:root {
    --sidebar-width: 240px;
    --sidebar-collapsed-width: 74px;
    --sidebar-bg: #fff;
    --sidebar-shadow: 4px 0 24px rgba(26,117,255,0.07);
    --accent-400: #1a75ff;
    --accent-main: #FF9494;
    --radius-xl: 20px;
    --radius-lg: 14px;
    --radius-md: 10px;
    --shadow-1: 0 6px 24px rgba(7, 17, 27, 0.06);
    --shadow-2: 0 10px 40px rgba(7, 17, 27, 0.08);
    --muted: #6b7280;
    --surface: #fff;
    --bg: #f6f8fb;
    --font-main-size: 0.89em;
    --font-nav-size: 1em;
    --font-btn-size: 1em;
    --font-content-size: 0.89em;
    --font-h1-size: 1.18em;
    --font-h2-size: 1.02em;
    --font-h3-size: 0.98em;
    --transition: 0.22s cubic-bezier(.4,0,.2,1);
}

/* ================= BASE ================ */
* { box-sizing: border-box; }
body {
    margin: 0;
    font-family: Inter, "Trirong", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
    font-size: var(--font-main-size);
    color: #0b1220;
    background: var(--bg);
    line-height: 1.6;
    transition: background .18s;
}
body.no-scroll { overflow: hidden; }

.app-shell {
    display: grid;
    grid-template-columns: var(--sidebar-width) 1fr;
    min-height: 100vh;
    background: var(--bg);
    transition: grid-template-columns var(--transition);
}

/* ================= SIDEBAR (HYBRID) ================ */
.app-sidebar {
    position: sticky;
    top: 0;
    left: 0;
    height: 100%;
    width: var(--sidebar-width);
    background: var(--sidebar-bg);
    border-right: 1px solid #e5e7eb;
    box-shadow: var(--sidebar-shadow);
    padding: 32px 0 18px 0;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    z-index: 1001;
    transition: width var(--transition), box-shadow var(--transition);
    overflow-x: hidden;
}
.app-sidebar.collapsed {
    width: var(--sidebar-collapsed-width);
}
.app-sidebar .brand {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 10px;
    padding: 0 22px 10px 22px;
    margin-bottom: 36px;
    min-height: 54px;
    transition: padding var(--transition);
}
.app-sidebar.collapsed .brand-text {
    display: none;
}
.brand-logo {
    width: 40px; height: 40px; border-radius: 12px;
    box-shadow: 0 4px 12px rgba(26,117,255,0.11);
}
.brand-tag { color: var(--muted); font-size: 12px; }

.nav {
    display: flex; flex-direction: column; gap: 3px;
}
.nav-item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 10px 22px 10px 22px;
    border: none;
    background: none;
    color: var(--muted);
    font-size: var(--font-nav-size);
    font-weight: 600;
    border-radius: 10px;
    margin: 2px 0;
    cursor: pointer;
    transition: background var(--transition), color var(--transition), padding var(--transition);
    outline: none;
    min-height: 44px;
    position: relative;
}
.nav-item svg {
    width: 22px; height: 22px; display: block;
    transition: fill var(--transition), color var(--transition);
    flex-shrink: 0;
}
.nav-item span { transition: opacity var(--transition); }
.app-sidebar.collapsed .nav-item span {
    opacity: 0;
    width: 0;
    overflow: hidden;
    pointer-events: none;
}
.nav-item:focus { outline: 2px solid var(--accent-400); z-index: 1; }
.nav-item:hover, .nav-item:active {
    background: var(--accent-400, #e6f0ff);
    color: #fff;
}
.nav-item.nav-active {
    background: linear-gradient(90deg, var(--accent-400) 0%, var(--accent-main) 100%);
    color: #fff;
    font-weight: bold;
}
.nav-item.nav-active svg { color: #fff; }

.sidebar-footer {
    margin-top: auto;
    display: flex; gap: 10px; align-items: center;
    padding: 0 22px;
}
.app-sidebar.collapsed .sidebar-footer {
    flex-direction: column; gap: 6px; padding: 0 6px;
}
.icon-btn {
    background: transparent;
    border: 1px solid #e5e7eb;
    border-radius: 10px;
    padding: 7px 11px;
    color: var(--muted);
    cursor: pointer;
    font-size: 1em;
    transition: background var(--transition), color var(--transition), border var(--transition);
}
.icon-btn:hover { background: #f1f5ff; color: var(--accent-400); border-color: var(--accent-400); }

/* Sidebar collapse/expand toggle button */
#sidebar-collapse-btn {
    position: absolute;
    top: 16px;
    right: -18px;
    z-index: 1010;
    background: #fff;
    border: 1px solid #e5e7eb;
    border-radius: 50%;
    box-shadow: 0 2px 6px rgba(26,117,255,0.08);
    width: 36px; height: 36px;
    display: flex; align-items: center; justify-content: center;
    cursor: pointer;
    color: var(--muted);
    transition: background var(--transition), color var(--transition), border var(--transition);
}
#sidebar-collapse-btn:hover { color: var(--accent-400); border-color: var(--accent-400); background: #f1f5ff; }

/* ================= MAIN AREA ================ */
.app-main-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
    background: var(--bg);
    min-height: 100vh;
}
.app-content {
    width: 100%;
    max-width: 940px;
    margin: 0 auto;
    padding: 36px 0 24px 0;
    min-height: 70vh;
}

.app-topbar {
    position: sticky; top: 0;
    width: 100%;
    max-width: 940px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: linear-gradient(180deg, #fff 90%, #f6f8fb 100%);
    border-radius: 0 0 14px 14px;
    border-bottom: 1px solid #e5e7eb;
    box-shadow: 0 1px 10px rgba(26,117,255,0.03);
    padding: 10px 32px 10px 18px;
    z-index: 700;
    min-height: 58px;
}

.topbar-left { display: flex; gap: 18px; align-items: center; flex: 1 1 0; }
.topbar-right { display: flex; gap: 16px; align-items: center; }

#sidebar-toggle { display: none; } /* แสดงเฉพาะบน mobile */

.search {
    flex: 1 1 0;
    max-width: 300px;
}
.search input{
    width: 100%;
    padding: 10px 14px;
    border-radius: 10px;
    border: 1px solid #e5e7eb;
    background: #f8fbff;
    outline: none;
    font-size: var(--font-main-size);
    color: #222;
    transition: box-shadow .14s, border .14s;
}
.search input:focus{ box-shadow: 0 6px 18px rgba(26,117,255,0.07); border-color: var(--accent-400); }

.user{ display:flex; align-items:center; gap:8px; color:var(--muted); font-size: var(--font-main-size);}
.user-avatar{ width:36px;height:36px;border-radius:10px;background:linear-gradient(90deg,var(--accent-400),var(--accent-main)); display:flex;align-items:center;justify-content:center;color:white;font-weight:700; font-size: 1em;}

.card{
    background: var(--surface);
    padding: 26px 34px 26px 34px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-1);
    border: 1px solid #e5e7eb;
    margin: 30px 0;
    max-width: 100%;
}
.card.elevated{ box-shadow: var(--shadow-2); }
.card-plain{ background: transparent; box-shadow:none; border: none; padding:0; margin: 0; }

.hero-inner{
    display: grid;
    grid-template-columns: 1.15fr 0.85fr;
    gap: 38px;
    align-items: center;
    padding: 0;
    width: 100%;
    min-height: 240px;
}
.hero-left{ padding: 0 0 0 10px; }
.hero-title,
h1 {
    font-family:"Trirong", serif;
    font-size: calc(2.1 * var(--font-h1-size) * 1.2em);
    margin: 0;
    display: inline-block;
    background: linear-gradient(45deg, var(--accent-400), var(--accent-main));
    -webkit-background-clip: text;
    color: transparent;
    font-weight: 800;
    letter-spacing: 0.5px;
}
.hero-subtitle{
    margin-top: 14px;
    color: var(--muted);
    font-size: var(--font-h2-size);
    max-width: 56ch;
    line-height: 1.7;
    letter-spacing: 0.01em;
}
.hero-actions{ margin-top:22px; display:flex; gap:16px; align-items:center; flex-wrap:wrap; }
.app-button{
    display:inline-flex;
    align-items:center;
    gap:10px;
    border-radius: 12px;
    padding: 10px 18px;
    text-decoration:none;
    font-weight:700;
    font-size: var(--font-btn-size);
    transition: all .18s;
    border: 1px solid #e5e7eb;
    color: var(--accent-400);
    background: #fff;
    box-shadow: 0 4px 12px rgba(11,18,32,0.06);
    outline: none;
}
.app-button svg{ opacity:0.95; }
.app-button.primary{
    background: linear-gradient(90deg, var(--accent-400), var(--accent-main));
    color: #fff;
    border: none;
    box-shadow: 0 7px 18px rgba(26,117,255,0.12);
}
.app-button.outline{
    background: transparent;
    border: 1px solid var(--accent-400);
    color: var(--accent-400);
}
.app-button:hover{ transform: translateY(-1.5px) scale(1.03); }
.app-button:focus{ outline: 2px solid var(--accent-400); }

.section-title,
h2 {
    font-size: calc(1.03 * var(--font-h2-size) * 1.11em);
    font-weight: 700;
    margin: 0 0 10px 0;
    background: linear-gradient(45deg, var(--accent-400), var(--accent-500));
    -webkit-background-clip: text;
    color: var(--accent-400);
    letter-spacing: 0.02em;
}

h3 {
    font-size: var(--font-h3-size);
    font-weight: 700;
    color: var(--accent-400);
    margin: 0 0 10px 0;
}

.content-text{
    font-size: var(--font-content-size);
    color: var(--muted);
    line-height: 1.85;
    margin-top: 18px;
    max-width: 72ch;
}
.content-text strong{ color: var(--accent-400); font-weight:700; }
.content-text em{ color: var(--accent-400); font-weight:600; padding-bottom:2px; border-bottom:2px solid var(--accent-main); }

.button-grid{
    display:flex;
    gap:16px;
    flex-wrap:wrap;
    align-items:center;
    margin: 8px 0;
}
.grid-cards .card-body{ padding-top:12px; }
.grid-cards .button-grid{ margin-top:10px; }

.app-footer{
    margin-top: auto;
    background: linear-gradient(180deg, rgba(26,26,34,0.02), rgba(255,255,255,0.02));
    padding: 20px 0 16px 0;
    border-radius: 0 0 14px 14px;
    text-align:center;
    color:var(--muted);
    border-top: 1px solid #e5e7eb;
    width: 100%;
    max-width: 940px;
    margin: 0 auto;
    font-size: 0.93em;
}

/* ============ MOBILE ============= */
@media (max-width: 900px) {
    .app-shell{ grid-template-columns: 1fr; }
    .app-sidebar {
        position: fixed;
        left: 0; top: 0;
        width: 88vw;
        max-width: 340px;
        height: 100vh;
        z-index: 1001;
        transform: translateX(-100%);
        transition: transform var(--transition);
        border-radius: 0 18px 18px 0;
        box-shadow: 4px 0 32px rgba(30,64,175,0.18);
        border-right: none;
        padding-bottom: 36px;
    }
    .app-sidebar.open { transform: translateX(0); }
    .app-sidebar.collapsed { width: 88vw; }
    .sidebar-footer { flex-direction: row; gap: 10px; }
    #sidebar-collapse-btn { display: none; }
    #sidebar-toggle { display: inline-flex; }
    .app-main-area, .app-content, .app-topbar, .app-footer { max-width: 100vw; }
    .hero-inner{ grid-template-columns: 1fr; gap: 18px; }
    .hero-right{ display:none; }
    .search { max-width: 100vw; }
    .search input{ font-size: 1.12em; }
}
@media (max-width: 600px) {
    .card { padding: 12px 6px; }
    .app-footer { font-size: 0.99em; }
    .nav-item { font-size: 1.08em; }
    .hero-title { font-size: 1.55em; }
    .section-title { font-size: 1.13em; }
    .app-topbar { padding: 10px 7px; }
    .app-content { padding: 12px 0 6px 0;}
}

/* Backdrop for mobile overlay */
.sidebar-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(3,6,23,0.52);
    opacity: 0;
    pointer-events: none;
    transition: opacity .22s;
    z-index: 1000;
}
.sidebar-backdrop.open {
    opacity: 1;
    pointer-events: auto;
}

/* Tiny polish */
a { color: inherit; }
button { font: inherit; background: none; border: none; }