/* ============================================================
   Certifications — Apple-style light theme
   ============================================================ */

:root {
    --bg: #fbfbfd;
    --bg-elevated: #ffffff;
    --text: #1d1d1f;
    --text-secondary: #6e6e73;
    --text-tertiary: #86868b;
    --separator: rgba(0, 0, 0, 0.08);
    --card-border: rgba(0, 0, 0, 0.06);
    --card-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 4px 16px rgba(0, 0, 0, 0.06);
    --card-shadow-hover: 0 6px 20px rgba(0, 0, 0, 0.10), 0 12px 40px rgba(0, 0, 0, 0.10);
    --accent: #0071e3;
    --radius: 18px;
    --radius-sm: 12px;
    --font: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text",
        "Helvetica Neue", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
    --ease: cubic-bezier(0.25, 0.1, 0.25, 1);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font-family: var(--font);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    line-height: 1.5;
}

/* ----------------------------------------------------------
   Header (sticky frosted-glass nav)
   ---------------------------------------------------------- */
.part1 {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    padding: 18px 20px;
    font-size: 22px;
    font-weight: 600;
    letter-spacing: -0.01em;
    color: var(--text);
    background: rgba(251, 251, 253, 0.72);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--separator);
}

.part1 > img {
    width: 30px;
    height: 30px;
}

/* Credly badge — keep the subtle blinking personality */
.credly {
    display: inline-flex;
    align-items: center;
}

.credly img {
    width: 40px;
    height: 40px;
    object-fit: contain;
    border-radius: 10px;
    animation: blink 2.4s ease-in-out infinite;
    transition: transform 0.3s var(--ease);
}

.credly img:hover {
    transform: scale(1.12);
}

@keyframes blink {
    0%, 50%, 100% { opacity: 1; }
    25%, 75% { opacity: 0.55; }
}

/* ----------------------------------------------------------
   Breadcrumb / category nav (pill buttons, horizontal scroll)
   ---------------------------------------------------------- */
.cert-nav {
    position: sticky;
    top: 60px;
    z-index: 90;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
    justify-content: center;
    width: 80%;
    margin: 0 auto;
    padding: 14px 0;
    background: rgba(251, 251, 253, 0.72);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--separator);
}

.cert-nav-item {
    flex: 0 0 auto;
    display: inline-flex;
    align-items: center;
    gap: 7px;
    padding: 8px 16px;
    border: none;
    border-radius: 980px;
    background: rgba(0, 0, 0, 0.05);
    color: var(--text-secondary);
    font-family: inherit;
    font-size: 14px;
    font-weight: 500;
    letter-spacing: -0.01em;
    white-space: nowrap;
    cursor: pointer;
    transition: background 0.2s var(--ease), color 0.2s var(--ease),
        transform 0.15s var(--ease);
}

.cert-nav-item:hover {
    background: rgba(0, 0, 0, 0.09);
    color: var(--text);
}

.cert-nav-item:active {
    transform: scale(0.96);
}

.cert-nav-item.active {
    background: var(--text);
    color: #fff;
}

.cert-nav-count {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 20px;
    height: 18px;
    padding: 0 6px;
    border-radius: 980px;
    background: rgba(0, 0, 0, 0.10);
    color: var(--text-tertiary);
    font-size: 11px;
    font-weight: 600;
    font-variant-numeric: tabular-nums;
}

.cert-nav-item.active .cert-nav-count {
    background: rgba(255, 255, 255, 0.22);
    color: #fff;
}

/* --- Per-category brand coloring (matches tag colors) ---------- */
/* Each nav item declares its brand color via --c; default state uses
   a tinted background + brand text, active state uses a solid fill. */
.nav-aws     { --c: #FF9900; }
.nav-azure   { --c: #008AD8; }
.nav-tencent { --c: #4285F4; }
.nav-alibaba { --c: #E8A400; }
.nav-postman { --c: #FF6C37; }
.nav-ibm     { --c: #054ADA; }
.nav-green   { --c: #34A853; }
.nav-udemy   { --c: #6E6E73; }
.nav-other   { --c: #6E6E73; }
.nav-pinned  { --c: #1d1d1f; }
.nav-cognitive { --c: #1AA6B7; }
.nav-rosetta   { --c: #D9A800; }
.nav-covictory { --c: #E4007F; }
.nav-momo      { --c: #3CB371; }
.nav-duolingo  { --c: #58CC02; }
.nav-easthome  { --c: #1E6FB8; }
.nav-peoplecert { --c: #702082; }

.cert-nav-item[class*="nav-"] {
    background: color-mix(in srgb, var(--c) 12%, transparent);
    color: var(--c);
}

.cert-nav-item[class*="nav-"]:hover {
    background: color-mix(in srgb, var(--c) 20%, transparent);
    color: var(--c);
}

.cert-nav-item[class*="nav-"] .cert-nav-count {
    background: color-mix(in srgb, var(--c) 16%, transparent);
    color: var(--c);
}

.cert-nav-item.active[class*="nav-"] {
    background: var(--c);
    color: #fff;
}

.cert-nav-item.active[class*="nav-"] .cert-nav-count {
    background: rgba(255, 255, 255, 0.24);
    color: #fff;
}

/* ----------------------------------------------------------
   List section — two-column grid (single column on mobile)
   ---------------------------------------------------------- */
.part3 {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
    width: 80%;
    margin: 0 auto;
    padding: 36px 0 80px;
}

/* ----------------------------------------------------------
   Cert card
   ---------------------------------------------------------- */
.cert-item {
    display: flex;
    align-items: center;
    gap: 16px;
    width: 100%;
    padding: 16px 22px;
    background: var(--bg-elevated);
    border: 1px solid var(--card-border);
    border-radius: var(--radius);
    box-shadow: var(--card-shadow);
    transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.cert-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--card-shadow-hover);
}

/* Tag — pill-shaped chip */
.cert-item .tag {
    flex: 0 0 auto;
    min-width: 92px;
    text-align: center;
    font-size: 13px;
    font-weight: 600;
    letter-spacing: 0.01em;
    padding: 5px 12px;
    border-radius: 980px;
    background: rgba(0, 0, 0, 0.04);
    white-space: nowrap;
}

/* Title */
.cert-item .title {
    flex: 1 1 auto;
    min-width: 0;
    font-size: 15px;
    font-weight: 500;
    color: var(--text);
    cursor: pointer;
    transition: color 0.2s var(--ease);
}

.cert-item .title:hover {
    color: var(--accent);
    text-decoration: none;
}

/* Date */
.cert-item .date {
    flex: 0 0 auto;
    font-size: 13px;
    color: var(--text-tertiary);
    font-variant-numeric: tabular-nums;
    white-space: nowrap;
}

/* Icon buttons (image / link) */
.cert-item .image,
.cert-item .link {
    flex: 0 0 auto;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: 50%;
    background: rgba(0, 0, 0, 0.04);
    transition: background 0.2s var(--ease), transform 0.2s var(--ease);
}

.cert-item .image:hover,
.cert-item .link:hover {
    background: rgba(0, 113, 227, 0.12);
    transform: scale(1.08);
}

.cert-item .image img,
.cert-item .link img {
    width: 18px !important;
    height: 18px;
    object-fit: contain;
    opacity: 0.75;
    transition: opacity 0.2s var(--ease);
}

.cert-item .image:hover img,
.cert-item .link:hover img {
    opacity: 1;
    transform: none;
}

/* ----------------------------------------------------------
   Tag color accents (kept from original brand palette)
   ---------------------------------------------------------- */
.aws    { color: #b35a00; background: rgba(255, 153, 0, 0.12); }
.azure  { color: #0067a5; background: rgba(0, 138, 216, 0.12); }
.tencent{ color: #2f6fe0; background: rgba(66, 133, 244, 0.12); }
.alibaba{ color: #b58a00; background: rgba(255, 165, 0, 0.16); }
.postman{ color: #d6481e; background: rgba(255, 108, 55, 0.12); }
.udemy  { color: #5a5a5e; background: rgba(0, 0, 0, 0.05); }
.other  { color: #5a5a5e; background: rgba(0, 0, 0, 0.05); }
.green  { color: #1d8a3f; background: rgba(52, 168, 83, 0.14); }

/* Language / learning brands */
.cognitive { color: #127a87; background: rgba(26, 166, 183, 0.14); }
.rosetta   { color: #9a7b00; background: rgba(255, 210, 0, 0.18); }
.covictory { color: #c00069; background: rgba(228, 0, 127, 0.10); }
.momo      { color: #2c8c5a; background: rgba(60, 179, 113, 0.14); }
.duolingo  { color: #3a8a02; background: rgba(88, 204, 2, 0.16); }
.easthome  { color: #1e6fb8; background: rgba(30, 111, 184, 0.12); }
.peoplecert { color: #702082; background: rgba(112, 32, 130, 0.12); }

.google {
    background: rgba(0, 0, 0, 0.04);
    background-image: linear-gradient(to right, #4285F4, #EA4335, #FBBC05, #34A853);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.ibm {
    color: #054ADA;
    background: rgba(5, 74, 218, 0.10);
}

/* ----------------------------------------------------------
   Image dialog (jQuery UI) — Apple-style sheet
   ---------------------------------------------------------- */
.ui-widget-overlay {
    background: rgba(0, 0, 0, 0.4);
    -webkit-backdrop-filter: blur(4px);
    backdrop-filter: blur(4px);
}

.ui-dialog {
    border: none !important;
    border-radius: 20px !important;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3) !important;
    background: var(--bg-elevated) !important;
    font-family: var(--font) !important;
    padding: 0 !important;
}

.ui-dialog .ui-dialog-titlebar {
    background: rgba(251, 251, 253, 0.8) !important;
    -webkit-backdrop-filter: blur(20px);
    backdrop-filter: blur(20px);
    border: none !important;
    border-bottom: 1px solid var(--separator) !important;
    border-radius: 0 !important;
    padding: 14px 20px !important;
}

.ui-dialog .ui-dialog-title {
    font-size: 15px !important;
    font-weight: 600 !important;
    color: var(--text) !important;
}

.ui-dialog .ui-dialog-titlebar-close {
    top: 50% !important;
    right: 16px !important;
    width: 26px !important;
    height: 26px !important;
    margin-top: -13px !important;
    background: rgba(0, 0, 0, 0.06) !important;
    border: none !important;
    border-radius: 50% !important;
    transition: background 0.2s var(--ease);
}

.ui-dialog .ui-dialog-titlebar-close:hover,
.ui-button:hover {
    background: rgba(0, 0, 0, 0.12) !important;
}

.ui-dialog .ui-dialog-content {
    padding: 16px !important;
}

.ui-dialog #cert-image {
    border-radius: 12px;
    display: block;
}

/* ----------------------------------------------------------
   Responsive
   ---------------------------------------------------------- */
@media (max-width: 600px) {
    .part1 {
        font-size: 18px;
        padding: 14px 16px;
    }

    .cert-nav {
        top: 52px;
        width: 92%;
        padding: 12px 0;
    }

    .part3 {
        grid-template-columns: 1fr;
        width: 92%;
        padding: 24px 0 60px;
    }

    .cert-item {
        gap: 10px;
        padding: 14px 16px;
        flex-wrap: wrap;
    }

    .cert-item .tag {
        min-width: 0;
        font-size: 12px;
        padding: 4px 10px;
    }

    .cert-item .title {
        flex: 1 1 100%;
        order: 3;
        font-size: 14px;
    }

    .cert-item .date {
        font-size: 12px;
    }
}