/* === Executive Edge: Enhanced Full-Page CSS === */

/* === Root Variables === */
:root {
    --primary-dark-slate: #2f3640;
    --primary-midnight-blue: #1a202c;
    --accent-gold: #fcc430;

    --background-light-grey: #f0f2f5;
    --card-background: #ffffff;
    --border-soft: #e0e6ed;

    --text-dark: #34495e;
    --text-light: #fefefe;
    --text-subtle: #8a96a3;

    --shadow-subtle: 0 4px 8px rgba(0, 0, 0, 0.08);
    --shadow-elevated: 0 8px 16px rgba(0, 0, 0, 0.15);

    --success-green: #2ecc71;
    --danger-red: #e74c3c;
}

/* === Reset & Base Styles === */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--background-light-grey);
    color: var(--text-dark);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

/* === Top Navbar === */
.top-navbar {
    background-color: var(--primary-midnight-blue);
    color: var(--text-light);
    padding: 1.2rem 2rem;
    display: flex;
    justify-content: center;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow-elevated);
}
.top-navbar h1 {
    font-family: 'Montserrat', sans-serif;
    font-size: 2rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    position: relative;
    color: var(--text-light);
}
.top-navbar h1::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background-color: var(--accent-gold);
    border-radius: 2px;
}

/* === Page Wrapper === */
.page-wrapper {
    display: flex;
    flex: 1;
    width: 100%;
}

/* === Left Sidebar === */
.left-navbar {
    width: 240px;
    background-color: var(--primary-dark-slate);
    padding-top: 2rem;
    box-shadow: var(--shadow-elevated);
    flex-shrink: 0;
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
    transition: width 0.3s ease;
    z-index: 999;
}
.left-navbar ul {
    list-style: none;
}
.left-navbar li {
    margin-bottom: 0.7rem;
}
.left-navbar a {
    display: flex;
    align-items: center;
    padding: 0.95rem 1.5rem;
    color: rgba(255,255,255,0.8);
    text-decoration: none;
    font-weight: 500;
    border-left: 5px solid transparent;
    transition: all 0.2s ease;
    border-radius: 5px;
}
.left-navbar a:hover {
    background-color: rgba(255,255,255,0.05);
    color: var(--text-light);
    border-left-color: var(--accent-gold);
}
.left-navbar a.active {
    background-color: rgba(255,255,255,0.12);
    color: var(--text-light);
    border-left-color: var(--accent-gold);
    font-weight: 600;
}

/* === Main Content === */
.main-content {
    flex-grow: 1;
    padding: 3rem 3.5rem;
    display: flex;
    flex-direction: column;
    gap: 2.5rem;
    background-color: var(--background-light-grey);
    animation: fadeInSlideUp 0.8s ease-out forwards;
}
@keyframes fadeInSlideUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* === Form & Section Cards === */
form, .section {
    background-color: var(--card-background);
    border: 1px solid var(--border-soft);
    border-radius: 10px;
    padding: 2.5rem;
    box-shadow: var(--shadow-subtle);
    transition: all 0.3s ease-in-out;
}
form:hover, .section:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-elevated);
    border-color: var(--accent-gold);
}
form h2, .section h2 {
    font-family: 'Montserrat', sans-serif;
    text-align: center;
    font-size: 2rem;
    margin-bottom: 2rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    position: relative;
}
form h2::after, .section h2::after {
    content: '';
    position: absolute;
    bottom: -6px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background-color: var(--accent-gold);
    border-radius: 2px;
}

/* === Latest Invoice No === */
form h3.latest-invoice-no {
    font-family: 'Montserrat', sans-serif;
    color: var(--danger-red);
    font-size: 1.15rem;
    font-weight: 600;
    text-align: center;
    margin: -1.5rem auto 1.5rem;
    padding: 10px 20px;
    background-color: rgba(231,76,60,0.08);
    border-radius: 8px;
    border: 1px solid rgba(231,76,60,0.2);
    width: fit-content;
}

/* === Section Titles === */
.section h3 {
    font-family: 'Montserrat', sans-serif;
    font-size: 1.6rem;
    margin-bottom: 1.8rem;
    font-weight: 600;
    display: flex;
    align-items: center;
}
.section h3::before {
    content: '';
    width: 6px;
    height: 35px;
    background-color: var(--accent-gold);
    border-radius: 3px;
    margin-right: 1rem;
}

/* === Input Fields === */
.input-group {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.8rem 2rem;
}
.input-group > div {
    display: flex;
    flex-direction: column;
    position: relative;
}
label {
    font-family: 'Montserrat', sans-serif;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 0.6rem;
    font-size: 0.95rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
input[type="text"],
input[type="number"],
input[type="date"],
select,
textarea {
    padding: 12px 14px;
    border: 1px solid var(--border-soft);
    border-radius: 8px;
    font-size: 1rem;
    background-color:rgb(252, 252, 190);
    color: var(--text-dark);
    font-weight: 400;
    line-height: 1.4;
    width: 100%;
    transition: all 0.25s ease-in-out;
}
input[type="text"]:focus,
input[type="number"]:focus,
input[type="date"]:focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--accent-gold);
    box-shadow: 0 0 0 3px rgba(252,196,48,0.25);
    background-color: var(--card-background);
}
textarea {
    min-height: 120px;
    resize: vertical;
}

/* === Table Styles === */
.table-container {
    overflow-x: auto;
    border-radius: 10px;
    background-color: var(--card-background);
    border: 1px solid var(--border-soft);
    box-shadow: var(--shadow-subtle);
}
#items-table {
    width: 100%;
    border-collapse: collapse;
}
#items-table th, #items-table td {
    padding: 1rem 1.2rem;
    font-size: 0.95rem;
    text-align: left;
    border-bottom: 1px solid var(--border-soft);
}
#items-table th {
    background-color: var(--primary-dark-slate);
    color: var(--text-light);
    font-weight: 600;
    text-transform: uppercase;
}
#items-table tbody tr:hover {
    background-color: rgba(252,196,48,0.05);
}
#items-table tbody tr:nth-child(even) {
    background-color: var(--background-light-grey);
}
#items-table input, #items-table select {
    padding: 10px 12px;
    font-size: 0.95rem;
}

/* === Add Row & Buttons === */
.add-row-btn, button[type="submit"] {
    background-color: var(--accent-gold);
    color: var(--primary-dark-slate);
    border: none;
    padding: 12px 28px;
    font-size: 1rem;
    font-weight: 700;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.25s ease;
    margin-top: 1.5rem;
}
.add-row-btn:hover, button[type="submit"]:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-elevated);
    filter: brightness(1.08);
}
button[type="submit"] {
    background-color: var(--primary-midnight-blue);
    color: var(--text-light);
    margin: 3rem auto 0;
    padding: 14px 40px;
    font-size: 1.1rem;
}

/* Remove row */
.remove-row-btn {
    background-color: var(--danger-red);
    color: var(--text-light);
    padding: 7px 14px;
    font-size: 0.85rem;
    border-radius: 6px;
}

/* === Grand Total Field === */
#grand_total {
    background-color: var(--card-background);
    border: 2px solid var(--accent-gold);
    color: var(--primary-dark-slate);
    font-size: 1.5rem;
    font-weight: 700;
    text-align: right;
    padding: 14px 20px;
    width: fit-content;
    margin-left: auto;
    display: block;
    margin-top: 2rem;
}

/* === Responsive Media Queries === */
@media (max-width: 1200px) {
    .main-content { padding: 2.5rem; gap: 2rem; }
    .left-navbar { width: 200px; }
}
@media (max-width: 1024px) {
    .page-wrapper { flex-direction: column; }
    .left-navbar { width: 100%; height: auto; position: static; border-bottom: 1px solid rgba(255,255,255,0.1); }
    .left-navbar ul { display: flex; justify-content: flex-start; flex-wrap: nowrap; padding: 0.8rem 1rem; }
    .left-navbar li { margin: 0 1rem; }
    .left-navbar a { border-left: none; border-bottom: 4px solid transparent; padding: 0.8rem 1rem; }
    .main-content { padding: 2rem; }
    form, .section { padding: 2rem; }
}
@media (max-width: 768px) {
    .top-navbar h1 { font-size: 1.8rem; }
    .section h3 { font-size: 1.3rem; margin-bottom: 1.2rem; }
    .input-group { grid-template-columns: 1fr; gap: 1.5rem; }
    input[type="text"], input[type="number"], select, textarea { font-size: 0.95rem; padding: 10px 12px; }
    #items-table th, #items-table td { font-size: 0.9rem; padding: 0.9rem 1rem; }
    .add-row-btn, button[type="submit"] { padding: 10px 22px; font-size: 0.95rem; }
    #grand_total { font-size: 1.3rem; padding: 12px 16px; }
}