/* ===========================
   1. CSS Custom Properties
   =========================== */
:root {
    --color-bg-primary: #0B0F19;
    --color-bg-secondary: #111827;
    --color-bg-tertiary: #1E293B;
    --color-accent: #00D4AA;
    --color-accent-secondary: #6366F1;
    --color-text-primary: #F1F5F9;
    --color-text-secondary: #94A3B8;
    --color-text-tertiary: #64748B;
    --color-error: #EF4444;
    --color-success: #22C55E;
    --color-border: rgba(255, 255, 255, 0.06);

    --gradient-accent: linear-gradient(135deg, #00D4AA 0%, #6366F1 100%);

    --font-heading: 'Plus Jakarta Sans', sans-serif;
    --font-body: 'Inter', sans-serif;

    --container-max: 1200px;
    --section-padding: 60px;
    --border-radius-sm: 8px;
    --border-radius-md: 12px;
    --border-radius-lg: 16px;
    --transition: 0.3s ease;
}

/* ===========================
   2. Reset & Base
   =========================== */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

::selection {
    background: rgba(0, 212, 170, 0.3);
    color: var(--color-text-primary);
}

img {
    max-width: 100%;
    display: block;
}

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition);
}

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

ul {
    list-style: none;
}

/* Skip link */
.skip-link {
    position: absolute;
    top: -100%;
    left: 16px;
    background: var(--color-accent);
    color: var(--color-bg-primary);
    padding: 8px 16px;
    border-radius: var(--border-radius-sm);
    font-weight: 600;
    z-index: 9999;
    transition: top var(--transition);
}

.skip-link:focus {
    top: 16px;
}

/* ===========================
   3. Typography
   =========================== */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    line-height: 1.2;
    color: var(--color-text-primary);
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 1.0625rem;
    color: var(--color-text-secondary);
    max-width: 560px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 56px;
}

/* ===========================
   4. Layout
   =========================== */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 20px;
}

section {
    padding: var(--section-padding) 0;
}

/* ===========================
   5. Buttons
   =========================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 600;
    padding: 12px 28px;
    border: none;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    transition: all var(--transition);
    text-decoration: none;
    white-space: nowrap;
}

.btn--primary {
    background: var(--gradient-accent);
    color: var(--color-bg-primary);
    box-shadow: 0 4px 20px rgba(0, 212, 170, 0.2);
}

.btn--primary:hover {
    transform: scale(1.03);
    box-shadow: 0 6px 30px rgba(0, 212, 170, 0.35);
    color: var(--color-bg-primary);
}

.btn--lg {
    padding: 16px 36px;
    font-size: 1.0625rem;
}

/* ===========================
   6. Navigation
   =========================== */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(11, 15, 25, 0.6);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid transparent;
    transition: background var(--transition), border-color var(--transition);
}

.site-header.scrolled {
    background: rgba(11, 15, 25, 0.92);
    border-bottom-color: var(--color-border);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.nav__logo {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text-primary);
    text-decoration: none;
}

.nav__logo:hover {
    color: var(--color-text-primary);
}

.nav__toggle {
    display: flex;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    z-index: 1001;
}

.nav__toggle-bar {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-text-primary);
    border-radius: 2px;
    transition: all var(--transition);
}

/* Hamburger animation */
.nav-open .nav__toggle-bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.nav-open .nav__toggle-bar:nth-child(2) {
    opacity: 0;
}

.nav-open .nav__toggle-bar:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

.nav__menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 100%;
    height: 100vh;
    background: var(--color-bg-primary);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 40px;
    transition: right 0.4s ease;
}

.nav-open .nav__menu {
    right: 0;
}

.nav__list {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 32px;
}

.nav__link {
    font-size: 1.25rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    text-decoration: none;
    transition: color var(--transition);
}

.nav__link:hover {
    color: var(--color-text-primary);
}

/* ===========================
   7. Hero Section
   =========================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 120px 0 80px;
    overflow: hidden;
}

.hero__bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 60% 50% at 50% 30%, rgba(0, 212, 170, 0.12) 0%, transparent 70%),
        radial-gradient(ellipse 40% 40% at 60% 40%, rgba(99, 102, 241, 0.08) 0%, transparent 70%);
    z-index: 0;
}

.hero__bg::after {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 20%, transparent 70%);
    -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 20%, transparent 70%);
}

.hero__content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
}

.hero__title {
    font-size: 2.5rem;
    font-weight: 800;
    line-height: 1.15;
    margin-bottom: 24px;
}

.hero__title-accent {
    background: var(--gradient-accent);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero__subtitle {
    font-size: 1.0625rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
    margin-bottom: 40px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero__actions {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
}

.hero__secondary-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: color var(--transition);
}

.hero__secondary-link:hover {
    color: var(--color-accent);
}

.hero__secondary-link svg {
    transition: transform var(--transition);
}

.hero__secondary-link:hover svg {
    transform: translate(3px, -3px);
}

.hero__scroll-hint {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    color: var(--color-text-tertiary);
    animation: bounce 2s ease infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateX(-50%) translateY(0); }
    40% { transform: translateX(-50%) translateY(-8px); }
    60% { transform: translateX(-50%) translateY(-4px); }
}

/* ===========================
   8. Services Section
   =========================== */
.services {
    background: var(--color-bg-secondary);
}

.services__grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

.service-card {
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    padding: 36px 28px;
    transition: all var(--transition);
}

.service-card:hover {
    transform: translateY(-6px);
    border-color: rgba(0, 212, 170, 0.2);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3), 0 0 40px rgba(0, 212, 170, 0.05);
}

.service-card__icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--border-radius-md);
    background: rgba(0, 212, 170, 0.08);
    color: var(--color-accent);
    margin-bottom: 24px;
}

.service-card__title {
    font-size: 1.375rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.service-card__text {
    color: var(--color-text-secondary);
    line-height: 1.7;
    font-size: 0.9375rem;
}

/* ===========================
   9. Why Us Section
   =========================== */
.why-us {
    background: var(--color-bg-primary);
}

.why-us__inner {
    display: flex;
    flex-direction: column;
    gap: 48px;
}

.why-us__content .section-title {
    text-align: left;
    margin-bottom: 40px;
}

.why-us__items {
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.why-us__item {
    display: flex;
    gap: 20px;
    align-items: flex-start;
}

.why-us__item-number {
    font-family: var(--font-heading);
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--color-accent);
    flex-shrink: 0;
    width: 36px;
    padding-top: 2px;
}

.why-us__item-title {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.why-us__item-text {
    color: var(--color-text-secondary);
    font-size: 0.9375rem;
    line-height: 1.7;
}

/* Decorative orb */
.why-us__visual {
    display: flex;
    align-items: center;
    justify-content: center;
}

.why-us__orb {
    width: 240px;
    height: 240px;
    border-radius: 50%;
    background: linear-gradient(135deg, rgba(0, 212, 170, 0.15), rgba(99, 102, 241, 0.15));
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    animation: orbFloat 6s ease-in-out infinite;
}

.why-us__orb::before {
    content: '';
    position: absolute;
    inset: -20px;
    border-radius: 50%;
    border: 1px solid rgba(0, 212, 170, 0.08);
}

.why-us__orb::after {
    content: '';
    position: absolute;
    inset: -40px;
    border-radius: 50%;
    border: 1px solid rgba(99, 102, 241, 0.05);
}

.why-us__orb-inner {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: var(--gradient-accent);
    opacity: 0.3;
    filter: blur(30px);
}

@keyframes orbFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-16px); }
}

/* ===========================
   10. Contact Section
   =========================== */
.contact {
    background: var(--color-bg-secondary);
}

.contact__form-wrapper {
    max-width: 640px;
    margin: 0 auto;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.contact-form__row {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.contact-form__group {
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex: 1;
}

.contact-form__label {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-secondary);
}

.contact-form__label span {
    color: var(--color-accent);
}

.contact-form__input {
    font-family: var(--font-body);
    font-size: 1rem;
    padding: 14px 16px;
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-sm);
    color: var(--color-text-primary);
    transition: border-color var(--transition), box-shadow var(--transition);
    outline: none;
}

.contact-form__input::placeholder {
    color: var(--color-text-tertiary);
}

.contact-form__input:focus {
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(0, 212, 170, 0.1);
}

.contact-form__select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg width='12' height='8' viewBox='0 0 12 8' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1.5L6 6.5L11 1.5' stroke='%2394A3B8' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 16px center;
    padding-right: 44px;
    cursor: pointer;
}

.contact-form__textarea {
    resize: vertical;
    min-height: 120px;
}

.contact-form__submit {
    align-self: flex-start;
    margin-top: 8px;
}

.contact-form__submit-loading {
    display: none;
    animation: spin 1s linear infinite;
}

.contact-form__submit.is-loading .contact-form__submit-text {
    display: none;
}

.contact-form__submit.is-loading .contact-form__submit-loading {
    display: block;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.contact-form__status {
    font-size: 0.9375rem;
    font-weight: 500;
    padding: 0;
    border-radius: var(--border-radius-sm);
    transition: all var(--transition);
}

.contact-form__status.is-success {
    color: var(--color-success);
    padding: 12px 16px;
    background: rgba(34, 197, 94, 0.08);
    border: 1px solid rgba(34, 197, 94, 0.2);
}

.contact-form__status.is-error {
    color: var(--color-error);
    padding: 12px 16px;
    background: rgba(239, 68, 68, 0.08);
    border: 1px solid rgba(239, 68, 68, 0.2);
}

/* ===========================
   11. Footer
   =========================== */
.site-footer {
    background: var(--color-bg-primary);
    border-top: 1px solid var(--color-border);
    padding: 48px 0 24px;
}

.footer__inner {
    display: flex;
    flex-direction: column;
    gap: 32px;
    padding-bottom: 32px;
    border-bottom: 1px solid var(--color-border);
    margin-bottom: 24px;
}

.footer__logo {
    font-family: var(--font-heading);
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--color-text-primary);
    text-decoration: none;
}

.footer__logo:hover {
    color: var(--color-text-primary);
}

.footer__tagline {
    color: var(--color-text-tertiary);
    font-size: 0.875rem;
    margin-top: 8px;
}

.footer__links {
    display: flex;
    gap: 24px;
}

.footer__link {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    text-decoration: none;
    transition: color var(--transition);
}

.footer__link:hover {
    color: var(--color-text-primary);
}

.footer__social {
    display: flex;
    gap: 16px;
}

.footer__social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-sm);
    background: var(--color-bg-secondary);
    color: var(--color-text-secondary);
    transition: all var(--transition);
}

.footer__social-link:hover {
    background: var(--color-bg-tertiary);
    color: var(--color-accent);
}

.footer__bottom {
    text-align: center;
}

.footer__bottom p {
    font-size: 0.8125rem;
    color: var(--color-text-tertiary);
}

/* ===========================
   12. Scroll Reveal Animation
   =========================== */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===========================
   13. Gradient Divider
   =========================== */
.services::before,
.contact::before {
    content: '';
    display: block;
    height: 1px;
    background: var(--gradient-accent);
    opacity: 0.2;
    margin-bottom: var(--section-padding);
}

/* ===========================
   14. Responsive - Tablet (768px)
   =========================== */
@media (min-width: 768px) {
    :root {
        --section-padding: 80px;
    }

    .container {
        padding: 0 32px;
    }

    .section-title {
        font-size: 2.5rem;
    }

    .section-subtitle {
        font-size: 1.125rem;
    }

    .hero__title {
        font-size: 3.25rem;
    }

    .hero__subtitle {
        font-size: 1.125rem;
    }

    .hero__actions {
        flex-direction: row;
        gap: 24px;
    }

    .services__grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .service-card {
        padding: 40px 32px;
    }

    .contact-form__row {
        flex-direction: row;
    }

    .footer__inner {
        flex-direction: row;
        align-items: center;
        justify-content: space-between;
    }
}

/* ===========================
   15. Responsive - Desktop (1024px)
   =========================== */
@media (min-width: 1024px) {
    :root {
        --section-padding: 100px;
    }

    .container {
        padding: 0 40px;
    }

    /* Desktop nav */
    .nav__toggle {
        display: none;
    }

    .nav__menu {
        position: static;
        width: auto;
        height: auto;
        background: transparent;
        flex-direction: row;
        align-items: center;
        gap: 32px;
    }

    .nav__list {
        flex-direction: row;
        gap: 32px;
    }

    .nav__link {
        font-size: 0.9375rem;
    }

    .nav__cta {
        padding: 10px 24px;
        font-size: 0.875rem;
    }

    /* Hero */
    .hero__title {
        font-size: 3.75rem;
    }

    /* Services grid */
    .services__grid {
        grid-template-columns: repeat(3, 1fr);
    }

    /* Why us two-column */
    .why-us__inner {
        flex-direction: row;
        align-items: center;
        gap: 80px;
    }

    .why-us__content {
        flex: 1;
    }

    .why-us__visual {
        flex-shrink: 0;
    }

    .why-us__orb {
        width: 300px;
        height: 300px;
    }

    .why-us__orb-inner {
        width: 150px;
        height: 150px;
    }
}

/* ===========================
   16. Reduced Motion
   =========================== */
@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    .reveal {
        opacity: 1;
        transform: none;
        transition: none;
    }

    .hero__scroll-hint {
        animation: none;
    }

    .why-us__orb {
        animation: none;
    }

    .service-card {
        transition: none;
    }

    .btn--primary {
        transition: none;
    }

    .btn--primary:hover {
        transform: none;
    }
}