@layer reset, tokens, base, components, utilities;

/* ------------------------------------------------------------------ */
/*  RESET                                                              */
/* ------------------------------------------------------------------ */
@layer reset {
    *,
    *::before,
    *::after {
        box-sizing: border-box;
        margin: 0;
        padding: 0;
    }

    img,
    svg {
        display: block;
        max-inline-size: 100%;
    }

    button,
    input,
    select,
    textarea {
        font-family: inherit;
        font-size: inherit;
        color: inherit;
    }
}

/* ------------------------------------------------------------------ */
/*  TOKENS                                                             */
/* ------------------------------------------------------------------ */
@layer tokens {
    :root {
        /* ---- palette ---- */
        --brand-primary: #58a6ff;
        --brand-primary-hover: #79b8ff;
        --brand-success: #2ea043;
        --brand-danger: #ff5555;
        --brand-purple: #8957e5;
        --bg-body: #0d1117;
        --bg-card: rgba(22, 27, 34, 0.6);
        --text-primary: #c9d1d9;
        --text-heading: #ffffff;
        --text-muted: #8b949e;
        --border-subtle: rgba(255, 255, 255, 0.1);
        --border-input: #30363d;

        /* ---- spacing ---- */
        --space-xs: 0.25rem;
        --space-sm: 0.5rem;
        --space-md: 1rem;
        --space-lg: 1.5rem;
        --space-xl: 2rem;
        --space-2xl: 3rem;
        --space-3xl: 4rem;

        /* ---- radius ---- */
        --radius-sm: 6px;
        --radius-md: 8px;
        --radius-lg: 12px;
        --radius-xl: 16px;
        --radius-full: 50%;

        /* ---- typography ---- */
        --font-family: 'Outfit', sans-serif;
        --font-size-sm: clamp(0.75rem, 1vw, 0.875rem);
        --font-size-base: clamp(0.95rem, 1.2vw, 1.05rem);
        --font-size-lg: clamp(1.1rem, 1.5vw, 1.25rem);
        --font-size-xl: clamp(1.3rem, 2vw, 1.8rem);
        --font-size-2xl: clamp(2rem, 5vw, 3rem);

        /* ---- transitions ---- */
        --transition-base: 200ms ease;
        --transition-slow: 400ms ease;

        /* ---- shadows ---- */
        --shadow-card: 0 10px 30px rgba(0, 0, 0, 0.3);
        --shadow-button: 0 4px 12px rgba(88, 166, 255, 0.3);
    }

    @media (prefers-color-scheme: light) {
        :root {
            --brand-primary: #0969da;
            --brand-primary-hover: #0550b3;
            --brand-success: #1a7f37;
            --brand-danger: #cf222e;
            --brand-purple: #8250df;
            --bg-body: #f6f8fa;
            --bg-card: rgba(255, 255, 255, 0.7);
            --text-primary: #24292f;
            --text-heading: #1f2328;
            --text-muted: #656d76;
            --border-subtle: rgba(0, 0, 0, 0.08);
            --border-input: #d0d7de;
            --shadow-card: 0 8px 24px rgba(0, 0, 0, 0.08);
            --shadow-button: 0 2px 8px rgba(9, 105, 218, 0.2);
        }
    }
}

/* ------------------------------------------------------------------ */
/*  BASE                                                               */
/* ------------------------------------------------------------------ */
@layer base {
    html {
        color-scheme: dark light;
    }

    body {
        font-family: var(--font-family);
        background-color: var(--bg-body);
        color: var(--text-primary);
        min-block-size: 100dvb;
        overflow-x: hidden;
        position: relative;
    }

    /* focus-visible for keyboard navigation */
    :focus-visible {
        outline: 2px solid var(--brand-primary);
        outline-offset: 2px;
        border-radius: var(--radius-sm);
    }

    /* reduced-motion: strip all animations */
    @media (prefers-reduced-motion: reduce) {
        *,
        *::before,
        *::after {
            animation-duration: 0.01ms !important;
            animation-iteration-count: 1 !important;
            transition-duration: 0.01ms !important;
            scroll-behavior: auto !important;
        }
    }

    /* --- background blobs --- */
    .background-blobs {
        position: fixed;
        inset: 0;
        z-index: -1;
        overflow: hidden;
        pointer-events: none;
    }

    .blob {
        position: absolute;
        filter: blur(80px);
        border-radius: var(--radius-full);
        opacity: 0.4;
    }

    @media (prefers-reduced-motion: no-preference) {
        .blob {
            animation: float 20s infinite ease-in-out;
        }
    }

    .blob-1 {
        inset-block-start: -10%;
        inset-inline-start: -10%;
        inline-size: clamp(200px, 30dvw, 400px);
        block-size: clamp(200px, 30dvw, 400px);
        background: var(--brand-primary);
    }

    .blob-2 {
        inset-block-end: -10%;
        inset-inline-end: -10%;
        inline-size: clamp(250px, 35dvw, 500px);
        block-size: clamp(250px, 35dvw, 500px);
        background: var(--brand-purple);
        animation-delay: -5s;
    }

    .blob-3 {
        inset-block-start: 40%;
        inset-inline-start: 50%;
        inline-size: clamp(150px, 25dvw, 300px);
        block-size: clamp(150px, 25dvw, 300px);
        background: var(--brand-success);
        animation-delay: -10s;
    }

    @keyframes float {
        0%, 100% { transform: translate(0, 0) scale(1); }
        33% { transform: translate(30px, -50px) scale(1.1); }
        66% { transform: translate(-20px, 20px) scale(0.9); }
    }

    /* --- layout shell --- */
    .container {
        inline-size: min(92%, 1200px);
        margin-inline: auto;
        padding-block: clamp(2rem, 4vw, 3rem);
        padding-inline: clamp(1rem, 2vw, 2rem);
    }

    header {
        text-align: center;
        margin-block-end: var(--space-3xl);
    }

    h1 {
        color: var(--text-heading);
        font-size: var(--font-size-2xl);
        font-weight: 600;
        margin-block-end: var(--space-sm);
        letter-spacing: -0.5px;
    }

    header p {
        font-size: var(--font-size-lg);
        opacity: 0.8;
    }

    /* --- footer --- */
    footer {
        text-align: center;
        padding: var(--space-xl);
        margin-block-start: var(--space-xl);
        border-block-start: 1px solid var(--border-subtle);
    }

    .footer-link {
        background: none;
        border: none;
        color: var(--text-primary);
        font-size: var(--font-size-sm);
        opacity: 0.6;
        cursor: pointer;
        text-decoration: underline;
        font-family: inherit;
        transition: opacity var(--transition-base);
    }

    .footer-link:hover {
        opacity: 1;
    }
}

/* ------------------------------------------------------------------ */
/*  COMPONENTS                                                         */
/* ------------------------------------------------------------------ */
@layer components {

    /* ---- header controls row ---- */
    .header-controls {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: var(--space-md);
        align-items: center;
        margin-block-start: var(--space-md);
    }

    /* ---- buttons ---- */
    .btn-primary {
        display: inline-block;
        padding-block: 0.8rem;
        padding-inline: 1.5rem;
        background-color: transparent;
        border: 2px solid var(--brand-primary);
        border-radius: var(--radius-md);
        color: var(--brand-primary);
        text-decoration: none;
        font-weight: 600;
        font-size: var(--font-size-base);
        cursor: pointer;
        transition: background-color var(--transition-base),
                    color var(--transition-base),
                    transform var(--transition-base),
                    box-shadow var(--transition-base);
    }

    @media (prefers-reduced-motion: no-preference) {
        .btn-primary:hover {
            background-color: var(--brand-primary);
            color: var(--bg-body);
            transform: translateY(-2px);
            box-shadow: var(--shadow-button);
        }
    }

    @media (prefers-reduced-motion: reduce) {
        .btn-primary:hover {
            background-color: var(--brand-primary);
            color: var(--bg-body);
        }
    }

    .btn-primary:active {
        transform: translateY(0);
    }

    /* ---- sort select ---- */
    .sort-select {
        display: inline-block;
        padding-block: 0.7rem;
        padding-inline: 1rem;
        background-color: var(--bg-card);
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-md);
        color: var(--text-primary);
        font-size: var(--font-size-base);
        cursor: pointer;
        transition: border-color var(--transition-base);
    }

    .sort-select:hover {
        border-color: var(--brand-primary);
    }

    /* ---- category section ---- */
    .category-section {
        margin-block-end: var(--space-2xl);
        content-visibility: auto;
        contain-intrinsic-block-size: 300px;
    }

    .category-title {
        color: var(--text-heading);
        font-size: var(--font-size-xl);
        font-weight: 600;
        margin-block-end: var(--space-lg);
        padding-block-end: var(--space-sm);
        border-block-end: 1px solid var(--border-subtle);
    }

    /* ---- bookmarks grid with container query ---- */
    .bookmarks-grid {
        container-type: inline-size;
        container-name: grid;
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
        gap: var(--space-lg);
    }

    @container grid (inline-size < 400px) {
        .bookmarks-grid {
            grid-template-columns: 1fr;
        }
    }

    /* ---- bookmark card ---- */
    .bookmark-card {
        position: relative;
        display: flex;
        flex-direction: column;
        justify-content: space-between;
        background: var(--bg-card);
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-xl);
        padding: var(--space-lg);
        min-block-size: 120px;
        aspect-ratio: auto;
        text-decoration: none;
        cursor: pointer;
        overflow: hidden;
        transition: transform var(--transition-base),
                    border-color var(--transition-base),
                    box-shadow var(--transition-base),
                    opacity var(--transition-base);
        backdrop-filter: blur(16px);
        -webkit-backdrop-filter: blur(16px);
    }

    .bookmark-card--dragging {
        opacity: 0.5;
        border-style: dashed;
    }

    .bookmarks-grid--drop-target {
        outline: 2px dashed var(--brand-primary);
        outline-offset: 4px;
        border-radius: var(--radius-xl);
        background: rgba(88, 166, 255, 0.05);
    }

    /* ---- move dropdown ---- */
    .move-dropdown {
        position: absolute;
        inset-inline-end: 0;
        inset-block-start: calc(100% + 4px);
        z-index: 50;
        min-inline-size: 160px;
        max-block-size: 220px;
        overflow-y: auto;
        background: var(--bg-body);
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-md);
        box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
        padding: var(--space-xs);
    }

    .move-dropdown__item {
        display: block;
        inline-size: 100%;
        padding: var(--space-sm) var(--space-md);
        background: none;
        border: none;
        border-radius: var(--radius-sm);
        color: var(--text-primary);
        font-size: var(--font-size-sm);
        text-align: start;
        cursor: pointer;
        transition: background-color var(--transition-base);
    }

    .move-dropdown__item:hover {
        background: var(--brand-primary);
        color: var(--bg-body);
    }

    .move-dropdown__empty {
        display: block;
        padding: var(--space-sm) var(--space-md);
        color: var(--text-muted);
        font-size: var(--font-size-sm);
    }

    @media (prefers-reduced-motion: no-preference) {
        .bookmark-card:hover {
            transform: translateY(-5px);
            border-color: var(--brand-primary);
            box-shadow: var(--shadow-card);
        }
    }

    @media (prefers-reduced-motion: reduce) {
        .bookmark-card:hover {
            border-color: var(--brand-primary);
            box-shadow: var(--shadow-card);
        }
    }

    /* shimmer overlay */
    .bookmark-card::before {
        content: '';
        position: absolute;
        inset: 0;
        background: linear-gradient(45deg, transparent, rgba(255, 255, 255, 0.05), transparent);
        transform: translateX(-100%);
        transition: transform 0.6s ease;
        pointer-events: none;
    }

    @media (prefers-reduced-motion: no-preference) {
        .bookmark-card:hover::before {
            transform: translateX(100%);
        }
    }

    .bookmark-title {
        color: var(--text-heading);
        font-size: var(--font-size-lg);
        font-weight: 600;
        margin-block-end: var(--space-sm);
        display: -webkit-box;
        -webkit-line-clamp: 2;
        -webkit-box-orient: vertical;
        overflow: hidden;
    }

    .bookmark-url {
        color: var(--brand-primary);
        font-size: var(--font-size-sm);
        opacity: 0.8;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
    }

    /* ---- card action buttons ---- */
    .delete-btn {
        position: absolute;
        inset-block-start: var(--space-md);
        border: none;
        border-radius: var(--radius-full);
        inline-size: 30px;
        block-size: 30px;
        display: flex;
        align-items: center;
        justify-content: center;
        cursor: pointer;
        opacity: 0;
        transition: opacity var(--transition-base),
                    background-color var(--transition-base);
        z-index: 10;
    }

    .delete-btn--danger {
        inset-inline-end: var(--space-md);
        background: rgba(255, 0, 0, 0.2);
        color: var(--brand-danger);
    }

    .delete-btn--danger:hover {
        background: rgba(255, 0, 0, 0.5);
        color: #fff;
    }

    .delete-btn--move {
        inset-inline-end: 3.5rem;
        background: rgba(255, 255, 255, 0.1);
        color: var(--text-primary);
    }

    .delete-btn--move:hover {
        background: rgba(255, 255, 255, 0.25);
    }

    .bookmark-card:hover .delete-btn {
        opacity: 1;
    }

    /* ---- modal ---- */
    .modal {
        display: none;
        position: fixed;
        z-index: 100;
        inset: 0;
        overflow: auto;
        background-color: rgba(0, 0, 0, 0.7);
        backdrop-filter: blur(5px);
        align-items: center;
        justify-content: center;
    }

    .modal-content {
        background-color: var(--bg-body);
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-lg);
        padding: var(--space-xl);
        inline-size: 90%;
        max-inline-size: 600px;
        position: relative;
        box-shadow: 0 15px 35px rgba(0, 0, 0, 0.5);
    }

    .modal-content h2 {
        margin-block-start: 0;
        margin-block-end: var(--space-md);
        color: var(--text-heading);
    }

    .modal-content ol {
        margin-block-start: var(--space-lg);
        margin-inline-start: var(--space-lg);
        line-height: 1.6;
    }

    .modal-content li {
        margin-block-end: var(--space-md);
    }

    .close-modal {
        color: var(--text-primary);
        float: inline-end;
        font-size: 28px;
        font-weight: bold;
        cursor: pointer;
        line-height: 1;
        transition: color var(--transition-base);
    }

    .close-modal:hover {
        color: var(--text-heading);
    }

    /* ---- category management (modal list) ---- */
    .category-list-item {
        display: flex;
        justify-content: space-between;
        align-items: center;
        margin-block-end: var(--space-sm);
        padding: var(--space-sm);
        background: var(--bg-card);
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-md);
    }

    .category-list-item__actions {
        display: flex;
        gap: var(--space-xs);
        align-items: center;
    }

    .category-list-item__btn {
        cursor: pointer;
        background: none;
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-sm);
        padding: 2px 6px;
        color: var(--text-primary);
        font-size: var(--font-size-sm);
        transition: background-color var(--transition-base);
    }

    .category-list-item__btn:hover {
        background: var(--brand-primary);
        color: var(--bg-body);
    }

    .category-list-item__btn--danger {
        color: var(--brand-danger);
    }

    .category-list-item__btn--danger:hover {
        background: var(--brand-danger);
        color: #fff;
    }

    /* ---- modal add-category row ---- */
    .category-add-row {
        display: flex;
        gap: var(--space-sm);
        margin-block-start: var(--space-md);
    }

    .category-add-row .btn-primary {
        margin-block-start: 0;
        padding-block: 0.5rem;
        padding-inline: 1rem;
    }

    /* ---- text input ---- */
    .input-field {
        flex: 1;
        padding: var(--space-sm);
        border-radius: var(--radius-sm);
        border: 1px solid var(--border-subtle);
        background: var(--bg-card);
        color: var(--text-heading);
    }

    .input-field::placeholder {
        color: var(--text-muted);
    }

    .input-field:focus-visible {
        border-color: var(--brand-primary);
        outline: none;
    }

    /* ---- modal category list ---- */
    .modal-category-list {
        margin-block-start: var(--space-lg);
        max-block-size: 300px;
        overflow-y: auto;
    }

    /* ---- loading state ---- */
    .loading {
        text-align: center;
        font-size: var(--font-size-lg);
        color: var(--brand-primary);
        margin-block-start: 5rem;
    }

    @media (prefers-reduced-motion: no-preference) {
        .loading {
            animation: pulse 1.5s infinite;
        }
    }

    @keyframes pulse {
        0%, 100% { opacity: 1; }
        50% { opacity: 0.5; }
    }

    /* ---- empty state ---- */
    .empty-state {
        text-align: center;
        opacity: 0.7;
    }
}

/* ------------------------------------------------------------------ */
/*  UTILITIES                                                          */
/* ------------------------------------------------------------------ */
@layer utilities {
    .sr-only {
        position: absolute;
        inline-size: 1px;
        block-size: 1px;
        margin: -1px;
        padding: 0;
        border: 0;
        overflow: hidden;
        clip: rect(0, 0, 0, 0);
        white-space: nowrap;
    }
}