/* ========================================
   IMPORT & VARIABILI (coerenti col portfolio)
   ======================================== */

@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:wght@400;700;900&family=Inter:wght@300;400;500;600&display=swap');

:root {
    --bg-color: #070707;
    --text-color: #FCF7F8;
    --accent-color: #961114;
    --secondary-bg: #1a1a1a;
    --border-color: rgba(252, 247, 248, 0.08);
    --nav-height: 70px;
    --font-display: 'Playfair Display', Georgia, serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --transition-theme: background-color 0.5s cubic-bezier(0.4,0,0.2,1), color 0.5s cubic-bezier(0.4,0,0.2,1);

    /* Colori categorie – saturati ma controllati */
    --c-alkali:      #e74c3c;
    --c-alkaline:    #e67e22;
    --c-transition: #f1c40f;
    --c-other-metal:#2ecc71;
    --c-metalloid:  #1abc9c;
    --c-nonmetal:   #3498db;
    --c-halogen:    #9b59b6;
    --c-noble:      #34495e;
    --c-lanthanide: #e84393;
    --c-actinide:   #d63384;
}

body.light-theme {
    --bg-color: #FCF7F8;
    --text-color: #070707;
    --secondary-bg: #eee;
    --border-color: rgba(7,7,7,0.08);
    --c-noble: #5d6d7e;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: var(--font-body);
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: var(--transition-theme);
    min-height: 100vh;
    overflow-x: auto;
}

/* ========================================
   NAVBAR (copia esatta dal portfolio)
   ======================================== */

.navbar {
    position: fixed; top:0; left:0; right:0; z-index:1000;
    background-color: rgba(7,7,7,0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition-theme);
}
body.light-theme .navbar { background-color: rgba(252,247,248,0.85); }

.navbar-container {
    height: var(--nav-height);
    padding: 0 2rem;
    display: flex; justify-content: space-between; align-items: center;
    max-width: 1800px; margin: 0 auto;
}
.navbar-logo { display:flex; align-items:center; gap:0.75rem; }
.logo-icon { width: auto; height: 40px; flex-shrink: 0; }
.logo-text { font-family: var(--font-display); font-size:1.4rem; font-weight:700; letter-spacing:-0.02em; }
.navbar-links { display:flex; align-items:center; gap:1.5rem; }
.nav-link { color: var(--text-color); text-decoration:none; font-size:0.9rem; font-weight:500; transition: color 0.2s; }
.nav-link:hover { color: var(--accent-color); }

.theme-toggle {
    background:none; border:1px solid var(--border-color); border-radius:50%;
    width:38px; height:38px; display:flex; align-items:center; justify-content:center;
    cursor:pointer; color: var(--text-color); transition: all 0.2s;
    position: relative;
}
.theme-toggle:hover { border-color: var(--accent-color); transform:rotate(180deg); }
.sun-icon, .moon-icon { position:absolute; transition: opacity 0.2s, transform 0.2s; }
.sun-icon { opacity:0; transform:rotate(-90deg); }
.moon-icon { opacity:1; transform:rotate(0); }
body.light-theme .sun-icon { opacity:1; transform:rotate(0); }
body.light-theme .moon-icon { opacity:0; transform:rotate(90deg); }

/* ========================================
   LEGENDA
   ======================================== */

.legend {
    position: fixed;
    top: calc(var(--nav-height) + 12px);
    left: 50%;
    transform: translateX(-50%);
    z-index: 90;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.7rem 1.4rem;
    padding: 0.7rem 1.4rem;
    background: rgba(7,7,7,0.75);
    backdrop-filter: blur(14px);
    border-radius: 10px;
    border: 1px solid var(--border-color);
}
body.light-theme .legend { background: rgba(252,247,248,0.85); }

.legend-item {
    display: flex; align-items: center; gap: 0.4rem;
    font-size: 0.72rem; font-weight: 500; letter-spacing: 0.02em;
    color: var(--text-color); opacity: 0.85;
}
.legend-swatch {
    width: 11px; height: 11px; border-radius: 3px;
    box-shadow: 0 0 6px currentColor;
}

/* ========================================
   GRIGLIA TAVOLA PERIODICA
   ======================================== */

.periodic-wrapper {
    padding-top: calc(var(--nav-height) + 72px);
    padding-bottom: 60px;
    min-height: 100vh;
    display: flex;
    align-items: flex-start;
    justify-content: center;
    padding-left: 1rem;
    padding-right: 1rem;
}

.periodic-grid {
    display: grid;
    grid-template-columns: repeat(18, 1fr);
    gap: 3px;
    width: 100%;
    max-width: 1450px;
}

/* ========================================
   SINGOLO ELEMENTO
   ======================================== */

.element {
    aspect-ratio: 1;
    border-radius: 6px;
    border: 1px solid transparent;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    position: relative;
    z-index: 1;
    transition: transform 0.25s cubic-bezier(0.34,1.56,0.64,1),
                box-shadow 0.25s ease,
                border-color 0.2s ease;
    overflow: visible;
    user-select: none;
    -webkit-user-select: none;
}

.element .el-number {
    font-size: 0.55vw;
    font-weight: 600;
    opacity: 0.7;
    line-height: 1;
    margin-bottom: 1px;
}

.element .el-symbol {
    font-family: var(--font-display);
    font-size: 1.35vw;
    font-weight: 700;
    line-height: 1;
    letter-spacing: -0.02em;
}

.element .el-name {
    font-size: 0.42vw;
    font-weight: 400;
    opacity: 0.65;
    line-height: 1;
    margin-top: 2px;
    text-align: center;
    max-width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    padding: 0 1px;
}

.element .el-mass {
    font-size: 0.38vw;
    opacity: 0.45;
    margin-top: 1px;
    line-height: 1;
}

/* Colori di sfondo per categoria */
.element[data-cat="alkali"]     { background: color-mix(in srgb, var(--c-alkali) 18%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-alkali) 30%, transparent); }
.element[data-cat="alkaline"]   { background: color-mix(in srgb, var(--c-alkaline) 18%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-alkaline) 30%, transparent); }
.element[data-cat="transition"] { background: color-mix(in srgb, var(--c-transition) 14%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-transition) 25%, transparent); }
.element[data-cat="other-metal"]{ background: color-mix(in srgb, var(--c-other-metal) 18%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-other-metal) 30%, transparent); }
.element[data-cat="metalloid"]  { background: color-mix(in srgb, var(--c-metalloid) 18%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-metalloid) 30%, transparent); }
.element[data-cat="nonmetal"]   { background: color-mix(in srgb, var(--c-nonmetal) 20%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-nonmetal) 35%, transparent); }
.element[data-cat="halogen"]    { background: color-mix(in srgb, var(--c-halogen) 18%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-halogen) 30%, transparent); }
.element[data-cat="noble"]      { background: color-mix(in srgb, var(--c-noble) 22%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-noble) 35%, transparent); }
.element[data-cat="lanthanide"] { background: color-mix(in srgb, var(--c-lanthanide) 18%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-lanthanide) 30%, transparent); }
.element[data-cat="actinide"]   { background: color-mix(in srgb, var(--c-actinide) 18%, var(--bg-color)); border-color: color-mix(in srgb, var(--c-actinide) 30%, transparent); }

/* ========================================
   HOVER – zoom + glow
   ======================================== */

.element:hover {
    transform: scale(1.85);
    z-index: 999;
    box-shadow: 0 0 22px rgba(0,0,0,0.5);
    border-color: white !important;
}

.element[data-cat="alkali"]:hover     { box-shadow: 0 0 24px color-mix(in srgb, var(--c-alkali) 60%, black); }
.element[data-cat="alkaline"]:hover   { box-shadow: 0 0 24px color-mix(in srgb, var(--c-alkaline) 60%, black); }
.element[data-cat="transition"]:hover { box-shadow: 0 0 24px color-mix(in srgb, var(--c-transition) 60%, black); }
.element[data-cat="other-metal"]:hover{ box-shadow: 0 0 24px color-mix(in srgb, var(--c-other-metal) 60%, black); }
.element[data-cat="metalloid"]:hover  { box-shadow: 0 0 24px color-mix(in srgb, var(--c-metalloid) 60%, black); }
.element[data-cat="nonmetal"]:hover   { box-shadow: 0 0 24px color-mix(in srgb, var(--c-nonmetal) 60%, black); }
.element[data-cat="halogen"]:hover    { box-shadow: 0 0 24px color-mix(in srgb, var(--c-halogen) 60%, black); }
.element[data-cat="noble"]:hover      { box-shadow: 0 0 24px color-mix(in srgb, var(--c-noble) 60%, black); }
.element[data-cat="lanthanide"]:hover { box-shadow: 0 0 24px color-mix(in srgb, var(--c-lanthanide) 60%, black); }
.element[data-cat="actinide"]:hover   { box-shadow: 0 0 24px color-mix(in srgb, var(--c-actinide) 60%, black); }

/* ========================================
   PANNELLO DETTAGLIO (popup)
   ======================================== */

.detail-panel {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(140%);
    z-index: 2000;
    width: 340px;
    background: var(--secondary-bg);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 1.4rem 1.6rem;
    transition: transform 0.35s cubic-bezier(0.34,1.56,0.64,1), opacity 0.3s;
    opacity: 0;
    pointer-events: none;
    backdrop-filter: blur(10px);
}

.detail-panel.visible {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}

.detail-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.detail-symbol {
    font-family: var(--font-display);
    font-size: 3.2rem;
    font-weight: 900;
    line-height: 1;
    letter-spacing: -0.03em;
    color: var(--accent-color);
}

.detail-number {
    font-size: 0.8rem;
    font-weight: 600;
    opacity: 0.55;
    margin-top: 2px;
    letter-spacing: 0.1em;
}

.detail-name {
    font-family: var(--font-display);
    font-size: 1.15rem;
    font-weight: 700;
    margin: 6px 0 14px;
    letter-spacing: -0.01em;
}

.detail-rows {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.detail-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 5px 10px;
    border-radius: 6px;
    background: rgba(255,255,255,0.04);
}
body.light-theme .detail-row { background: rgba(0,0,0,0.05); }

.detail-label {
    font-size: 0.75rem;
    opacity: 0.55;
    font-weight: 400;
}

.detail-value {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-color);
}

/* ========================================
   GAP LANTANIDI / ATTINIDI (righe separate)
   ======================================== */

.spacer-row {
    grid-column: 1 / -1;
    height: 8px;
}

.lanthanide-label, .actinide-label {
    font-size: 0.55vw;
    font-weight: 600;
    opacity: 0.4;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    padding-right: 6px;
    grid-column: 1 / 4;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* ========================================
   RESPONSIVE
   ======================================== */

@media (max-width: 1100px) {
    .periodic-grid { gap: 2px; }
    .element .el-number { font-size: 0.7vmin; }
    .element .el-symbol { font-size: 1.8vmin; }
    .element .el-name   { font-size: 0.58vmin; }
    .element .el-mass   { font-size: 0.5vmin; }
    .element:hover { transform: scale(1.7); }
}

@media (max-width: 700px) {
    .periodic-wrapper { padding-top: calc(var(--nav-height) + 100px); }
    .legend { top: calc(var(--nav-height) + 6px); gap: 0.4rem 0.8rem; padding: 0.5rem 0.8rem; }
    .legend-item { font-size: 0.6rem; }
    .periodic-grid { gap: 1.5px; }
    .element .el-number { font-size: 0.9vmin; }
    .element .el-symbol { font-size: 2.2vmin; }
    .element .el-name   { display: none; }
    .element .el-mass   { display: none; }
    .element:hover { transform: scale(2.2); }
    .detail-panel { width: 280px; bottom: 16px; }
}

/* ========================================
   ACCESSIBILITÀ
   ======================================== */

@media (prefers-reduced-motion: reduce) {
    .element, .detail-panel { transition: none !important; }
    .element:hover { transform: scale(1.4); }
}

.element:focus-visible {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

::selection { background: var(--accent-color); color: var(--bg-color); }