:root {
    /* Colors */
    --primary-color: #ff9d00;
    --primary-light: #ffba4d;
    --primary-dark: #cc7d00;
    --secondary-color: #0c0e12;
    --bg-color: #0a0c10;
    --card-bg: rgba(255, 255, 255, 0.03);
    --border-color: rgba(255, 255, 255, 0.1);
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --error-color: #ff4d4d;
    --success-color: #00e676;

    /* Typography */
    --font-main: 'Outfit', sans-serif;

    /* Transitions */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: var(--font-main);
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Background elements */
.bg-glow {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 10% 20%, rgba(255, 157, 0, 0.05) 0%, transparent 40%),
        radial-gradient(circle at 90% 80%, rgba(255, 157, 0, 0.05) 0%, transparent 40%);
    pointer-events: none;
    z-index: -1;
}

/* Header */
header {
    padding: 2rem;
    display: flex;
    justify-content: center;
    align-items: center;
    position: absolute;
    top: 0;
    width: 100%;
    z-index: 10;
}

.logo-container {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.logo-container span {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.sep {
    width: 1px;
    height: 30px;
    background: var(--border-color);
}

/* Hero Section */
.hero {
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 2rem;
    position: relative;
    background: linear-gradient(rgba(10, 12, 16, 0.8), rgba(10, 12, 16, 0.9)),
        url('solar_plant_hero.png') no-repeat center center;
    background-size: cover;
}

.hero-content {
    max-width: 800px;
    animation: fadeInUp 1s ease-out;
}

.hero h1 {
    font-size: clamp(2.5rem, 5vw, 4.5rem);
    font-weight: 800;
    margin-bottom: 1.5rem;
    background: linear-gradient(to right, #fff, #ff9d00);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    font-size: clamp(1rem, 1.2vw, 1.25rem);
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

/* Event Details Grid */
.event-details {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.detail-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: var(--card-bg);
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    border: 1px solid var(--border-color);
    backdrop-filter: blur(10px);
    font-size: 0.95rem;
    white-space: nowrap;
}

.detail-item i {
    color: var(--primary-color);
}

.btn-primary {
    display: inline-block;
    background: var(--primary-color);
    color: #000;
    padding: 1.1rem 2.8rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    font-size: 1.05rem;
    transition: var(--transition);
    box-shadow: 0 10px 20px rgba(255, 157, 0, 0.15);
    border: none;
    cursor: pointer;
}

.btn-primary:active {
    transform: scale(0.98);
}

.btn-primary:hover {
    background: var(--primary-light);
    transform: translateY(-3px);
    box-shadow: 0 15px 30px rgba(255, 157, 0, 0.25);
}

/* Form Section */
.form-section {
    padding: 6rem 1.25rem;
    display: flex;
    justify-content: center;
    align-items: center;
}

.form-card {
    background: var(--card-bg);
    backdrop-filter: blur(25px);
    border: 1px solid var(--border-color);
    padding: clamp(1.5rem, 5vw, 3.5rem);
    border-radius: 32px;
    width: 100%;
    max-width: 600px;
    box-shadow: 0 40px 100px -20px rgba(0, 0, 0, 0.6);
}

.form-header {
    margin-bottom: 2.5rem;
    text-align: center;
}

.form-header h2 {
    font-size: clamp(1.5rem, 4vw, 2.25rem);
    margin-bottom: 0.5rem;
    font-weight: 700;
}

.form-header p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.registration-form {
    display: grid;
    gap: 1.75rem;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
}

.input-group label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    transition: var(--transition);
    margin-left: 0.5rem;
}

.input-group input,
.input-group select {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-color);
    padding: 1rem 1.25rem;
    border-radius: 16px;
    color: #fff;
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
    -webkit-appearance: none;
    appearance: none;
    /* Mobile reset */
}

.input-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    background: rgba(255, 255, 255, 0.07);
    box-shadow: 0 4px 20px rgba(255, 157, 0, 0.1);
}

/* Custom Multiple Choice (Selection Buttons) */
.options-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
}

@media (min-width: 480px) {
    .options-grid {
        grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    }
}

.option-item {
    position: relative;
}

.option-item input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
    height: 0;
    width: 0;
}

.option-label {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.85rem 0.5rem;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    text-align: center;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 500;
    transition: var(--transition);
    height: 100%;
}

.option-item input:checked~.option-label {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: #000;
    font-weight: 700;
    box-shadow: 0 8px 16px rgba(255, 157, 0, 0.2);
}

.option-label:hover {
    background: rgba(255, 255, 255, 0.08);
}

.form-footer {
    margin-top: 1rem;
}

.submit-btn {
    width: 100%;
}

/* Page Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(40px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Mobile Specific Optimizations */
@media (max-width: 768px) {
    .hero {
        padding: 1.5rem;
        height: auto;
        min-height: 90vh;
    }

    .hero-content {
        margin-top: 4rem;
    }

    header {
        padding: 1.5rem 1rem;
    }

    .logo-container span {
        font-size: 1.25rem;
    }
}

@media (max-width: 480px) {
    .event-details {
        flex-direction: column;
        align-items: stretch;
        gap: 0.75rem;
    }

    .detail-item {
        justify-content: center;
    }

    .form-card {
        border-radius: 24px;
    }
}

/* Utilities */
html {
    scroll-behavior: smooth;
}

/* Toast Notification */
#toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--success-color);
    color: #000;
    padding: 1rem 2rem;
    border-radius: 50px;
    font-weight: 600;
    transition: var(--transition);
    z-index: 100;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
    width: calc(100% - 3rem);
    max-width: 400px;
    text-align: center;
}

#toast.visible {
    transform: translateX(-50%) translateY(0);
}

/* Footer Section */
footer {
    padding: 4rem 2rem 2rem;
    border-top: 1px solid var(--border-color);
    background: rgba(10, 12, 16, 0.5);
    backdrop-filter: blur(10px);
    margin-top: 4rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    text-align: center;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 1rem;
    opacity: 0.8;
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
}

.footer-socials {
    display: flex;
    gap: 1.5rem;
}

.footer-socials a {
    color: var(--text-secondary);
    font-size: 1.25rem;
    transition: var(--transition);
}

.footer-socials a:hover {
    color: var(--primary-color);
    transform: translateY(-3px);
}

.footer-bottom {
    font-size: 0.8rem;
    color: var(--text-secondary);
    opacity: 0.5;
}

@media (max-width: 768px) {
    footer {
        padding: 3rem 1.5rem 1.5rem;
    }
}