/* DD Tools - Violet Theme */

:root {
    /* Fialová paleta odvozená od hsl(287, 44%, 27%) */
    --purple-deepest:  hsl(287, 50%, 14%);
    --purple-dark:     hsl(287, 47%, 20%);
    --purple-main:     hsl(287, 44%, 27%);
    --purple-mid:      hsl(287, 42%, 40%);
    --purple-pale:     hsl(287, 28%, 96%);

    /* Neutrální plochy */
    --bg-light:        hsl(280, 18%, 97%);
    --bg-white:        #ffffff;
    --text-dark:       hsl(270, 15%, 15%);
    --text-light:      hsl(270, 8%, 46%);
    --border-color:    hsl(280, 18%, 89%);

    /* Stavy */
    --success:         #16a34a;
    --success-bg:      #dcfce7;
    --success-text:    #14532d;
    --error:           #dc2626;
    --error-bg:        #fee2e2;
    --error-text:      #7f1d1d;

    /* Stíny tónované do fialové */
    --shadow-sm:   0 1px 3px hsla(287, 44%, 27%, 0.08),
                   0 1px 2px hsla(287, 44%, 27%, 0.05);
    --shadow-md:   0 4px 14px hsla(287, 44%, 27%, 0.13),
                   0 2px 4px  hsla(287, 44%, 27%, 0.07);
    --shadow-lg:   0 8px 28px hsla(287, 44%, 27%, 0.18),
                   0 4px 8px  hsla(287, 44%, 27%, 0.09);
    --focus-ring:  0 0 0 3px  hsla(287, 44%, 27%, 0.22);

    /* Aliasy pro zpětnou kompatibilitu (dříve nedefinované — oprava) */
    --shadow-primary-sm:  var(--focus-ring);
    --shadow-primary-md:  var(--shadow-md);
    --shadow-primary-lg:  var(--shadow-lg);
    --overlay-white-sm:   rgba(255, 255, 255, 0.10);
    --color-white:        #ffffff;
}

/* ── Reset ──────────────────────────────────────────────────────────────── */

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto,
                 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-dark);
    background-color: var(--bg-light);
    line-height: 1.6;
}

/* ── Layout ─────────────────────────────────────────────────────────────── */

.container {
    display: flex;
    min-height: 100vh;
}

/* ── Sidebar ─────────────────────────────────────────────────────────────── */

.sidebar {
    width: 260px;
    background: linear-gradient(180deg,
        var(--purple-deepest) 0%,
        var(--purple-main)    100%);
    color: white;
    padding: 0;
    box-shadow: 2px 0 16px hsla(287, 44%, 10%, 0.30);
    flex-shrink: 0;
}

.sidebar-header {
    padding: 28px 20px 24px;
    border-bottom: 1px solid var(--overlay-white-sm);
}

.sidebar-header h1 {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: -0.01em;
    margin-bottom: 4px;
}

.sidebar-header p {
    font-size: 12px;
    opacity: 0.65;
    font-weight: 400;
}

.nav-menu {
    list-style: none;
    padding: 14px 10px;
}

.nav-item {
    margin-bottom: 2px;
}

.nav-link {
    display: block;
    padding: 10px 14px;
    color: rgba(255, 255, 255, 0.85);
    text-decoration: none;
    font-size: 14px;
    border-radius: 8px;
    transition: background-color 0.18s ease, color 0.18s ease;
}

.nav-link:hover {
    background-color: rgba(255, 255, 255, 0.10);
    color: #ffffff;
}

.nav-link.active {
    background-color: rgba(255, 255, 255, 0.18);
    color: #ffffff;
    font-weight: 600;
}

/* ── Main content ────────────────────────────────────────────────────────── */

.main-content {
    flex: 1;
    padding: 40px;
    max-width: 1200px;
}

.page-header {
    margin-bottom: 36px;
    padding-bottom: 18px;
    border-bottom: 1px solid var(--border-color);
}

.page-header h2 {
    color: var(--purple-main);
    font-size: 28px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 6px;
}

.page-header p {
    color: var(--text-light);
    font-size: 15px;
}

/* ── Cards ───────────────────────────────────────────────────────────────── */

.card {
    background: var(--bg-white);
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    padding: 30px;
    margin-bottom: 28px;
    border: 1px solid var(--border-color);
}

.card h3 {
    color: var(--purple-main);
    margin-bottom: 18px;
    font-size: 18px;
    font-weight: 600;
    letter-spacing: -0.01em;
}

/* ── Forms ───────────────────────────────────────────────────────────────── */

.form-group {
    margin-bottom: 22px;
}

.form-label {
    display: block;
    margin-bottom: 7px;
    font-weight: 500;
    color: var(--text-dark);
    font-size: 13px;
    letter-spacing: 0.01em;
}

.form-control {
    width: 100%;
    padding: 9px 13px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 14px;
    background-color: var(--bg-white);
    color: var(--text-dark);
    transition: border-color 0.18s ease, box-shadow 0.18s ease;
}

.form-control:focus {
    outline: none;
    border-color: var(--purple-mid);
    box-shadow: var(--focus-ring);
}

.form-control[readonly] {
    background-color: var(--purple-pale);
    color: var(--text-dark);
    cursor: default;
}

select.form-control {
    cursor: pointer;
    appearance: auto;
}

input[type="file"].form-control {
    padding: 7px 11px;
    cursor: pointer;
}

/* ── Buttons ─────────────────────────────────────────────────────────────── */

.btn {
    display: inline-block;
    padding: 10px 26px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.18s ease;
    letter-spacing: 0.01em;
}

.btn-primary {
    background: linear-gradient(
        135deg,
        var(--purple-mid)  0%,
        var(--purple-main) 100%
    );
    color: #ffffff;
}

.btn-primary:hover {
    background: linear-gradient(
        135deg,
        var(--purple-main)    0%,
        var(--purple-deepest) 100%
    );
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-primary:active {
    transform: translateY(0);
    box-shadow: none;
}

/* ── Alerts ──────────────────────────────────────────────────────────────── */

.alert {
    padding: 13px 18px;
    border-radius: 8px;
    margin-bottom: 22px;
    border-left: 4px solid;
    font-size: 14px;
}

.alert-success {
    background-color: var(--success-bg);
    border-color: var(--success);
    color: var(--success-text);
}

.alert-error {
    background-color: var(--error-bg);
    border-color: var(--error);
    color: var(--error-text);
}

/* ── Tool grid (homepage) ────────────────────────────────────────────────── */

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
    margin-top: 28px;
}

.tool-card {
    background: var(--bg-white);
    border-radius: 12px;
    padding: 24px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    border-left: 4px solid var(--purple-main);
    text-decoration: none;
    color: var(--text-dark);
    display: block;
    transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.tool-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.tool-card h3 {
    color: var(--purple-main);
    margin-bottom: 8px;
    font-size: 17px;
    font-weight: 600;
}

.tool-card p {
    color: var(--text-light);
    font-size: 13px;
    line-height: 1.5;
}

/* ── Copy button ─────────────────────────────────────────────────────────── */

.copy-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    padding: 4px 10px;
    font-size: 12px;
    font-weight: 500;
    background-color: var(--purple-main);
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    opacity: 0;
    transition: opacity 0.18s ease, background-color 0.18s ease;
}

.copy-btn:hover {
    background-color: var(--purple-dark);
}

div:has(> pre.result-pre):hover .copy-btn {
    opacity: 1;
}

/* ── Responsive ──────────────────────────────────────────────────────────── */

@media (max-width: 768px) {
    .container {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
    }

    .main-content {
        padding: 20px;
    }

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