/* ===== CSS Variables ===== */
:root {
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --primary-light: #3b82f6;
    --secondary-color: #10b981;
    --accent-color: #f59e0b;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --background: #ffffff;
    --background-alt: #f9fafb;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
}

/* ===== Reset & Base ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--background-alt);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.75rem; }
h4 { font-size: 1.5rem; }
h5 { font-size: 1.25rem; }
h6 { font-size: 1rem; }

p {
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: var(--primary-dark);
}

/* ===== Container ===== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* ===== Header ===== */
.site-header {
    background: var(--background);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo a {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
}

.logo svg {
    color: var(--primary-color);
}

.main-nav ul {
    list-style: none;
    display: flex;
    gap: 2rem;
    align-items: center;
}

.main-nav a {
    color: var(--text-secondary);
    font-weight: 500;
    transition: color 0.2s;
}

.main-nav a:hover {
    color: var(--primary-color);
}

.main-nav .nav-cta {
    background: var(--primary-color);
    color: white;
    padding: 0.5rem 1.25rem;
    border-radius: var(--radius-md);
    transition: background 0.2s;
}

.main-nav .nav-cta:hover {
    background: var(--primary-dark);
    color: white;
}

/* ===== Main Content ===== */
#content {
    flex: 1;
    padding: 3rem 0;
}

/* ===== Buttons ===== */
.button, button[type="submit"], input[type="submit"], 
.button-primary, a.button, a.button-primary {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
}

.button:hover, button[type="submit"]:hover, 
.button-primary:hover, a.button:hover, a.button-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
    color: white;
}

.button:active {
    transform: translateY(0);
}

/* ===== Forms ===== */
label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-primary);
}

input[type="text"],
input[type="email"],
input[type="number"],
input[type="tel"],
input[type="password"],
input[type="file"],
select,
textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.2s, box-shadow 0.2s;
}

input:focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.u-full-width {
    width: 100%;
}

/* ===== Grid System ===== */
.row {
    display: flex;
    flex-wrap: wrap;
    margin: 0 -0.75rem;
}

.row > * {
    padding: 0 0.75rem;
}

.twelve.columns { width: 100%; }
.eight.columns { width: 66.666%; }
.six.columns { width: 50%; }
.four.columns { width: 33.333%; }
.three.columns { width: 25%; }

@media (max-width: 768px) {
    .columns {
        width: 100% !important;
    }
}

/* ===== Cards ===== */
.part-item {
    background: var(--background);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: box-shadow 0.2s;
}

.part-item:hover {
    box-shadow: var(--shadow-md);
}

/* ===== Progress Bar ===== */
progress {
    width: 100%;
    height: 8px;
    border: none;
    border-radius: var(--radius-sm);
    background: var(--border-color);
}

progress::-webkit-progress-bar {
    background: var(--border-color);
    border-radius: var(--radius-sm);
}

progress::-webkit-progress-value {
    background: var(--primary-color);
    border-radius: var(--radius-sm);
}

progress::-moz-progress-bar {
    background: var(--primary-color);
    border-radius: var(--radius-sm);
}

/* ===== Messages & Alerts ===== */
.flash-container {
    position: fixed;
    top: 1rem;
    right: 1rem;
    z-index: 1000;
    max-width: 400px;
}

.flash {
    background: var(--background);
    border-left: 4px solid var(--primary-color);
    padding: 1rem;
    margin-bottom: 0.5rem;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.flash.success {
    border-left-color: var(--secondary-color);
}

.flash.error {
    border-left-color: #ef4444;
}

.flash-close-btn {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    padding: 0;
    margin-left: 1rem;
}

/* ===== Footer ===== */
.site-footer {
    background: var(--text-primary);
    color: white;
    padding: 3rem 0 1rem;
    margin-top: auto;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    color: white;
    margin-bottom: 1rem;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.8);
}

.footer-section ul {
    list-style: none;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
}

.footer-section a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 1.5rem;
    text-align: center;
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.875rem;
}

/* ===== Home Page Specific ===== */
.hero-section {
    text-align: center;
    padding: 4rem 0;
}

.hero-section h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero-section .button-primary {
    font-size: 1.125rem;
    padding: 1rem 2rem;
}

/* ===== Quote Workflow Specific ===== */
#uploadProgress {
    background: var(--background);
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

#uploadResult,
#totalResult {
    animation: fadeIn 0.3s;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

.part-result {
    min-height: 60px;
}

/* ===== Responsive Design ===== */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    .main-nav ul {
        flex-direction: column;
        gap: 0.5rem;
    }
    
    h1 { font-size: 2rem; }
    h2 { font-size: 1.75rem; }
    
    .hero-section h1 {
        font-size: 2rem;
    }
}

/* ===== Utility Classes ===== */
.text-center { text-align: center; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }