margin-bottom: 8px;
}

.flight-route {
    font-size: 0.95rem;
    font-weight: 500;
    margin-bottom: 4px;
}

.flight-dates {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.trip-line-segment {
    position: absolute;
    height: 4px;
    border-radius: 2px;
    z-index: 10;
    pointer-events: none;
    opacity: 0.8;
    animation: fadeInLine 0.3s ease forwards;
}

@keyframes fadeInLine {
    from { opacity: 0; transform: scaleX(0); transform-origin: left; }
    to { opacity: 0.8; transform: scaleX(1); transform-origin: left; }
}

/* Mobile Responsive Adjustments */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }

    .app-container {
        height: auto;
        min-height: calc(100vh - 20px);
    }

    .top-bar {
        padding: 15px;
    }

    .filters {
        grid-template-columns: 1fr;
    }

    .content-area {
        flex-direction: column;
        overflow: visible;
    }

    .calendar-panel, .flights-panel {
        flex: none;
        overflow: visible;
    }

    .calendar-panel {
        min-height: 450px;
        padding: 15px;
    }

    .flights-panel {
        min-height: 400px;
        padding: 15px;
    }

    .cal-day {
        min-height: 60px;
        padding: 5px;
    }
    
    .pill {
        font-size: 0.6rem;
        padding: 2px 4px;
    }
    
    .pill.outbound {
        right: 30px;
    }

    #reset-date-btn {
        font-size: 0;
        width: 32px;
        height: 32px;
        padding: 0;
        min-width: unset;
        text-align: center;
        line-height: 30px;
    }

    #reset-date-btn::after {
        content: "✖";
        font-size: 14px;
    }
}